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Sample records for culex diptera culicidae

  1. Development of the immature stages of Culex (Culex saltanensis Dyar (Diptera, Culicidae under laboratory conditions

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    João Antonio C. Zequi

    2012-03-01

    Full Text Available Development of the immature stages of Culex (Culex saltanensis Dyar (Diptera, Culicidae under laboratory conditions. Culex (Culex saltanensis Dyar, 1928 is becoming frequent and abundant in natural and artificial breeding sites in urban and rural areas of Brazil. This study contributes to the knowledge of the biology of a Brazilian strain of C. saltanensis. The development of specimens reared individually or grouped was observed. The study was conducted at a constant temperature of 27 ± 2°C, 14L:10D photoperiod and 80 ± 5% relative humidity. The immature stages were observed every 6 hours until adult emergence, which occurred in 12.29 days among individually reared specimens and in 13.12 days among group-reared specimens. Egg rafts for the experiment were obtained from the laboratory and field. Eggs hatched at a rate of 97.48 ± 2.32%. More eggs per egg raft were obtained from the field than from the laboratory. Males from individually reared specimens emerged in 12.29 ± 1.11 days and females in 13.12 ± 1.58 days. The male-female ratio was 1:1. Larval survival rate was higher than 85% for larvae reared isolated and higher than 95% for group-reared larvae. The Culex saltanensis life cycle was completed within 12 to 14 days, where larval instars I and IV took the most time to develop and the pupae, the shortest.

  2. Insecticide Susceptibility Screening Against Culex and Aedes (Diptera: Culicidae) Mosquitoes From the United States.

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    Richards, Stephanie L; Balanay, Jo Anne G; White, Avian V; Hope, Joe; Vandock, Kurt; Byrd, Brian D; Reiskind, Michael H

    2017-11-23

    Mosquitoes exposed to sublethal doses of insecticides may be selected for resistance to insecticide active ingredients (AIs). Mosquitoes are exposed to AIs through agricultural, public/private mosquito control programs, homeowners, and other sources. Hence, mosquito control programs should routinely measure the resistance/susceptibility status of mosquito populations of public health concern. The objectives here were to determine resistance status for six AIs used in adult mosquito control in the United States to assess how resistance/susceptibility differs between AI, mosquito species (states where > 1 species collected), and between years (some populations sampled for 2 yr). Field-collected eggs from 21 mosquito populations of six different species or hybrid species (Aedes albopictus Skuse [Diptera: Culicidae], Aedes aegypti L. [Diptera: Culicidae], Culex nigripalpus Theobald, Culex pipiens L. [Diptera: Culicidae], Culex quinquefasciatus Say [Diptera: Culicidae], Cx. pipiens/quinquefasciatus) were obtained. Centers for Disease Control and Prevention bottle bioassays were used to assess the resistance/susceptibility status for six AIs (bifenthrin, deltamethrin, etofenprox, malathion, permethrin, and phenothrin). World Health Organization guidelines were used to classify mosquitoes as susceptible (98-100% mortality at diagnostic time [DT]), possibly resistant (80-97% mortality at DT), or resistant (susceptibility/resistance between species and AIs. In states where both Aedes and Culex were collected, the odds of exhibiting resistance in Culex were 68-69 times higher than Aedes (Texas odds ratio: 69.30; 95% confidence interval: 5.86, 819.44; P = 0.001; North Carolina odds ratio: 67.99; 95% confidence interval: 15.21, 303.94; P < 0.0001). Some level of resistance was detected against all tested AIs in several mosquito populations and some varied between 2015 and 2016. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of

  3. Lack of cross-resistance to Mtx1 from Bacillus sphaericus in B. sphaericus-resistant Culex quinquefasciatus (Diptera: Culicidae).

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    Wei, Suzhen; Cai, Quanxin; Cai, Yajun; Yuan, Zhiming

    2007-02-01

    The toxicities of Mtx1 toxin against dipteran and lepidopteran species have been evaluated in this study. It was shown that Mtx1 has little or no toxicity to the tested lepidopteran species, but has moderate-level toxicity to Aedes albopictus Skuse (Diptera: Culicidae) and high-level toxicity to both susceptible and binary toxin-resistant Culex quinquefasciatus Say (Diptera: Culicidae). The LC(50) values of Mtx1 against a susceptible C. quinquefasciatus colony SLCq and two resistant colonies RLCq1/C3-41 and RLCq2/IAB59 selected in the laboratory with Bacillus sphaericus (Mayer & Neide) strains C3-41 and IAB59 respectively were 0.508, 0.854 and 0.675 mg L(-1) respectively. The data indicate that Mtx1 has a different mode of action from the binary toxin, and that it could be an alternative toxin to delay or overcome resistance development to binary toxin in C. quinquefasciatus.

  4. Citrus essential oils and four enantiomeric pinenes against Culex pipiens (Diptera: Culicidae).

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    Michaelakis, Antonios; Papachristos, Dimitrios; Kimbaris, Athanasios; Koliopoulos, George; Giatropoulos, Athanasios; Polissiou, Moschos G

    2009-09-01

    The aim of this study was to evaluate the toxicity of pinenes (enantiomers of alpha- and beta-) and essential oils from Greek plants of the Rutaceae family against the mosquito larvae of Culex pipiens (Diptera: Culicidae). Essential oils were isolated by hydrodistillation from fruit peel of orange (Citrus sinensis L.), lemon (Citrus limon L.), and bitter orange (Citrus aurantium L.). The chemical composition was determined by gas chromatography/mass spectrometry (GC/MS) analysis. Citrus essential oils contained in high proportion limonene and in lower quantities p-menthane molecules and pinenes. The insecticidal action of these essential oils and enantiomers of their pinenes on mosquito larvae was evaluated. Plant essential oils exhibited strong toxicity against larvae with the LC(50) values ranging from 30.1 (lemon) to 51.5 mg/L (orange) depending on Citrus species and their composition. Finally, the LC(50) value of pinenes ranging from 36.53 to 66.52 mg/L indicated an enantioselective toxicity only for the beta-pinene enantiomer.

  5. Larvicidal efficacy of medicinal plant extracts against Anopheles stephensi and Culex quinquefasciatus (Diptera: Culicidae).

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    Kamaraj, C; Abdul Rahman, A; Bagavan, A; Abduz Zahir, A; Elango, G; Kandan, P; Rajakumar, G; Marimuthu, S; Santhoshkumar, T

    2010-08-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. Natural products of plant origin with insecticidal properties have been used in recent years for control of a variety of pest insects and vectors. The present study was based on assessments of the larvicidal activity to determine the efficacies of hexane, chloroform, ethyl acetate, acetone and methanol extracts of ten medicinal plants tested against fourth instar larvae of malaria vector, Anopheles stephensi Liston and lymphatic filariasis vector, Culex quinquefasciatus Say (Diptera: Culicidae). The larvicidal activity was assessed by the procedure of WHO with some modification. The highest larval mortality was found in leaf acetone of Adhatoda vasica, bark ethyl acetate of Annona squamosa, methanol leaf and flower of Cassia auriculata, leaf ethyl acetate of Hydrocotyle javanica, methanol leaf and seed of Solanum torvum and leaf hexane extracts of Vitex negundo against the fourth instar larvae of An. stephensi and Cx. quinquefasciatus. The calculated LC90 for acetone, ethyl acetate, methanol and hexane extracts of dried leaf and bark of A. vasica, A. squamosa, S. torvum, and V. negundo were in the range of 70.38-210.68 ppm. Our results suggest that the leaf methanol extract of S.torvum and bark ethyl acetate extract of A. squamosa from Southern India have the potential for use to control mosquitoes. Therefore, this study provides the larvicidal activity against An. stephensi and Cx. quinquefasciatus of plant extracts.

  6. Laboratory and field evaluation of an oviposition trap for Culex quinquefasciatus(Diptera: Culicidae

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    Rosângela MR Barbosa

    2007-06-01

    Full Text Available An ovitrap (BR-OVT based on physical and chemical stimuli for attracting gravid Culex quinquefasciatus (Diptera: Culicidae females was developed and evaluated under laboratory and field conditions. Attractants were assayed using alternative chamber bioassays prior to being used in the BR-OVT oviposition trap. A significant preference of gravid females for sites containing conspecific egg rafts was observed, as a response to the natural oviposition pheromone, as well as for sites treated with the synthetic pheromone erythro-6-acetoxy-5-hexadecanolide. Five- to 20-day old grass infusion was strongly attractive to gravid females for laying eggs. On the other hand, entomopathogenic Bacillus sphaericus (Bs did not influence the choice of an oviposition site when used in combination with grass infusion and can therefore be used as a larvicide in ovitraps. Results from field trials showed that the BR-OVT with grass infusion and with or without Bs works as a preferred oviposition site for Cx. quinquefasciatus. The BR-OVT was more effective for egg collection when placed indoors and comparison with the number of egg rafts laid in cesspits over 40 days indicates that this very simple ovitrap may be a useful tool for monitoring populations of the most important of the vectors of bancroftian filariasis.

  7. Dispersal of Culex quinquefasciatus (Diptera: Culicidae) in a Hawaiian rain forest

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    Lapointe, D.A.

    2008-01-01

    Introduced mosquito-borne pathogens avian malaria (Plasmodium relictum Grassi and Feletti) and avian pox virus (Avipoxvirus) have been implicated in the past extinctions and declines of Hawaiian avifauna and remain significant obstacles to the recovery and restoration of endemic Hawaiian birds. Effective management of avian disease will require extensive mosquito control efforts that are guided by the local ecology of the vector Culex quinquefasciatus Say (Diptera: Culicidae). During October and November 1997 and September through November 1998 five mark-release-recapture experiments with laboratory-reared Cx. quinquefasciatus were conducted in a native rain forest on Hawaii Island. Of the overall 66,047 fluorescent dye-marked and released females, 1,192 (1.8%) were recaptured in 43-52 CO2-baited traps operated for 10-12-d trapping periods. Recaptured mosquitoes were trapped in all directions and at distances up to 3 km from the release site. The cumulative mean distance traveled (MDTs) over the trapping period ranged from a high of 1.89 km after 11 d (September 1998) to a low of 0.81 km after 11 d (November 1998). Released mosquitoes moved predominately in a downwind direction and they seemed to use forestry roads as dispersal corridors. Applying an estimated MDT of 1.6 km to a geographical information system-generated map of the Hakalau Forest National Wildlife Refuge clearly demonstrated that the effective refuge area could be reduced 60% by mosquitoes infiltrating into managed refuge lands. These findings should have significant implications for the design of future refuges and development of effective mosquito-borne avian disease control strategies.

  8. Susceptibility of Culex quinquefasciatus (Diptera: Culicidae) in Southern Louisiana to Larval Insecticides.

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    DeLisi, N; Ottea, J; Healy, K

    2017-10-06

    Mosquito control districts conduct rigorous insecticide treatments against both larval and adult Culex quinquefasciatus Say (Diptera: Culicidae), the primary vector of West Nile virus in the southern United States. However, the development of resistant populations of Cx. quinquefasciatus in response to extensive larvicide or adulticide applications has been demonstrated repeatedly across the world. Examining changes in insecticide susceptibility in treated field areas can help inform mosquito control districts as to whether or not their treatments remain effective. We hypothesized that frequent insecticide applications for the control of mosquitoes in East Baton Rouge Parish, Louisiana, lowered susceptibility of wild Cx. quinquefasciatus to larvicides. Larvicide susceptibility was measured using Lysinibacillus sphaericus, spinosad, and temephos in populations of Cx. quinquefasciatus sampled from sites in three Parishes where frequencies of insecticide applications varied, and frequencies of resistance were measured relative to a susceptible reference colony. Susceptibility to these larvicides was widespread, although fourfold resistance to the organophosphate temephos was detected at one site in East Baton Rouge Parish in the spring of 2016, which increased to eightfold resistance by the end of the mosquito season. Activities of esterases were found to be elevated in wild, temephos-resistant mosquitoes, indicating the potential role of these enzymes as a mechanism of resistance. The results of this study provide a baseline of comparison for future measurements of susceptibility in Cx. quinquefasciatus in Louisiana, and may help inform local mosquito control districts as to the effectiveness and sustainability of their insecticide programs. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  9. Larvicidal potential of medicinal plant extracts against Anopheles subpictus Grassi and Culex tritaeniorhynchus Giles (Diptera: Culicidae).

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    Kamaraj, C; Bagavan, A; Rahuman, A Abdul; Zahir, A Abduz; Elango, G; Pandiyan, G

    2009-04-01

    Mosquito control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The acetone, chloroform, ethyl acetate, hexane, methanol and petroleum ether extracts of leaf, flower and seed of Cassia auriculata L., Leucas aspera (Willd.), Rhinacanthus nasutus KURZ., Solanum torvum Swartz and Vitex negundo Linn. were tested against fourth instar larvae of malaria vector, Anopheles subpictus Grassi and Japanese encephalitis vector, Culex tritaeniorhynchus Giles (Diptera: Culicidae). The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest mortality was found in leaf petroleum ether, flower methanol extracts of C. auriculata, flower methanol extracts of L. aspera and R. nasutus, leaf and seed methanol extracts of S. torvum and leaf hexane extract of V. negundo against the larvae of A. subpictus (LC(50) = 44.21, 44.69, 53.16, 41.07, 35.32, 28.90 and 44.40 ppm; LC(90) = 187.31, 188.29, 233.18, 142.66, 151.60, 121.05 and 192.11 ppm, respectively) and against the larvae of C. tritaeniorhynchus (LC(50) = 69.83, 51.29, 81.24, 71.79, 44.42, 84.47 and 65.35 ppm; LC(90) = 335.26, 245.63, 300.45, 361.83, 185.09, 351.41 and 302.42 ppm, respectively). These results suggest that the leaf petroleum ether, flower methanol extracts of C. auriculata, leaf and seed methanol extracts of S. torvum and leaf hexane extract of V. negundo have the potential to be used as an ideal eco-friendly approach for the control of the A. subpictus and C. tritaeniorhynchus. This is the first report on the mosquito larvicidal activity of the medicinal plant extracts.

  10. Ovicidal activity of neem products (azadirachtin) against Culex tarsalis and Culex quinquefasciatus (Diptera: Culicidae).

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    Su, T; Mulla, M S

    1998-06-01

    Bioactive compounds contained in the seed kernel and other parts of the neem tree (Azadirachta indica A. Juss) have been found to show insecticidal activities and other effects in many species of insects. These activities include antifeedancy, growth regulation, fecundity suppression, male sterility, oviposition repellency, changes in biological fitness such as loss of flying ability, immunodepression, enzyme inhibition, splitting of biological rhythms, and so forth. We investigated the ovicidal effects of various formulations of azadrirachtin (AZ) against the mosquitoes Culex tarsalis Coquillett and Culex quinquefasciatus Say. The formulations tested were wettable powder Azad WP10, emulsifiable concentrate Azad EC4.5, and technically pure AZ. The ovicidal activity of the test neem products was influenced by concentration of AZ, age of the egg rafts, and age of the neem preparations. Other factors such as formulation and mosquito species were also involved in the degree of ovicidal activity. When the egg rafts were deposited directly in fresh neem suspension and left there for 4 h before transfer to untreated water, 1 ppm of AZ produced almost 100% mortality in eggs. When egg rafts aged for 0, 4, 8, 12, and 24 h were exposed to 10 ppm neem suspensions for 36 h, the ovicidal activity was only attained in the egg rafts deposited directly (0 h old) in the neem suspension, not in those with ages of 4-24 h. On aging, depending on the formulations and mosquito species, the neem suspensions at 1 ppm completely lost ovicidal activity within 7-20 days. The egg rafts of Cx. quinquefasciatus were more susceptible to the test neem products than those of Cx. tarsalis. The formulated neem products were more persistent and effective than the technical AZ. The wettable powder (WP) formulation was slightly more persistent and effective than the emulsifiable concentrate (EC). The ovicidal activity of the neem products against mosquitoes from the current research clearly demonstrated

  11. Mom Matters: Diapause Characteristics of Culex pipiens-Culex quinquefasciatus (Diptera: Culicidae) Hybrid Mosquitoes.

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    Meuti, Megan E; Short, Clancy A; Denlinger, David L

    2015-03-01

    Females of the northern house mosquito, Culex pipiens L., are capable of entering an adult overwintering diapause characterized by arrested ovarian development, enhanced stress tolerance, and elevated lipid stores. In contrast, the southern house mosquito, Culex quinquefasciatus Say, lacks this capacity and is therefore unable to survive the harsh winters found in northern regions of North America. These two species are capable of forming fertile hybrids in the United States, yet the diapause characteristics of these hybrids have not been extensively investigated. We crossed Cx. pipiens from Columbus, OH, with Cx. quinquefasciatus from Vero Beach, FL, and reared F1 hybrids from all mothers separately under diapause-inducing, short-day conditions (a photoperiod of 8:16 [L:D] h) at 18°C. Egg follicle length and lipid content were used to assess the diapause status of hybrids. Diapause incidence of hybrids varied widely for progeny from different mothers of the same species, but hybrids with Cx. pipiens mothers were consistently more prone to enter diapause than hybrids that had Cx. quinquefasciatus mothers. Our results suggest a strong maternal influence on the diapause phenotype and that a high percentage (45-75%) of Cx. pipiens-Cx. quinquefasciatus hybrids are capable of entering diapause. This implies that many hybrids can successfully overwinter, leading to a possible widening of the hybrid zone of these two species in North America. © The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Evaluation of Some Plant Fruit Extracts for the Control of West Nile Virus Vector Culex pipiens (Diptera: Culicidae)

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    Koc, Samed; Evren, Ozay Hasan; Cetin, Huseyin

    2016-01-01

    Background: The extracts of different parts of plants were found very effective against various pests. The aim of this research was to determine the insecticidal activity of fruit methanol extracts obtained from Melia azedarach (Meliaceae), Phoenix theophrasti (Arecaceae), Styphnolobium japonicum (Fabaceae) and Pyracantha coccinea (Rosaceae) against the larvae of Culex pipiens (Diptera: Culicidae). Methods: The fruits of test plants were collected from the Campus of Akdeniz University, Antalya, Turkey in 2013. A series of concentrations of the extracts ranging from 62.5–1000 ppm were tested against second instar larvae. Results: Only the extracts of Me. azedarach and Ph. theoprasti showed significant larvicidal activity against Cx. pipiens and the LC50 values of these extracts were found to be 169.48 and 220.60 ppm, respectively. This is the first research investigating the insecticidal or larvicidal activity of Ph. theophrasti, St. japonicum and Py. coccinea extracts on mosquitoes. Conclusion: The methanol extract of fruits of Me. azedarach and Ph. theophrasti showed significantly higher larvicidal activity against Cx. pipiens. PMID:28032112

  13. Larvicidal, ovicidal activities and histopathological alterations induced by Carum copticum (Apiaceae extract against Culex pipiens (Diptera: Culicidae

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    Fahd A. Al-Mekhlafi

    2018-01-01

    Full Text Available An experiment was carried out, firstly, to determine the possible toxicity of Carum copticum (Apiaceae extract against Culex pipiens (Diptera: Culicidae, and, secondly, to study the histopathological alterations in the midgut of Cx. pipiens as a result of treatment with C. copticum extract. Larvicidal and ovicidal activities of C. copticum extract against the larvae of Cx. pipiens was determined according to World health organization (WHO. The inhibition effect of C. copticum was assessed by determining the mortality of the treated larvae and eggs. The histopathological effect of the C. copticum extracts on midgut epithelium of the larvae was examined under both light and transmission electron microscopy. The crude extract of C. copticum exerted 100% mortality for Cx. pipiens after 24 h at 200 μm/ml, and zero hatchability (100% mortality at 150 μm/ml for Cx. pipiens. The histopathological study showed that larvae treated with C. copticum extract had cytopathological alterations of the midgut epithelium. The study provided information on various effects of C. copticum extract against Cx. pipiens.

  14. The distribution of potential West Nile virus vectors, Culex pipiens pipiens and Culex pipiens quinquefasciatus (Diptera: Culicidae, in Mexico City

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    Diaz-Perez Alfonso

    2011-05-01

    Full Text Available Abstract Background Culex spp. mosquitoes are considered to be the most important vectors of West Nile virus (WNV detected in at least 34 species of mosquitoes in the United States. In North America, Culex pipiens pipiens, Culex pipiens quinquefasciatus, and Culex tarsalis are all competent vectors of WNV, which is considered to be enzootic in the United States and has also been detected in equines and birds in many states of Mexico and in humans in Nuevo Leon. There is potential for WNV to be introduced into Mexico City by various means including infected mosquitoes on airplanes, migrating birds, ground transportation and infected humans. Little is known of the geographic distribution of Culex pipiens complex mosquitoes and hybrids in Mexico City. Culex pipiens pipiens preferentially feed on avian hosts; Culex pipiens quinquefasciatus have historically been considered to prefer mammalian hosts; and hybrids of these two species could theoretically serve as bridge vectors to transmit WNV from avian hosts to humans and other mammalian hosts. In order to address the potential of WNV being introduced into Mexico City, we have determined the identity and spatial distribution of Culex pipiens complex mosquitoes and their hybrids. Results Mosquito larvae collected from 103 sites throughout Mexico City during 2004-2005 were identified as Culex, Culiseta or Ochlerotatus by morphological analysis. Within the genus Culex, specimens were further identified as Culex tarsalis or as belonging to the Culex pipiens complex. Members of the Culex pipiens complex were separated by measuring the ratio of the dorsal and ventral arms (DV/D ratio of the male genitalia and also by using diagnostic primers designed for the Ace.2 gene. Culex pipiens quinquefasciatus was the most abundant form collected. Conclusions Important WNV vectors species, Cx. p. pipiens, Cx. p. quinquefasciatus and Cx. tarsalis, are all present in Mexico City. Hybrids of Cx. p. pipiens and Cx. p

  15. Impact of inorganic pollutants perchlorate and hexavalent chromium on efficacy of Bacillus sphaericus and Bacillus thuringiensis subsp. israelensis against Culex quinquefasciatus (Diptera: Culicidae).

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    Sorensen, Mary A; Walton, William E; Trumble, John T

    2007-09-01

    The effects of two widespread environmental pollutants, perchlorate and hexavalent chromium, were assessed on the efficacy of Bacillus thuringiensis subsp. israelensis (Bti) and Bacillus sphaericus (Bsph) against fourth instars of Culex quinquefasciatus Say (Diptera: Culicidae) in 24-h laboratory bioassays. Although 250 mg/liter perchlorate, a level somewhat higher than would be considered ecologically relevant, did not affect the control provided by either larvicide, presence of 1.04 mg/liter hexavalent chromium, an ecologically relevant concentration, increased the efficacy of both Bti and Bsph by 21 and 80%, respectively. In the presence of hexavalent chromium, improved suppression could be expected from Bacillus applications at the current label rates. However, because hexavalent chromium has been shown to affect many taxa, we propose that the potential exists for increased susceptibility of nontarget organisms to Bacillus products in polluted habitats.

  16. Evaluation of different formulations of IGRs against Aedes albopictus and Culex quinquefasciatus(Diptera:Culicidae)

    National Research Council Canada - National Science Library

    Gul Zamin Khan Inamullah Khan Imtiaz Ali Khan Alamzeb Muhammad Salman Kalim Ullah

    2016-01-01

    ...) of methoprene, pyriproxyfen 0.5 water dispersible granules(WDG) and pyriproxyfen 1.0 WDG were used to assess mortality and inhibition of 3rd instar larvae of Aedes albopictus and Culex quinquefasciatus...

  17. Ciclo de vida de Culex quinquefasciatus Say, 1826 (Diptera: Culicidae bajo condiciones no controladas en Bogotá.

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    Myriam Janeth Salazar

    2004-12-01

    Full Text Available El objetivo de este trabajo fue estudiar varios aspectos del crecimiento y el desarrollo de los estadios inmaduros de Culex quinquefasciatus Say, 1826 (Diptera: Culicidae, especie antropofílica frecuentemente encontrada en Bogotá. Con este fin, se realizaron dos experimentos en diferentes épocas del año 2001 (enero-febrero y septiembre-octubre, bajo condiciones no controladas (luz, temperatura y humedad relativa. Se colocaron recipientes plásticos transparentes con agua de charca a la que se le adicionó concentrado para perro; se tomaron cuatro balsas al azar para estudiar el ciclo de vida utilizando los parámetros de la tabla de vida: mortalidad y supervivencia. Las hembras ovipositaron entre cinco y ocho días después de la ingestión de sangre. El número de huevos por balsa varió entre 152 y 203. La eclosión de larvas L1 fue de 50% en el primer experimento y de 75% en el segundo. Se destacó la naturaleza no sincrónica de la eclosión de las L1, la menor duración proporcional del estadio de pupa (11% del tiempo del desarrollo total y la eficiencia del cambio pupa-adulto (98,61%. Se reporta una menor duración del ciclo de lo informado previamente. Además, los altos porcentajes de eclosión (83,58%, pupación (86,63% y emergencia (98,61% con las condiciones presentes para estos experimentos (temperatura media 14,8°C y 15,1°C y humedad relativa del 72,5% y 74,1%, respectivamente indican el alto grado de adaptación de C. quinquefasciatus al ambiente bogotano. Estas características, más la capacidad vectorial y la resistencia a los insecticidas, hacen de esta especie un problema de salud pública.

  18. COI barcode versus morphological identification of Culex (Culex) (Diptera: Culicidae) species: a case study using samples from Argentina and Brazil.

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    Laurito, Magdalena; Oliveira, Tatiane M P de; Almirón, Walter Ricardo; Sallum, Maria Anice Mureb

    2013-01-01

    Sequences of the cytochrome c oxidase subunit I (COI) mitochondrial gene from adults of 22 Culex (Culex) species from Argentina and Brazil were employed to assess species identification and to test the usefulness of COI for barcoding using the best close match (BCM) algorithm. A pairwise Kimura two-parameter distance matrix including the mean intra and interspecific distances for 71 COI barcode sequences was constructed. Of the 12 COI lineages recovered in the Neighbour-joining topology, five confirmed recognised morphological species (Cx. acharistus, Cx. chidesteri, Cx. dolosus, Cx. lygrus and Cx. saltanensis) with intraspecific divergences lower than 1.75%. Cx. bilineatus is formally resurrected from the synonymy of Cx. dolosus. Cx. maxi , Cx. surinamensis and the Coronator group species included were clustered into an unresolved lineage. The intraspecific distance of Cx. pipiens (3%) was almost twice the interspecific between it and Cx. quinquefasciatus (1.6%). Regarding the BCM criteria, the COI barcode successfully identified 69% of all species. The rest of the sequences, approximately 10%, 18% and 3%, remained as ambiguously, mis and unidentified, respectively. The COI barcode does not contain enough information to distinguish Culex (Cux.) species.

  19. Larvicidal Activity of Nerium oleander against Larvae West Nile Vector Mosquito Culex pipiens (Diptera: Culicidae)

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    El-Akhal, Fouad; Guemmouh, Raja; Ez Zoubi, Yassine; El Ouali Lalami, Abdelhakim

    2015-01-01

    Background. Outbreaks of the West Nile virus infection were reported in Morocco in 1996, 2003, and 2010. Culex pipiens was strongly suspected as the vector responsible for transmission. In the North center of Morocco, this species has developed resistance to synthetic insecticides. There is an urgent need to find alternatives to the insecticides as natural biocides. Objective. In this work, the insecticidal activity of the extract of the local plant Nerium oleander, which has never been tested before in the North center of Morocco, was studied on larval stages 3 and 4 of Culex pipiens. Methods. Biological tests were realized according to a methodology inspired from standard World Health Organization protocol. The mortality values were determined after 24 h of exposure and LC50 and LC90 values were calculated. Results. The extract had toxic effects on the larvae of culicid mosquitoes. The ethanolic extract of Nerium oleander applied against the larvae of Culex pipiens has given the lethal concentrations LC50 and LC90 in the order of 57.57 mg/mL and 166.35 mg/mL, respectively. Conclusion. This investigation indicates that N. oleander could serve as a potential larvicidal, effective natural biocide against mosquito larvae, particularly Culex pipiens. PMID:26640701

  20. Larvicidal Activity of Nerium oleander against Larvae West Nile Vector Mosquito Culex pipiens (Diptera: Culicidae

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    Fouad El-Akhal

    2015-01-01

    Full Text Available Background. Outbreaks of the West Nile virus infection were reported in Morocco in 1996, 2003, and 2010. Culex pipiens was strongly suspected as the vector responsible for transmission. In the North center of Morocco, this species has developed resistance to synthetic insecticides. There is an urgent need to find alternatives to the insecticides as natural biocides. Objective. In this work, the insecticidal activity of the extract of the local plant Nerium oleander, which has never been tested before in the North center of Morocco, was studied on larval stages 3 and 4 of Culex pipiens. Methods. Biological tests were realized according to a methodology inspired from standard World Health Organization protocol. The mortality values were determined after 24 h of exposure and LC50 and LC90 values were calculated. Results. The extract had toxic effects on the larvae of culicid mosquitoes. The ethanolic extract of Nerium oleander applied against the larvae of Culex pipiens has given the lethal concentrations LC50 and LC90 in the order of 57.57 mg/mL and 166.35 mg/mL, respectively. Conclusion. This investigation indicates that N. oleander could serve as a potential larvicidal, effective natural biocide against mosquito larvae, particularly Culex pipiens.

  1. Comparative analysis of gut microbiota of Culex restuans (Diptera: Culicidae) females from different parents

    Science.gov (United States)

    The potential for gut microbiota to impede or enhance pathogen transmission is well-documented but the factors that shape this microbiota in mosquito vectors are poorly understood. We characterized and compared the gut microbiota of adult females of Culex restuans Theobald from different parents. Cu...

  2. Laboratory and field evaluation of medicinal plant extracts against filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae)

    Science.gov (United States)

    In this study, chemical extracts of Jatropha curcas, Hyptis suaveolens, Abutilon indicum, and Leucas aspera were tested for toxicity to larvae of the filariasis vector Culex quinquefasciatus. Respective median lethal concentrations (LC50) for hexane, chloroform, ethyl acetate, and methanol extracts...

  3. Evaluation of different formulations of IGRs against Aedes albopictus and Culex quinquefasciatus (Diptera: Culicidae

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    Gul Zamin Khan

    2016-06-01

    Conclusions: It is thus concluded that IGRs can be utilized as environment friendly control measures for Culex and Aedes spp. of mosquitoes on small and large scale. This will reduce the use of conventional insecticides by the public health authorities and help in reducing selection pressure of insecticides.

  4. Contributions to the Mosquito Fauna of Southeast Asia - II. The Genus Culex in Thailand (Diptera: Culicidae)

    Science.gov (United States)

    1967-01-01

    Pui Doi Mountain, Chiang Mai, Thailand. Iyengar (1938) reported pallidothorax as a carrier of Wuchereria maluyi. Hu ( 1940 ) induced starved females to...Dyar and Knab 1914, Inset. Inscit. menst. 2: 58. Type species: Phalangomyiu debilis Dyar and Knab. Laiomyia Izquierdo 1916, Tesis. Col. Est. Puebla ...M. K. 1940 . HU, S. M. K. 1958. Culex pallidothorax Theobald as a carrier of Wuchereriu bancrofti Cobbold. Lingnan Sci. J. 19: 543-547. Progress

  5. Morphometric geometric study of wing shape in Culex quinquefasciatus Say (Diptera: Culicidae from Tamil Nadu, India

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    K. Manimegalai

    2009-05-01

    Full Text Available The morphometric geometric study was carried out in 10 males and 10 females of Culex quinquefasciatus. There are 23 landmarks corresponding to points at which wing veins either branch or intersect the margin of the wing. Relative warp analysis has been proved to be very efficient in distinguishing the variation of shape in male and female wings. The multivariate analysis of co-variance (MANCOVA showed a clear separation of the male and female wings.

  6. The Morphological Variations of Culex pipiens Larvae (Diptera: Culicidae in Yazd Province, Central Iran

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    H Dehghan

    2010-12-01

    Full Text Available "nAbstract "nBackground: Culex pipiens complex shows variations in morphological and biological characters including differ­ent biological forms and has medical and veterinary importance. Because of having morphological variations, some­times it is not easy to separate this species from Cx. quinquefasciatus and Cx. torrentium. The aim of this study was to  identify the  Culex pipiens complex species in order to use in control programs in the future. "nMethods: This study was carried out in two randomly selected rural villages in Yazd County, eastern Iran using dip­ping technique from April to October 2009. The data were analyzed using SPSS software version 16. "nResults: Average of siphon index in fourth-instrar larvae was 3.86±0.03, the minimum and maximum were calculated 2.43 and 5.14, respectively. Siphon/Saddle index was measured as average, minimum and maximum 3.2±0.2, 2.78, and 4.42 respectively. In our study, only 4 specimens had single seta 1 on segments III and VI (2.5% and the remaining beard double seta (97.5%. The maximum 3-6 branches seta 1a-S and 1b-S (95% were observed on siphon. "nConclusion: More populations of Culex pipiens from different areas of Iran need to be studied to gain complete informa­tion about the taxonomy and ecology of the species in the country. "n  "nKeywords: Culex pipiens complex, larvae, taxonomy, Iran

  7. The Previously Undetected Presence of Culex restuans (Diptera: Culicidae) in Central America, with Notes on Identification

    Science.gov (United States)

    1988-01-01

    California -Central America populations and those of the rest of the United States and Canada. The presence of hindtarsal banding in the first group and...to acknowledge Taina Litwak for preparation of the figures. REFERENCES CITED Bohart, R.M. and R.K. Washino. 1978. Mosquitoes of California . Third... Psorophora cingulata and Uranotaenia apicalis in Guatemala. Mosq. Syst. 15: 28-32. Darsie, R.F., Jr. 1984. The presence of Psorophora cilipes (Diptera

  8. Estimation of Genetic Divergence and Gene Flow between Culex pipiens and Culex quinquefasciatus (Diptera: Culicidae in Argentina

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    Humeres Silvia G

    1998-01-01

    Full Text Available Allele frequencies at seven polymorphic loci controlling the synthesis of enzymes were analyzed in six populations of Culex pipiens L. and Cx. quinquefasciatus Say. Sampling sites were situated along a north-south line of about 2,000 km in Argentina. The predominant alleles at Mdh, Idh, Gpdh and Gpi loci presented similar frequencies in all the samples. Frequencies at the Pgm locus were similar for populations pairs sharing the same geographic area. The loci Cat and Hk-1 presented significant geographic variation. The latter showed a marked latitudinal cline, with a frequency for allele b ranging from 0.99 in the northernmost point to 0.04 in the southernmost one, a pattern that may be explained by natural selection (FST = 0.46; p < 0.0001 on heat sensitive alleles. The average value of FST (0.088 and Nm (61.12 indicated a high gene flow between adjacent populations. A high correlation was found between genetic and geographic distance (r = 0.83; p < 0.001. The highest genetic identity (IN = 0.988 corresponded to the geographically closest samples from the central area. In one of these localities Cx. quinquefasciatus was predominant and hybrid individuals were detected, while in the other, almost all the specimens were identified as Cx. pipiens. To verify the fertility between Cx. pipiens and Cx. quinquefasciatus from the northern- and southernmost populations, experimental crosses were performed. Viable egg rafts were obtained from both reciprocal crosses. Hatching ranged from 76.5 to 100%. The hybrid progenies were fertile through two subsequent generations

  9. Bionomics and Vector Potential of Culex thriambus (Diptera: Culicidae) Mosquitoes in Lake County, California.

    Science.gov (United States)

    Nelms, Brittany M; Thiemann, Tara C; Bridges, Danielle N; Williams, Alan E; Koschik, Michelle L; Ryan, Bonnie M; Scott, Jamesina J

    2016-11-01

    California statewide West Nile virus (WNV) minimum infection rates in Culex thriambus Dyar mosquitoes are high; however, few specimens are submitted and tested each year, as their distribution seems limited to larval habitats along riparian systems. To evaluate the role of Cx. thriambus in the amplification, maintenance, and overwintering of WNV in Lake County, CA, the bionomics and vector potential of the species was investigated during 2014 and 2015. Culex thriambus was the most abundant mosquito species, with 1,153 adults and 7,624 immatures collected by vacuum aspiration and dip sampling, respectively, at the primary study site. Detection of WNV in four mosquito pools during September through November coincided with peak seasonality. Females entered and maintained a reproductive diapause during winter under field and seminatural conditions. Diapause was initiated in the majority of Cx. thriambus females by October and was terminated by 30 March. Some parous females (7.1%) and those in host-seeking arrest (7.1%) were collected throughout the winter period. An accrual of 679.51 degree-days (°D) was necessary for diapause termination under seminatural conditions. Culex thriambus females fed on 16 different avian species during spring and summer, and no mammalian feeds were detected. West Nile viral RNA was detected in four of 42 Cx. thriambus pools tested during June through November and infection rates ranged from 3.53-28.15/1,000 tested. In summary, WNV transmission may be increased along riparian corridors throughout California where Cx. thriambus mosquitoes remain relatively abundant. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.

  10. Baseline Susceptibility of Filarial Vector Culex quinquefasciatus (Diptera: Cu-licidae to Five Insecticides with Different Modes of Action in Southeast of Iran

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    Yaser Salim-Abadi

    2017-12-01

    Full Text Available Background: Culex quinquefasciatus (Diptera: Culicidae is an important vector for many human diseases. The aim of this study was to evaluate the susceptibility level of larval and adult stages of Cu. quinquefasciatus to different groups of WHO recommended insecticides for vector control.Methods: Larval stages of the Culex mosquitoes were collected from their natural habitats in Rafsanjan County at Kerman Province, southeast of Iran in 2016. Insecticide susceptibility status of adult female Cx. quinquefasciatus against DDT (4%, deltamethrin (0.05%, malathion 5%, and bendiocarb (0.1% were determined using WHO stand­ard insecticide susceptibility test. Additional test was carried out to determine the susceptibility status of larvae of Cx. quinquefasciatus to temephos. Bioassay data were analyzed by Probit program.Results: Cx. quinquefasciatus adults showed resistance to all four groups of the tested insecticides according to the WHO criteria for resistance evaluation. The lethal concentrations for 50% mortality (LC50 and 90% mortality (LC90 of temephos against Cx. quinquefasciatus larvae were 0.18mg/l and 0.78mg/l, respectively. This finding also con­firms resistance to temephos based on the WHO recommended instructions for resistance evaluation.Conclusion: Resistance to all groups of the tested insecticides should be considered for future vector control investi­gations in the study area.

  11. Larvicidal activity of Nerium oleander L. (Apocynaceae flower extracts against Culex quinquefasciatus Say (Diptera: Culicidae

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    R. Raveen

    2014-03-01

    Full Text Available Culex quinquefasciatus is the vector responsible for serious disease filariasis among human beings. Plant derived products have received increased attention from scientists as they serve as a rich source for novel natural substances possessing insecticidal properties which are safe to human and ecosystem. During the last decade, various studies on natural plant products against vector mosquito indicate them as possible alternatives to chemical and synthetic insecticides for mosquito control. In the present study, the crude hexane and aqueous extract of Nerium oleander flowers were reported for larvicidal activity against the filarial vector, Culex quinquefasciatus. Mortality was observed for 24 and 48 hours. Hexane flower extract exhibited highest larvicidal activity with a LC50 value of 102.54 ppm and 61.11ppm after 24 and 48 hours respectively. Further investigations are needed to elucidate this activity against a wide range of all stages of mosquito species and also the active ingredient(s of the extract responsible for larvicidal activity should be identified.

  12. Toxic Response of Mosquito Culex Quinquefasciatus (Diptera: Culicidae to some Agricultural Pesticides (Butachlor and Pertilachlor

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    Aliakbar Hedayati*

    2017-06-01

    Full Text Available Background: The expansion of herbicide used in aquatic ecosystems as well as in terrestrial if is not properly controlled may produce harmful effects on freshwater fisheries. Residue limits of these agricultural chemicals in tropical fishery waters should be established. The aim of this study was to determine the acute toxicity of butachlor and pertilachlor as potential dangerous herbicides to assess mortality effects of these chemicals to the Mosquito Culex quinquefasciatus. Methods: This study was carried out in Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran at summer 2013. Culex samples were exposed to different concentrations of butachlor and pertilachlor (0-200ppm for butachlor and pertilachlor for 96 h. Results: The low toxicity of LC50s obtained for butachlor (23.81±0.04 and pertilachlor (27.97±0.05 indicate that butachlor and pertilachlor were lowly toxic to Mosquito Cu. quinquefasciatus. Conclusion: Although pretilachlor and butachlor are low toxic but pretilachlor is less toxic in field conditions, these data are useful to potential ecosystem risk assessment.

  13. Larval Habitat Characteristics of Mosquitoes of the Genus Culex (Diptera: Culicidae in Guilan Province, Iran

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    S Azari-Hamidian

    2007-05-01

    Full Text Available An investigation was carried out during April to December 2000 to study mosquito fauna and ecology in Guilan Prov¬ince of northern Iran. The mosquito larvae were collected by dipping method and larval habitat characteristics recorded ac¬cording to hydro-ecological features. In total, 3937 larvae of the genus Culex from 92 larval breeding sites were collected. Six spe¬cies of the genus Culex; Cx. mimeticus, Cx. pipiens, Cx. theileri, Cx. tritaeniorhynchus, Cx. hortensis, and Cx. terri¬tans were identified in the province and respectively comprised 10.3%, 47.2%, 2.2%, 31%, 6.5%, and 2.8% of the samples. Most of the larvae were collected from the natural habitats (75.6% such as river edges (6.5%, riverbed pools (28.2%, rain pools (47.8%, stream edges (9.4%, grasslands (1.9%, marshes (2.8%, and hoof-prints (3.4% and others from artificial habitats (24.4% including rice fields (32.1%, irrigation channels (7.1%, wells (16.4%, discarded concrete tubes (33.1%, dis¬carded tires (11.0%, and agricultural water-storage pools (0.3%. The ecology of Cx. pipiens and Cx. tritaeniorhynchus, which are the most prevalent species and potentially involved in the transmission of many pathogens to humans and domes¬ticated animals, must be extensively studied.

  14. Laboratory and field evaluation of spinosad formulation Natular T30 against immature Culex mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Su, Tianyun; Cheng, Min-Lee; Thieme, Jennifer

    2014-07-01

    Spinosad consisting of spinosyn A and D is derived from a naturally occurring, soil-dwelling bacterium, Saccharopolyspora spinosa. Spinosyns are neurotoxins that activate postsynaptic nicotinic acetylcholine and gamma-aminobutyric acid receptors and cause rapid excitation of the insect nervous system and ultimately exhaustion and death of the targets. During the past 30 yr, numerous spinosad-based formulations have been developed and applied to control various arthropod pests of agricultural importance. Natular T-30 is a new slow-release formulation containing 8.33% spinosad for use in mosquito larval control programs. High-level larvicidal activity, as indicated by low LC50 and LC90 levels, was demonstrated against Culex quinquefasciatus Say in the laboratory. Larvicidal efficacy was evaluated in semifield microcosms, field mesocosms, and underground storm drains. Fair performance against larval populations of Culex spp. and other mosquito species was achieved, although low efficacy during the initial few days posttreatment was encountered. This slow-release formulation will play an important role in controlling mosquitoes in persistent breeding sources.

  15. A Pictorial Key for Culex pipiens Complex (Diptera: Culicidae In Iran

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    Hossein Dehghan

    2016-01-01

    Full Text Available Background: The aim of this study was to design pictorial key and taxonomic literature of Culex pipiens complex in Iran.Methods: Larvae were collected using standard dipping methods in 13 randomly selected areas of Bushehr, Hame­dan, Kerman, Khorasan-e-Razavi, Khuzistan, Mazandaran, Tehran, Sistan and Baluchistan and Yazd Provinces from April 2009 to October 2010. The data were analyzed using SPSS Ver. 11.5.Results: Culex pipiens larvae were identified based on the Seta 1 of the abdominal segments III–IV in north and central parts of Iran. This diagnostic character had some variation among the Cx. quinquefasciatus collected from south of the country. The identification value of intersection of costa, subcosta and bifurcation of R2+3 of female veins, was calculated as 90–100 % for Cx. pipiens. This diagnostic character was varied among the Cx. quinquefas­ciatus specimens. The male genitalia found as the main characters to distinguish of Cx. quinquefasciatus from Cx. pipiens.Conclusion: It is necessary more studies on the behavior and genetic variations of Cx. pipiens complex in Iran.

  16. Larval Habitat Characteristics of Mosquitoes of the Genus Culex (Diptera: Culicidae in Guilan Province, Iran

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    S Azari-Hamidian

    2007-06-01

    Full Text Available An investigation was carried out during April to December 2000 to study mosquito fauna and ecology in Guilan Prov¬ince of northern Iran. The mosquito larvae were collected by dipping method and larval habitat characteristics recorded ac¬cording to hydro-ecological features. In total, 3937 larvae of the genus Culex from 92 larval breeding sites were collected. Six spe¬cies of the genus Culex; Cx. mimeticus, Cx. pipiens, Cx. theileri, Cx. tritaeniorhynchus, Cx. hortensis, and Cx. terri¬tans were identified in the province and respectively comprised 10.3%, 47.2%, 2.2%, 31%, 6.5%, and 2.8% of the samples. Most of the larvae were collected from the natural habitats (75.6% such as river edges (6.5%, riverbed pools (28.2%, rain pools (47.8%, stream edges (9.4%, grasslands (1.9%, marshes (2.8%, and hoof-prints (3.4% and others from artificial habitats (24.4% including rice fields (32.1%, irrigation channels (7.1%, wells (16.4%, discarded concrete tubes (33.1%, dis¬carded tires (11.0%, and agricultural water-storage pools (0.3%. The ecology of Cx. pipiens and Cx. tritaeniorhynchus, which are the most prevalent species and potentially involved in the transmission of many pathogens to humans and domes¬ticated animals, must be extensively studied.

  17. Temperature effects on the immature development time of Culex eduardoi Casal and Garcia (Diptera: Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Loetti, V.; Schweigmann, N.J.; Burroni, N.E., E-mail: nburroni@ege.fcen.uba.a [Universidad de Buenos Aires (Argentina). Facultad de Ciencias Exactas y Naturales. Grupo de Estudio de Mosquitos

    2011-01-15

    The effect of constant temperatures on the development time from first instar to adult emergence was studied in Culex eduardoi Casal and Garcia reared at 7, 10, 15, 20, 25, 30 or 33 deg C. Data were adjusted to the linear degree-day model and the nonlinear Briere model. According to the linear model, the development time was inversely related to the rearing temperatures between 7 deg C and 25 deg C. Maximum mortality (100%) was recorded at temperatures > 30 deg C. According to the linear model, the development threshold temperature and thermal constant were 5.7 deg C and 188.8 degree days, respectively. The lower and upper threshold temperatures and the optimum temperature for the nonlinear model were -2.3, 30.0 and 28.1 deg C, respectively. (author)

  18. Classification within the cosmopolitan genus Culex (Diptera: Culicidae): the foundation for molecular systematics and phylogenetic research.

    Science.gov (United States)

    Harbach, Ralph E

    2011-01-01

    The internal classification of the cosmopolitan and medically important genus Culex is thoroughly reviewed and updated to reflect the multitude of taxonomic changes and concepts which have been published since the classification was last compiled by Edwards in 1932. Both formal and informal taxa are included. The classification is intended to aid researchers and students who are interested in analyzing species relationships, making group comparisons and testing phylogenetic hypotheses. The genus includes 768 formally recognized species divided among 26 subgenera. Many of the subgenera are subdivided hierarchically into nested informal groups of morphologically similar species that are believed to represent monophyletic lineages based on morphological similarity. The informal groupings proposed by researchers include Sections, Series, Groups, Lines, Subgroups and Complexes, which are unlikely to be phylogenetically equivalent categories among the various subgenera. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Insecticidal properties of essential plant oils against the mosquito Culex pipiens molestus (Diptera: Culicidae).

    Science.gov (United States)

    Traboulsi, Abdallah F; Taoubi, K; el-Haj, Samih; Bessiere, J M; Rammal, Salma

    2002-05-01

    The insecticidal activities of essential oil extracts from leaves and flowers of aromatic plants against fourth-instar larvae of the mosquito Culex pipiens molestus Forskal were determined. Extracts of Myrtus communis L were found to be the most toxic, followed by those of Origanum syriacum L, Mentha microcorphylla Koch, Pistacia lentiscus L and Lavandula stoechas L with LC50 values of 16, 36, 39, 70 and 89 mg litre-1, respectively. Over 20 major components were identified in extracts from each plant species. Eight pure components (1,8-cineole, menthone, linalool, terpineol, carvacrol, thymol, (1S)-(-)-alpha-pinene and (1R)-(+)-alpha-pinene) were tested against the larvae. Thymol, carvacrol, (1R)-(+)-alpha-pinene and (1S)-(-)-alpha-pinene were the most toxic (LC50 = 36-49 mg litre-1), while menthone, 1,8-cineole, linalool and terpineol (LC50 = 156-194 mg litre-1) were less toxic.

  20. Experimental host preference of diapause and non-diapause induced Culex pipiens pipiens (Diptera: Culicidae).

    Science.gov (United States)

    Faraji, Ary; Gaugler, Randy

    2015-07-24

    Culex pipiens pipiens plays an important role in the transmission of several vector-borne pathogens such as West Nile virus (WNV) in North America. Laboratory and field studies suggest that this species is ornithophilic but because of genetic hybridization with sibling species during the active mosquito season, it may occasionally feed on mammals. Adult female Cx. p. pipiens undergo a facultative diapause and may serve as an overwintering mechanism for WNV. To determine the effect of diapause on the innate host preference of Cx. p. pipiens emerging from winter hibernation, we conducted host-choice experiments using bird and mammal hosts. Mosquitoes were reared under non-diapause induced (NDI), diapause induced (DI), and field collected from overwintering (OW) hibernaculae. They were released into a large mesh enclosure housing two lard can traps, and given a choice between feeding on a dove or a rat. Host seeking Cx. p. pipiens were four times more likely to feed on the dove than the rat, regardless of experimental conditions. Under NDI conditions, Cx. p. pipiens were (p diapause in temperate habitats where winter survival is crucial for disease transmission cycles. Although we showed that Cx. p. pipiens prefers an avian to a mammalian host, nearly 20% of emerging mosquitoes in the spring could feed on mammals. Changes in host preferences may also contain valuable clues about transmission dynamics and subsequent timely interventions by vector control and public health practitioners.

  1. Bacillus thuringiensis isolates entomopathogenic for Culex quinquefasciatus (Diptera: Culicidae and Anticarsia gemmatalis (Lepidoptera: Noctuidae

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    V. Gobatto

    Full Text Available Samples of the Bacillus thuringiensis (Bt were collected from soil and insects. Eight isolates were selected from rural soil, 15 from urban soil and 11 from insects. These were evaluated for entomopathogenicity against larvae of Anticarsia gemmatalis and Culex quinquefasciatus. The pathogenicity tests showed that a higher percentage of isolates were active against A. gemmatalis (60% compared to C. quinquefasciatus (31%. Probit analysis (LC50 indicated that against A. gemmatalis four of the isolates presented values similar to the reference strain against A. gemmatalis, while against C. quinquefasciatus one isolate showed an LC50 similar to the reference strain (IPS-82. SDS-PAGE characterisation of two isolates showed a 27 kDa protein fraction related to the Bt subspecies israelensis cytolytic toxin (cyt gene. One 130 kDa protein, possibly related to the Bt crystal inclusions (cry1 gene, was identified in the other two isolates, which were more toxic for lepidoptera; another isolate presented a protein of 100 kDa. Some new local Bt isolates had similar LC50 probit values to the reference strains.

  2. The Role of Culex pipiens L. (Diptera: Culicidae in Virus Transmission in Europe

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    Victor A. Brugman

    2018-02-01

    Full Text Available Over the past three decades, a range of mosquito-borne viruses that threaten public and veterinary health have emerged or re-emerged in Europe. Mosquito surveillance activities have highlighted the Culex pipiens species complex as being critical for the maintenance of a number of these viruses. This species complex contains morphologically similar forms that exhibit variation in phenotypes that can influence the probability of virus transmission. Critical amongst these is the choice of host on which to feed, with different forms showing different feeding preferences. This influences the ability of the mosquito to vector viruses and facilitate transmission of viruses to humans and domestic animals. Biases towards blood-feeding on avian or mammalian hosts have been demonstrated for different Cx. pipiens ecoforms and emerging evidence of hybrid populations across Europe adds another level of complexity to virus transmission. A range of molecular methods based on DNA have been developed to enable discrimination between morphologically indistinguishable forms, although this remains an active area of research. This review provides a comprehensive overview of developments in the understanding of the ecology, behaviour and genetics of Cx. pipiens in Europe, and how this influences arbovirus transmission.

  3. Establishment and characterisation of a new cell line derived from Culex quinquefasciatus (Diptera: Culicidae

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    Nidya A Segura

    2012-02-01

    Full Text Available Insect cell cultures are an important biotechnological tool for basic and applied studies. The objective of this work was to establish and characterise a new cell line from Culex quinquefasciatus embryonic tissues. Embryonated eggs were taken as a source of tissue to make explants that were seeded in L-15, Grace's, Grace's/L-15, MM/VP12, Schneider's and DMEM culture media with a pH range from 6.7-6.9 and incubated at 28ºC. The morphological, cytogenetic, biochemical and molecular characteristics of the cell cultures were examined by observing the cell shapes, obtaining the karyotypes, using a cellulose-acetate electrophoretic system and performing random amplified polymorphic DNA-polymerase chain reaction analysis, respectively. The Grace's/L-15 medium provided the optimal nutritional conditions for cell adhesion and proliferation. Approximately 40-60 days following the explant procedure, a confluent monolayer was formed. Cellular morphology in the primary cultures and the subcultures was heterogeneous, but in the monolayer the epithelioid morphology type predominated. A karyotype with a diploid number of six chromosomes (2n = 6 was observed. Isoenzymatic and molecular patterns of the mosquito cell cultures matched those obtained from the immature and adult forms of the same species. Eighteen subcultures were generated. These cell cultures potentially constitute a useful tool for use in biomedical applications.

  4. Adulticidal efficacy of Delonix elata against filariasis vector mosquito, Culex quinquefasciatus (Diptera: Culicidae

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    Mohan Rajeswary

    2014-09-01

    Full Text Available Objective: To evaluate the adulticidal activity and toxicity of different solvent crude extracts of Delonix elata (D. elata against filariasis vector mosquito Culex quinquefasciatus (Cx. quinquefasciatus. Methods: The adulticidal activities of crude hexane, benzene, ethyl acetate, chloroform and methanol leaf and seed extracts of D. elata were assayed for their toxicity against vector mosquito Cx. quinquefasciatus. Bioassay was carried out by WHO method for determination of adulticidal activity against mosquitoes. The adult mortality was observed after 24 h of exposure. Results: All extracts showed moderate adulticidal effects; however, the highest adult mortality was found in methanol extract of D. elata leaf against the adults of Cx. quinquefasciatus with the LC50 and LC90 values at 197.28 and 347.45mg/L, respectively. Conclusions: These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes. This study provides first report on the mosquito adulticidal activity of D. elata plant extracts against filariasis vector mosquito, Cx. quinquefasciatus.

  5. High Insecticides Resistance in Culex pipiens (Diptera: Culicidae from Tehran, Capital of Iran

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    Yaser Salim-Abadi

    2016-10-01

    Full Text Available Background: During recent years transmission of Dirofilaria immitis (dog heart worm by Culex pipiens and West Nile virus have been reported from Iran. The present study was preformed for evaluating the susceptibility status of Cx. pipiens collected from capital city of Tehran, Iran.Methods: Four Insecticides including: DDT 4%, Lambdacyhalothrin 0.05%, Deltamethrin 0.05% and Cyfluthrin 0.15 % according to WHO standard  methods were used for evaluating the susceptibility status of Cx. pipiens from Tehran moreover  For comparison susceptibility status a Laboratory strain also was used.  Bioassay data were ana­lyzed using Probit program. The lethal time for 50% and 90% mortality (LT50 and LT90 values were calculated from regression line.Results: The susceptibility status of lab strain of Cx. pipiens revealed that it is susceptible to Lambdacyhalothrin, Deltamethrin, Cyfluthrin and resistant to DDT. Moreover cyfluthrin with LT50=36 seconds and DDT with LT50=3005 seconds had the least and most LT50s. Field population was resistance to all tested insecticides and DDT yielded no mortality.Conclusion: Highly resistance level against all WHO recommended imagicides were detected in field populations. We suggest more biochemical and molecular investigations to detect resistance mechanisms in the field population for further decision of vector control.

  6. Larvicidal potential of Acorus calamus L. essential oil against filarial vector mosquito Culex quinquefasciatus (Diptera: Culicidae

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    A Senthilkumar

    2012-08-01

    Full Text Available Objective: To identify the chemical composition and larvicidal activity of Acorus calamus (A. calamus rhizome essential oil against the filarial vector mosquito, Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Essential oil was isolated by hydro-distillation and the chemical composition of the oil was analysed by gas chromatography and gas chromatography mass spectroscopy analysis. The larvicidal activity of the essential oil was analysed at different concentrations, viz., 12.5, 25.0, 50.0, 100.0 and 200.0 mL/L. Early 4th instar larvae were used for the larvicidal assay. The larval mortality was calculated after 24 h of the exposure. Results: The gas chromatography and gas chromatography mass spectroscopy analysis showed that the essential oil extracted from the rhizome of A. calamus contained 20 chemical compounds representing about 99.99% of the total oil. Beta-asarone (33.36%, cis-beta-terpineol (23.44%, limonene (13.08%, carvone (5.64% and amyl isovalerate (4.92% were identified as the major chemical compounds. The essential oil had promising larvicidal effect against the early 4th instar larvae of Cx. quinquefasciatus with LC 50 value of 63.43 mL/L and LC90 value of 145.95 mL/L. Conclusions: The essential oil of A. calamus rhizome can be used as a natural larvicidal agent against the larvae of filarial vector mosquito, Cx. quinquefasciatus.

  7. Asymmetrical Competition between Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae Coexisting in Breeding Sites

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    Juan C. Santana-Martínez

    2017-10-01

    Full Text Available Aedes aegypti and Culex quinquefasciatus are mosquito vectors for several tropical diseases that represent a current public health problem. The ecological requirements for each species are different, however, both species show high biological adaptability, which promotes their coexistence in the same breeding sites. The purpose of this study was to assess the effect of larval association between Ae. aegypti and Cx. quinquefasciatus under different laboratory conditions of food supply and temperature, and under field simulated conditions like peridomestic containers. Our findings showed that under field simulated conditions there was no asymmetrical competition in mixed cultures with the different Cx. quinquefasciatus/Ae. aegypti ratios tested. However, under laboratory conditions in which different doses of food supply were evaluated, it was observed that competition between the two species takes place. Larval coexistence under food scarcity conditions (0.95 mg/larva showed that Ae. aegypti had a greater adult emergence than Cx. quinquefasciatus and was capable of depriving Cx. quinquefasciatus of the food needed to complete metamorphosis. In an intermediate dose of food (1.9 mg/larva, the dry weight of Cx. quinquefasciatus adults decreased, and their larval development time increased when Cx. quinquefasciatus/Ae. aegypti ratio was low. Also, a temperature effect was assessed demonstrating that Cx. quinquefasciatus was more vulnerable to changes in temperature. We suggest that Ae. aegypti is more successful in exploiting microhabitats when food is scarce, due to its scrape active feeding habitats and fast larval development times. Therefore, in conditions of food paucity both species will compete, and Ae. aegypti larvae will prevail.

  8. Laboratory and field evaluation of medicinal plant extracts against filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Kovendan, Kalimuthu; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Mahesh Kumar, Palanisamy; Amerasan, Duraisamy; Subramaniam, Jayapal; Vincent, Savariar; Barnard, Donald R

    2012-06-01

    The present study explored the effects of Jatropha curcas, Hyptis suaveolens, Abutilon indicum, and Leucas aspera tested against third instar larvae of filarial vector, Culex quinquefasciatus. The dried plant materials were powdered by an electrical blender. From each sample, 500 g powder was macerated with 1.5 L of hexane, chloroform, ethyl acetate, and methanol 8h, using Soxhlet apparatus, and filtered. The extracts were concentrated at reduced temperature on a rotary evaporator and stored at a temperature of 4°C. The yield of crude extract was 11.4, 12.2, 10.6, and 13.5 g in hexane, chloroform, ethyl acetate, and methanol, respectively. The hexane, chloroform, ethyl acetate, and methanol extract of J. curcas with LC(50) values of 230.32, 212.85, 192.07, and 113.23 ppm; H. suaveolens with LC(50) values of 213.09, 217.64, 167.59, and 86.93 ppm; A. indicum with LC(50) values of 204.18, 155.53, 166.32, and 111.58 ppm; and L. aspera with LC(50) values of 152.18, 118.29, 111.43, and 107.73 ppm, respectively, against third instar larvae of C. quinquefasciatus. The larval mortality was observed after 24 h of exposure. Maximum larvicidal activity was observed in the methanolic extract followed by ethyl acetate, chloroform, and hexane extract. No mortality was observed in the control. The observed mortality were statistically significant at P management. The present results suggest that the medicinal plants extract was an excellent potential for controlling filarial vector, C. quinquefasciatus.

  9. Pterodon emarginatus oleoresin-based nanoemulsion as a promising tool for Culex quinquefasciatus (Diptera: Culicidae) control.

    Science.gov (United States)

    Oliveira, Anna E M F M; Duarte, Jonatas L; Cruz, Rodrigo A S; Souto, Raimundo N P; Ferreira, Ricardo M A; Peniche, Taires; da Conceição, Edemilson C; de Oliveira, Leandra A R; Faustino, Silvia M M; Florentino, Alexandro C; Carvalho, José C T; Fernandes, Caio P

    2017-01-03

    Preparation of nanoformulations using natural products as bioactive substances is considered very promising for innovative larvicidal agents. On this context, oil in water nanoemulsions develop a main role, since they satisfactorily disperse poor-water soluble substances, such as herbal oils, in aqueous media. Pterodon emarginatus, popularly known as sucupira, has a promising bioactive oleoresin. However, to our knowledge, no previous studies were carried out to evaluate its potential against Culex quinquefasciatus, the main vector of the tropical neglected disease called lymphatic filariasis or elephantiasis. Thus, we aimed to investigate influence of different pairs of surfactants in nanoemulsion formation and investigate if a sucupira oleoresin-based nanoemulsion has promising larvicidal activity against this C. quinquefasciatus. We also evaluated morphological alteration, possible mechanism of insecticidal action and ecotoxicity of the nanoemulsion against a non-target organism. Among the different pairs of surfactants that were tested, nanoemulsions obtained with polysorbate 80/sorbitan monooleate and polysorbate 80/sorbitan trioleate presented smallest mean droplet size just afterwards preparation, respectively 151.0 ± 2.252 and 160.7 ± 1.493 nm. They presented high negative zeta potential values, low polydispersity index (nanoemulsion prepared with polysorbate 80/sorbitan monooleate was considered more stable and was chosen for biological assays. It presented low LC50 value against larvae (34.75; 7.31-51.86 mg/L) after 48 h of treatment and some morphological alteration was observed. The nanoemulsion did not inhibit acetylcholinesterase of C. quinquefasciatus larvae. It was not toxic to green algae Chlorella vulgaris at low concentration (25 mg/L). Our results suggest that optimal nanoemulsions may be prepared with different surfactants using a low cost and low energy simple method. Moreover, this prototype proved to be effective against C

  10. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 10- survey of adult behaviour of Culex nigripalpus and other species of Culex (Culex in South-Eastern Brazil

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    Oswaldo Paulo Forattini

    1995-08-01

    Full Text Available A survey of adult behaviour of Culex (Culex species was carried out from August 1992 through December 1993 in a human modified (anthropic environment in the Ribeira Valley, S.Paulo State, Brazil. Culex nigripalpus dominated the catches at several sites and it's tendency to increase in the anthropic environment became quite clear. Nevertheless no high level of synanthropy was demonstrated. So it seems that the mosquito may have a restricted role in natural arbovirus cycles. Nonetheless, Cx. nigripalpus must be considered a potential vector of arboviruses, especially St. Louis encephalitis virus outside dwellings.São relatados os resultados obtidos mediante coletas regulares de adultos de Culex (Culex em ambientes antrópico do Vale do Ribeira, SP, Brasil, no período de agosto de 1992 a dezembro de 1993. Pôde-se evidenciar a dominancia de Culex nigripalpus nas várias coletas efetuadas. Revelou-se claramente a preferência por parte desse mosquito em aumentar sua densidade no ambiente antrópico. Todavia, sua freqüência ao domicílio mostrou-se baixa, revelando fraco grau de sinantropia. Assim sendo, seu papel vetor de arbovirus parece restringir-se à participação no ciclo natural desses agentes infecciosos. Contudo, pode-se considerá-lo como vetor potencial no meio extradomiciliar. Nesse particular, seu papel pode não ser negligenciável, especialmente no que tange à possibilidade de transmissão de encefalite de S.Luís, cujo agente já foi assinalado na região.

  11. Redescription of Cx. corniger Theobald and elevation of Culex (Culex) lactator Dyar and Knab from synonymy based on specimens from Central America (Diptera: Culicidae)

    National Research Council Canada - National Science Library

    Strickman, D; Pratt, J

    1989-01-01

    Culex (Culex) lactator Dyar and Knab is resurrected from synonymy with Culex (Culex) corniger Theobald on the basis of morphological differences in the adult, male genitalia, and fourth-instar larva...

  12. Cloning and expression of cry2Aa from native Bacillus thuringiensis strain SY49-1 and its insecticidal activity against Culex pipiens (Diptera: Culicidae).

    Science.gov (United States)

    Yilmaz, Semih; Azizoglu, Ugur; Ayvaz, Abdurrahman; Temizgul, Ridvan; Atciyurt, Zehra Büşra; Karabörklü, Salih

    2017-04-01

    Bacillus thuringiensis (Berliner) (Bt) is well known for having toxicity against pest insects because of their ability to form endospores and broad-range activity of their parasporal inclusions. In this study, a new member of cry2A gene from previously characterized native B. thuringiensis SY49-1 strain was cloned, expressed and used for its activity against Culex pipiens (Diptera: Culicidae) larvae. The sequence analysis of the cloned cry2A gene revealed that it encodes a polypeptide of 633 aa residues with 99% identity to Cry2Aa protein with expected molecular weight of 70.7 kDa. Bacillus thuringiensis delta-endotoxin nomenclature committee designed our sequence as Cry2Aa18 being a new member of Bt toxins. Bioassays against last instar larvae of C. pipiens indicated that Cry2Aa18 has considerable toxicity with LC50 of 630 μg ml-1. In order to prevent the spread of infectious diseases mediated by C. pipiens, this newly characterized cry2Aa18 gene could constitute as an important biological control tool for controlling mosquito larvae living in freshwater systems and can be used as a good alternative for minimizing the use of chemicals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Evaluation of Andrographis paniculata Burm.f. (Family:Acanthaceae) extracts against Culex quinquefasciatus (Say.) and Aedes aegypti (Linn.) (Diptera:Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu

    2011-03-01

    To investigate the larvicidal and ovicidal efficacy of different extracts of Andrographis paniculata (A. paniculata) against Culex quinquefasciatus (Cx. quinquefasciatus) Say and Aedes aegypti (Ae. aegypti) L. (Diptera: Culicidae). Larvicidal efficacy of the crude leaf extracts of A. paniculata with five different solvents like benzene, hexane, ethyl acetate, methanol and chloroform was tested against the early third instar larvae of Cx. quinquefasciatus and Ae. aegypti. The ovicidal activity was determined against two mosquito species to various concentrations ranging from 50-300 ppm under the laboratory conditions. The benzene, hexane, ethyl acetate, methanol and chloroform leaf extract of A. paniculata was found to be more effective against Cx. quinquefasciatus than Ae. aegypti. The LC(50) values were 112.19, 137.48, 118.67, 102.05, 91.20 ppm and 119.58, 146.34, 124.24, 110.12, 99.54 ppm respectively. Among five tested solvent, methanol and ethyl acetate crude extract was found to be most effective for ovicidal activity against two mosquito species. The extract of methanol and ethyl acetate exerted 100% mortality at 200 ppm against Cx. quinquefasciatus and at 250 ppm against Ae. aegypti. From the results it can be concluded the crude extract of A. paniculata was a potential for controlling Cx. quinquefasciatus and Ae. aegypti mosquitoes. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  14. Larval habitat for the avian malaria vector culex quinquefasciatus (Diptera: Culicidae) in altered mid-elevation mesic-dry forests in Hawai'i

    Science.gov (United States)

    Reiter, M.E.; Lapointe, D.A.

    2009-01-01

    Effective management of avian malaria (Plasmodium relictum) in Hawai'i's endemic honeycreepers (Drepanidinae) requires the identification and subsequent reduction or treatment of larval habitat for the mosquito vector, Culex quinquefasciatus (Diptera: Culicidae). We conducted ground surveys, treehole surveys, and helicopter aerial surveys from 20012003 to identify all potential larval mosquito habitat within two 100+ ha mesic-dry forest study sites in Hawai'i Volcanoes National Park, Hawai'i; 'Ainahou Ranch and Mauna Loa Strip Road. At 'Ainahou Ranch, anthropogenic sites (43%) were more likely to contain mosquitoes than naturally occurring (8%) sites. Larvae of Cx. quinquefasciatus were predominately found in anthropogenic sites while Aedes albopictus larvae occurred less frequently in both anthropogenic sites and naturally-occurring sites. Additionally, moderate-size (???20-22,000 liters) anthropogenic potential larval habitat had >50% probability of mosquito presence compared to larger- and smaller-volume habitat (malaria, may be controlled by larval habitat reduction in the mesic-dry landscapes of Hawai'i where anthropogenic sources predominate.

  15. Ovicidal, larvicidal and adulticidal properties of Asparagus racemosus (Willd.) (Family: Asparagaceae) root extracts against filariasis (Culex quinquefasciatus), dengue (Aedes aegypti) and malaria (Anopheles stephensi) vector mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2014-04-01

    Several diseases are associated to the mosquito-human interaction. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The present investigation was undertaken to study the ovicidal, larvicidal and adulticidal activities of crude hexane, ethyl acetate, benzene, chloroform and methanol extracts of root of Asparagus racemosus were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi (Diptera: Culicidae). The mean percent hatchability of the eggs was observed after 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the methanol extract showed the highest ovicidal activity. The methanol extract of Asparagus racemosus against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi exerted 100% mortality (zero hatchability) at 375, 300 and 225 ppm, respectively. Control eggs showed 99-100% hatchability. The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in methanol extract of root of Asparagus racemosus against the larvae of Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi with the LC50 and LC90 values were 115.13, 97.71 and 90.97 ppm and 210.96, 179.92, and 168.82 ppm, respectively. The adult mortality was observed after 24 h recovery period. The plant crude extracts showed dose-dependent mortality. At higher concentrations, the adult showed restless movement for some times with abnormal wagging and then died. Among the extracts tested, the highest adulticidal activity was observed in

  16. Larvicidal potential of carvacrol and terpinen-4-ol from the essential oil of Origanum vulgare (Lamiaceae) against Anopheles stephensi, Anopheles subpictus, Culex quinquefasciatus and Culex tritaeniorhynchus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Hoti, S L; Benelli, Giovanni

    2016-02-01

    Mosquito-borne diseases represent a deadly threat for millions of people worldwide. However, the use of synthetic insecticides to control Culicidae may lead to resistance, high operational costs and adverse non-target effects. Nowadays, plant-borne mosquitocides may serve as suitable alternative in the fight against mosquito vectors. In this study, the mosquito larvicidal activity of Origanum vulgare (Lamiaceae) leaf essential oil (EO) and its major chemical constituents was evaluated against the malaria vectors Anopheles stephensi and An. subpictus, the filariasis vector Culex quinquefasciatus and the Japanese encephalitis vector Cx. tritaeniorhynchus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the essential oil of O. vulgare contained 17 compounds. The major chemical components were carvacrol (38.30%) and terpinen-4-ol (28.70%). EO had a significant toxic effect against early third-stage larvae of An. stephensi, An. subpictus, Cx. quinquefasciatus and Cx. tritaeniorhynchus, with LC50 values of 67.00, 74.14, 80.35 and 84.93 μg/ml. The two major constituents extracted from the O. vulgare EO were tested individually for acute toxicity against larvae of the four mosquito vectors. Carvacrol and terpinen-4-ol appeared to be most effective against An. stephensi (LC50=21.15 and 43.27 μg/ml, respectively) followed by An. subpictus (LC50=24.06 and 47.73 μg/ml), Cx. quinquefasciatus (LC50=26.08 and 52.19 μg/ml) and Cx. tritaeniorhynchus (LC50=27.95 and 54.87 μg/ml). Overall, this research adds knowledge to develop newer and safer natural larvicides against malaria, filariasis and Japanese encephalitis mosquito vectors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Atividade predatória de Helobdella triserialis lineata (Hirudinea: Glossiphonidae sobre formas imaturas de Aedes fluviatilis e Culex quinquefasciatus (Diptera: Culicidae em laboratório Predatory activity of Helobdella triserialis lineata (Hirudinea: Glossiphonidae on immature forms of Aedes ftuviatilis and Culex quinquefasciatus (Diptera: Culicidae in the laboratory

    Directory of Open Access Journals (Sweden)

    Rotraut Anna Gertrud Bohlmann Cônsoli

    1984-10-01

    Full Text Available Foi avaliada a atividade predatória, em laboratório, de Helobdella triserialis lineata (Hirudinea: Glossiphonidae sobre ovos, larvas e pupas de Aedes fluviatilis e Culex quinquefasciatus (Diptera: Culicidae, bem como a influência da presença desses hirudíneos sobre o comportamento de oviposição das fêmeas das duas espécies de mosquitos. Experimentos adicionais foram feitos testando a influência da profundidade da água e da sua salinidade sobre a capacidade predatória dos hirudíneos. Nas condições do experimento, foi observada predação de larvas e pupas, porém não de ovos das duas espécies de dípteros. Número estatisticamente menor de desovas foi depositado por fêmeas de Cx. quinquefasciatus em recipientes que continham hirudíneos, não ocorrendo o mesmo com fêmeas de Ae. fluviatilis. As diferentes profundidades de água testadas não interferiram na atividade predatória de H. t. lineata e somente em concentrações acima de 3% de NaCl essa atividade mostrou-se bastante diminuída.Experiments were conducted to determine the predatory activity of Helobdella triserialis lineata (Hirudinea: Glossiphonidae on eggs, larvae and pupae of Aedes fluviatilis and Culex quinquefasciatus (Diptera: Culicidae in the laboratory, The influence of the leeches on selection, of ovipositing sites by the females of both species of mosquitoes, as well as the role of salinity and water depth in relation to predation were investigated. Larvae and pupae of both species of mosquitoes were efficiently predated, but eggs were not touched. A significantly lower number of eggmasses of Cx. quinquefasciatus were deposited on water containing leeches, but the same did not occur with Ae. fluviatilis. The different depths of water investigated did not interfere with predation and only at concentrations above 3% NaCl was predation considerably diminished.

  18. Predation and control efficacies of Misgurnus mizolepis (Cypriniformes: Cobitidae) toward Culex pipiens molestus (Diptera: Culicidae) and fish toxicity of temephos in laboratory and septic tank conditions.

    Science.gov (United States)

    Chae, Seong Chun; Kwon, Young Hyun; Min, Kyung Il; Kim, Hyung Soo; Kim, Nam-Jin; Kim, Jun-Ran; Son, Bong Gi; Ahn, Young-Joon

    2014-07-01

    Culex pipiens molestus Forskal (Diptera: Culicidae) is the dominant mosquito species in septic tanks in South Korea. An assessment was made of the biological control potential of mud loaches, Misgurnus mizolepis Günther (Cypriniformes: Cobitidae), toward Cx. p. molestus larvae in laboratory and septic tanks. Results were compared with those of temephos 20% emulsifiable concentrate. In laboratory tests, all mud loaches survived on sedimentation chamber- and effluent chamber-collected water of aerobic septic tanks (ASTs), whereas all mud loaches died within 3-12 h after introduction into sedimentation chamber- and effluent chamber-collected water of anaerobic septic tanks, Gill hyperplasia and hemorrhages at the bases of pectoral fins were detected in all dead mud loaches. These appeared to have been caused by bacterial disease, rather than the physical and chemical characteristics of the septic tank water. A mud loach consumed an average range of 1,072-1,058 larvae of Cx. p. molestus in the AST water at 24 h. At the manufacturer's recommended rate (10 ml/ton) in the AST water, the temephos formulation did not cause fish mortality. In the AST experiment, predation of mosquito larvae by mud loaches at a release rate of one fish per 900 mosquito larvae resulted in complete mosquito control from the third day after treatment throughout the 18-wk survey period, compared with temephos 20% emulsifiable concentrate-treated AST water (reduction rate, 40% at 28 days after treatment). Reasonable mosquito control in aerobic septic tanks can be achieved by mosquito breeding season stocking of a rate of one mud loach per 900 mosquito larvae.

  19. Evaluation of Two Entomopathogenic Fungi for Control of Culex quinquefasciatus (Diptera: Culicidae) in Underground Storm Drains in the Coachella Valley, California, United States.

    Science.gov (United States)

    Popko, David A; Henke, Jennifer A; Mullens, Bradley A; Walton, William E

    2017-12-22

    Commercially available formulations of two entomopathogenic fungi, Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Clavicipitaceae) and Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitaceae), were assessed for control of Culex quinquefasciatus Say (Diptera: Culicidae) in underground storm drain systems (USDS) in the Coachella Valley of southern California. Each of three treatments, the two fungi or a water control, was applied to 1 m2 of vertical wall at eight USDS sites in spring and autumn of 2015. Fungal infectivity and lethality were assessed at 1 d and 1, 2, and 4 wk post-application. Overnight bioassays using adult lab-reared female mosquitoes were carried out on the treated USDS wall areas and then mosquitoes were held in the laboratory for up to 21 d to allow fungal infections to be expressed. Postmortem fungal sporulation was assessed up to 2 wk at 100% humidity. Mosquito-fungal interactions also were assessed in bioassays of the three treatments on filter paper exposed to USDS conditions during autumn. Metarhizium anisopliae killed mosquitoes faster than B. bassiana; nevertheless, both freshly applied formulations caused greater than 80% mortality. Fungal persistence declined significantly after 1 wk under USDS conditions, but some infectivity persisted for more than 4 wk. Beauveria bassiana was more effective against Cx. qinquefasciatus in the spring, while M. anisopliae was more effective in the cooler conditions during autumn. USDS environmental conditions (e.g., temperature, relative humidity, standing water) influenced fungal-related mortality and infection of Cx. quinquefasciatus. The utility of these fungal formulations for mosquito abatement in the Coachella Valley and implications for fungal control agents in USDS environments are discussed. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Efficacy of essential oils of aromatic plants as larvicide for the management of filarial vector Culex quinquefasciatus Say (Diptera: Culicidae with special reference to Foeniculum vulgare

    Directory of Open Access Journals (Sweden)

    Inder Singh Rana

    2012-06-01

    Full Text Available Objective: To evaluate the larvicidal activity of essential oils derived from ten aromatic plants with special reference to Foeniculum vulgare (F. vulgare against early fourth instar larvae of Culex quinquefasciatus (Cx. quinquefasciatus Say (Diptera: Culicidae. Methods: Essential oils were extracted from plant materials through hydro distillation and efficacy was determined through bioassay method. Two of the effective oils were evaluated further for the determination of their LC 50 and LT50 values based on Probit analysis.Essential oils of one plant was analyzed through TLC and HPLC. Results: Most of the essential oils caused 100% mortality within 120 min at 250 ppm. Oil of Tagetes patula (T. patula and F. vulgare gave more than 90% mortality within 40 min. LC 50 values calculated after 60 min of treatment were (84.80 暲 7.65 and (24.69 暲 1.24 ppm for T. patula and F. vulgare respectively. At the same exposure period positive control temephos yielded (22.13暲2.39 ppm LC50 value. At 50 ppm T. patula, F. vulgare and temephos exhibited LT 50 values (113.71 暲 10.29, (11.02 暲 3.31 and (38.15 暲 5.90 mins respectively. Presence of high quantity of trans anethole in the essential oils of F. vulgare was confirmed by TLC and HPLC results. Conclusions: Present study indicates that essential oils of spices/aromatic medicinal plants particularly F. vulgare and T. patula carry huge potential as a mosquito larvicide. This potential could be exploited for the development of safer and effective botanical mosquito larvicidal tool for the management of Cx. quinquefasciatus.

  1. Genetic Diversity and Population Genetics of Mosquitoes (Diptera: Culicidae: Culex spp. from the Sonoran Desert of North America

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    Edward Pfeiler

    2013-01-01

    Full Text Available The population genetics and phylogenetic relationships of Culex mosquitoes inhabiting the Sonoran Desert region of North America were studied using mitochondrial DNA and microsatellite molecular markers. Phylogenetic analyses of mitochondrial cytochrome c oxidase subunit I (COI from mosquitoes collected over a wide geographic area, including the Baja California peninsula, and mainland localities in southern Arizona, USA and Sonora, Mexico, showed several well-supported partitions corresponding to Cx. quinquefasciatus, Cx. tarsalis, and two unidentified species, Culex sp. 1 and sp. 2. Culex quinquefasciatus was found at all localities and was the most abundant species collected. Culex tarsalis was collected only at Tucson, Arizona and Guaymas, Sonora. The two unidentified species of Culex were most abundant at Navojoa in southern Sonora. Haplotype and nucleotide diversities in the COI gene segment were substantially lower in Cx. quinquefasciatus compared with the other three species. Analysis of molecular variance revealed little structure among seven populations of Cx. quinquefasciatus, whereas significant structure was found between the two populations of Cx. tarsalis. Evidence for an historical population expansion beginning in the Pleistocene was found for Cx. tarsalis. Possible explanations for the large differences in genetic diversity between Cx. quinquefasciatus and the other species of Culex are presented.

  2. Genetic Diversity and Population Genetics of Mosquitoes (Diptera: Culicidae: Culex spp.) from the Sonoran Desert of North America

    Science.gov (United States)

    Pfeiler, Edward; Flores-López, Carlos A.; Mada-Vélez, Jesús Gerardo; Escalante-Verdugo, Juan; Markow, Therese A.

    2013-01-01

    The population genetics and phylogenetic relationships of Culex mosquitoes inhabiting the Sonoran Desert region of North America were studied using mitochondrial DNA and microsatellite molecular markers. Phylogenetic analyses of mitochondrial cytochrome c oxidase subunit I (COI) from mosquitoes collected over a wide geographic area, including the Baja California peninsula, and mainland localities in southern Arizona, USA and Sonora, Mexico, showed several well-supported partitions corresponding to Cx. quinquefasciatus, Cx. tarsalis, and two unidentified species, Culex sp. 1 and sp. 2. Culex quinquefasciatus was found at all localities and was the most abundant species collected. Culex tarsalis was collected only at Tucson, Arizona and Guaymas, Sonora. The two unidentified species of Culex were most abundant at Navojoa in southern Sonora. Haplotype and nucleotide diversities in the COI gene segment were substantially lower in Cx. quinquefasciatus compared with the other three species. Analysis of molecular variance revealed little structure among seven populations of Cx. quinquefasciatus, whereas significant structure was found between the two populations of Cx. tarsalis. Evidence for an historical population expansion beginning in the Pleistocene was found for Cx. tarsalis. Possible explanations for the large differences in genetic diversity between Cx. quinquefasciatus and the other species of Culex are presented. PMID:24302868

  3. Sampling gravid Culex quinquefasciatus (Diptera: Culicidae) in Tanzania with traps baited with synthetic oviposition pheromone and grass infusions

    NARCIS (Netherlands)

    Mboera, L.E.G.; Takken, W.; Mdira, K.Y.; Pickett, J.A.

    2000-01-01

    The effectiveness of traps baited with (5R,6S)-6-acetoxy-5-hexadecanolide (the synthetic oviposition pheromone) and grass infusions in sampling a population of gravid Culex quinquefasciatus Say was conducted in Muheza, Northeast Tanzania. A counterflow geometry (CFG) trap baited with pheromone and

  4. Baseline Insecticide Susceptibility Screening Against Six Active Ingredients for Culex and Aedes (Diptera: Culicidae) Mosquitoes in the United States.

    Science.gov (United States)

    Richards, Stephanie L; Balanay, Jo Anne G; Fields, Melinda; Vandock, Kurt

    2017-05-01

    Mosquitoes may develop resistance to insecticide active ingredients (AI). Thus, mosquitoes should be tested for resistance to confirm efficacy of insecticide-based control, inform management decisions, and protect public and environmental health. Our objectives were to determine a baseline of resistance for six AIs used in mosquito control in the United States to assess how resistance differs between mosquito collection location, AI, and mosquito species (container-ovipositing Aedes and Culex that may oviposit in containers or other sources). Field-collected eggs from 26 mosquito populations of five different species or hybrid species (Aedes albopictus Say, Aedes triseriatus Say, Culex pipiens L., Culex quinquefasciatus Say, Culex pipiens/quinquefasciatus) were obtained from four regions across the United States. Centers for Disease Control and Prevention bottle bioassays were used to determine baseline resistance and susceptibility status for six AIs (bifenthrin, deltamethrin, etofenprox, malathion, permethrin, and phenothrin). World Health Organization guidelines were used to classify mosquitoes as susceptible (98-100% mortality at diagnostic time [DT]), possibly resistant (80-97% mortality at DT), or resistant (Aedes spp. mosquitoes were less likely to exhibit resistance, compared with Culex spp. mosquitoes. A high degree of resistance to etofenprox and malathion was observed (4-26-fold greater resistance to these two AIs compared with the other examined AIs). Baseline data on resistance and susceptibility for mosquitoes exposed to commonly used insecticides may help us evaluate resistance trends and highlight the importance of assessing local resistance trends before insecticide-based control measures are implemented. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Morphometric geometric study of wing shape in Culex quinquefasciatus Say (Diptera: Culicidae) from Tamil Nadu, India

    OpenAIRE

    K. Manimegalai; M. Arunachalam; R. Udayakumari

    2009-01-01

    The morphometric geometric study was carried out in 10 males and 10 females of Culex quinquefasciatus. There are 23 landmarks corresponding to points at which wing veins either branch or intersect the margin of the wing. Relative warp analysis has been proved to be very efficient in distinguishing the variation of shape in male and female wings. The multivariate analysis of co-variance (MANCOVA) showed a clear separation of the male and female wings.

  6. Larvicidal activity of Ageratum houstonianum Mill. (Asteraceae leaf extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae

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    Samuel Tennyson

    2015-06-01

    Full Text Available Objective: To evaluate the larvicidal activity of Ageratum houstonianum (A. houstonianum crude leaf extracts against the immatures of vector mosquitoes. Methods: Bioassays were performed in the laboratory with hexane, ethyl acetate and methanol crude leaf extracts of A. houstonianum at concentrations of 62.5, 125, 250, 500, 1 000, 2 000, 4 000 and 8 000 mg/L against the third instar larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. Results: Poor larvicidal activity was observed. The lowest LC50 value was noted in ethyl acetate extract against all three vector mosquito species studied and was 3 377.84, 1 952.12 and 3 558.32 mg/L respectively after 24 h. The effect of toxicity was also manifested in a shorter period when compared to the other extracts viz., hexane and methanol. In Anopheles stephensi, more than 80% mortality was however observed at higher concentrations, after 24 h exposure in all the three extracts. In Aedes aegypti and Culex quinquefasciatus, this was observed by 3 and 24 h respectively in ethyl acetate extract. Conclusions: Screening of other parts of A. houstonianum with other solvents from different places for its larvicidal activity is recommended.

  7. Ovicidal activity of Ageratum houstonianum Mill. (Asteraceae leaf extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Samuel Tennyson

    2015-03-01

    Full Text Available Objective: To study the ovicidal activity of Ageratum houstonianum (A. houstonianum leaf extracts against the eggs of vector mosquitoes and to develop additional tools for the control of mosquito-borne diseases. Methods: The ovicidal activity of crude hexane, ethyl acetate and methanol leaf extracts of A. houstonianum were assayed for their toxicity against the eggs of three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus at concentrations of 2.5, 5.0, 10.0 and 20.0 mg/L of the crude extract. Results: All extracts showed activity. The minimum concentration at which maximum egg mortality rate of 80% and above obtained was 10.0 mg/L in the case of methanol and ethyl acetate against Anopheles stephensi and Aedes aegypti respectively and 5.0 mg/L in ethyl acetate extract against Culex quinquefasciatus. One hundred per cent egg mortality was obtained only in ethyl acetate extract at 20.0 mg/L against Aedes aegypti. Conclusions: The crude leaf extracts of A. houstonianum did not exhibit potential ovicidal activity against the vector species studied. Among the crude leaf extracts tested, the activity of ethyl acetate extract was more effective. More research on the screening of phytochemicals as a potential ovicidal agent is warranted to add more tools in the control of mosquitoes.

  8. Latent effect of gamma irradiation on reproductive potential and ultrastructure of males' testes of Culex pipiens (Diptera; Culicidae

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    Mostafa I. Hassan

    2017-01-01

    Full Text Available Laboratory male pupae of Culex pipiens were exposed to 23, 41, 74 and 128 Gy doses of gamma radiation according to the LD25, LD50, LD75 and LD90 calculation, respectively. The inherited deleterious effects of gamma radiation were observed in the F1, F2 and F3 generations. Levels of sterility index in the F1 and F2 were higher than those of untreated control but in the F3 generation there was a semi-sterility compared with the control. Ultrastructure of normal males' testes of C. pipiens was studied using transmission electron microscopy. Histopathological responses were observed in the irradiated testes of C. pipiens. Gamma radiation had greatly affected the testes, such as (i rupture, necrosis, degeneration and small vacuoles were reported in the testicular wall (ii an abnormal distribution of the developmental stages of spermatogonia and spermatocytes leading to a general decrease in the rate of spermatogenesis; and (iii deformity of sperm inhibitting the movements and the fertility of the sperm led to the decrease in the reproductive potential of C. pipiens. Consequently, these radiation doses are consistent with those used in the already established Sterile Insect Technique (SIT programmes against Culex pipiens.

  9. The Effect of West Nile Virus Infection on the Midgut Gene Expression of Culex pipiens quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Smartt, Chelsea T; Shin, Dongyoung; Anderson, Sheri L

    2016-12-19

    The interaction of the mosquito and the invading virus is complex and can result in physiological and gene expression alterations in the insect. The association of West Nile virus (WNV) and Culex pipiens quinquefasciatus mosquitoes results in measurable changes in gene expression; 22 gene products were shown previously to have altered expression. Sequence analysis of one product, CQ G1A1, revealed 100% amino acid identity to gram negative bacteria binding proteins (CPQGBP) in Cx. p. quinquefasciatus, Aedes aegypti (70%) and Anopheles gambiae (63%) that function in pathogen recognition. CQ G1A1 also was differentially expressed following WNV infection in two populations of Cx. p. quinquefasciatus colonized from Florida with known differences in vector competence for WNV and showed spatial and temporal gene expression differences in midgut, thorax, and carcass tissues. These data suggest gene expression of CQ G1A1 is influenced by WNV infection and the WNV infection-controlled expression differs between populations and tissues.

  10. Evaluation of a nonanal-trimethylamine lure for collection of Culex quinquefasciatus (Diptera: Culicidae) in gravid traps.

    Science.gov (United States)

    Irish, S R; Moore, S J; Bruce, J; Birkett, M A; Cameron, M M

    2013-05-01

    Gravid traps are useful tools for monitoring vector-borne pathogens in mosquitoes, particularly for those pathogens transmitted by Culex quinquefasciatus Say. One of the primary challenges in the use of gravid traps is the necessity of the inclusion of an oviposition attractant, usually an infusion of organic material, which changes in attractiveness over time. However, a standardized lure, using nonanal and trimethylamine (N + TMA), has been developed and is commercially available. The N + TMA lure was tested against grass infusion and tap water in Tanzania, where Cx. quinquefasciatus is a vector of lymphatic filariasis. Traps baited with grass infusion collected significantly more mosquitoes than N + TMA-baited traps, which collected significantly more than traps baited with tap water. The advantages and disadvantages of the standardized lure are discussed.

  11. [Resistance to the organophosphate insecticides temephos and malathion in Culex pipiens L. (Diptera, Culicidae) from the Adriatic coast near Friuli].

    Science.gov (United States)

    Zamburlini, R; Bellantone, P

    1993-12-01

    Susceptibility to organophosphorus insecticides Temephos and Malathion was tested in Culex pipiens L. larvae from Friuli Adriatic coast (North-East of Italy). The samples were collected in various sites of three zones with different intensity of insecticidal treatments. Tests were made following the W.H.O. recommendations. The tests were made on larval samples which were exposed for 24 hours to ascending concentrations of each insecticide. From the observed percentage mortalities the LC50 and LC90 values were calculated. The resistance ratio was obtained comparing the CL50 values with reference CL50 values provided by the W.H.O. The obtained data suggest the existence of Cx. pipiens populations resistant to the tested chemicals in the most intensively treated touristic zone (Lignano Sabbiadoro). The samples collected in an agricultural zone with no mosquito control treatments showed a slight reduced susceptibility to the tested compounds.

  12. Resistance to Lysinibacillus sphaericus and Other Commonly Used Pesticides in Culex pipiens (Diptera: Culicidae) from Chico, California.

    Science.gov (United States)

    Su, Tianyun; Thieme, Jennifer; Ocegueda, Chris; Ball, Matthew; Cheng, Min-Lee

    2017-12-19

    Bacillus sphaericus Neide, recently renamed as Lysinibacillus sphaericus Meyer and Neide, is a spore-forming bacterium that possesses various levels of larvicidal activity, depending on the strains, against some mosquito species. Products based on most active strains such as 2362, 2297, 1593, C3-41 that bear binary toxins, as well as mosquitocidal toxins at various levels, have been developed to combat mosquito larvae worldwide. Resistance in wild Culex mosquito populations has been reported since 1994 from France, Brazil, India, China, Thailand, and Tunisia. Laboratory studies to evaluate resistance development risk have been conducted by many groups of scientists worldwide. Products based on L. sphaericus strain 2362 were registered in the United States in 1990s, and their use for mosquito control has been increased considerably since invasion of West Nile virus. This report documents the first occurrence of high-level resistance to L. sphaericus in a natural population of Culex pipiens L. in Chico, CA, where resistance ratio was 537.0 at LC50 and 9,048.5 at LC90 when compared with susceptible laboratory colony of the same species. Susceptibility profile to other groups of pesticides with different modes of action was also determined. Various levels of resistance or tolerance were noticed to abamectin, pyriproxyfen, permethrin, and indoxacarb. Resistance management and susceptibility monitoring strategies are discussed and recommended. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Control of human filarial vector, Culex quinquefasciatus Say 1823 (Diptera: Culicidae) through bioactive fraction of Cayratia trifolia leaf.

    Science.gov (United States)

    Chakraborty, Sumanta; Singha, Someshwar; Bhattacharya, Kuntal; Chandra, Goutam

    2013-12-01

    To investigate the mosquito larvicidal activity of Cayratia trifolia (L.) Domin (Vitaceae: Vitales) (C. trifolia) which is distributed in many parts of India with medicinal properties as vector control is facing threat due to the emergence of resistance to synthetic insecticides. Young and mature leaves of C. trifolia were investigated for larvicidal activity against 3rd instars larvae of Culex quinquefasciatus in different seasons throughout the year. The active fractions were extracted using six different solvents in a non-polar to polar fashion viz petroleum-ether, benzene, chloroform: methanol (1:1 v/v), acetone, absolute alcohol and distilled water. Dose dependent mortality was recorded against each solvent extract. Determination of LD50 and LD90 were executed through log-probit analysis using the most bioactive fraction. The fluctuations in mortality were statistically co-related through ANOVA analyses concerning different seasons and types of leaves as random variables. Justification of larvicidal activity was established through student's t-test. Costing effects were evaluated on the non-target water fauna under laboratory conditions. Thin layer chromatographic techniques were performed for phytochemical analysis and categorization of chemical personality of the active fractions using the most effective solvent extract following standard methods. Significant variations in mortality rate were noted with respect to the type of leaves (mature and senescence), concentration of leaf extract and between seasons. The water extract among all the solvent extracts was found to induce cent percent mortality at 50 mg/L in test mosquito species within 24 h with a LD50 and LD90 value of 10.70 mg/L and 27.64 mg/L respectively. No significant mortality was recorded in non-target water population. Chromatographic analyses of the water extract revealed the presence of steroids, triterpene glycosides, essential oil, phenolics and diterpenes as secondary phytochemicals. Water

  14. Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus in four strains of Culex tarsalis (Diptera: Culicidae: an immunocytochemical study

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    Neira Oviedo MV

    2011-04-01

    Full Text Available Marco V Neira Oviedo1,2, William S Romoser1, Calvin BL James1, Farida Mahmood3, William K Reisen31Tropical Disease Institute, Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, Athens, OH, USA; 2Oxitec Inc, Oxford, England; 3Center for Vectorborne Diseases, School of Veterinary Medicine, University of California, Davis, CA, USABackground: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV, we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion.Methods: Using immuno-stained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains – Coachella Valley, Riverside County (COAV and Kern National Wildlife Refuge (KNWR; and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP, and WEEV resistance (WR.Results and conclusions: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth

  15. Culex (Culiciomyia) sasai (Diptera: Culicidae), senior synonym of Cx. spiculothorax and a new country record for Bhutan.

    Science.gov (United States)

    Phanitchakun, Thanari; Wilai, Parinya; Saingamsook, Jassada; Namgay, Rinzin; Drukpa, Tobgyel; Tsuda, Yoshio; Walton, Catherine; Harbach, Ralph E; Somboon, Pradya

    2017-07-01

    Culex (Culiciomyia) spiculothorax was described from Thailand based on the presence of spiculation on the thorax of larvae. Adult females are characterized but are indistinguishable from those of related species, such as Cx. pallidothorax. Phylogenetic analysis of mitochondrial oxidase subunit I (COI) sequences revealed that specimens identified as Cx. spiculothorax from Thailand, Japan and Bhutan form a single clade with Cx. sasai from Japan (Kimura 2-parameter genetic distances 0-0.9%) that is clearly distinct from clades comprised of other species of subgenus Culiciomyia. Attempts to collect Cx. sasai from several locations in Japan were unsuccessful - only larvae with thoracic vesicular-like spicules identified as Cx. spiculothorax were collected. Careful examination of specimens collected near the type locality of Cx. sasai revealed the presence of spicules on the thorax. Based on these findings, Cx. spiculothorax is formally synonymized with Cx. sasai, which replaces the former as the species present in Thailand and is a new country record for Bhutan. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Feeding patterns of molestus and pipiens forms of Culex pipiens (Diptera: Culicidae) in a region of high hybridization.

    Science.gov (United States)

    Gomes, Bruno; Sousa, Carla A; Vicente, José L; Pinho, Leonor; Calderón, Isabel; Arez, Eliane; Almeida, António Pg; Donnelly, Martin J; Pinto, João

    2013-04-11

    Two biological forms of the mosquito Culex pipiens s.s., denoted pipiens and molestus, display behavioural differences that may affect their role as vectors of arboviruses. In this study, the feeding patterns of molestus and pipiens forms were investigated in Comporta (Portugal), where high levels of inter-form admixture have been recorded. Indoor and outdoor mosquito collections were performed in the summer of 2010. Collected Cx. pipiens s.l. females were molecularly identified to species and form by PCR and genotyped for six microsatellites. The source of the blood meal in post-fed females was determined by ELISA and mitochondrial DNA sequencing. The distribution of the forms differed according to the collection method. The molestus form was present only in indoor collections, whereas pipiens and admixed individuals were sampled both indoors and outdoors. In both forms, over 90% of blood meals were made on avian hosts. These included blood meals taken from Passeriformes (Passer domesticus and Turdus merula) by females caught resting inside domestic shelters. Genetic structure and blood meal analyses suggest the presence of a bird biting molestus population in the study area. Both forms were found to rest indoors, mainly in avian shelters, but at least a proportion of females of the pipiens form may bite outdoors in sylvan habitats and then search for anthropogenic resting sites to complete their gonotrophic cycle. This behaviour may potentiate the accidental transmission of arboviruses to humans in the region.

  17. Repellent activity of Ageratum houstonianum Mill. (Asteraceae leaf extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Samuel Tennyson

    2012-12-01

    Full Text Available Objective: To determine the repellent activity of hexane, ethyl acetate and methanol crude extracts of Ageratum houstonianum (A. houstonianum leaves against adult Anopheles stephensi (An. stephensi, Aedes aegypti (Ae. aegypti and Culex quinquefasciatus (Cx. quinquefasciatus mosquitoes. Methods: Bioassay on laboratory reared Swiss albino mice by topical application at a fixed concentration of 0.01 per cent with coconut oil as a base. Results: Crude leaf extracts of A. houstonianum in combination with coconut oil repelled vector mosquitoes. Maximum protection for a period of 11.30 h was obtained against Cx. quinquefasciatus and An. stephensi when treated with methanol and hexane extracts followed by 8.30 h against Ae. aegypti in methanol extract. Amongst the three extracts, methanol extract gave the maximum protection of 95.0% against Cx. quinquefasciatus. Hexane and ethyl acetate extracts gave a maximum of 93.4% protection against An. stephensi. Conclusions: The crude extracts of A. houstonianum leaves in combination with coconut oil showed repellent activity with repellent quotient ranging from 0.6 to 0.9.

  18. Evaluation of larvicidal efficacy of Cleome viscosa L. (Capparaceae aerial extracts against Culex quinquefasciatus Say (Diptera: Culicidae

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    Murugesan Sakthivadivel

    2014-09-01

    Full Text Available Objective: To evaluate the larvicidal efficacy of crude petroleum ether, chloroform, acetone and aqueous aerial extracts of Cleome viscosa against the filarial vector, Culex quinquefasciatus. Methods: Standard World Health Organization protocols with minor modifications was adopted for the larvicidal bioassay. Larvicidal activity of exyracts was evaluated at concentrations of 62.5, 125, 250, 500 and 1 000 mg/L. Larval mortality was observed after 24 and 48 h. Results: Amongst the solvent extracts tested, petroleum ether exhibited the highest larvicidal activity and LC50 values was 52.62 and 43.16 mg/L followed by acetone, aqueous and chloroform extract with LC 50 values of 328.64 and 280.58; 493.44 and 298.76; 509.27 and 434.40 mg/L after 24 and 48 h respectively. Conclusions: Further investigations are needed to explore the larvicidal activity of the petroleum ether aerial extract of this plant against a wide range of mosquito species and also the active ingredient(s of the extract responsible for larvicidal activity should be identified.

  19. Different toxicity of the novel Bacillus thuringiensis (Bacillales: Bacillaceae) strain LLP29 against Aedes albopictus and Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Zhang, Lingling; Tang, Baozhen; Huang, Enjiong; Huang, Zhipeng; Liu, Zhaoxia; Huang, Tianpei; Gelbic, Ivan; Guan, Xiong; Xu, Lei

    2013-06-01

    Bacillus thuringiensis (Bt) (Berliner) strain LLP29 produces a crystal protein Cyt1Aa6 toxic to mosquito vectors of human diseases. However, the susceptibility of Culex quinquefasciatus (Say) in the current study was 8.25 times higher than that of Aedes albopictus (Skuse) with this single protein Cyt1Aa6 purified from LLP29. To understand the mechanism of the novel mosquitocidal protein, the binding characteristic of brush border membrane vesicles from the two tested mosquitoes was investigated. Enzyme-linked immunosorbent assay showed that Cyt1Aa6 bound to the two mosquitoes' brush border membrane vesicles. However, the titer of Ae. albopictus was a little higher than that of Cx. quinquefasciatus, with 3.21 and 2.91, respectively. Ligand Western blot analysis showed Cyt1Aa6 toxin specifically bound to the same three proteins (i.e., 68, 54, and 26 kDa) in the two mosquitoes, but one another protein, approximately to 37 kDa, could just be detected in Cx. quinquefasciatus. However, little difference was found in the test of immunohistochemistry. Cyt1Aa6 was detected in the midguts of both mosquitoes with histopathological changes. It would of great importance to the knowledge of the novel toxin against to Cx. quinquefasciatus and Ae. albopictus.

  20. Larvicidal activity of pectolinaringenin from Clerodendrum phlomidis L. against Culex quinquefasciatus Say and Aedes aegypti L. (Diptera: Culicidae).

    Science.gov (United States)

    Muthu, Chellaiah; Reegan, Appadurai Daniel; Kingsley, Selvadurai; Ignacimuthu, Savarimuthu

    2012-09-01

    Larvicidal activity of 12 fractions and a compound of chloroform extract of Clerodendrum phlomidis L. (Lamiaceae) was assayed for their toxicity against the early fourth-instar larvae of the filarial vector Culex quinquefasciatus Say and dengue vector Aedes aegypti L. The fractions were tested at 100-, 50-, 25- and 12.5-ppm concentrations. The compound pectolinaringenin was tested at 5-, 2.5-, 1.0- and 0.5-ppm concentrations. Among the different fractions, fraction 5 recorded the lowest LC(50) and LC(90) values of 5.02, 61.63 ppm and 32.86, 73.62 ppm against C. quinquefasciatus and A. aegypti, respectively. The compound pectolinaringenin showed the lowest LC(50) and LC(90) values of 0.62, 2.87 ppm and 0.79, 5.31 ppm against C. quinquefasciatus and A. aegypti, respectively. This is the first report on the mosquito larvicidal activity of the isolated compound pectolinaringenin from C. phlomidis. The results of this study show that the chloroform extract of C. phlomidis can be used as a potent source and pectolinaringenin as a new natural mosquito larvicidal agent.

  1. REPELLENT EFFECT OF OCIMUM BASILICUM AND GLYCYRRHIZA GLABRA EXTRACTS AGAINST THE MOSQUITO VECTOR, CULEX PIPIENS (DIPTERA: CULICIDAE).

    Science.gov (United States)

    Hassan, Mostafa I; Hammad, Kotb M; Saeed, Saeed M

    2015-08-01

    Essential or volatile oils of plants have been variously reported to have many medicinal applications. Methanol, acetone and petroleum ether extracts of Ocimum basilicum and Glycyrrhiza glabra were screened for their repellency effect against Culex pipiens mosquito. The repellent action of the present plants extracts were varied depending on the solvent used and dose of extract. Methanol extract of O. basilicum exhibited the lowest repellent activity as it recorded 77.4% at 6.7mg/cm2. The petroleum ether and acetone extract of 0. basilicum showed repellency of 98.1 & 84.6% respectively, at dose of 6.7mg/cm2, while methanolic extract of G. glabra recorded 73.8 & 50.3% at dose of 6.7 &1.7mg/cm2 respectively, the petroleum ether and acetone extract of G. glabra showed repellency of 76.3 & 81.6%, respectively at dose of 6.7mg/cm2, compared with the commercial formulation, N.N. diethyl toulamide (DEET) which exhibited 100% repellent action at dose of 1.8mg/cm2, respectively. The results may contribute to design an alternative way to control mosquitoes currently based on applications of synthetic insecticides. These extracts could be developed commercially as an effective personal protection meaure against mosquito bites and thus to control diseases caused by mosquito-borne pathogens.

  2. Toxicity of Amorphigenin from the Seeds of Amorpha fruticosa against the Larvae of Culex pipiens pallens (Diptera: Culicidae

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    Yaping Liang

    2015-02-01

    Full Text Available The larvicidal activity of the crude petroleum ether, ethyl acetate, acetone, chloroform and ethanol extracts of Amorpha fruticosa seeds was individually assayed for toxicity against the early fourth-instar larva of the mosquito, Culex pipiens pallens after 24 h exposure. Of the tested extracts, the ethanol one exhibited the highest larvicidal activity (LC50 = 22.69 mg/L. Amorphigenin (8'-hydroxyrotenone, a rotenoid compound which exhibits a strong larvicidal activity with LC50 and LC90 values of 4.29 and 11.27 mg/L, respectively, was isolated from the ethanol extract by column chromatograpy. Its structure was elucidated by 1H-NMR, UV and IR spectral data. Furthermore, investigation of amorphigenin’s effects on mitochondrial complex I activity and protein synthesis in C. pipiens pallens larvae reveals that amorphigenin decreases mitochondrial complex I activities to 65.73% at 10.45 μmol/L, compared to the control, when NADH were used as the substrate. Meanwhile, amorphigenin at 10.45 μmol/L also caused a 1.98-fold decrease in protein content, compared to the control larvae treated with acetone only.

  3. Mosquito larvicidal and ovicidal activity of puffer fish extracts against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Samidurai, Kaliyaperumal; Mathew, Nisha

    2013-03-01

    The extracts of liver (LE), ovary (OE), skin (SE) and muscle (ME) tissues of four species of puffer fishes viz., Arothron hispidus, Lagocephalus inermis, Lagocephalus scleratus and Chelonodon patoca were evaluated against larvae and eggs of three mosquito vectors, Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti. The LC50 values were 1194.26, 1382.73 (LE); 1421.42, 1982.73 (OE); 7116.86, 15038.98 (ME) and 10817.8 ppm (SE) for An. stephensi and Cx. quinquefasciatus respectively for A. hispidus. In the case of L. inermis, the LC50 values were 1163.83, 1556.1 and 2426.38 (LE); 1653.53, 2734.74 (OE); 6067.47 (ME) and 10283.04 ppm (SE) for An. stephensi, Cx. quinquefasciatus and Ae. aegypti respectively. The LC50 values were 1509.98, 1608.69 (LE) and 1414.9, 2278.69 ppm (OE) for An. stephensi and Cx. quinquefasciatus respectively for the extracts of L. scleratus. In the case C. patoca extracts the LC50 values were 1182.29, 1543.00, 2441.03 (LE) and 1076.13, 2582.11 ppm (OE) for An. stephensi, Cx. quinquefasciatus and Ae. aegypti respectively. OE and LE of all puffer fishes exhibited zero percent egg hatchability from 600 to 1000 ppm against eggs of An. stephensi and Cx. quinquefasciatus. This study shows that puffer toxins are effective in killing the larvae and eggs of mosquitoes.

  4. The Effect of West Nile Virus Infection on the Midgut Gene Expression of Culex pipiens quinquefasciatus Say (Diptera: Culicidae

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    Chelsea T. Smartt

    2016-12-01

    Full Text Available The interaction of the mosquito and the invading virus is complex and can result in physiological and gene expression alterations in the insect. The association of West Nile virus (WNV and Culex pipiens quinquefasciatus mosquitoes results in measurable changes in gene expression; 22 gene products were shown previously to have altered expression. Sequence analysis of one product, CQ G1A1, revealed 100% amino acid identity to gram negative bacteria binding proteins (CPQGBP in Cx. p. quinquefasciatus, Aedes aegypti (70% and Anopheles gambiae (63% that function in pathogen recognition. CQ G1A1 also was differentially expressed following WNV infection in two populations of Cx. p. quinquefasciatus colonized from Florida with known differences in vector competence for WNV and showed spatial and temporal gene expression differences in midgut, thorax, and carcass tissues. These data suggest gene expression of CQ G1A1 is influenced by WNV infection and the WNV infection-controlled expression differs between populations and tissues.

  5. Blood Meal Identification of the Mosquito (Diptera: Culicidae) Specimens Belong to Culex pipiens Complex that were Collected from Kayseri Province.

    Science.gov (United States)

    Korkmaz, Seval; Yıldırım, Alparslan; Düzlü, Önder; Çiloğlu, Arif; Önder, Zuhal; İnci, Abdullah

    2016-12-01

    This study aimed to determine the host preferences in blood meal of specimens belonging to Culex pipiens complex. A total of 1284 female mosquitos were morphologically examined, and genomic DNA isolations were individually performed on 376 (28.4%) specimens that were determined to be Cx. pipiens complex. PCR was performed with primers to specifically amplify the avian and mammalian mitochondrial cytochrome b (mt-cytb) gene region. Amplicons were cloned, and the obtained plasmids were sequenced to determine host species. Of 376 specimens, 148 (39.4%) were positive for the avian and/or mammalian blood meal. Among the positive specimens, 43, 98, and seven were determined to be positive for only mammalian, avian, and both avian and mammalian blood, respectively. Avian host preference in blood meal of the specimens belonging to Cx. pipiens was found to be significant. Of 15 avian blood positive isolates, nine, three, two, and one were designated as blood meal from avian species in Passeriformes, Accipitriformes, Columbiformes, and Strigiformes orders, respectively. While six, four, three, and two out of 15 mammalian blood-positive specimens were found to be positive for human, cattle, sheep, and dog blood, respectively. Molecular data regarding the host preferences of the Cx. pipiens species complex in blood meal were revealed for the first time in Turkey with this study.

  6. Mosquito larvicidal and ovicidal properties of Pithecellobium dulce (Roxb. Benth. (Fabaceae against Culex quinquefasciatus Say (Diptera: Culicidae

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    Govindarajan Marimuthu

    2014-04-01

    Full Text Available Objective: To assess the larvicidal and ovicidal potential of the crude hexane, benzene, chloroform, ethyl acetate and methanol solvent extracts from the medicinal plant, Pithecellobium dulce (P. dulce against filariasis vector mosquito, Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Twenty five early third instar larvae of Cx. quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO (2005. The larval mortality was observed after 24 h of treatment. The ovicidal activity was determined against Cx. quinquefasciatus mosquito eggs to various concentrations ranging from 100-750 mg/L under the laboratory conditions. Results: The methanol extract of the leaves and seed of P. dulce was the most effective against the larvae with LC 50 and LC90 values 164.12 mg/L, 214.29 mg/L, 289.34 mg/L and 410.18 mg/L being observed after 24 h of exposure. The efficacy of methanol was followed by that of the ethyl acetate, chloroform, benzene and hexane extracts. The mean percent hatchability of the egg rafts were observed after 48 h of treatment. About 100% mortality was observed at 500 mg/L for leaf and 750 mg/L for seed methanol extracts of P. dulce. Conclusions: From the results, it can be concluded that the larvicidal and ovicidal effect of P. dulce against Cx. quinquefasciatus make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.

  7. Mosquito larvicidal properties of Impatiens balsamina (Balsaminaceae against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae

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    Marimuthu Govindarajan

    2014-03-01

    Full Text Available Objective: To assess the larvicidal potential of the crude benzene, chloroform, ethyl acetate and methanol solvent extracts of the medicinal plant Impatiens balsamina against Anopheles stephensi (An. stephensi, Aedes aegypti (Ae. aegypti and Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Twenty five third instar larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol recommended by WHO. The larval mortality was observed after 24 h of treatment. Results: Among extracts tested, the highest larvicidal activity was observed in leaf methanol extract of Impatiens balsamina against An. stephensi, Ae. aegypti and Cx. quinquefasciatus with the LC50 and LC90 values 98.04, 119.68, 125.06 and 172.93, 210.14, 220.60 mg/L, respectively. Conclusions: From the results it can be concluded that the larvicidal effect of Impatiens balsamina against An. stephensi, Ae. aegypti and Cx. quinquefasciatus make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.

  8. Mosquito repellent properties of Delonix elata (L. gamble (Family: Fabaceae against filariasis vector, Culex quinquefasciatus Say. (Diptera: Culicidae

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    Marimuthu Govindarajan

    2014-02-01

    Full Text Available Objective: To determine the repellent activity of hexane, ethyl acetate, benzene, chloroform and methanol extract of Delonix elata (D. elata leaf and seed against Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Evaluation was carried out in a net cage (45 cm伊30 cm伊25 cm containing 100 blood starved female mosquitoes of Cx. quinquefasciatus. Repellent activity was carried out in the laboratory conditions according to the WHO 2009 protocol. Plant crude extracts of D. elata were applied at 1.0, 2.5, and 5.0 mg/cm2 separately in the exposed fore arm of study subjects. Ethanol was used as the sole control. Results: In this study, the applied plant crude extracts were observed to protect against mosquito bites. There were no allergic reactions experienced by the study subjects. The repellent activity of the extract was dependent on the strength of the extract. Among the tested solvents, the leaf and seed methanol extract showed the maximum efficacy. The highest concentration of 5.0 mg/cm2 provided over 150 min and 120 min protection, respectively. Conclusions: Crude extracts of D. elata exhibit the potential for controlling Cx. quinquefasciatus, the mosquito vector of filariasis.

  9. Sampling gravid Culex quinquefasciatus (Diptera: Culicidae) in Tanzania with traps baited with synthetic oviposition pheromone and grass infusions.

    Science.gov (United States)

    Mboera, L E; Takken, W; Mdira, K Y; Pickett, J A

    2000-01-01

    The effectiveness of traps baited with (5R,6S)-6-acetoxy-5-hexadecanolide (the synthetic oviposition pheromone) and grass infusions in sampling a population of gravid Culex quinquefasciatus Say was conducted in Muheza, Northeast Tanzania. A counterflow geometry (CFG) trap baited with pheromone and set outdoors, adjacent to a pit latrine building, collected more gravid Cx. quinquefasciatus than a CDC trap baited with pheromone and operated without light. Inside pit latrine buildings, significantly more gravid Cx. quinquefasciatus were collected in a CFG trap-baited with pheromone or grass infusion than in traps baited with tap water. CFG traps baited with either grass infusion or pheromone and set outdoors, away from known breeding sites, caught significantly more gravid Cx. quinquefasciatus than traps baited with tap water. CFG traps baited with pheromone + grass infusion caught significantly more gravid Cx. quinquefasciatus than CFG traps baited with either grass infusion or pheromone. In both cases, the proportion of gravid mosquitoes increased as traps were moved away from a natural emergence site. More gravid Cx. quinquefasciatus were collected in a pheromone-baited CFG trap than were egg rafts deposited in a jar with pheromone-treated water. It is concluded that CFG traps baited with oviposition attractants can be used effectively to sample gravid Cx. quinquefasciatus.

  10. Larvicidal Activities of Indigenous Bacillus thuringiensis Isolates and Nematode Symbiotic Bacterial Toxins against the Mosquito Vector, Culex pipiens (Diptera: Culicidae

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    Ashraf M Ahmed

    2017-06-01

    Full Text Available Background: The incidence of mosquito-borne diseases and the resistance of mosquitoes to conventional pesticides have recently caused a panic to the authorities in the endemic countries. This study was conducted to identify native larvicidal biopesticides against Culex pipiens for utilization in the battle against mosquito-borne diseases.Methods: Larvicidal activities of new indigenous Bacillus thuringiensis isolates and crude toxin complexes (TCs of two nematode bacterial-symbionts, Photorhabdus luminescens akhurstii (HRM1 and Ph. luminescens akhurstii (HS1 that tested against Cx. pipiens. B. thuringiensis isolates were recovered from different environmental samples in Saudi Arabia, and the entomopathogenic nematodes, Heterorhabditis indica (HRM1 and He. sp (HS1 were iso­lated from Egypt. Larvicidal activities (LC50 and LC95 of the potentially active B. thuringiensis strains or TCs were then evaluated at 24 and 48h post-treatment.Results: Three B. thuringiensis isolates were almost as active as the reference B. thuringiensis israelensis (Bti-H14, and seven isolates were 1.6–5.4 times more toxic than Bti-H14. On the other hand, the TCs of the bacterial sym­bionts, HRM1 and HS1, showed promising larvicidal activities. HS1 showed LC50 of 2.54 folds that of HRM1 at 24h post-treatment. Moreover, histopathological examinations of the HS1-treated larvae showed deformations in midgut epithelial cells at 24h post-treatment.Conclusion: Synergistic activity and molecular characterization of these potentially active biocontrol agents are currently being investigated. These results may lead to the identification of eco-friend mosquito larvicidal product(s that could contribute to the battle against mosquito-borne diseases.

  11. Larvicidal and repellent properties of some essential oils against Culex tritaeniorhynchus Giles and Anopheles subpictus Grassi (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu

    2011-02-01

    To investigate the larvicidal and repellent properties of essential oils from various parts of four plant species Cymbopogan citrates, Cinnamomum zeylanicum, Rosmarinus officinalis and Zingiber officinale against Culex tritaeniorhynchus (Cx. tritaeniorhynchus) and Anopheles subpictus (An. subpictus). Essential oils were obtained by hydro-distillation method. The mosquitoes were reared in the vector control laboratory and twenty five late third instar larvae of Cx. tritaeniorhynchus and An. subpictus were exposed to based on the wide range and narrow range test, essential oil tested at various concentrations ranging from 25 to 250 ppm. The larval mortality was observed after 24 h under the laboratory conditions. The repellent efficacy was determined against two mosquito species at three concentrations viz., 1.0, 2.5 and 5.0 mg/cm(2) under laboratory conditions. Results showed all the four plant essential oil produced significant larval mortality against two mosquito species. However, the highest larvicidal activity was observed in the essential oil from Zingiber officinale against Cx. tritaeniorhynchus and An. subpictus with the LC(50) and LC(90) values as 98.83, 57.98 ppm and 186.55, 104.23 ppm, respectively. All the four essential oil shows significant repellency against Cx. tritaeniorhynchus than An. subpictus. Among four essential oil tested the highest repellency was observed in Zingiber officinale, a higher concentration of 5.0 mg/cm(2) provided 100% protection up to 150 and 180 min against Cx. tritaeniorhynchus and An. subpictus, respectively. In this work, it can be concluded that four essential oils which were distilled from Cymbopogan citrates, Cinnamomum zeylanicum, Rosmarinus officinalis and Zingiber officinale showed promising larvicidal and repellent agent against Cx. tritaeniorhynchus and An. subpictus. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  12. Permethrin resistance variation and susceptible reference line isolation in a field population of the mosquito, Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Yang, Ting; Liu, Nannan

    2014-10-01

    This study examines the genetic variations and mechanisms involved in the development of permethrin resistance in individual mosquitoes from a field population of Culex quinquefasciatus, HAmCq(G0) , and characterizes susceptible reference lines of mosquitoes with a similar genetic background to the field HAmCq(G0) strain. Six upregulated cytochrome P450 genes, CYP9M10, CYP9J34, CYP6P14, CYP9J40, CYP6AA7, and CYP4C52v1, previously identified as being upregulated in the larvae of resistant HAmCq(G8) mosquitoes were examined in the larvae of 3 strains (susceptible S-Lab, parental HAmCq(G0) and permethrin-selected highly resistant HAmCq(G8) ) and 8 HAmCq(G0) single-egg raft colonies, covering a range of levels of susceptibility/resistance to permethrin and exhibiting different variations in the expression of A and/or T alleles at the L-to-F kdr locus of the sodium channel. The 2 lines with the lowest tolerance to permethrin and bearing solely the susceptible A allele at the L-to-F kdr locus of the sodium channels, from colonies Cx_SERC5 and Cx_SERC8, showed lower or similar levels of all 6 of the P450 genes tested compared with the S-Lab strain, suggesting that these 2 lines could be used as the reference mosquitoes in future studies characterizing insecticide resistance in HAmCq mosquitoes. This study also provides a detailed investigation of the mechanisms involved in insecticide resistance in individuals within a population: individuals with elevated levels of resistance to permethrin all displayed one or more potential resistance mechanisms-either elevated levels of P450 gene expression, or L-to-F mutations in the sodium channel, or both. © 2013 Institute of Zoology, Chinese Academy of Sciences.

  13. Expression Profiles and RNAi Silencing of Inhibitor of Apoptosis Transcripts in Aedes, Anopheles, and Culex Mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Puglise, Jason M; Estep, Alden S; Becnel, James J

    2016-03-01

    Effective mosquito control is vital to curtail the devastating health effects of many vectored diseases. RNA interference (RNAi)-mediated control of mosquitoes is an attractive alternative to conventional chemical pesticides. Previous studies have suggested that transcripts for inhibitors of apoptosis (IAPs) may be good RNAi targets. To revisit and extend previous reports, we examined the expression of Aedes aegypti (L.) IAPs (AaeIAPs) 1, 2, 5, 6, 9, and a viral IAP-associated factor (vIAF) as well as Anopheles quadrimaculatus Say and Culex quinquefasciatus Say IAP1 homologs (AquIAP1 and CquIAP1) in adult females. Expression profiles of IAPs suggested that some older female mosquitoes had significantly higher IAP mRNA levels when compared to the youngest ones. Minor differences in expression of AaeIAPs were observed in mosquitoes that imbibed a bloodmeal, but the majority of the time points (up to 48 h) were not significantly different. Although in vitro experiments with the Ae. aegypti Aag-2 cell line demonstrated that the various AaeIAPs could be effectively knocked down within one day after dsRNA treatment, only Aag-2 cells treated with dsIAP1 displayed apoptotic morphology. Gene silencing and mortality were also evaluated after topical application and microinjection of the same dsRNAs into female Ae. aegypti. In contrast to previous reports, topical administration of dsRNA against AaeIAP1 did not yield a significant reduction in gene expression or increased mortality. Knockdown of IAP1 and other IAPs by microinjection did not result in significant mortality. In toto, our findings suggest that IAPs may not be suitable RNAi targets for controlling adult mosquito populations.

  14. Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus) in four strains of Culex tarsalis (Diptera: Culicidae): an immunocytochemical study.

    Science.gov (United States)

    Oviedo, Marco V Neira; Romoser, William S; James, Calvin Bl; Mahmood, Farida; Reisen, William K

    2011-04-18

    BACKGROUND: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV), we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion. METHODS: Using immunostained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains - Coachella Valley, Riverside County (COAV) and Kern National Wildlife Refuge (KNWR); and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP), and WEEV resistance (WR). RESULTS AND CONCLUSIONS: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth, whereas the WR and KNWR strains were less competent. Consistent with earlier studies, WEEV resistance appeared to be related to a dose-dependent midgut infection barrier, and a midgut escape barrier. The midgut escape barrier was not dependent upon the ingested viral dose. Consistent with midgut infection modulation, disseminated infections were less common in the WR and KNWR

  15. Larvicidal efficacy of various formulations of Bacillus sphaericus against the resistant strain of Culex quinquefasciatus (Diptera: Culicidae) from southern India.

    Science.gov (United States)

    Subbiah, P; Ramesh, N; Sundaravadivelu, K; Samuel, P; Tyagi, B K

    2009-04-01

    Use of Bacillus sphaericus Neide (Bs) as potential biolarvicide in developing countries is limited due to development of resistance by target mosquitoes. Efforts are taken to look for appropriate formulations or combination of Bs to prevent or delay resistance problem. Here, we report the efficacy of a formulated Bs product to kill Bs resistant Culex quinquefasciatus Say larvae. The laboratory reared resistance colony was maintained by subjecting selection pressure with Bs (2362) toxin. Bioassays were conducted with lyophilized, standard formulated and Bs formulated by us (all belong to strain 2362, serotype H5a5b) against Bs resistant and susceptible colonies. The Bs resistant larvae showed a high level of resistance against lyophilized toxin with resistance ratio (RR) of 8375.2, 1055.6 and 11422.3 folds at LC(50), LC(90) and LC(95) levels, respectively, when compared with Bs susceptible larvae. With formulation of standard powder, the RR between Bs resistant and susceptible larvae were 1.01, 1.13 and 1.19 folds only at LC(50), LC(90) and LC(95) levels, respectively. This observation was comparable with our formulation prepared by a ground mixture of lyophilized Bs and a placebo (plaster of Paris). It is evident from our study, that the placebo present in our Bs 2362 formulation was responsible for increasing the efficacy of Bs lyophilized toxin against resistant larvae. The putative mechanism behind this toxicity phenomenon remains to be investigated to evolve new mosquito control strategies. A cross resistance to indigenous strain of Bs B42 (H5a5b) against Bs resistant larvae was also reported in this study.

  16. Evaluation of water and ethanol extracts of Schinus molle Linn. against immature Culex quinquefasciatus Say (Diptera: Culicidae

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    Kidanemariam Girmay

    2014-06-01

    Full Text Available Objective: To evaluate larvicidal and pupicidal activities of aqueous and ethanol extract of different parts of Schinus molle against filarial vector, Culex quinquefasciatus (Cx. quinquefasciatus in the laboratory. Methods: The mortality rate of third, fourth instar larvae and pupal stages were tested at 20, 40, 60, 80 and 100 mg/L of plant extract using WHO standard protocol with modifications. The mortality rate was recorded continuously for 24, 48 and 72 h post exposure period and percentage mortality was calculated. Results: Maximum percentage mortality of third instar was 83.3% in ethanol extract of mature fruit at 100 mg/L after 24 h exposure period. After 48 h exposure period, 93.3% percentage mortality was recorded in ethanol extract of immature fruit at 100 mg/L. After 72 h exposure period, 100% mortality was recorded in water extract of leaf at 100 mg/L. In fourth instar larvae, maximum percentage mortality of 63.3% was recorded in water extract of mature fruit and ethanol extract of immature and mature fruit at 100 mg/L after 24 h exposure period. After 48 h exposure period 86.6% mortality was recorded in ethanol extract of mature fruit at 100 mg/L. After 72 h exposure period, 93.3% mortality was recorded in ethanol extract of mature fruit at 100 mg/L. In general immature Cx. quinquefasciatus, percentage mortality was increased with increase in exposure time and concentration of the plant extracts tested. Conclusions: From this laboratory study, Schinus molle plant parts were proved to have larvicidal and pupicidal activity against immature Cx. quinquefasciatus.

  17. Distribuição sazonal de Culex (Culex eduardoi Casal & Garcia (Diptera, Culicidae em criadouros antrópicos introduzidos em mata residual degradada, área urbana de Curitiba, Paraná,Brasil Seazonal distribution of Culex (Culex eduardoi Casal & Garcia (Diptera, Culicidae in artificial receptacles in disturbed patch of forest degraded inurban area of Curitiba, Paraná, Brazil

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    Magda Clara Vieira da Costa Ribeiro

    2002-07-01

    Full Text Available The utilization of artificial receptacles to oviposition by mosquitoes in forest environment may indicate a sinantropic tendency or behaviour. Our data revealed that tires were as the most acceptable breeding for Culex (Culex eduardoi Casal & Garcia 1968.The population density of this species was higher and summer seasons.

  18. Larvicidal efficacy of Sphaeranthus indicus, Cleistanthus collinus and Murraya koenigii leaf extracts against filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Kovendan, Kalimuthu; Arivoli, Subramaniam; Maheshwaran, Rajan; Baskar, Kathirvelu; Vincent, Savariar

    2012-09-01

    Sphaeranthus indicus, Cleistanthus collinus and Murraya koenigii leaf extracts were tested against the third instar larvae of Culex quinquefasciatus. The plant material was shade dried at room temperature and powdered coarsely. From each plant, 500 g powder was macerated with 1.5 L of hexane, chloroform and ethyl acetate sequentially for a period of 72 h each and filtered. The yield of the S. indicus, C. collinus and M. koenigii crude extracts by hexane, chloroform and ethyl acetate was 9.16, 11.71 and 10.83 g for S. indicus; 8.17, 10.69 and 9.85 g for C. collinus; and 10.11, 11.92 and 9.87 g for M. koenigii, respectively. The extracts were concentrated at reduced temperature on a rotary vacuum evaporator and stored at a temperature of 4°C. The S. indicus, C. collinus and M. koenigii leaf extracts at 250, 500, 750 and 1,000 ppm caused a significant mortality of C. quinquefasciatus. The LC(50) and LC(90) values of S. indicus, C. collinus and M. koenigii against third instar larvae at 24, 48 and 72 h (hexane, chloroform and ethyl acetate) were the following: S. indicus LC(50) values were 544.93, 377.86 and 274.79 ppm and LC(90) values were 1,325.32, 1,572.55 and 1,081.29 ppm at 24 h; C. collinus LC(50) values were 375.34, 318.29 and 226.10 ppm and LC(90) values were 699.65, 1,577.62 and 1,024.92 ppm at 24 h; and M. koenigii LC(50) values were 963.53, 924.85 and 857.62 ppm and LC(90) values were 1,665.12, 1,624.68 and 1,564.37 ppm at 24 h, respectively. However, the highest larval mortality was observed in C. collinus followed by S. indicus and M. koenigii of various concentrations at 24, 48 and 72 h. The study proved that S. indicus, C. collinus and M. koenigii leaf extracts had larvicidal property against species of C. quinquefasciatus. This is an ideal ecofriendly approach for the control of vector control programmes.

  19. Asymmetric effects of native and exotic invasive shrubs on ecology of the West Nile virus vector Culex pipiens (Diptera: Culicidae).

    Science.gov (United States)

    Gardner, Allison M; Allan, Brian F; Frisbie, Lauren A; Muturi, Ephantus J

    2015-06-16

    Exotic invasive plants alter the structure and function of native ecosystems and may influence the distribution and abundance of arthropod disease vectors by modifying habitat quality. This study investigated how invasive plants alter the ecology of Culex pipiens, an important vector of West Nile virus (WNV) in northeastern and midwestern regions of the United States. Field and laboratory experiments were conducted to test the hypothesis that three native leaf species (Rubus allegheniensis, blackberry; Sambucus canadensis, elderberry; and Amelanchier laevis, serviceberry), and three exotic invasive leaf species (Lonicera maackii, Amur honeysuckle; Elaeagnus umbellata, autumn olive; and Rosa multiflora, multiflora rose) alter Cx. pipiens oviposition site selection, emergence rates, development time, and adult body size. The relative abundance of seven bacterial phyla in infusions of the six leaf species also was determined using quantitative real-time polymerase chain reaction to test the hypothesis that variation in emergence, development, and oviposition site selection is correlated to differences in the diversity and abundance of bacteria associated with different leaf species, important determinants of nutrient quality and availability for mosquito larvae. Leaf detritus from invasive honeysuckle and autumn olive yielded significantly higher adult emergence rates compared to detritus from the remaining leaf species and honeysuckle alleviated the negative effects of intraspecific competition on adult emergence. Conversely, leaves of native blackberry acted as an ecological trap, generating high oviposition but low emergence rates. Variation in bacterial flora associated with different leaf species may explain this asymmetrical production of mosquitoes: emergence rates and oviposition rates were positively correlated to bacterial abundance and diversity, respectively. We conclude that the displacement of native understory plant species by certain invasive shrubs

  20. Culicidae (Diptera, Culicomorpha from the western Brazilian Amazon: Juami-Japurá Ecological Station

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    Rosa Sá Gomes Hutchings

    2010-01-01

    Full Text Available With 312 trap-hours of sampling effort, 1554 specimens of Culicidae (Diptera were collected, using CDC and Malaise traps, in nine different locations along the Juami River, within the Juami-Japurá Ecological Station, Amazonas State, Brazil. A list of mosquito species with 54 taxa is presented, which includes three new distributional records for the state of Amazonas. The species found belong to the genera Anopheles, Aedeomyia, Aedes, Psorophora, Culex, Coquillettidia, Sabethes, Wyeomyia and Uranotaenia.

  1. [Mosquitoes (Diptera, Culicidae) of Smir marshes (northwest of Morocco): inventory and biotypology].

    Science.gov (United States)

    El Joubari, M; Louah, A; Himmi, O

    2014-02-01

    The Smir marshes are a favorable environment for the growth of many mosquitoes (Diptera, Culicidae). The inventory of Culicidae species reveals 14 species, is 33% of the species of Morocco, distributed in four genera: Culex, Culiseta, Ochlerotatus and Anopheles (with 5, 2, 5 and 2 species respectively) which Anopheles labranchiae, vector of the agent of the malaria in Morocco until 2004. In this study, we investigated the spatiotemporal mesological affinities and we tried to explain the biotypology of mosquito populations of the site. These analyzes revealed several groups of stations and species according to various parameters, especially salinity.

  2. Registros de mayor altitud para mosquitos (Diptera: Culicidae en Venezuela

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    Juan-Carlos Navarro

    2010-03-01

    Full Text Available Los mosquitos (Diptera: Culicidae son insectos holometábolos con estadios inmaduros acuáticos que utilizan una amplia variedad de hábitats larvales, desde cuerpos de agua en el suelo hasta Fitotelmata (depósitos de agua en las plantas y depósitos artificiales. La disponibilidad de sitios de reproducción a menudo determina el límite superior del ámbito de los mosquitos. Nosotros construimos una base de datos de 9 607 registros, 432 localidades, 19 géneros y 254 especies. La coordillera Andina posee el 77% de los registros con mayor altitud incluyendo Aedes euris con un registro a 3 300 m, seguido por tres especies de Anopheles -subgénero Kerteszia- con una altitud máxima de 2 680 m. Wyeomyia bicornis y Culex daumastocampa a 2 550 m fueron los registros de mayor altitud en la cordillera Costera- Central, mientras que el record más alto en Pantepui fue Wyeomyia zinzala a 2 252 m. El 60% de los registros de máxima altitud están representados por especies asociadas con fitotelmata (Bromeliaceae y Sarraceniaceae. Los límites superiores de Culex quinquefasciatus y Anopheles (Kerteszia podría representar el límite teórico para la transmisión de filariasis o arbovirus, por Culex y malaria por Anopheles (Kerteszia en Venezuela. Del mismo modo, un vector del dengue, Aedes aegypti, no ha sido registrado por encima de 2 000 m.Highest mosquito records (Diptera: Culicidae in Venezuela. Mosquitoes (Diptera: Culicidae are holometabolous insects with aquatic immature stages, which use a broad variety of larval habitats, from ground water bodies to Phytothelmata (water deposits in plants and artificial deposits. The availability of breeding sites often determines the upper limits of mosquito ranges. We built a database with 9 607 records with 432 localities, 19 genera and 254 species. The Andean mountains have 77% of the highest mosquito records including Aedes euris with record at 3 133 m, followed by three species of Anopheles -subgenera

  3. Larvicidal, Biological and Genotoxic Effects, and Temperature-Toxicity Relationship of Some Leaf Extracts of Nerium oleander (Apocynaceae) on Culex pipiens (Diptera: Culicidae)

    National Research Council Canada - National Science Library

    El-Sayed, Shaurub H; El-Bassiony, Ghada M

    2016-01-01

    The present study was undertaken to study the larvicidal activity of different extracts of Nerium oleander leaves, and post-treatment temperature- toxicity relationship of these extracts against Culex pipiens...

  4. The Mosquitoes of the Subgenus Culex in Southwestern Asia and Egypt (Diptera: Culicidae) (Contributions of the American Entomological Institute. Volume 24, Number 1, 1988)

    Science.gov (United States)

    1988-01-01

    data: “Type // Entebbe / Dr. Row // Culex / quasigelidus / (Type) Theobald // Entebbe. / bred from / larvae. / Sep . 20. 02”; left wing mounted on...Bigot, J.M.F. 1857. Dipteros, pp. 328-349. In: R. de la Sagra, Historia fisica, politica y natural de la lsla de Cuba. Vol. 7. Paris. 1859. Dipteres de...Naturaleza Mexico 7: 203-213. Harbach: Subgenus Culex in Southwestern Asia 135 Say, T. 1823. Descriptions of dipterous insects of the United States

  5. Genetic Characterization of Spondweni and Zika Viruses and Susceptibility of Geographically Distinct Strains of Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus (Diptera: Culicidae) to Spondweni Virus

    Science.gov (United States)

    2016-10-26

    albopictus [19,22], and Culex quinquefasciatus (C. F. Junqueira 105 Ayres pers. comm.). 106 107 108 Methods 109 110 Virus strains and virus...has been discussed as a potential vector in Brazil (C. F. 237 Junqueira Ayres pers. comm.). Early work demonstrated that Ae. aegypti was a 238

  6. Larvicidal, Biological and Genotoxic Effects, and Temperature-Toxicity Relationship of Some Leaf Extracts of Nerium oleander (Apocynaceae) on Culex pipiens (Diptera: Culicidae)

    OpenAIRE

    El-Sayed, Shaurub H; El-Bassiony, Ghada M

    2015-01-01

     Background: The present study was undertaken to study the larvicidal activity of different extracts of Nerium ole­ander leaves, and post-treatment temperature- toxicity relationship of these extracts against Culex pipiens. Further, the most potent extract was used to evaluate its biological and genotoxic activities. Methods: Crude extracts of N. oleander leaves were prepared using water, chloroform, acetone and diethyl ether as solvents. Extraction was carried out using soxhlet apparatus. Bi...

  7. Evaluation of Multi Potential Bioactive Endod, Phytolacca dodecandra (L’ Herit) Berries Extracts Against Immature Filarial Vector Culex quinquefasciatus Say (Diptera: Culicidae)

    OpenAIRE

    Nagappan Raja; Tigab Temesgen; Mamaye Tesera; Muche Tadele; Shiferaw Moges; Nurie Misganaw

    2012-01-01

    Aim of the present study was to evaluate larvicidal and pupicidal properties of Phytolacca dodecandra plant extracts against immature filarial vector, Culex quinquefasciatus. The powdered berries were extracted with petroleum ether, acetone, benzene, methanol and water. The crude residue obtained from the extraction was used to prepare 62.5, 125, 250, 500 and 1000 ppm concentration, respectively. The experiment was conducted by using standard WHO protocol with modifications. The immature mosq...

  8. A New Species of Culex (Eumelanomyia) from India with Descriptions of Pupae and Larvae of Cx. pluvialis Barraud and Cx. iphis Barraud (Diptera: Culicidae)

    Science.gov (United States)

    1977-01-01

    crown composed of 4,5 flat and blunt spicules laterally and several dark, spinelike spicules mesally; basal sternal process absent; cereal setae 3,4...filament well developed. DISTRIBUTION. In addition to the previous records from India and Peninsu- lar Malaysia (Sirivanakarn 1972; Sirivanakarn and...Ramalingam. 1976. A new species of CuZex (EwneZunoymial Theobald with notes on three other species from Malaysia (Diptera: Culici- dae). Mosq

  9. Vector competence of Culex restuans (Diptera: Culicidae) from two regions of Chicago with low and high prevalence of West Nile virus human infections.

    Science.gov (United States)

    Mutebi, J P; Swope, B N; Doyle, M S; Biggerstaff, B J

    2012-05-01

    Vector competence studies for West Nile virus (WNV) were conducted for two Culex (Culex) restuans Theobald populations Edison Park (EP) and Illinois Medical District (IMD), in Chicago, IL. The aim was to determine if there were differences between mosquito populations that contributed to the observed differences in the prevalence of WNV. Percentages of orally infected, disseminated, and transmitting mosquitoes were estimated using a generalized linear mixed effects model including a random effect for family to account for anticipated within-family correlation. Analysis indicated that percentages of infected, disseminated, and transmitting mosquitoes were not significantly different between EP and IMD. The within-family correlation was 0.46 (95% CI 0.28, 0.67), indicating reasonably strong tendency for WNV titers of bodies, saliva, and legs within families to be similar. Overall, our results show that vector competence of Cx. restuans for WNV is not a contributing factor to the observed differences in WNV human cases between the EP and IMD areas of Chicago.

  10. Various Levels of Cross-Resistance to Bacillus sphaericus Strains in Culex pipiens (Diptera: Culicidae) Colonies Resistant to B. sphaericus Strain 2362

    Science.gov (United States)

    Nielsen-LeRoux, Christina; Rao, D. Raghunatha; Murphy, Jittawadee Rodcharoen; Carron, Alexandre; Mani, T. R.; Hamon, Sylviane; Mulla, Mir S.

    2001-01-01

    We studied the cross-resistance to three highly toxic Bacillus sphaericus strains, IAB-59 (serotype H6), IAB-881 (serotype H3), and IAB-872 (serotype H48), of four colonies of the Culex pipiens complex resistant to B. sphaericus 2362 and 1593, both of which are serotype H5a5b strains. Two field-selected highly resistant colonies originating from India (KOCHI, 17,000-fold resistance) and France (SPHAE, 23,000-fold resistance) and a highly resistant laboratory-selected colony from California (GeoR, 36,000-fold resistance) showed strong cross-resistance to strains IAB-881 and IAB-872 but significantly weaker cross-resistance to IAB-59 (3- to 43-fold resistance). In contrast, a laboratory-selected California colony with low-level resistance (JRMM-R, 5-fold resistance) displayed similar levels of resistance (5- to 10-fold) to all of the B. sphaericus strains tested. Thus, among the mosquitocidal strains of B. sphaericus we identified a strain, IAB-59, which was toxic to several Culex colonies that were highly resistant to commercial strains 2362 and 1593. Our analysis also indicated that strain IAB-59 may possess other larvicidal factors. These results could have important implications for the development of resistance management strategies for area-wide mosquito control programs based on the use of B. sphaericus preparations. PMID:11679325

  11. Cubiertas de auto abandonadas como sitios de cría de Culex eduardoi (Diptera: Culicidae en el Parque Provincial Pereyra Iraola, Provincia de Buenos Aires

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    Alejandra RUBIO

    2011-01-01

    Full Text Available El conocimiento sobre la fauna de mosquitos que se cría en cubiertas de auto es realmente escaso en Argentina. El objetivo de este estudio fue caracterizar una población de inmaduros de Culex eduardoi Casal & Garcia en una acumulación de cubiertas abandonadas en un bosque suburbano de la Provincia de Buenos Aires. Entre noviembre 2009 y mayo 2010, se recolectaron mensualmente larvas de mosquitos en 27 cubiertas de auto abandonadas en un sector boscoso del Parque Provincial Pereyra Iraola. Se recolectaron en total 1.009 larvas del tercer y cuarto estadio de Cx. eduardoi, y el índice de contenedores (IC global fue 66,3% (106/160. Culex eduardoi estuvo presente durante todos los meses, aunque el IC difirió significativamente (χ2(6 = 15,11; p < 0,05, alcanzando valores máximos en noviembre y diciembre (76 y 92,5% respectivamente. En primavera, la abundancia relativa de larvas también fue máxima y el número medio de las recolectadas por criadero fue de 9,5 (mín. 3,5 en marzo; máx.15,1 en noviembre. Otras especies halladas en los contenedores estudiados fueron Cx. pipiens L. y Toxorhynchites theobaldi Dyar & Knab. Los presentes hallazgos aportan nuevos conocimientos sobre los culícidos de cubiertas en Argentina.

  12. Studies on the impact of biosynthesized silver nanoparticles (AgNPs) in relation to malaria and filariasis vector control against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Subarani, Selladurai; Sabhanayakam, Selvi; Kamaraj, Chinnaperumal

    2013-02-01

    Biosynthesized nanoparticles have been achieved using environmentally acceptable plant extract and eco-friendly reducing and capping agents. The present study was based on assessments of the larvicidal activities to determine the efficacies of synthesized silver nanoparticles (AgNPs) using aqueous leaf extract of Vinca rosea (L.) (Apocynaceae) against the larvae of malaria vector Anopheles stephensi Liston and filariasis vector Culex quinquefasciatus Say (Diptera: Culicidae). Larvae were exposed to varying concentrations of aqueous extract of V. rosea and synthesized AgNPs for 24, 48, and 72 h. AgNPs were rapidly synthesized using the leaf extract of V. rosea, and the formation of nanoparticles was observed within 15 min. The results recorded from UV-Vis spectrum, Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) support the biosynthesis and characterization of AgNPs. The formation of the AgNPs synthesized from the XRD spectrum compared with the Bragg reflections at 2θ = 29.36, 38.26, 44.51, 63.54, and 77.13° which can be indexed to the (121), (111), (200), (220), and (311) orientations, respectively, confirmed the presence of AgNPs. The FTIR spectra of AgNPs exhibited prominent peaks at the spectra showed sharp and strong absorption band at 3,406.71 to 3,431.90 cm(-1) double in case of NH(2) group of a primary amine (N-H stretch). The presence of the sharp peak at 2,926.54 to 2,925.80 cm(-1) very broad often looks like distorted baseline (O-H carboxylic acids). The band 1,633.26 to 1,625.81 cm(-1) was assigned to C = C alkenes, aromatic ring stretching vibration, respectively. SEM analysis of the synthesized AgNPs clearly showed the clustered and irregular shapes, mostly aggregated and having the size of 120 nm. TEM reveals spherical shape of synthesized AgNPs. Particle size analysis revealed that the size of particles ranges from 25 to 47 nm with average size of 34.61 nm

  13. Larvicidal activity of Wrightia tinctoria R. BR. (Apocynaceae fruit and leaf extracts against the filarial vector Culex quinquefasciatus Say (Diptera: Culicidae

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    Murugesan Sakthivadivel

    2014-02-01

    Full Text Available Objective: To determine the larvicidal activity of crude aqueous and petroleum ether extracts of Wrightia tinctoria fruits and leaves against the filarial vector, Culex quinquefasciatus. Methods: The larvicidal activity was evaluated at concentrations of 0.06%, 0.12%, 0.25%, 0.50% and 1.00%. Larval mortality was observed for 24 and 48 h. Results: Among the plant parts tested, aqueous fruit extract exhibited highest larvicidal activity followed by aqueous leaf extract with LC50 values of 0.17% and 0.09%; 0.21% and 0.11% after 24 and 48 h respectively. Conclusions: Further investigations are needed to elucidate this activity against a wide range of all stages of mosquito species and also the active ingredient(s of the extract responsible for larvicidal activity should be identified.

  14. Larvicidal activity of the methanol extract and fractions of the green fruits of Solanum lycocarpum (Solanaceae against the vector Culex quinquefasciatus (Diptera: Culicidae

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    Thamer Matias Pereira

    2014-10-01

    Full Text Available Introduction The larvicidal activity of Solanum lycocarpum against Culex quinquefasciatus is unknown. Methods We evaluated the larvicidal activity of extracts of the green fruits of Solanum lycocarpum against third and fourth instar larvae of C. quinquefasciatus. Results Dichloromethane and ethyl acetate fractions showed the greatest larvicidal effect at 200mg/L (83.3% and 86.7%, respectively. The methanol and dichloromethane, ethyl acetate, and hydromethanolic fractions demonstrated larvicidal effects against C. quinquefasciatus, with LC50 values of 126.24, 75.13, 83.15, and 207.05mg/L, respectively. Conclusions Thus, when considering new drugs with larvicidal activity from natural products, S. lycocarpum fruits may be good candidate sources.

  15. Ecologia de mosquitos (Diptera, Culicidae em criadouros naturais e artificiais de área rural do norte do Paraná, Brasil: VIII. Influência das larvas predadoras (Toxorhynchites sp., Limatus durhamiie Culex bigoti sobre a população de larvas de Culex Quinquefasciatus e Culex eduardoi Ecology of mosquitoes (Diptera, Culicidae in natural and artificial rural breeding sites in northern Paraná State, Brazil: VIII. The influence of predator larvae (Toxorhynchites sp., Limatus durhamii and Culex bigoti on the populations of Culex quinquefasciatus and Culex eduardoi

    Directory of Open Access Journals (Sweden)

    José Lopes

    1999-01-01

    Full Text Available Larvae of Culex eduardoi, Culex bigoti, Limatus durhamii and Toxorhynchites were collected in a tyre that had been placed in a wood by a river bank. These larvae were present coexisting and in an individualized form. It was observed that Toxorhynchites, Culex bigoti and Limatus durhamii were efficient in reducing the other two species's population. Culex bigoti and Toxorhynchites showed preference for Culex quinquefasciatus larvae, while Limatus durhamii preferred Culex eduardoi. The most efficient predator was Toxorhynchites, and the least efficient was Limatus durhamii. The reduction of the preys' population density was statistically meaningful in the face of the three species considered as predators.

  16. Chemical composition and larvicidal activity of essential oil from Ocimum basilicum (L.) against Culex tritaeniorhynchus, Aedes albopictus and Anopheles subpictus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, M; Sivakumar, R; Rajeswary, M; Yogalakshmi, K

    2013-05-01

    The toxicity of mosquito larvicidal activity of leaf essential oil and their major chemical constituents from Ocimum basilicum were evaluated against Culex tritaeniorhynchus, Aedes albopictus and Anopheles subpictus. The chemical composition of the leaf essential oil was analyzed using gas chromatography-mass spectroscopy. GC-MS revealed that the essential oil of O. basilicum contained 20 compounds. The major chemical components identified were linalool (52.42%), methyl eugenol (18.74%) and 1, 8-cineol (5.61%). The essential oil had a significant toxic effect against late third-stage larvae of Cx. tritaeniorhynchus, Ae. albopictus and An. subpictus with an LC(50) values of 14.01, 11.97 and 9.75 ppm and an LC(90) values of 23.44, 21.17 and 18.56 ppm, respectively. The results could be useful in search for newer, safer, and more effective natural larvicidal agents against Cx. tritaeniorhynchus, Ae. albopictus and An. subpictus. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Characterisation of Culex quinquefasciatus (Diptera: Culicidae larval habitats at ground level and temporal fluctuations of larval abundance in Córdoba, Argentina

    Directory of Open Access Journals (Sweden)

    Marta Grech

    2013-09-01

    Full Text Available The aims of this study were to characterise the ground-level larval habitats of the mosquito Culex quinquefasciatus, to determine the relationships between habitat characteristics and larval abundance and to examine seasonal larval-stage variations in Córdoba city. Every two weeks for two years, 15 larval habitats (natural and artificial water bodies, including shallow wells, drains, retention ponds, canals and ditches were visited and sampled for larval mosquitoes. Data regarding the water depth, temperature and pH, permanence, the presence of aquatic vegetation and the density of collected mosquito larvae were recorded. Data on the average air temperatures and accumulated precipitation during the 15 days prior to each sampling date were also obtained. Cx. quinquefasciatus larvae were collected throughout the study period and were generally most abundant in the summer season. Generalised linear mixed models indicated the average air temperature and presence of dicotyledonous aquatic vegetation as variables that served as important predictors of larval densities. Additionally, permanent breeding sites supported high larval densities. In Córdoba city and possibly in other highly populated cities at the same latitude with the same environmental conditions, control programs should focus on permanent larval habitats with aquatic vegetation during the early spring, when the Cx. quinquefasciatus population begins to increase.

  18. Genetic Characterization of Spondweni and Zika Viruses and Susceptibility of Geographically Distinct Strains of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus (Diptera: Culicidae to Spondweni Virus.

    Directory of Open Access Journals (Sweden)

    Andrew D Haddow

    2016-10-01

    Full Text Available Zika virus (ZIKV has extended its known geographic distribution to the New World and is now responsible for severe clinical complications in a subset of patients. While substantial genetic and vector susceptibility data exist for ZIKV, less is known for the closest related flavivirus, Spondweni virus (SPONV. Both ZIKV and SPONV have been known to circulate in Africa since the mid-1900s, but neither has been genetically characterized by gene and compared in parallel. Furthermore, the susceptibility of peridomestic mosquito species incriminated or suspected in the transmission of ZIKV to SPONV was unknown.In this study, two geographically distinct strains of SPONV were genetically characterized and compared to nine genetically and geographically distinct ZIKV strains. Additionally, the susceptibility of both SPONV strains was determined in three mosquito species. The open reading frame (ORF of the SPONV 1952 Nigerian Chuku strain, exhibited a nucleotide and amino acid identity of 97.8% and 99.2%, respectively, when compared to the SPONV 1954 prototype South African SA Ar 94 strain. The ORF of the SPONV Chuku strain exhibited a nucleotide and amino acid identity that ranged from 68.3% to 69.0% and 74.6% to 75.0%, respectively, when compared to nine geographically and genetically distinct strains of ZIKV. The ORF of the nine African and Asian lineage ZIKV strains exhibited limited nucleotide divergence. Aedes aegypti, Ae. albopictus and Culex quinquefasciatus susceptibility and dissemination was low or non-existent following artificial infectious blood feeding of moderate doses of both SPONV strains.SPONV and ZIKV nucleotide and amino acid divergence coupled with differences in geographic distribution, ecology and vector species support previous reports that these viruses are separate species. Furthermore, the low degree of SPONV infection or dissemination in Ae. albopictus, Ae. aegypti and Cx. quinquefasciatus following exposure to two

  19. Larvicidal, Biological and Genotoxic Effects, and Temperature-Toxicity Relationship of Some Leaf Extracts of Nerium oleander (Apocynaceae on Culex pipiens (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Shaurub H El-Sayed

    2015-10-01

    Full Text Available  Background: The present study was undertaken to study the larvicidal activity of different extracts of Nerium ole­ander leaves, and post-treatment temperature- toxicity relationship of these extracts against Culex pipiens. Further, the most potent extract was used to evaluate its biological and genotoxic activities. Methods: Crude extracts of N. oleander leaves were prepared using water, chloroform, acetone and diethyl ether as solvents. Extraction was carried out using soxhlet apparatus. Bioassay test was carried out on the larvae, and the LC50 of each extract was determined. Thus, newly hatched first instar larvae were treated, and the mortality count was recorded daily till pupation (accumulated mortality. The LC50 of diethyl ether extract, as the most potent ex­tract, was used for the further biological and genotoxic studies. Results: The results obtained indicated that diethyl ether extract of N. oleander leaves was the most potent extract, with LC50 of 10500 mg/l. The toxicity of the four extracts, using the LC50, at 10 °C was higher than that at 35 °C. The LC50 of diethyl ether extract significantly decreased the larval duration, pupal duration, percentage of pupation, percentage of adult emergence, longevity of females, fecundity, and oviposition activity index, whereas the growth index and the percentage of development per day of larvae and pupae were significantly increased compared to non-treated insects. Moreover, treatment with this extract induced significant dominant lethality in both male and female adults.  Conclusion: It appears that diethyl ether extract of N. oleander leaves is potential control agent to Cx. pipiens. 

  20. Larvicidal, Biological and Genotoxic Effects, and Temperature-Toxicity Relationship of Some Leaf Extracts of Nerium oleander (Apocynaceae) on Culex pipiens (Diptera: Culicidae).

    Science.gov (United States)

    El-Sayed, Shaurub H; El-Bassiony, Ghada M

    2016-03-01

    The present study was undertaken to study the larvicidal activity of different extracts of Nerium oleander leaves, and post-treatment temperature- toxicity relationship of these extracts against Culex pipiens. Further, the most potent extract was used to evaluate its biological and genotoxic activities. Crude extracts of N. oleander leaves were prepared using water, chloroform, acetone and diethyl ether as solvents. Extraction was carried out using soxhlet apparatus. Bioassay test was carried out on the larvae, and the LC50 of each extract was determined. Thus, newly hatched first instar larvae were treated, and the mortality count was recorded daily till pupation (accumulated mortality). The LC50 of diethyl ether extract, as the most potent extract, was used for the further biological and genotoxic studies. The results obtained indicated that diethyl ether extract of N. oleander leaves was the most potent extract, with LC50 of 10500 mg/l. The toxicity of the four extracts, using the LC50, at 10 °C was higher than that at 35 °C. The LC50 of diethyl ether extract significantly decreased the larval duration, pupal duration, percentage of pupation, percentage of adult emergence, longevity of females, fecundity, and oviposition activity index, whereas the growth index and the percentage of development per day of larvae and pupae were significantly increased compared to non-treated insects. Moreover, treatment with this extract induced significant dominant lethality in both male and female adults. It appears that diethyl ether extract of N. oleander leaves is potential control agent to Cx. pipiens.

  1. Ovicidal and adulticidal potential of leaf and seed extract of Albizia lebbeck (L.) Benth. (Family: Fabaceae) against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-05-01

    Several diseases are associated to the mosquito-human interaction. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus, and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. In the present study, hexane, benzene, chloroform, ethyl acetate, and methanol extracts of leaf and seed of Albizia lebbeck were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The mean percent hatchability of the eggs was observed after 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the methanol extract showed the highest ovicidal activity. One hundred percent mortality was observed at 250, 200, and 150 ppm for leaf methanol extract and 375, 300, and 225 ppm for seed methanol extract of A. lebbeck against C. quinquefasciatus, Ae. aegypti, and An. stephensi, respectively. The adulticidal activity of plant leaf and seed extracts showed moderate toxic effect on the adult mosquitoes after 24 h of exposure period. However, the highest adulticidal activity was observed in the leaf methanol extract of A. lebbeck against An. stephensi where the LC₅₀ and LC₉₀ values were 65.12 and 117.70 ppm, respectively. Compared to leaf extracts, seeds have low potency against three mosquito species. No mortality was recorded in the control. Our data suggest that the crude hexane, benzene, chloroform, ethyl acetate, and methanol solvent extracts of A. lebbeck have the potential to be used as an eco-friendly approach for the control of the An. stephensi, Ae. aegypti, and C. quinquefasciatus. These results suggest that the leaf and seed extracts have the potential to be used as an ideal

  2. Synthesis of silver and gold nanoparticles using Jasminum nervosum leaf extract and its larvicidal activity against filarial and arboviral vector Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Lallawmawma, H; Sathishkumar, Gnanasekar; Sarathbabu, Subburayan; Ghatak, Souvik; Sivaramakrishnan, Sivaperumal; Gurusubramanian, Guruswami; Kumar, Nachimuthu Senthil

    2015-11-01

    Silver and gold nanoparticles of Jasminum nervosum L. had unique optical properties such as broad absorbance band in the visible region of the electromagnetic spectrum. Characterization of the nanoparticles using UV spectrophotometer, Fourier transform infrared spectroscopy, X-ray diffraction, and transmission electron microscopy confirmed that the particles were silver (AgNPs) and gold (AuNPs) ranging between 4-22 and 2-20 nm with an average particles size of 9.4 and 10 nm, respectively. AgNPs and AuNPs of J. nervosum had high larvicidal activity on the filarial and arboviral vector, Culex quinquefasciatus, than the leaf aqueous extract. Observed lethal concentrations (LC50 and LC95) against the third instar larvae were 57.40 and 144.36 μg/ml for AgNPs and 82.62 and 254.68 μg/ml for AuNPs after 24 h treatment, respectively. The lethal time to kill 50% of C. quinquefasciatus larvae were 2.24 and 4.51 h at 150 μg/ml of AgNPs and AuNPs, respectively, while in the case of aqueous leaf extract of J. nervosum it was 9.44 h at 500 μg/ml (F 2,14 = 397.51, P < 0.0001). The principal component analysis plot presented differential clustering of the aqueous leaf extract, AgNP and AuNPs in relation to lethal dose and lethal time. It is concluded from the present findings that the biosynthesised AgNPs and AuNPs using leaf aqueous extract of J. nervosum could be an environmentally safer nanobiopesticide, and provided potential larvicidal effect on C. quinquefasciatus larvae which could be used for prevention of several dreadful diseases.

  3. Efectos de la competencia larval en los mosquitos de contenedores artificiales, Aedes aegypti y Culex pipiens (Diptera: Culicidae en condiciones semi-controladas

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    Analía FRANCIA

    2011-01-01

    Full Text Available Las larvas de los mosquitos Aedes aegypti (Linneo y Culex pipiens Linneo pueden criar conjuntamente en pequeños contenedores artificiales de agua, se genera así una competencia interespecífica y/o intraespecífica. El objetivo de este trabajo fue comparar la magnitud relativa de la competencia intra e interespecífica en A. aegypti y C. pipiens, generada durante el desarrollo larval en contenedores artificiales. Las variables medidas como respuesta fueron la supervivencia y el tiempo de desarrollo larval, y la biomasa total producida en estado de pupa. Se criaron larvas de ambos mosquitos en neumáticos de automóvil con agua declorinada y hojarasca. Se introdujeron larvas recién eclosionadas de acuerdo a la densidad (δ estimada según un censo previo de A. aegypti y C. pipiens. Se realizaron los siguientes tratamientos agregando larvas de: (1 A. aegypti hasta alcanzar δ A. aegypti determinada según el censo previo, (2 C. pipiens hasta δ C. pipiens del censo previo, (3 A. aegypti hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo, (4 C. pipiens hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo y (5 A. aegypti y C. pipiens hasta δ A. aegypti y δ C. pipiens del censo previo. Las tres variables medidas fueron afectadas por los tratamientos, excepto la supervivencia y la biomasa producida por C. pipiens. Aedes aegypti fue más alterada por la competencia intraespecífica que por la competencia interespecífica. En C. pipiens, la competencia interespecífica superó en sus efectos a la competencia intraespecífica. Existió asimetría competitiva, ya que C. pipiens fue más afectada por A. aegypti que lo contrario.

  4. Efficacy of larvicidal and pupicidal activity of Catharanthus roseus aqueous and solvent extracts against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Subarani, Selladurai; Sabhanayakam, Selvi; Kamaraj, Chinnaperumal; Elango, Gandhi; Kadir, Mohamed Abdul

    2013-08-01

    To investigate the larvicidal and pupicidal activities of aqueous, ethyl acetate and methanol extracts of Catharanthus roseus (C. roseus) against malaria and filariasis vectors. The larvicidal and pupicidal activities of C. roseus leaf extracts were tested against the fourth instar larvae and pupae of Anopheles stephensi (An. stephensi) and Culex quinquefasciatus (Cx. quinquefasciatus). The mortality was observed after 24 and 48 h post the treatment. The data were subjected to probit analysis to determine the lethal concentrations (LC50 and LC90) at which 50% and 90% of the treated larvae or pupae of the tested species were killed. The larval and pupal mortality were observed after 24 and 48 h of exposure of aqueous, ethyl acetate and methanol extracts of C. roseus; no mortality was observed in the control group. The LC50 values against the fourth-instar larvae of An. stephensi were 68.62 and 72.04 mg/mL for the aqueous extract, 82.47 mg/mL for the ethyl acetate extract, and 78.80 and 86.64 mg/mL for the methanol extract, while the aqueous, ethyl acetate and methanol extracts had LC50 values of 85.21, 76.84 and 94.20 mg/mL against the fourth-instar larvae of Cx. quinquefasciatus. The aqueous, ethyl acetate and methanol extracts had LC50 values of 118.08, 182.47 and 143.80 mg/mL against the pupae of An. stephensi and 146.20, 226.84 and 156.62 mg/mL against the pupae of Cx. quinquefasciatus, respectively. The aqueous and methanol extracts of C. roseus leaves had an excellent potential to control the malarial vector An. stephensi and filariasis vector Cx. quinquefasciatus. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  5. Effect of temperature on life history traits during immature development of Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) from Córdoba city, Argentina.

    Science.gov (United States)

    Grech, Marta G; Sartor, Paolo D; Almirón, Walter R; Ludueña-Almeida, Francisco F

    2015-06-01

    We investigated how ambient temperature under fluctuating conditions affects the larval-pupal immature traits of Aedes aegypti and Culex quinquefasciatus mosquitoes from Córdoba city, Argentina, and established each species development threshold and physiological time. Based on life tables, three cohorts of each mosquito species were reared in the laboratory under small fluctuating temperatures conditions of 15.2±1.7°C, 17.9±1.6°C, 21.6±0.7°C and 25.3±0.4°C for Ae. aegypti, and 16.6±1.7°C, 18.7±1.7°C and 25.2±0.3°C for Cx. quinquefasciatus. Immature development time and survival values, and also thermal development threshold and physiological time were estimated. Development times of all larval and pupal stages of Ae. aegypti and Cx. quinquefasciatus were significantly affected by the rearing temperatures, decreasing when temperature increased. Mean Ae. aegypti total (larva+pupa) development time ranged from 21.9 to 8.6 days, at 15.2 and 25.3°C, whereas, for Cx. quinquefasciatus varied between 23.5 to 9.2 days at 16.6 and 25.2°C, respectively. Larval and pupal survival of both species was affected by different rearing temperatures, increasing in general as temperature increased. For Ae. aegypti the total immature survival ranged from 26% at 15.2°C to 92% at 21.6°C; however, temperature did not have significant effect on this variable. The total immature survival of Cx. quinquefasciatus was significantly and positively affected by temperatures, ranging from 32 to 88%, at 16.6 and 25.2°C. The temperature development threshold and the physiological time estimated for Ae. aegypti and Cx. quinquefasciatus were 11.11°C and 93.74 degree-days, and 10.96°C and 136.87 degree-days, respectively. The results of the present study showed that temperature significantly affects the larval-pupal immature traits of these mosquito species of sanitary importance, from the central region of Argentina. All the parameters recorded are useful for the development of

  6. A Mixture of Bacillus thuringiensis subsp. israelensis With Xenorhabdus nematophila-Cultured Broth Enhances Toxicity Against Mosquitoes Aedes albopictus and Culex pipiens pallens (Diptera: Culicidae).

    Science.gov (United States)

    Park, Youngjin; Kyo Jung, Jin; Kim, Yonggyun

    2016-03-27

    XenorhabdusandPhotorhabdusspp. (Enterobacteriaceae) can synthesize and release secondary metabolites that play crucial roles in their pathogenicity by suppressing the immunity of target insects. The insect immunity contributes to defense against the pathogenicity ofBacillus thuringiensis(Bt). This study tested a hypothesis that bacterial immunosuppresants could enhance the susceptibility of mosquitoes (Aedes albopictusandCulex pipiens pallens) to Bt. Three symbiotic bacteria [X. nematophila(Xn),X. hominickii(Xh), andP. temperata temperata(Ptt)] were cultured in nutrient broth to allow them to produce secondary metabolites.Bacillus thuringiensis israelensis(BtI) was highly toxic to both culicid mosquitoes with median lethal concentration (LC50, spores/ml) of 2.9 × 105 and 2.2 × 105at 16 h after treatment, respectively. Addition of each bacteria-cultured broth enhanced BtI toxicity to these mosquito larvae. The LC50values of BtI toAe. albopictuslarvae were reduced to 1.5 × 105in Xn mixture, 1.7 × 105in Xh mixture, and 1.9 × 105 in Ptt mixture. The LC50values of BtI toCx. pipiens pallenslarvae were also reduced to 1.2 × 105in Xn mixture, 1.3 × 105in Xh mixture, and 1.5 × 105 in Ptt mixture. Adding benzylideneacetone or oxindole produced from Xn and Ptt also enhanced BtI toxicities to these mosquito larvae. Based on these results, we developed a new mosquitocidal Bt formulation called "Dip-Kill" consisting of 80% Xn-cultured broth, 10% BtI (1010spores/ml), and 10% preservative. Dip-Kill at 1,000 ppm was superior to a commercial BtI product at its recommended dose. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Larvicidal activity of Ipomoea cairica (L.) Sweet and Ageratina adenophora (Spreng.) King & H. Rob. plant extracts against arboviral and filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Samuel, Lallianrawna; Lalrotluanga; Muthukumaran, Rajendra Bose; Gurusubramanian, Guruswami; Senthilkumar, Nachimuthu

    2014-06-01

    Culex quinquefasciatus Say, an arboviral and filarial vector, is one of the most widespread mosquitoes in the world, and insecticide-resistant populations have been reported worldwide. Due to the emergence of resistance in C. quinquefasciatus plant based products or plant extracts may be alternative sources in integrated vector management program. The present study was carried out to establish the larvicidal activities of crude solvent extracts prepared from flowers and leaves of Ipomoea cairica and Ageratina adenophora against third instar larvae of C. quinquefasciatus as target species. The plant extracts were prepared with petroleum ether, chloroform and methanol solvents using sequential extraction method to determine the best extractant for subsequent isolation and characterization of active ingredient. The total yield of plant extract in the Soxhlet extraction ranged between 0.79% and 19.35%. The qualitative phytochemical study of the plant extracts from different solvents showed the presence of alkaloids, flavonoids, phenols, terpenes, saponins and tannins in different combinations. I. cairica and A. adenophora plant extracts were found to be effective against third instar larvae of C. quinquefasciatus causing 77-100% mortality at 48h. Highest mortality was observed at 500ppm and the order of larvicidal action was observed to be of methanol extract of I. cairica flower>petroleum ether extract of A. adenophora leaf>chloroform extract of I. cairica leaf. High mortality (100%) with low LC50 and LT50 were observed in methanolic flower extract (LC50 - 8.43ppm; LT50 - 2.51h at 48h) of I. cairica, and petroleum ether (LC50 - 133.56ppm; LT50 - 9.45h at 48h) leaf extract of A. adenophora. Lethal concentration (LC50 and LC90) values gradually decreased with the exposure periods, lethal time (LT50 and LT90) decreased with the concentration in bioassay experiment with the crude plant extracts. There was a significant correlation (three-way factorial ANOVA) was noticed

  8. Larvicidal, pupicidal, repellent and adulticidal activity of Citrus sinensis orange peel extract against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Murugan, Kadarkarai; Mahesh Kumar, Palanisamy; Kovendan, Kalimuthu; Amerasan, Duraisamy; Subrmaniam, Jayapal; Hwang, Jiang-Shiou

    2012-10-01

    Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikunguniya fever, West Nile virus and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The present study explored the effects of orange peel ethanol extract of Citrus sinensis on larvicidal, pupicidal, repellent and adulticidal activity against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. The orange peel material was shade dried at room temperature and powdered coarsely. From orange peel, 300 g powdered was macerated with 1 L of ethanol sequentially for a period of 72 h each and filtered. The yields of the orange peel ethanol crude extract of C. sinensis 13.86 g, respectively. The extracts were concentrated at reduced temperature on a rotary vacuum evaporator and stored at a temperature of 4 °C. The larvicidal, pupicidal and adult mortality was observed after 24 h of exposure; no mortality was observed in the control group. For C. sinensis, the median lethal concentration values (LC(50)) observed for the larvicidal and pupicidal activities against mosquito vector species A. stephensi first to fourth larval instars and pupae were 182.24, 227.93, 291.69, 398.00 and 490.84 ppm; A. aegypti values were 92.27, 106.60, 204.87, 264.26, 342.45, 436.93 and 497.41 ppm; and C. quinquefasciatus values were 244.70, 324.04, 385.32, 452.78 and 530.97 ppm, respectively. The results of maximum repellent activity were observed at 450 ppm in ethanol extracts of C. sinensis and the mean complete protection time ranged from 150 to 180 min was tested. The ethanol extract of C. sinensis showed 100% repellency in 150 min and showed complete protection in 90 min at 350 ppm against A. stephensi, A. aegypti and C. quinquefasciatus, respectively. The adult mortality was found in ethanol extract of C. sinensis with the LC(50) and LC(90) values of 272.19 and 457.14 ppm, A. stephensi; 289.62 and

  9. Mosquito larvicidal activity of thymol from essential oil of Coleus aromaticus Benth. against Culex tritaeniorhynchus, Aedes albopictus, and Anopheles subpictus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan; Rajeswary, Mohan; Veerakumar, Kaliyan

    2013-11-01

    Diseases transmitted by blood-feeding mosquitoes, such as dengue fever, dengue hemorrhagic fever, Japanese encephalitis, malaria, and filariasis, are increasing in prevalence, particularly in tropical and subtropical zones. To control mosquitoes and mosquito-borne diseases, which have a worldwide health and economic impacts, synthetic insecticide-based interventions are still necessary, particularly in situations of epidemic outbreak and sudden increases of adult mosquitoes. However, the indiscriminate use of conventional insecticides is fostering multifarious problems like widespread development of insecticide resistance, toxic hazards to mammals, undesirable effects on nontarget organisms, and environmental pollution. The aim of this research was to evaluate the toxicity of mosquito larvicidal activity of essential oil from Coleus aromaticus and its pure isolated constituent thymol against larvae of Culex tritaeniorhynchus, Aedes albopictus, and Anopheles subpictus. The chemical composition of the essential oil was analyzed using gas chromatography-mass spectroscopy. A total of 14 components of the essential oil of C. aromaticus were identified. The major chemical components identified were thymol (82.68%), terpinen-4-ol (3.2%), and trans-Caryophyllene (3.18%). Twenty-five early third instar larvae of C. tritaeniorhynchus, A. albopictus, and A. subpictus were exposed and assayed in the laboratory. Thymol and essential oil were tested in concentrations of 10, 20, 30, 40, and 50 and 30, 60, 90, 120, and 150 ppm, respectively. The larval mortality was observed after 24 h of treatment. The thymol had a significant toxic effect against early third-stage larvae of C. tritaeniorhynchus, A. albopictus, and A. subpictus with an LC50 values of 28.19, 24.83, and 22.06 μg/mL respectively, whereas the essential oil of C. aromaticus had an LC50 values of 72.70, 67.98, and 60.31 μg/mL, respectively. No mortality was observed in controls. The Chi-square values were significant

  10. Bionomics of Anopheles quadrimaculatus and Culex erraticus (Diptera: Culicidae) in the Falls Lake basin, North Carolina: seasonal changes in abundance and gonotrophic status, and host-feeding patterns.

    Science.gov (United States)

    Robertson, L C; Prior, S; Apperson, C S; Irby, W S

    1993-07-01

    Larval and adult Anopheles quadrimaculatus Say (sensu lato) and Culex erraticus (Dyar & Knab) were collected at Falls of the Neuse Lake (Falls Lake) in North Carolina from May 1985 to December 1986. Adult mosquitoes were aspirated weekly from shelters in woodlands adjacent to larval sampling sites. An. quadrimaculatus and Cx. erraticus comprised > 95% of the total number of mosquitoes collected. An. quadrimaculatus adults exhibited vernal and autumnal peaks of abundance during both years. Cx. erraticus adults exhibited several peaks of abundance in summer and early fall of both years. An. quadrimaculatus initiated blood feeding in May and April 1985 and 1986, respectively. Only unfed females were found in late fall and winter. Cx. erraticus initiated blood feeding earlier than An. quadrimaculatus. In 1985, approximately 25% of the females in the first collection in May contained a blood meal, whereas in 1986, approximately 10% of the females in the first collection in April were blood fed. Females of both species ceased blood feeding in late fall. Larvae were sampled on a weekly basis from lake edge, flood plain, and creek edge habitats. Generally, An. quadrimaculatus larvae were most abundant in lake edge and flood plain habitats, whereas Cx. erraticus larvae were most abundant in the creek edge habitat. The population dynamics of An. quadrimaculatus were associated with seasonal changes in the level of Falls Lake. In 1985 and 1986, the level of Falls Lake gradually declined from May to mid-August until heavy rainfall caused a 1-m rise in lake level. Populations of An. quadrimaculatus larvae and adults increased significantly following the rise in the level of Falls Lake. In contrast, the abundance of larval and adult Cx. erraticus decreased with rising lake levels in late August. Water level management should be an effective method for controlling populations of An. quadrimaculatus but not for Cx. erraticus. Blood-fed mosquitoes were tested to identify bloodmeal

  11. Green synthesis of silver nanoparticles using Sida acuta (Malvaceae) leaf extract against Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2013-12-01

    Mosquitoes act as a vector for most of the life-threatening diseases like malaria, yellow fever, dengue fever, chikungunya fever, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management, emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain, and adverse effects on environmental quality and nontarget organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are nontoxic, easily available at affordable prices, biodegradable, and show broad-spectrum target-specific activities against different species of vector mosquitoes. In the present study, the larvicidal activity of silver nanoparticles (AgNPs) synthesized using Sida acuta plant leaf extract against late third instar larvae of Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti was determined. Range of concentrations of synthesized AgNPs (10, 20, 30, 40, and 50 μg/mL) and aqueous leaf extract (50, 100, 150, 200, and 250 μg/mL) were tested against the larvae of C. quinquefasciatus, A. stephensi and A. aegypti. The synthesized AgNPs from S. acuta leaf were highly toxic than crude leaf aqueous extract in three important vector mosquito species. The results were recorded from UV-Vis spectrum, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis. Larvae were exposed to varying concentrations of aqueous crude extract and synthesized AgNPs for 24 h. Considerable mortality was evident after the treatment of S. acuta for all three important vector mosquitoes. The LC50 and LC90 values of S. acuta aqueous leaf extract appeared to be most effective

  12. Analysis of the interspecific association between larvae of Culex pipiens and Culex quinquefasciatus, the common and medically important mosquito species (Diptera: Culicidae in Hail Region, Kingdom of Saudi Arabia

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    Mohamed Amin Kenawy

    2017-11-01

    Full Text Available Objective: To examine the extent of the interspecific association between Culex pipiens and Culex quinquefasciatus in Hail Region, Saudi Arabia with an aim of further understanding the ecology of such mosquito larvae mainly in respect to similarity in their breeding requirements. Methods: Larvae were collected by dipping over one year from breeding sites in nine localities in Hail Region. The degree of the interspecific association between larvae of the two mosquito species was measured on the basis of presence-absence data (Coefficient of Interspecific Association, CAB ± SD and on their relative numbers (Index of Association or Sorensen's coefficient, I. Results: The two species had a significantly moderate association (CAB = 0.21, P < 0.05 and I = 0.39. The Sorensen’s coefficient (I showed monthly variation and was directly related to the separate/compiled abundance of the two species (b = 0.01–0.02. Conclusions: The obtained results may indicate that the habitat requirements and preference of the two species are similar and that their abundance influencing the degree of their interspecific association.

  13. Aspectos da distribuição de Culex (Culex quinquefasciatus Say (Diptera, Culicidae na região do rio Pinheiros, na cidade de São Paulo, Estado de São Paulo, Brasil Aspects of the distribution of Culex (Culex quinquefasciatus Say (Diptera, Culicidae in the region of the Pinheiros River, in the city of São Paulo, State of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Sirlei Antunes de Morais

    2006-09-01

    Full Text Available A distribuição de Culex (Culex quinquefasciatus Say (1823 ao longo das margens do rio Pinheiros e os principais fatores que levam à proliferação da espécie foram estudados efetuando-se coletas semanais de mosquitos adultos, no período de um ano, em três pontos eqüidistantes às margens do rio. Para as coletas de mosquitos utilizou-se aspirador à bateria, por um período de cinco minutos. Os mosquitos foram identificados, diferenciados segundo o sexo e contados. Para verificação do estado fisiológico, as fêmeas foram separadas em vazias, com sangue e com ovos. Foram coletados 35.684 mosquitos, todos identificados como Cx. quinquefasciatus, sendo 39,4% fêmeas e 60,6% machos. As freqüências tomaram proporções diferentes entre os pontos de coletas e, em uma série temporal. O ambiente impactado do rio Pinheiros representa um excelente criadouro de Cx. quinquefasciatus, confirmado pela ocorrência de picos acentuados na freqüência de mosquitos, com desenvolvimento de forma explosiva e sobreposições entre as gerações, após as chuvas e em épocas de verão.The distribution of Culex (Culex quinquefasciatus Say (1823 along of the margins of the Pinheiros river and the main factors that lead to the proliferation of the species were studied doing weekly collections of adult mosquitoes, in the period of one year, in three equidistant points in the margins of the river. For the collections of mosquitoes battery vacuum cleaner was used, for a period of five minutes. The mosquitoes were identified, differentiated according to the sex and counted. For verification of the physiological state, the females were differentiated in empty, with blood or eggs. A total of 35.684 mosquitoes were captured, all of them were identified as Cx. quinquefasciatus, being 39.4% females and 60.6% males. The frequencies took different proportions between the points of collections and in a temporary series. The damaged environment of the Pinheiros river

  14. Ecology of mosquitoes (Diptera, Culicidae) in natural and artificial rural breeding sites in northern Paraná State, Brazil: VIII. The influence of predator larvae (Toxorhynchites sp., Limatus durhamii and Culex bigoti) on the populations of Culex quinquefasciatus and Culex eduardoi

    OpenAIRE

    José Lopes

    1999-01-01

    Larvae of Culex eduardoi, Culex bigoti, Limatus durhamii and Toxorhynchites were collected in a tyre that had been placed in a wood by a river bank. These larvae were present coexisting and in an individualized form. It was observed that Toxorhynchites, Culex bigoti and Limatus durhamii were efficient in reducing the other two species's population. Culex bigoti and Toxorhynchites showed preference for Culex quinquefasciatus larvae, while Limatus durhamii preferred Culex eduardoi. The most eff...

  15. Cubiertas de auto abandonadas como sitios de cría de Culex eduardoi (Diptera: Culicidae en el Parque Provincial Pereyra Iraola, Provincia de Buenos Aires Discarded car tires as breeding sites of Culex eduardoi (Diptera: Culicidae in the Pereyra Iraola Provincial Park, Buenos Aires Province

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    Alejandra Rubio

    2011-06-01

    Full Text Available El conocimiento sobre la fauna de mosquitos que se cría en cubiertas de auto es realmente escaso en Argentina. El objetivo de este estudio fue caracterizar una población de inmaduros de Culex eduardoi Casal & Garcia en una acumulación de cubiertas abandonadas en un bosque suburbano de la Provincia de Buenos Aires. Entre noviembre 2009 y mayo 2010, se recolectaron mensualmente larvas de mosquitos en 27 cubiertas de auto abandonadas en un sector boscoso del Parque Provincial Pereyra Iraola. Se recolectaron en total 1.009 larvas del tercer y cuarto estadio de Cx. eduardoi, y el índice de contenedores (IC global fue 66,3% (106/160. Culex eduardoi estuvo presente durante todos los meses, aunque el IC difirió significativamente (x²(6 = 15,11; p The knowledge about tire-breeding mosquitoes is truly scarce in Argentina. The objective of this study was to characterize a population of immatures of Culex eduardoi Casal & Garcia, from a pile of abandoned tires located in a suburban forest of Buenos Aires Province. Between November 2009 and May 2010, mosquito larvae were monthly collected in 27 abandoned tires within a woody area of the Parque Provincial Pereyra Iraola. A total of 1009 third and fourth instar larvae of Cx. eduardoi were collected, and the overall container index (CI was 66.3% (106/160. Culex eduardoi was collected every month but the CI differed significantly (x²(6 = 15.11; p < 0.05, reaching maximum values in November and December (76 and 92.5% respectively. In spring, the relative abundance of larvae was also the highest, and the mean number of larvae collected per habitat was 9.5 (min. 3.5 in March; max.15.1 in November. Other mosquito species such as Cx. pipiens Linneo and Toxorhynchites theobaldi Dyar & Knab were also found in the studied containers. The present findings contribute with novel knowledge on culicids of tires in Argentina.

  16. Crowdsourcing for large-scale mosquito (Diptera: Culicidae) sampling

    Science.gov (United States)

    Sampling a cosmopolitan mosquito (Diptera: Culicidae) species throughout its range is logistically challenging and extremely resource intensive. Mosquito control programmes and regional networks operate at the local level and often conduct sampling activities across much of North America. A method f...

  17. Efectos de la competencia larval en los mosquitos de contenedores artificiales, Aedes aegypti y Culex pipiens (Diptera: Culicidae en condiciones semi-controladas Effects of larval competition between the container mosquitoes, Aedes aegypti and Culex pipiens (Diptera: Culicidae in semi-controlled conditions

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    Analía Francia

    2011-12-01

    Full Text Available Las larvas de los mosquitos Aedes aegypti (Linneo y Culex pipiens Linneo pueden criar conjuntamente en pequeños contenedores artificiales de agua, se genera así una competencia interespecífica y/o intraespecífica. El objetivo de este trabajo fue comparar la magnitud relativa de la competencia intra e interespecífica en A. aegypti y C. pipiens, generada durante el desarrollo larval en contenedores artifi ciales. Las variables medidas como respuesta fueron la supervivencia y el tiempo de desarrollo larval, y la biomasa total producida en estado de pupa. Se criaron larvas de ambos mosquitos en neumáticos de automóvil con agua declorinada y hojarasca. Se introdujeron larvas recién eclosionadas de acuerdo a la densidad (5 estimada según un censo previo de A. aegypti y C. pipiens. Serealizaron los siguientes tratamientos agregando larvas de: (1 A. aegypti hasta alcanzar δ A. aegypti determinada según el censo previo, (2 C. pipiens hasta δ C. pipiens del censo previo, (3 A. aegypti hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo, (4 C. pipiens hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo y (5 A. aegypti y C. pipiens hasta δ A. aegypti y δ C. pipiens del censo previo. Las tres variables medidas fueron afectadas por los tratamientos, excepto la supervivencia y la biomasa producida por C. pipiens. Aedes aegypti fue más alterada por la competencia intraespecífica que por la competencia interespecífica. En C. pipiens, la competencia interespecífica superó en sus efectos a la competencia intraespecífica. Existió asimetría competitiva, ya que C. pipiens fue más afectada por A. aegypti que lo contrario.Larvae of Aedes aegypti (Linneo and Culex pipiens Linneo may develop together in small artificial water containers, promoting inter- and/or intra-specific competition. Our aim was to compare the relative importance of interspecific and intraspecific competition in both species during

  18. Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae

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    Mário Luís Pessôa Guedes

    2014-03-01

    Full Text Available Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae. Considering that some species of Culicidae are vectors of pathogens, both the knowledge of the diversity of the mosquito fauna and how some environment factors influence in it, are important subjects. In order to address the composition of Culicidae species in a forest reserve in southern Atlantic Forest, we compared biotic and abiotic environmental determinants and how they were associated with the occurrence of species between sunset and sunrise. The level of conservation of the area was also considered. The investigation was carried out at Reserva Natural do Morro da Mina, in Antonina, state of Paraná, Brazil. We performed sixteen mosquito collections employing Shannon traps at three-hour intervals, from July 2008 to June 2009. The characterization of the area was determined using ecological indices of diversity, evenness, dominance and similarity. We compared the frequency of specimens with abiotic variables, i.e., temperature, relative humidity and pluviosity. Seven thousand four hundred ten mosquito females were captured. They belong to 48 species of 12 genera. The most abundant genera were Anopheles, Culex, Coquillettidia, Aedes and Runchomyia. Among the species, the most abundant was Anopheles cruzii, the primary vector of Plasmodium spp. in the Atlantic Forest. Results of the analyses showed that the abiotic variables we tested did not influence the occurrence of species, although certain values suggested that there was an optimum range for the occurrence of culicid species. It was possible to detect the presence of species of Culicidae with different epidemiologic profiles and habitat preference.

  19. α-Humulene and β-elemene from Syzygium zeylanicum (Myrtaceae) essential oil: highly effective and eco-friendly larvicides against Anopheles subpictus, Aedes albopictus, and Culex tritaeniorhynchus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Benelli, Giovanni

    2016-07-01

    Mosquitoes transmit serious pathogens and parasites to humans and animals, including malaria, dengue, Japanese encephalitis and filariasis. The extensive use of chemical pesticides leads to the development of resistance in mosquito vector populations and serious non-target effects on human health and the environment. Myrtaceae plants can be a useful reservoir of natural products effective against Culicidae young instars. In this research, we evaluated the mosquitocidal potential of the essential oil (EO) from Syzygium zeylanicum leaves against larvae of three mosquitoes of medical and veterinary importance, the malaria vector Anopheles subpictus, the dengue vector Aedes albopictus, and the Japanese encephalitis vector Culex tritaeniorhynchus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the S. zeylanicum EO contained at least 18 compounds. The major chemical components were α-humulene (37.8.5 %) and β-elemene (10.7 %). The EO had a significant toxic effect against early third-stage larvae of An. subpictus, Ae. albopictus, and Cx. tritaeniorhynchus, with LC50 values of 83.11, 90.45, and 97.96 μg/ml, respectively. The two major constituents extracted from the S. zeylanicum EO were tested individually for acute toxicity against larvae of the three mosquito vectors. α-Humulene and β-elemene appeared highly effective against An. subpictus (LC50 = 6.19 and 10.26 μg/ml, respectively), followed by Ae. albopictus (LC50 = 6.86 and 11.15 μg/ml) and Cx. tritaeniorhynchus (LC50 = 7.39 and 12.05 μg/ml). Furthermore, the EO and its major components was safe towards the non-target fish Gambusia affinis; LC50 values were 20374.26, 1024.95, and 2073.18 μg/ml, respectively for EO, α-humulene and β-elemene. Overall, this study highlighted that the acute toxicity of S. zeylanicum EO towards mosquito larvae was mainly due to the presence of α-humulene and β-elemene. Furthermore, we pointed

  20. Mosquitoes (Diptera: Culicidae) From the Northwestern Brazilian Amazon: Padauari River.

    Science.gov (United States)

    Hutchings, R S G; Hutchings, R W; Menezes, I S; Motta, M de A; Sallum, M A M

    2016-11-01

    The mosquito fauna (Culicidae) from remote northern areas of the State of Amazonas were sampled using Centers for Disease Control and Prevention, Shannon, Malaise, and Suspended traps, together with net sweeping and immature collections. One hundred and seven collections were performed in five localities along the Padauari River, State of Amazonas, Brazil, during June 2010. The 20,557 mosquitoes collected are distributed in 17 genera, representing 117 different species, of which four are new distributional records for the State of Amazonas. Furthermore, there are 10 morphospecies that may represent undescribed new taxa, eight of which are also new records for the State of Amazonas. The genus Culex had the highest number of species and the largest number of individuals. Aedes and Psorophora both represented 10% of the total sample and had the second highest number of species and individuals. The most abundant species was Culex (Melanoconion) gnomatos Sallum, Hutchings & Ferreira, followed by Aedes (Ochlerotatus) fulvus (Wiedemann), Culex (Melanoconion) vaxus Dyar, Culex (Melanoconion) portesi Senevet & Abonnenc, Psorophora (Janthinosoma) amazonica Cerqueira, Culex (Culex) mollis Dyar & Knab, Psorophora (Janthinosoma) albigenu (Peryassú), and Culex (Melanoconion) theobaldi Lutz. The epidemiological and ecological implications of mosquito species found are discussed and are compared with other mosquito inventories from the Amazon region. The results represent the most diverse standardized inventory of mosquitoes along the Padauari River, with the identification of 127 species-level taxa distributed in five localities, within two municipalities (Barcelos and Santa Isabel do Rio Negro). © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Incorporación de larvas de mosquito Culex stigmatosoma (Diptera:Culicidae) en la dieta del pez cebra Brachidanio rerio (Pisces:Cyprinidae) y su efecto en la reproducción

    OpenAIRE

    J. Luna-Figueroa

    2007-01-01

    En la acuicultura, un aspecto de gran importancia es la nutrición. En especies potencialmente cultivables, como el pez cebra Brachidanio rerio, es importante conocer los requerimientos nutricionales para maximizar su reproducción. Las larvas de mosquito son una alternativa viable como alimento vivo en la dieta de peces. Por lo que, en la presente investigación, se evaluó el efecto de la incorporación de larvas de Culex stigmatosoma en la dieta del pez cebra mediante...

  2. Cyt1Ab1 and Cyt2Ba1 from Bacillus thuringiensis subsp. medellin and B. thuringiensis subsp. israelensis Synergize Bacillus sphaericus against Aedes aegypti and Resistant Culex quinquefasciatus (Diptera: Culicidae)

    Science.gov (United States)

    Wirth, Margaret C.; Delécluse, Armelle; Walton, William E.

    2001-01-01

    The interaction of two cytolytic toxins, Cyt1Ab from Bacillus thuringiensis subsp. medellin and Cyt2Ba from Bacillus thuringiensis subsp. israelensis, with Bacillus sphaericus was evaluated against susceptible and resistant Culex quinquefasciatus and the nonsensitive species Aedes aegypti. Mixtures of B. sphaericus with either cytolytic toxin were synergistic, and B. sphaericus resistance in C. quinquefasciatus was suppressed from >17,000- to 2-fold with a 3:1 mixture of B. sphaericus and Cyt1Ab. This trait may prove useful for combating insecticide resistance and for improving the activity of microbial insecticides. PMID:11425753

  3. Mosquito Fauna (Diptera: Culicidae) of Hamedan County, Western Iran.

    Science.gov (United States)

    Zahirnia, Amir Hossein; Zendehfili, Hamid

    2014-12-01

    This study aimed to identify and determine the larval and adult mosquitoes (Culicidae) fauna in Hamedan County, western Iran. It was a cross-sectional study which took place in four area of the Hamedan County. Sampling methods for larvae, pupae and adults were dipping, hand catch, night catch and total catch. Larvae and adult mosquitoes collected and were sent to laboratory of Medical Entomology, Hamedan University of Medical Sciences, Hamedan, Iran for further identification to species level to determination of fauna. Data analysis was performed using SPSS software version19. Three genera and eight species of family Culicidae were collected and identified in Hamedan County, Hamedan Province, West Iran, during May to October 2013. These species included: Culex theileri, Cx. pipiens, Cx. antennatus, Culiseta subochrea, Cs. langiareolata, Anopheles superpictus, An. maculipennis and An. stephensi. The species Cx. antennatus and An. stephensi were reported for the first time in Hamedan County. An. stephensi and Cx. antennatus caught had not been previously recorded in Hamedan Province. Due to vast agricultural activities in the province which provides suitable environment for the establishment of various species of mosquitoes and since many of them are potential vectors of human and domesticated animal pathogens, their ecology needs to be studied extensively.

  4. [Evaluation of the triflumuron and the mixture of Bacillus thuringiensis plus Bacillus sphaericus for control of the immature stages of Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) in catch basins].

    Science.gov (United States)

    Giraldo-Calderón, Gloria I; Pérez, Mauricio; Morales, Carlos A; Ocampo, Clara B

    2008-06-01

    In Cali, Colombia, catch basins (streetside storm drains) are one of the main larval habitats of Aedes aegypti and Culex quinquefasciatus. Since 1999, these mosquitoes have been controlled by the Secretaría de Salud Municipal (Secretary of Municipal Public Health) using the larvicide triflumuron. Because of high densities of these mosquitoes that remain in the city, treatment failure was suspected -possibly insecticide resistance of the target species. The efficacy of triflumuron and VectoMax (biorational mixture of Bacillus thuringiensis var. israelensis plus Bacillus sphaericus) were evaluated in the control of A. aegypti and C. quinquefasciatus in catch basins. The residual effect of a single application of the biorational formulation was determined in catch basins during periods of high and low rainfall. The efficacy of the products was measured in 60 catch basins located in a residential neighborhood of Cali for a period of 90 days. The mean number of immature instars (A. aegypti and C. quinquefasciatus larvae and pupae of both species) was determined biweekly from 40 catch basins with insecticide intervention (20 treated with triflumuron, 20 with VectoMax) and 20 untreated (control group). The residual effect of the biorational larvicide was evaluated biweekly in 10 catch basins during each of the 2 climatic periods. Results. The catch basins treated with VectoMax presented a significantly lower mean number of immature instars of both species compared with the control ( p<0.01). In contrast, the triflumuron treatment significantly reduced only immature instars of A. aegypti compared with the control ( p<0.001). The residual effect of VectoMax was higher during low rainfall compared to the control ( p<0.001). Conclusion. The biorational formulation was the more effective treatment for the control of both species during the period of evaluation (15 days).

  5. Incorporación de larvas de mosquito Culex stigmatosoma (Diptera:Culicidae en la dieta del pez cebra Brachidanio rerio (Pisces:Cyprinidae y su efecto en la reproducción

    Directory of Open Access Journals (Sweden)

    J. Luna-Figueroa

    2007-01-01

    Full Text Available En la acuicultura, un aspecto de gran importancia es la nutrición. En especies potencialmente cultivables, como el pez cebra Brachidanio rerio, es importante conocer los requerimientos nutricionales para maximizar su reproducción. Las larvas de mosquito son una alternativa viable como alimento vivo en la dieta de peces. Por lo que, en la presente investigación, se evaluó el efecto de la incorporación de larvas de Culex stigmatosoma en la dieta del pez cebra mediante la producción de huevos y la sobrevivencia. Los resultados indican que la producción de huevos difirió 64.40% entre los peces nutridos con Cx. stigmatosoma (570.98 ± 179.16 y con alimento comercial (203.22 ± 32.88 (p 0.05. La máxima producción de huevos (908 se obtuvo en hembras con un peso húmedo promedio de 1,170 mg, alimentadas con larvas de Cx. stigmatosoma, mientras que la mínima producción (140 huevos en las hembras, con un peso húmedo promedio de 1,254 mg, utilizando alimento comercial. La sobrevivencia de los reproductores fue del 100%. En el caso de las crías, la mayor sobrevivencia (88.22% fue registrada en los peces alimentados con larvas de Cx. stigmatosoma (p < 0.001. Los resultados ponderan la relación entre las altas tasas de reproducción y sobrevivencia de B. rerio, así como el potencial económico del cultivo mediante la incorporación de larvas de Cx. stigmatosoma en su dieta.

  6. Mosquitoes (Diptera: Culicidae) of metropolitan Hamburg, Germany.

    Science.gov (United States)

    Krüger, A; Börstler, J; Badusche, M; Lühken, R; Garms, R; Tannich, E

    2014-08-01

    In Europe, mosquito-related public health concerns are growing due to the increasing spread of invasive mosquito species and the recent emergence of mosquito-borne arboviruses. A vital backbone in the assessment of these issues is detailed knowledge of the mosquito fauna, i.e. regional mosquito inventories. It was therefore decided to intensify nationwide investigations on the occurrence and distribution of mosquitoes in Germany in order to update old records and to detect possible faunal changes. This paper is focussing on a densely populated metropolitan region, the federal state of Hamburg and its adjacent environs, taking two historical baseline inventories into consideration, spanning almost 100 years of mosquito research in Hamburg. In the period between 2010 and 2014, more than 10,000 juvenile, neonate and adult mosquito specimens were sampled and trapped at 105 sites in Hamburg and its environs, of which about 60% have been identified to species level, resulting in a total of 33 recorded species. Of these, Anopheles algeriensis, Culex modestus, Ochlerotatus caspius, Ochlerotatus nigrinus and Ochlerotatus sticticus are new to the area. The most common species in Hamburg are Culex pipiens/torrentium and Ochlerotatus annulipes/cantans. In contrast, two previously common species, Anopheles atroparvus and Ochlerotatus excrucians, were not detected. Despite substantial environmental changes due to reconstruction, urbanisation and renaturation in the Hamburg metropolitan region in recent decades, there has been remarkably little change within the mosquito fauna during the last century.

  7. Laboratory Studies of Larval Cannibalism in ’Toxorhynchites amboinensis’ (Diptera: Culicidae)

    Science.gov (United States)

    1990-09-01

    AD-A233 327 LABORATORY STUDIES OF LARVAL CANNIBALISM IN TOXORHYNCHITES ANfSOIENSIS (DIPTERA: CULICIDAE) Barry Annis, Umi T. Bismo Sarojo, Masir...and Development Command for Work Unit 3M161102BS10.AD410. --------------------------------------------------- Distribution of this document is...unlimited. J.C. COOLBAUGH CAPT MSC USN Commanding Officer fH., D TR-1090 Laboratory Studies of Larval Cannibalism in Toxorhynchites amboinensis (Diptera

  8. Experimental Transmission of Venezuelan Equine Encephalomyelitis Virus by a Strain of Aedes albopictus (Diptera: Culicidae) from New Orleans, Louisiana

    Science.gov (United States)

    1992-09-01

    2). However, the strains of Aedes albopictus (Diptera: Culicidae) col- greater susceptibility of the Brazilian strains than lected in North and South...AD-A259 565 Experimental Transmission of Venezuelan Equine Encephalomyelitis Virus by a Strain of Aedes albopictus (Diptera: Culicidae) S1 ls from... susceptibility of’ selected strains of’ Ecuador and Peru in northern South America Ac. albopictus for VEE and CHIK viruses to de- and as far north as southern

  9. Permethrin and malathion LD90 values for Culex quinquefasciatus vary with tropical application site

    Science.gov (United States)

    Prior research with multiple insect species has demonstrated variation between the mortality associated with an insecticide and the location of exposure on the insect body. This variation has been demonstrated in Culex quinquefasciatus Say (Diptera: Culicidae), but it has not been quantified using a...

  10. Effects of an aqueous extract of Azadirachta indica on the groCulex ...

    African Journals Online (AJOL)

    The neem tree Azadirachta indica Juss (Meliaceae) is one of the most studied plant species for pest control, including mosquitoes. However, the effect of aqueous neem seed extracts (ANSE) on each of the 4 instars of mosquito Culex quinquefasciatus Say (Diptera: Culicidae) is unknown. In order to determine the effect of ...

  11. Random Amplified Polymorphic DNA (RAPD) Markers Readily Distinguish Cryptic Mosquito Species (Diptera: Culicidae: Anopheles)

    Science.gov (United States)

    1993-01-01

    DNA isolation. Individual larvae or adults were ground with a strong diagnostic bands and simple patterns. Primers pro- plastic pestle in...V. (1988) Com- peninsular Malaysia and Thailand (Diptera: Culicidae). Mosq parison of DNA probe and cytogenic methods for identifying field Syst 20

  12. The Brazilian Malaria Vector Anopheles (Kerteszia) Cruzii: Life Stages and Biology (Diptera: Culicidae)

    Science.gov (United States)

    1991-11-01

    F.T. de SB. 1969b. Estudo da longevidade do Anopheies (Kerteszia) cruzii e do Anopheles (Kerteszia) bellator em condiNes naturais. Rev. Bras...and A.M. Zavortink, TJ. 1973. Mosquito studies (Diptera, Borba. 1977. Sobre a longevidade de Anophe- Culicidae). XXIX. A review of the subgenus les

  13. Mosquitoes (Diptera: Culicidae) and their relevance as disease vectors in the city of Vienna, Austria.

    Science.gov (United States)

    Lebl, Karin; Zittra, Carina; Silbermayr, Katja; Obwaller, Adelheid; Berer, Dominik; Brugger, Katharina; Walter, Melanie; Pinior, Beate; Fuehrer, Hans-Peter; Rubel, Franz

    2015-02-01

    Mosquitoes (Diptera: Culicidae) are important vectors for a wide range of pathogenic organisms. As large parts of the human population in developed countries live in cities, the occurrence of vector-borne diseases in urban areas is of particular interest for epidemiologists and public health authorities. In this study, we investigated the mosquito occurrence in the city of Vienna, Austria, in order to estimate the risk of transmission of mosquito-borne diseases. Mosquitoes were captured using different sampling techniques at 17 sites in the city of Vienna. Species belonging to the Culex pipiens complex (78.8 %) were most abundant, followed by Coquillettidia richiardii (10.2 %), Anopheles plumbeus (5.4 %), Aedes vexans (3.8 %), and Ochlerotatus sticticus (0.7 %). Individuals of the Cx. pipiens complex were found at 80.2 % of the trap sites, while 58.8 % of the trap sites were positive for Cq. richiardii and Ae. vexans. Oc. sticticus was captured at 35.3 % of the sites, and An. plumbeus only at 23.5 % of the trap sites. Cx. pipiens complex is known to be a potent vector and pathogens like West Nile virus (WNV), Usutu virus (USUV), Tahyna virus (TAHV), Sindbis virus (SINV), Plasmodium sp., and Dirofilaria repens can be transmitted by this species. Cq. richiardii is a known vector species for Batai virus (BATV), SINV, TAHV, and WNV, while Ae. vexans can transmit TAHV, USUV, WNV, and Dirofilaria repens. An. plumbeus and Oc. sticticus seem to play only a minor role in the transmission of vector-borne diseases in Vienna. WNV, which is already wide-spread in Europe, is likely to be the highest threat in Vienna as it can be transmitted by several of the most common species, has already been shown to pose a higher risk in cities, and has the possibility to cause severe illness.

  14. New records of mosquitoes (Diptera: Culicidae from Misiones Province, Argentina

    Directory of Open Access Journals (Sweden)

    Gustavo C. ROSSI

    2014-01-01

    Full Text Available Las siguientes especies representan el primer registro de la Argentina: Culex (Anoedioporpa canaanensis Lane & Withman, Culex (Anoedioporpa originator Gordon & Evans, Culex (Culex declarator Dyar & Knab, Culex (Melanoconion ribeirensis Forattini & Sallum, Culex (Microculex neglectus Lutz, Culex (Microculex pleuristriatus Lutz, Orthopodomyia fascipes Coquillett y Wyeomyia (Wyeomyia medioalbipes Lutz. Las especies Anopheles (Nyssorhynchus guarani Shannon y Ochlerotatus (Ochlerotatus rhyacophilus (Da Costa Lima fueron recientemente rescatadas de la sinonimia de Anopheles (Nyssorhynchus lutzii Cruz y Ochlerotatus (Ochlerotatus scapularis (Rondani. Las siguientes especies corresponden a nuevos registros de la provincia de Misiones: Anopheles (Anopheles neomaculipalpus Curry, Coquillettidia (Rhynchotaenia fasciolata (Lynch Arribalzaga, Culex (Culex acharistus Root, Culex (Culex tatoi Casal & García, Culex (Culex usquatus Dyar y Toxorhynchites (Lynchiella guadeloupensis (Dyar & Knab. Con estos nuevos registros el número de especies citadas se eleva a 189 de la provincia de Misiones y 242 de Argentina.

  15. Identification of Belgian mosquito species (Diptera: Culicidae) by DNA barcoding.

    Science.gov (United States)

    Versteirt, V; Nagy, Z T; Roelants, P; Denis, L; Breman, F C; Damiens, D; Dekoninck, W; Backeljau, T; Coosemans, M; Van Bortel, W

    2015-03-01

    Since its introduction in 2003, DNA barcoding has proven to be a promising method for the identification of many taxa, including mosquitoes (Diptera: Culicidae). Many mosquito species are potential vectors of pathogens, and correct identification in all life stages is essential for effective mosquito monitoring and control. To use DNA barcoding for species identification, a reliable and comprehensive reference database of verified DNA sequences is required. Hence, DNA sequence diversity of mosquitoes in Belgium was assessed using a 658 bp fragment of the mitochondrial cytochrome oxidase I (COI) gene, and a reference data set was established. Most species appeared as well-supported clusters. Intraspecific Kimura 2-parameter (K2P) distances averaged 0.7%, and the maximum observed K2P distance was 6.2% for Aedes koreicus. A small overlap between intra- and interspecific K2P distances for congeneric sequences was observed. Overall, the identification success using best match and the best close match criteria were high, that is above 98%. No clear genetic division was found between the closely related species Aedes annulipes and Aedes cantans, which can be confused using morphological identification only. The members of the Anopheles maculipennis complex, that is Anopheles maculipennis s.s. and An. messeae, were weakly supported as monophyletic taxa. This study showed that DNA barcoding offers a reliable framework for mosquito species identification in Belgium except for some closely related species. © 2014 John Wiley & Sons Ltd.

  16. Molecular Phylogeny of Neotropical Anopheles (Nyssorhynchus) albitarsis Species Complex (Diptera: Culicidae)

    Science.gov (United States)

    2005-11-01

    Museum, Department of7.ool0l(y, Cromwell Rd.• London 5W75Bo. United KinJ(dom. 1 Nlicleo de Pesquisas Taxon&nica e Sistemdtica em Entomologia M~ica...Lynch.Arribalzaga 1878 (Diptera: Culicidae) includin~ from the type 10<.".11. ity, Barndero, Argentina . Mem. Inst. Oswaldo Cruz 85: 275-290...Culicidae) from Parolguay, Argentina , and Brazil. J. Mcd. Elltomol. 32: 697-704. Receiced 15 l:ebnlartj 200.’; lUX~."tet/ 28 July 2005.

  17. Mosquitoes (Diptera, Culicidae inhabiting foliar tanks of Guzmania brasiliensis Ule (Bromeliaceae in central Amazonia, Brazil

    Directory of Open Access Journals (Sweden)

    Sharlene Roberta da Silva Torreias

    2010-01-01

    Full Text Available Mosquitoes in the family Culicidae develop their immature forms in different environments depending on various circumstances. This study represents the first contribution to the ecological knowledge of culicids living in the bromeliad G. brasiliensis. The objectives of the study were to compare the Culicidae fauna of bromeliads in two seasonal periods, analyzing their abundance, richness and the influence of pH, conductivity and water volume, on the populations. Sampling was done at Reserva Adolpho Ducke, Manaus, Amazonas, Brazil between 2003 and 2005. Six samplings were done in the rainy season and six in the dry season. On each sampling day, six terrestrial and six epiphytic bromeliads, totaling 144 sampling units, were retrieved. A total of 444 immature mosquitoes were collected, distributed in the following species: Culex (Microculex stonei Lane & Whitman, Culex (Microculex chryselatus Dyar & Knab, Culex (Microculex sp., Wyeomyia (Hystatomyia autocratica Dyar & Knab and Wyeomyia (Hystatomyia splendida Bonne-Wepster & Bonne. The relationship between abundance of Culicidae and sampling period was not significant, although abundance was higher in the dry period. There were significant correlations between water volume and the abundance (p = 0.003 and richness (p = 0.001 of culicids. The pH was positively related to the occurrence of the species Wy. autocratica (p= 0.010 and Wy. splendida (p= 0.006, demonstrating the influence of this factor in the structuring of bromeliad-inhabiting communities.

  18. Third Supplement to ’A Catalog of the Mosquitoes of the World’ (Diptera: Culicidae)

    Science.gov (United States)

    1992-11-01

    holotype 6: USNM). (Note 6). hancoi Geoffroy 1987:103 (65*). Type loc.: Banco forest, near Abijan. Ivory Coast (holotype 6: USNM). masoalensis...Diptera: Cul- Culev (Melanoconion) guedesi uma nova icidae) do Rio de Janeiro, Brasil . Mem. especie do Brasil (Diptera. Culicidae). Rev. ,0I Inst...Oswaldo Cruz Rio 78:501-505. Brasil . Biol. 51:193-196. Lourenco de Oliviera and L.M. Deane. 1984. McCabe. T.L. and L.M. Johnson. 1980. Cat- What is

  19. Human Blood Feeding Activity of Female Hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus(Diptera: Culicidae)

    OpenAIRE

    Yoshii, Manabu; Mine, Mariko; Kurokawa, Kenji; Oda, Tsutomu; Kato, Katsutomo; Ogawa, Yasunori; Eshita, Yuuki; Uchida, Keikichi

    2007-01-01

    Human blood feeding activity was examined in females of hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus during long photoperiod at 25℃. Blood feeding rates of hybrids were lower than in Culex pipiens quinquefasciatus and Culex pipiens pallens, and higher than in Culex pipiens pipiens, because no females fed on human blood in Culex pipiens pipiens.

  20. Comparative account of energy reserves in four co-occurring mosquito species in Kolkata, India (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Mohan Sushree

    2017-03-01

    Full Text Available Energy reserves in mosquitoes are an indicator of fitness, linking larval effort in resource acquisition with adult survival and fecundity. In other words, life history strategies and disease transmission potential can be related to the amount of energy reserves. The energy reserves of four mosquitoes – Aedes aegypti, Aedes albopictus, Armigeres subalbatus and Culex quinquefasciatus (Diptera: Culicidae – were calculated to justify species-specific differences in their life history strategies. Following repeated sampling of pupae from the respective larval habitats, the glycogen, sugar and lipid contents of individual mosquitoes were assessed and corroborated with pupal weight and adult wing length. Discriminant function analysis was used to acquire an initial reflection of the differences of the parameters among the sex and species of the mosquitoes considered in the study. Using logistic regression and ANOVA, the effects of species and sex as contributors to variations in energy reserves could be established. The results indicated that for all the mosquitoes, sex-specific differences were prominent with reference to the energy reserves. Species-specific differences in energy reserves reflect differences in resource acquisition and assimilation in the tissues, and thus the differences in the life history strategies of these four species.

  1. Anopheles (Anopheles) forattinii: a New Species in Series Arribalzagia (Diptera: Culicidae)

    Science.gov (United States)

    1999-05-01

    Anophelini, with notes on the malaria vectors (Diptera, Culicidae). Am. J. Hyg. Monogr. Ser. 18: l-20. 1948. Notas sobre a distribuicgo e a biologia dos...36: 282-300. Tadei, W. P., B. M. Mascarenhas, and M. G. Podesti. 1983. Biologia de anofelinos amazonicos. VIII. Conhecimentos sbbre a distribui@o...passa. 1988. Biologia de anofelinos amazonicos. XII. Ocorr&ncia de especies de Anopheles, din&mica da trans- missgo e controle da malaria na zona

  2. Potential Use of Pyriproxyfen for Control of Aedes aegypti Diptera: Culicidae) in Iquitos, Peru

    Science.gov (United States)

    2005-01-20

    ecdysteroid peak in the honey bee ( Apis mellifera ). Arthropod Struct. Dev. 29: 111Ð119. Received 16 January 2005; accepted 20 January 2005. 630 JOURNAL OF MEDICAL ENTOMOLOGY Vol. 42, no. 4 ...horizontal transfer Aedes aegypti (L.) (Diptera: Culicidae) is a perido- mestic mosquito species that exhibits a diurnal, bi- modal feeding pattern in...were col- lected in cups and returned to the large polystyrene/ gauze cages to emerge, mate, blood- feed , and con- tinue the rearing cycle. The colony was

  3. Estudo de Novos Atraentes de Oviposição de Fêmeas do Mosquito Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae)

    OpenAIRE

    Paulino, Sivaldo Soares

    2008-01-01

    Mosquito-borne viral tropical diseases represent a great threat to the global public health. Diseases transmitted by mosquitoes are usually endemic, and millions of people throughout the world are infected by mosquitoes of the Family Culicidae. The mosquito Aedes (Stegomyia) aegypti (Linnaeus, 1762) (Diptera: Culicidae) is the main vector of the dengue viruses and the urban yellow fever. The great proliferation of the different mosquitoes species is not only due to the high num...

  4. The J. Pedro Duret Mosquito Collection (Diptera: Culicidae)

    Science.gov (United States)

    1990-12-01

    the subgenus Mochlostyrox. Holotype male: ൙.I.60/ Colombia /Dep. Choco /Quibdo/Col. Duret/ [underside oflabel] 3354//HOLOTIPO/ /3354//Culex...1955/& Damasceno." Paratypes - none. chitIIe Duret, 1967b:113. Culex (Culex). Holotype male: "I.60/ Colombia /BogotajMonserrat/Col. Duret/[under- side of...Duret - Det. 1971." Paratypes - 4 males. ferreri Duret, 1968f:79. Culex (Melanoconion). Holotype male: ൞.III.61/ Colombia /N. Santander/Cucuta/Col. Duret

  5. Survey of the mosquitoes (Diptera: Culicidae) of Mayotte

    National Research Council Canada - National Science Library

    Le Goff, Gilbert; Goodman, Steven M; Elguero, Eric; Robert, Vincent

    2014-01-01

    A transversal survey of immature mosquitoes was conducted on Mayotte Island (France) in the Comoros Archipelago, western Indian Ocean, with the aim to inventory the Culicidae and to document inter-species relationships in different habitats...

  6. Behavioural and electrophysiological responses of the malaria mosquito Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) to human emanations

    NARCIS (Netherlands)

    Qiu, Y.T.; Smallegange, R.C.; Hoppe, S.; Loon, van J.J.A.; Bakker, E.J.; Takken, W.

    2004-01-01

    Behavioural and electrophysiological responses of Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) to human skin emanations collected on glass beads were studied using a dual-port olfactometer and electroantannography. Glass beads to which skin emanations from human hands had been

  7. Attractiveness of MM-X traps baited with human or synthetic odor to mosquitoes (Diptera: Culicidae) in The Gambia

    NARCIS (Netherlands)

    Qiu, Y.T.; Smallegange, R.C.; Braak, ter C.J.F.; Spitzen, J.; Loon, van J.J.A.; Jawara, M.; Milligan, P.; Galimard, A.M.S.; Beek, van T.A.; Knols, B.G.J.; Takken, W.

    2007-01-01

    Chemical cues play an important role in the host-seeking behavior of blood-feeding mosquitoes (Diptera: Culicidae). A field study was carried out in The Gambia to investigate the effects of human odor or synthetic odor blends on the attraction of mosquitoes. MM-X traps baited with 16 odor blends to

  8. Morphology and Evolution of the Larval Maxilla and Its Importance in the Classification of the Sabethini (Diptera: Culicidae)

    Science.gov (United States)

    1993-03-01

    where they lie ventral to the mandi- notypical subgenus of the genus Psorophora bles. For simplicity, the surface of each max- Robineau-Desvoidy. The...containing species with South Pacific (Diptera, Culicidae). Vols. I differently modified maxillae and maxillary and 2. University of California Press

  9. Nota sobre culicídeos (Diptera: Culicidae da bacia do rio Purus, Acre, Amazônia (Brasil

    Directory of Open Access Journals (Sweden)

    Delsio Natal

    1992-04-01

    Full Text Available Foram feitas coletas de mosquito (Diptera: Culicidae na área do projeto de Colonização Pedro Peixoto, no Estado do Acre, Brasil. Obteve-se um total de 4.588 exemplares pertencentes a 53 espécies ou grupos. Salienta-se a ocorrência de Anopheles (Nyssorhynchus oswaldoi.

  10. A comparative analysis of resistance testing methods in Aedes albopictus (Diptera: Culicidae) from St. Johns County, Florida

    Science.gov (United States)

    Aedes albopictus Skuse (Diptera: Culicidae) was tested for resistance to permethrin, bifenthrin, and malathion using Centers for Disease Control and Prevention (CDC) bottle bioassays and topical toxicology assays on adults and larval bioassays. Eggs were collected from 3 locations across St. Johns C...

  11. [Mosquito fauna (Diptera:Culicidae) from Falcon State, Venezuela. I. New records and current checklist].

    Science.gov (United States)

    Navarro, J C; Bastidas, R J; Zavala, Y

    1994-01-01

    A total of 16 new species records of Culicidae from Falcon State was collected at the "Juan Crisostomo Falcon National Park" (Sierra de San Luis), Natural Monument "Cerro Santa Ana", Coro, and La Vela. Species of Sabethini, Culicini and Toxorhynchitini Tribes were found in natural breeding sites (Phytotelmata), with special occurrence in plants belonging to Tillandsia, Vriesea, Guzmania, Aechmea (Bromelianceae), Heliconia (Heliconiaceae), Calathea (Marantaceae) and Colocasia (Araceae). Aedini and Mansonini were collected only as adults. A specie of Culex (Carrollia) was collected from an artificial container. The Culicidae species belong to 6 genera out of the 23 genera reported from Venezuela (Culex, Wyeomyia, Johnbelkinia, Aedes, Psorophora, Mansonia and Coquillettidia) and to 5 Tribes out of the 9 present in the country. The Aedini, Sabethini and Culicini Tribes were richer in species with 5, 4 and 4 species, respectively, than the Mansonini (2 species) and Toxorhynchitini (1 species) Tribes. We discuss some bioecological aspects regarding the 16 new-species records in Falcon State and give a checklist of the mosquito species previously reported in the literature.

  12. New Records of Mosquitoes (Diptera: Culicidae) from Bolívar State in South Eastern Venezuela, with 27 New Species for the State and 5 of Them New in the Country

    Science.gov (United States)

    Berti, Jesús; Guzmán, Hernán; Estrada, Yarys; Ramírez, Rodrigo

    2015-01-01

    This is the first part of a series of studies related to mosquito ecological and biogeographic aspects. A total of 69 mosquito species (Diptera: Culicidae) was collected in 16 localities sampled in the Gran Sabana Municipality, Canaima National Park, and Venezuela. Twenty-seven mosquito species are recorded for the first time from Bolívar State, Venezuela. Five of them species are reported for the first time in Venezuela: Anopheles malefactor Dyar and Knab (1907); Chagasia bonneae Root (1927); Chagasia ablusa Harbach (2009); Culex anduzei Lane (1944), and Uranotaenia leucoptera Theobald (1907). Their medical importance is commented, and ecological and epidemiological aspects are discussed. A checklist of the mosquito species reported in the Gran Sabana County is given. PMID:25853113

  13. Landscape structure affects distribution of potential disease vectors (Diptera: Culicidae)

    OpenAIRE

    Zittra, Carina; Vitecek, Simon; Obwaller, Adelheid G.; Rossiter, Heidemarie; Eigner, Barbara; Zechmeister, Thomas; Waringer, Johann; Fuehrer, Hans-Peter

    2017-01-01

    Background Vector-pathogen dynamics are controlled by fluctuations of potential vector communities, such as the Culicidae. Assessment of mosquito community diversity and, in particular, identification of environmental parameters shaping these communities is therefore of key importance for the design of adequate surveillance approaches. In this study, we assess effects of climatic parameters and habitat structure on mosquito communities in eastern Austria to deliver these highly relevant basel...

  14. Identification of Species Related to Anopheles (Nyssorhynchus) albitarsis by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (Diptera: Culicidae)

    Science.gov (United States)

    1995-11-01

    plified polymorphic DNA in the population genet- ics and systematics of grasshoppers . Genome 35: 569-574. Galvgo ALA, Damesceno RG 1942. Sobre urn...iynchus) albitarsis by Random Amplified Polymorphic DNA -Polymerase Chain Reaction (Diptera: Culicidae) Richard C Wilkerson/+, Thomas V Caffigan, Jo...Instituto de Biologia do ExCrcito, Rua Francisco Manuel 102, 2091 l-270 Rio de Janeiro, RJ, Brasil Species-specific Random Amplified Polymorphic DNA

  15. [Detection of flavivirus in mosquitoes (Diptera: Culicidae) from Easter Island-Chile].

    Science.gov (United States)

    Collao, Ximena; Prado, Lorena; González, Christian; Vásquez, Ana; Araki, Romina; Henríquez, Tuki; Peña, Cindy M

    2015-02-01

    Flaviviruses are arthropod-borne viruses, mainly by mosquitoes of the genera Aedes and Culex (Culicidae) that are detected in tropical and subtropical areas. Main flaviviruses of public health importance are: dengue, West Nile virus, yellow fever, among others. In continental Chile, flaviviruses has not been detected. However, there are indigenous cases of dengue detected in Easter Island since 2002, as the presence of its vector Aedes aegypti. The aim of this study was: To determine diversity of flavivirus mosquitoes present in Easter Island. Thirty pools of mosquitoes collected in Hanga Roa were analyzed; a RT-PCR nested flavivirus was performed. Thirteen positive samples were detected and the amplification products were sequenced, identifying two specific flavivirus Insect, the Cell fusing agent virus and other related viruses Kamiti River. This is the first study in Chile showed the presence of flavivirus in vectors in Easter Island.

  16. SITUACIÓN ACTUAL EN ESPAÑA Y ECO-EPIDEMIOLOGÍA DE LAS ARBOVIROSIS TRANSMITIDAS POR MOSQUITOS CULÍCIDOS (DIPTERA: CULICIDAE

    Directory of Open Access Journals (Sweden)

    Rubén Bueno Marí

    2010-01-01

    Full Text Available En el presente manuscrito se analiza la posible emergencia y/o reemergencia en España de algunas de las arbovirosis transmitidas por mosquitos culícidos (Diptera: Culicidae de mayor incidencia a nivel mundial en los últimos años. Los datos faunísticos, bioecológicos y de distribución de los culícidos en nuestro país permiten discernir entre especies con capacidad de mantener la enzootia de algunas de estas arbovirosis de otras que pueden actuar como vectores puente de la virosis hasta el ser humano. Los resultados revelan la existencia de especies, algunas de ellas muy frecuentes en los humedales de nuestro país y fuertemente antropófilas como Aedes vexans, Culex modestus, Culex pipiens u Ochlerotatus caspius, con una elevada capacidad para transmitir flavivirus como el virus West Nile o el virus Usutu. Además, la reciente introducción, establecimiento y expansión del mosquito tigre, Aedes albopictus, abre una preocupante vía para la aparición de posibles brotes, probablemente incluso de tipo epidémico, de arbovirosis habitualmente importadas a nuestro país por personas inmigrantes y turistas, como el Dengue o Chikungunya. Por último, también se discute el interés epidemiológico de especies propias de nuestro entorno como Aedes vittatus u Ochlerotatus geniculatus, debido a su capacidad vectorial constatada para la transmisión de algunas de estas virosis típicamente tropicales.

  17. Host feeding patterns of Connecticut mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Magnarelli, L A

    1977-05-01

    Blood-engorged Coquillettidia perturbans, Psorophora ferox, Culex, Culiseta, and Aedes mosquitoes were collected principally by sweep net from salt marsh and woodland habitats in Connecticut. Of the 570 mosquitoes tested, precipitin tests identified the origins of 517 blood meals and revealed distinct host feeding patterns. Aedes mosquitoes fed chiefly on mammals; A. abserratus, A. cantator, and A. vexans showed selectivity for cattle and (or) horses. A. cantator also obtained blood from avian hosts and, in some instances, showed mixed passerine-mammal blood meals. These findings increase the vector potential of this salt marsh mosquito for eastern equine encephalomyelitis virus. Feedings on deer by A. abserratus suggest potential involvement of this mosquito in the transmission of certain subtypes of California encephalitis. Culex-pipiens, C. restuans, Culiseta melanura, and Cs. morsitans dyari acquired blood almost exclusively from passeriform birds.

  18. National Mosquito (Diptera: Culicidae) Survey in The Netherlands 2010-2013.

    Science.gov (United States)

    Ibañez-Justicia, A; Stroo, A; Dik, M; Beeuwkes, J; Scholte, E J

    2015-03-01

    From 2010 onwards, a nationwide mosquito monitoring scheme has been conducted in The Netherlands with the aim of gaining crucial information about mosquito (Diptera: Culicidae) species composition, geographical distributions, biodiversity, and habitat preferences. The results of this study are based on 778 randomly sampled mosquito locations. These are divided into three main habitat types: urban, rural-agricultural, and natural areas. Twenty-seven mosquito species were found: 26 indigenous and 1 exotic, Aedes japonicus japonicus (Theobald, 1901). The preliminary results are presented here, with details of their species distribution and seasonality. Monitoring the temporal and spatial distribution of mosquitoes is an essential step in the risk analysis of emerging mosquito-borne diseases. © The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Landscape structure affects distribution of potential disease vectors (Diptera: Culicidae).

    Science.gov (United States)

    Zittra, Carina; Vitecek, Simon; Obwaller, Adelheid G; Rossiter, Heidemarie; Eigner, Barbara; Zechmeister, Thomas; Waringer, Johann; Fuehrer, Hans-Peter

    2017-04-26

    Vector-pathogen dynamics are controlled by fluctuations of potential vector communities, such as the Culicidae. Assessment of mosquito community diversity and, in particular, identification of environmental parameters shaping these communities is therefore of key importance for the design of adequate surveillance approaches. In this study, we assess effects of climatic parameters and habitat structure on mosquito communities in eastern Austria to deliver these highly relevant baseline data. Female mosquitoes were sampled twice a month from April to October 2014 and 2015 at 35 permanent and 23 non-permanent trapping sites using carbon dioxide-baited traps. Differences in spatial and seasonal abundance patterns of Culicidae taxa were identified using likelihood ratio tests; possible effects of environmental parameters on seasonal and spatial mosquito distribution were analysed using multivariate statistical methods. We assessed community responses to environmental parameters based on 14-day-average values that affect ontogenesis. Altogether 29,734 female mosquitoes were collected, and 21 of 42 native as well as two of four non-native mosquito species were reconfirmed in eastern Austria. Statistical analyses revealed significant differences in mosquito abundance between sampling years and provinces. Incidence and abundance patterns were found to be linked to 14-day mean sunshine duration, humidity, water-level maxima and the amount of precipitation. However, land cover classes were found to be the most important factor, effectively assigning both indigenous and non-native mosquito species to various communities, which responded differentially to environmental variables. These findings thus underline the significance of non-climatic variables for future mosquito prediction models and the necessity to consider these in mosquito surveillance programmes.

  20. Updated checklist of the mosquitoes (Diptera: Culicidae) of Belgium.

    Science.gov (United States)

    Boukraa, Slimane; Dekoninck, Wouter; Versteirt, Veerle; Schaffner, Francis; Coosemans, Marc; Haubruge, Eric; Francis, Frederic

    2015-12-01

    Most information about the systematics and bioecology of Belgian mosquitoes dates back from before 1950, and only scattered information was produced during the last decades. In this paper we review and update the list of mosquito species recorded in Belgium, from first report (1908) to 2015. Six genera and 31 species were recorded so far, including 28 autochthonous species and three invasive alien species recently recorded in Belgium: Aedes albopictus (Skuse 1894), Ae. japonicus japonicus (Theobald 1901), and Ae. koreicus (Edwards 1917). The six genera are Anopheles (five species), Aedes (sixteen species), Coquillettidia (one species), Culex (four species), Culiseta (four species), and Orthopodomyia (one species). © 2015 The Society for Vector Ecology.

  1. Lista dos mosquitos da Bolívia: (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    N. L. Cerqueira

    1943-08-01

    Full Text Available Em quinze gêneros, cento e vinte e seis espécies de mosquitos foram constatadas no material capturado pelo Servicio de Fiebre Amarilla desde 1933 até 1942. Êste número, três vezes mais elevado do que o existente na literatura para o país, seria ainda maior se possível fôsse identificar sem o auxílio de machos inúmeras fêmeas das espécies de Culex. Tôdas as espécies estudadas apresentavam suas distribuições geográficas nos departamentos e províncias onde casos de Febre Amarela foram observados. Algumas cosiderações foram feitas em torno de espécies que não correspondiam exatamente com as descrições existentes, assim como descrições de outras foram dadas, cujos sexos opostos apenas eram conhecidos.One hundred and twenty-six species of mosquitoes, corresponding fifteen genera, have been found in material collected by the Bolivian Yellow Fever Service between 1933 and 1942. This number is three times that given for the country in existing literature and would be even largar if it were possible to identify a consierable group of Culex mosquitoes composed principally of female specimens. All species studied come from Departmetns and Provinces where cases of yellow fever have been found. Consideration has been given to certain species which do not agree exactly with existing descriptions, and supplementary descriptions have been made for the male or female of two additional species for which only description of the opposite sex had existed.

  2. Tackling the growing threat of dengue: Phyllanthus niruri-mediated synthesis of silver nanoparticles and their mosquitocidal properties against the dengue vector Aedes aegypti (Diptera: Culicidae)

    Science.gov (United States)

    Mosquitoes transmit pathogens that cause millions of human deaths each year. Dengue virus is transmitted to humans in tropical and subtropical areas by Aedes aegypti (Diptera: Culicidae). The use of synthetic insecticides to control this mosquito is accompanied by high operational costs and adverse...

  3. Survey of the mosquitoes (Diptera: Culicidae) of Mayotte.

    Science.gov (United States)

    Le Goff, Gilbert; Goodman, Steven M; Elguero, Eric; Robert, Vincent

    2014-01-01

    A transversal survey of immature mosquitoes was conducted on Mayotte Island (France) in the Comoros Archipelago, western Indian Ocean, with the aim to inventory the Culicidae and to document inter-species relationships in different habitats. In total 420 habitats were sampled for larvae and/or pupae mosquitoes, resulting in more than 6,000 specimens. Forty species belonging to 15 genera were collected, with eight taxa integrated for the first time to the Mayotte mosquito list. The most frequently recorded species were Stegomyia aegypti, St. albopicta, Anopheles gambiae and Eretmapodites subsimplicipes, the first three species being known vectors of viruses and parasites transmitted to humans. Mean species richness in habitats ranged from 1.00 to 3.29, with notable differences between habitats. For example, water-filled axils of banana leaves, tree-holes and crab-holes had low species richness, while cut bamboo, water pools, abandoned tires and marsh and swamp water had notably higher species richness. Twenty-seven mosquito species belonging to 12 genera were routinely collected (in ≥20% of at least one type of larval habitat) suggesting that multiple species play a role in the biocenosis of these aquatic habitats. Multispecies association was observed in 52% of the habitats. The co-occurrence of up to six species belonging to five genera was recorded in a single habitat. The mosquitoes of Mayotte show notable biogeographical affinities to those of Madagascar, as compared to the African continent. These two potential source areas are nearly equidistant from Mayotte, which in turn indicates biased dispersal from east to west. Our findings suggest that with relatively short-term intensive sampling in different habitats, it is possible to approach exhaustive species inventories based on collection of larvae. Mayotte, with its modest elevation range and land surface, has a notable species richness of mosquitoes with 45 well-documented species belonging to 15 genera.

  4. Nationwide inventory of mosquito biodiversity (Diptera: Culicidae) in Belgium, Europe.

    Science.gov (United States)

    Versteirt, V; Boyer, S; Damiens, D; De Clercq, E M; Dekoninck, W; Ducheyne, E; Grootaert, P; Garros, C; Hance, T; Hendrickx, G; Coosemans, M; Van Bortel, W

    2013-04-01

    To advance our restricted knowledge on mosquito biodiversity and distribution in Belgium, a national inventory started in 2007 (MODIRISK) based on a random selection of 936 collection points in three main environmental types: urban, rural and natural areas. Additionally, 64 sites were selected because of the risk of importing a vector or pathogen in these sites. Each site was sampled once between May and October 2007 and once in 2008 using Mosquito Magnet Liberty Plus traps. Diversity in pre-defined habitat types was calculated using three indices. The association between species and environmental types was assessed using a correspondence analysis. Twenty-three mosquito species belonging to traditionally recognized genera were found, including 21 indigenous and two exotic species. Highest species diversity (Simpson 0.765) and species richness (20 species) was observed in natural areas, although urban sites scored also well (Simpson 0.476, 16 species). Four clusters could be distinguished based on the correspondence analysis. The first one is related to human modified landscapes (such as urban, rural and industrial sites). A second is composed of species not associated with a specific habitat type, including the now widely distributed Anopheles plumbeus. A third group includes species commonly found in restored natural or bird migration areas, and a fourth cluster is composed of forest species. Outcomes of this study demonstrate the effectiveness of the designed sampling scheme and support the choice of the trap type. Obtained results of this first country-wide inventory of the Culicidae in Belgium may serve as a basis for risk assessment of emerging mosquito-borne diseases.

  5. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar.

    Science.gov (United States)

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar. © M.L. Tantely et al., published by EDP Sciences, 2016.

  6. An updated checklist of mosquito species (Diptera: Culicidae from Madagascar

    Directory of Open Access Journals (Sweden)

    Tantely Michaël Luciano

    2016-01-01

    Full Text Available An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species. This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species, Aedes (35 species, Anopheles (26 species, Coquillettidia (3 species, Culex (at least 50 species, Eretmapodites (4 species, Ficalbia (2 species, Hodgesia (at least one species, Lutzia (one species, Mansonia (2 species, Mimomyia (22 species, Orthopodomyia (8 species, Toxorhynchites (6 species, and Uranotaenia (73 species. Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%. Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27% with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar.

  7. An updated checklist of mosquito species (Diptera: Culicidae) from Madagascar

    Science.gov (United States)

    Tantely, Michaël Luciano; Le Goff, Gilbert; Boyer, Sébastien; Fontenille, Didier

    2016-01-01

    An updated checklist of 235 mosquito species from Madagascar is presented. The number of species has increased considerably compared to previous checklists, particularly the last published in 2003 (178 species). This annotated checklist provides concise information on endemism, taxonomic position, developmental stages, larval habitats, distribution, behavior, and vector-borne diseases potentially transmitted. The 235 species belong to 14 genera: Aedeomyia (3 species), Aedes (35 species), Anopheles (26 species), Coquillettidia (3 species), Culex (at least 50 species), Eretmapodites (4 species), Ficalbia (2 species), Hodgesia (at least one species), Lutzia (one species), Mansonia (2 species), Mimomyia (22 species), Orthopodomyia (8 species), Toxorhynchites (6 species), and Uranotaenia (73 species). Due to non-deciphered species complexes, several species remain undescribed. The main remarkable characteristic of Malagasy mosquito fauna is the high biodiversity with 138 endemic species (59%). Presence and abundance of species, and their association, in a given location could be a bio-indicator of environmental particularities such as urban, rural, forested, deforested, and mountainous habitats. Finally, taking into account that Malagasy culicidian fauna includes 64 species (27%) with a known medical or veterinary interest in the world, knowledge of their biology and host preference summarized in this paper improves understanding of their involvement in pathogen transmission in Madagascar. PMID:27101839

  8. Larvicidal efficacy of different plant parts of railway creeper, Ipomoea cairica Extract Against Dengue Vector Mosquitoes, Aedes albopictus (Diptera: Culicidae) and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    AhbiRami, Rattanam; Zuharah, Wan Fatma; Thiagaletchumi, Maniam; Subramaniam, Sreeramanan; Sundarasekar, Jeevandran

    2014-01-01

    Natural insecticides from plant origin against mosquito vectors have been the main concern for research due to their high level of eco-safety. Control of mosquitoes in their larval stages are an ideal method since Aedes larvae are aquatic, thus it is easier to deal with them in this habitat. The present study was specifically conducted to explore the larvicidal efficacy of different plant parts of Ipomoea cairica (L.) or railway creeper crude extract obtained using two different solvents; methanol and acetone against late third-stage larvae of Aedes albopictus (Skuse) and Aedes aegypti (L.) (Diptera: Culicidae). Plant materials of I. cairica leaf, flower, and stem were segregated, airdried, powdered, and extracted using Soxhlet apparatus. Larvicidal bioassays were performed by using World Health Organization standard larval susceptibility test method for each species which were conducted separately for different concentration ranging from 10 to 450 ppm. Both acetone and methanol extracts showed 100% mortality at highest concentration tested (450 ppm) after 24 h of exposure. Results from factorial ANOVA indicated that there were significant differences in larvicidal effects between mosquito species, solvent used and plant parts (F=5.71, df=2, Palbopictus with LC50 of 105.59 ppm compared with other fractions of I. cairica extract obtained from flower, stem, and when methanol are used as solvent. The larvae of Ae. aegypti appeared to be more susceptible to I. cairica extract with lower LC50 value compared with Ae. albopictus (F=8.83, df=1, PAedes mosquitoes. This study quantified the larvicidal property of I. cairica extract, providing information on lethal concentration that may have potential for a more eco-friendly Aedes mosquito control program. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  9. Leaf extracts of Melia azedarach Linnaeus (Sapindales: Meliaceae) act as larvicide against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae).

    Science.gov (United States)

    Prophiro, Josiane Somariva; Rossi, Juliana Chedid Nogared; Pedroso, Murilo Fernandes; Kanis, Luiz Alberto; Silva, Onilda Santos

    2008-01-01

    The objective of this study was to compare the larvicidal effect of hydroethanolic extracts of fresh and dry leaves of Melia azedarach Linnaeus (Sapindales: Meliaceae) on Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae). All the extracts evaluated induced mortality among the third and fourth instar larvae of Aedes aegypti after 24 and 48 hours of exposure to the products. Although previous studies had demonstrated the action of seeds and fruits of Melia azedarach against the larvae of different Aedes aegypti populations, the present report is the first to show the larvicidal effect of the fresh and dry leaves of this plant.

  10. Analyzing mosquito (Diptera: culicidae diversity in Pakistan by DNA barcoding.

    Directory of Open Access Journals (Sweden)

    Muhammad Ashfaq

    Full Text Available BACKGROUND: Although they are important disease vectors mosquito biodiversity in Pakistan is poorly known. Recent epidemics of dengue fever have revealed the need for more detailed understanding of the diversity and distributions of mosquito species in this region. DNA barcoding improves the accuracy of mosquito inventories because morphological differences between many species are subtle, leading to misidentifications. METHODOLOGY/PRINCIPAL FINDINGS: Sequence variation in the barcode region of the mitochondrial COI gene was used to identify mosquito species, reveal genetic diversity, and map the distribution of the dengue-vector species in Pakistan. Analysis of 1684 mosquitoes from 491 sites in Punjab and Khyber Pakhtunkhwa during 2010-2013 revealed 32 species with the assemblage dominated by Culex quinquefasciatus (61% of the collection. The genus Aedes (Stegomyia comprised 15% of the specimens, and was represented by six taxa with the two dengue vector species, Ae. albopictus and Ae. aegypti, dominant and broadly distributed. Anopheles made up another 6% of the catch with An. subpictus dominating. Barcode sequence divergence in conspecific specimens ranged from 0-2.4%, while congeneric species showed from 2.3-17.8% divergence. A global haplotype analysis of disease-vectors showed the presence of multiple haplotypes, although a single haplotype of each dengue-vector species was dominant in most countries. Geographic distribution of Ae. aegypti and Ae. albopictus showed the later species was dominant and found in both rural and urban environments. CONCLUSIONS: As the first DNA-based analysis of mosquitoes in Pakistan, this study has begun the construction of a barcode reference library for the mosquitoes of this region. Levels of genetic diversity varied among species. Because of its capacity to differentiate species, even those with subtle morphological differences, DNA barcoding aids accurate tracking of vector populations.

  11. Leaf extracts of Melia azedarach Linnaeus (Sapindales: Meliaceae act as larvicide against Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae Extratos de folhas de Melia azedarach Linnaeus (Sapindales: Meliaceae atuam como larvicida de Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Josiane Somariva Prophiro

    2008-12-01

    Full Text Available The objective of this study was to compare the larvicidal effect of hydroethanolic extracts of fresh and dry leaves of Melia azedarach Linnaeus (Sapindales: Meliaceae on Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae. All the extracts evaluated induced mortality among the third and fourth instar larvae of Aedes aegypti after 24 and 48 hours of exposure to the products. Although previous studies had demonstrated the action of seeds and fruits of Melia azedarach against the larvae of different Aedes aegypti populations, the present report is the first to show the larvicidal effect of the fresh and dry leaves of this plant.O objetivo deste trabalho foi comparar o efeito larvicida de extratos hidro-etanólicos de folhas verdes e secas de Melia azedarach Linnaeus (Sapindales: Meliaceae em Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae. Todos os extratos avaliados induziram mortalidade em larvas de 3º e 4º estágios de Aedes aegypti, após 24 e 48 horas de exposição aos produtos. Embora estudos prévios tenham demonstrado a ação de sementes e frutos de Melia azedarach em larvas de diferentes populações de Aedes aegypti, o presente estudo é o primeiro a reportar o efeito larvicida de folhas verdes e secas desta planta.

  12. Near-infrared spectroscopy and microstructure of the scales of Sabethes ( Sabethes albiprivus (Diptera: Culicidae

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    Betina Westphal-Ferreira

    Full Text Available ABSTRACT Near-infrared spectroscopy and microstructure of the scales of Sabethes (Sabethes albiprivus (Diptera: Culicidae. Sabethes (Sabethes albiprivus Theobald individuals vary considerably in size and color of the reflections of the scales on their thorax, abdomen, antepronotal lobes and occiput. The goal of this study was to investigate and to characterize the differences in the color of the scales among preserved specimens and to analyze the differences in the microstructures of the scales that cover their bodies using near-infrared spectroscopy, and to evaluate whether the latter is efficient in distinguishing the populations. A total of 201 adult females were analyzed for the characterization of color patterns. In addition, absorbance spectra and scanning electron microscope images were obtained from them. As a result of color analysis, two variations were identified, one represented by specimens with yellow or green scales and the other with blue or purple scales. The same two variations were corroborated using NIRS. Analysis of the microstructure of the scales lining the mesonotum, occiput and antepronotal lobes resulted in the same variations. The three methodologies, near-infrared spectroscopy, scanning electron microscopy and coloration of the reflections of the scales revealed two variations within Sa. albiprivus.

  13. Does autocthonous primary production influence oviposition by Aedes japonicus japonicus (Diptera: Culicidae) in container habitats?

    Science.gov (United States)

    Lorenz, Amanda R; Walker, Edward D; Kaufman, Michael G

    2013-01-01

    Aedes (Finlaya) japonicus japonicus (Theobald) (Diptera: Culicidae) is recently invasive in North America and has expanded its range rapidly since 1998. Throughout its native and expanded range, Ae. j. japonicus larvae are commonly observed in many types of natural and artificial water-filled containers that vary in organic matter content and exposure to sunlight. Larvae are most often found in containers with decaying leaf material or algae, and we postulated that the added autocthonous primary production from algae could be both an important food source for larvae and an influential oviposition attractant to adult Ae. j. japonicus. We tested this hypothesis by placing plastic containers with varied levels of shading to manipulate algal density in the field, and then monitored oviposition by natural populations of Ae. j. japonicus. Over 99% of larvae hatching from eggs laid on the walls of our containers were Ae. j. japonicus, indicating that this species is a dominant colonizer of artificial containers in the study areas. Although full shading treatments effectively reduced algal biomass (significant reduction in chlorophyll a levels), at only one of three sites did this appear to affect Ae. j. japonicus oviposition. We conclude that algae in larval habitats are not a major factor in oviposition choices of adult Ae. j. japonicus females except when in situ primary production is high enough to substantially alter overall organic matter content cues.

  14. Worthy of their name: how floods drive outbreaks of two major floodwater mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Berec, Ludĕk; Gelbic, Ivan; Sebesta, Oldrich

    2014-01-01

    An understanding of how climate variables drive seasonal dynamics of mosquito populations is critical to mitigating negative impacts of potential outbreaks, including both nuisance effects and risk of mosquito-borne infectious disease. Here, we identify climate variables most affecting seasonal dynamics of two major floodwater mosquitoes, Aedes vexans (Meigen, 1830) and Aedes sticticus (Meigen, 1838) (Diptera: Culicidae), along the lower courses of the Dyje River, at the border between the Czech Republic and Austria. Monthly trap counts of both floodwater mosquitoes varied both across sites and years. Despite this variability, both models used to fit the observed data at all sites (and especially that for Ae. sticticus) and site-specific models fitted the observed data quite well. The most important climate variables we identified-temperature and especially flooding-were driving seasonal dynamics of both Aedes species. We suggest that flooding determines seasonal peaks in the monthly mosquito trap counts while temperature modulates seasonality in these counts. Hence, floodwater mosquitoes indeed appear worthy of their name. Moreover, the climate variables we considered for modeling were able reasonably to predict mosquito trap counts in the month ahead. Our study can help in planning flood management; timely notification of people, given that these mosquitoes are a real nuisance in this region; public health policy management to mitigate risk from such mosquito-borne diseases as that caused in humans by the Tahyna virus; and anticipating negative consequences of climate change, which are expected only to worsen unless floods, or the mosquitoes themselves, are satisfactorily managed.

  15. Sexual chemoecology of mosquitoes (Diptera, Culicidae): Current knowledge and implications for vector control programs.

    Science.gov (United States)

    Vaníčková, Lucie; Canale, Angelo; Benelli, Giovanni

    2017-04-01

    Mosquitoes (Diptera: Culicidae) act as vectors of medical and veterinary importance, due to their ability to transmit many pathogens and parasites. Renewed interest has been recently devoted to the potential of sterile insect technique (SIT) for mosquito suppression. However, the success of the SIT is mostly dependent on the ability of sterile males to compete for mates with the wild ones in the field. Nevertheless, little is known on the sexual chemical ecology of mosquitoes, with special reference to the role of chemical signals in males. We reviewed the current knowledge on mosquito sexual chemical ecology and other key cues affecting courtship and mating behavior. The information available on the aggregation and sex pheromones in mosquito males is rather limited. To the best of our knowledge, the components of the aggregation pheromone stimulating swarming mechanisms have been fully characterized only for Aedes aegypti, while evidence for aggregation pheromones in other mosquito species remains elusive. Further research on this issue is needed, as well as to dissect the relative importance of visual (with special reference to swarming landmarks), vibrational, olfactory and tactile cues perceived during swarming and mate. On the other hand, more knowledge is available for cuticular hydrocarbons, which modulate mating behavior in several species of economic importance. These compounds, coupled with volatile aggregation components, have potential interest for the development of monitoring and trapping systems. In addition, the analyses of cuticular hydrocarbons are essential for discrimination between closely related mosquito species and/or populations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Species Composition and Distribution of Adult Anopheles (Diptera: Culicidae) in Panama

    Science.gov (United States)

    LOAIZA, J. R.; BERMINGHAM, E.; SCOTT, M. E.; ROVIRA, J. R.; CONN, J. E.

    2010-01-01

    Anopheles (Diptera: Culicidae) species composition and distribution were studied using human landing catch data over a 35-yr period in Panama. Mosquitoes were collected from 77 sites during 228 field trips carried out by members of the National Malaria Eradication Service. Fourteen Anopheles species were identified. The highest average human biting rates were recorded from Anopheles (Nyssorhynchus) albimanus (Wiedemann) (9.8 bites/person/night) and Anopheles (Anopheles) punctimacula (Dyar and Knab) (6.2 bites/person/night). These two species were also the most common, present in 99.1 and 74.9%, respectively, of the sites. Anopheles (Nyssorhynchus) aquasalis (Curry) was encountered mostly in the indigenous Kuna Yala Comarca along the eastern Atlantic coast, where malaria case history and average human biting rate (9.3 bites/person/night) suggest a local role in malaria transmission. An. albimanus, An. punctimacula, and Anopheles (Anopheles) vestitipennis (Dyar and Knab) were more abundant during the rainy season (May–December), whereas An. aquasalis was more abundant in the dry season (January–April). Other vector species collected in this study were Anopheles (Kerteszia) neivai (Howard, Dyar, and Knab) and Anopheles (Anopheles) pseudopunctipennis s.l. (Theobald). High diversity of Anopheles species and six confirmed malaria vectors in endemic areas of Panama emphasize the need for more detailed studies to better understand malaria transmission dynamics. PMID:18826025

  17. Screening of Asteraceae (Compositae Plant Extracts for Larvicidal Activity against Aedes fluviatilis (Diptera: Culicidae

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    Maria E Macêdo

    1997-07-01

    Full Text Available Ethanol extracts of 83 plants species belonging to the Asteraceae (Compositae family, collected in the State of Minas Gerais, Brazil, were tested for larvicidal activity against the mosquito Aedes fluviatilis - Diptera: Culicidae. The extract from Tagetes minuta was the most active with a LC90 of 1.5 mg/l and LC50 of 1.0 mg/l. This plant has been the object of several studies by other groups and its active components have already been identified as thiophene derivatives, a class of compounds present in many Asteraceae species. The extract of Eclipta paniculata was also significantly active, with a LC90 of 17.2 mg/l and LC50 of 3.3 mg/l and no previous studies on its larvicidal activity or chemical composition could be found in the literature. Extracts of Achryrocline satureoides, Gnaphalium spicatum, Senecio brasiliensis, Trixis vauthieri, Tagetes patula and Vernonia ammophila were less active, killing more than 50% of the larvae only at the higher dose tested (100 mg/l.

  18. Comparative studies on effects of three chitin synthesis inhibitors on common malaria mosquito (Diptera: Culicidae).

    Science.gov (United States)

    Zhu, Kun Yan; Heise, Stephanie; Zhang, Jianzhen; Anderson, Troy D; Starkey, Sharon R

    2007-11-01

    Toxicities of three chitin synthesis inhibitors (diflubenzuron, nikkomycin Z and polyoxin D) were evaluated using second instars of the common malaria mosquito, Anopheles quadrimaculatus Say (Diptera: Culicidae). Neither nikkomycin Z nor polyoxin D at 50 microg/liter caused significant larval mortality, although they reduced the body weight of the survivors by 20.5 and 33.8%, respectively, in 48 h. In contrast, exposures of the larvae to diflubenzuron at 12.5 microg/liter for 48 h resulted in 86.7% larval mortality and reduced the body weight of the survivors by 29.1%. Exposure of the pupae (affect chitin contents in the guts. Our results indicated that diflubenzuron was highly toxic to second instars by not only causing high larval mortality but also by affecting their growth. Diflubenzuron was also fairly toxic to pupae by not only causing pupal mortality but also affecting the adult emergence. Our results suggest that diflubenzuron might affect only chitin synthesis in the cuticle but not in the peritrophic matrix, which is probably due to diflubenzuron's direct contact to mosquito larvae in water, slow distribution in insect body, rapid degradation in the insect gut, or a combination.

  19. Aedes aegypti survival in the presence of Toxorhynchites violaceus (Diptera: Culicidae fourth instar larvae

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    Daniel S Albeny

    2011-08-01

    Full Text Available The mosquito Aedes aegypti (Linnaeus, 1762 is the main vector of dengue and yellow fever viruses. Different methods have been used to control A. aegypti, including chemical and biological tools. However, chemical control can lead to a subsequent increase in the mosquitoes' insecticide resistance, and biological control represents an important method as an alternative to insecticide usage. Larvae from the Toxorhynchites genus (Diptera: Culicidae are predators of other mosquitoes and represent a potential natural biocontrol agent of A. aegypti larvae. In the present work, A. aegypti larval survival was studied in the presence of the neotropical Toxorhynchites violaceus (Wiedemann, 1821 fourth instar larvae. Toxorhynchites violaceus consumption of A. aegypti increased during the 192 hours of the experiment and was more marked in the intervals between 96 and 120 hours and between 168 and 192 hours, when the A. aegypti survival reached 0%. During the fourth instar, T. violaceus increased its predation on A. aegypti larvae, possibly in order to increase its nutrient storage prior to pupation. Otherwise, low prey consumption can lead to a nutritional deficit for the larvae, delaying the adult's sexual development and reducing its egg production. Here we show that A. aegypti survival can be reduced by the T. violaceus fourth larvae predation under laboratory conditions

  20. Impact of livestock on a mosquito community (Diptera: Culicidae) in a Brazilian tropical dry forest.

    Science.gov (United States)

    Santos, Cleandson Ferreira; Borges, Magno

    2015-01-01

    This study evaluated the effects of cattle removal on the Culicidae mosquito community structure in a tropical dry forest in Brazil. Culicidae were collected during dry and wet seasons in cattle presence and absence between August 2008 and October 2010 and assessed using multivariate statistical models. Cattle removal did not significantly alter Culicidae species richness and abundance. However, alterations were noted in Culicidae community composition. This is the first study to evaluate the impact of cattle removal on Culicidae community structure in Brazil and demonstrates the importance of assessing ecological parameters such as community species composition.

  1. Impact of livestock on a mosquito community (Diptera: Culicidae in a Brazilian tropical dry forest

    Directory of Open Access Journals (Sweden)

    Cleandson Ferreira Santos

    2015-08-01

    Full Text Available AbstractINTRODUCTION: This study evaluated the effects of cattle removal on the Culicidae mosquito community structure in a tropical dry forest in Brazil.METHODS: Culicidae were collected during dry and wet seasons in cattle presence and absence between August 2008 and October 2010 and assessed using multivariate statistical models.RESULTS: Cattle removal did not significantly alter Culicidae species richness and abundance. However, alterations were noted in Culicidae community composition.CONCLUSIONS: This is the first study to evaluate the impact of cattle removal on Culicidae community structure in Brazil and demonstrates the importance of assessing ecological parameters such as community species composition.

  2. Exploring New Thermal Fog and Ultra-Low Volume Technologies to Improve Indoor Control of the Dengue Vector, Aedes aegypti (Diptera: Culicidae)

    Science.gov (United States)

    2014-07-01

    Dengue : guide- lines for diagnosis, treatment , prevention and control. WHO, Geneva, Switzerland. Zar, J. H. 1999. Biostatistical Analysis, 4th ed... Dengue Vector, Aedes aegypti (Diptera: Culicidae) JAMES F. HARWOOD,1,2 MUHAMMAD FAROOQ,1 ALEC G. RICHARDSON,1 CARL W. DOUD,1 JOHN L. PUTNAM,3 DANIEL E...vector, Aedes aegypti (L.), inside human habitations must be performed quickly and efÞciently to reduce the risk of transmission during dengue

  3. Grass Pollen Affects Survival and Development of Larval Anopheles arabiensis (Diptera: Culicidae).

    Science.gov (United States)

    Asmare, Yelfwagash; Hopkins, Richard J; Tekie, Habte; Hill, Sharon R; Ignell, Rickard

    2017-09-01

    Nutrients in breeding sites are critical for the survival and development of malaria mosquitoes, having a direct impact on vectorial capacity. Yet, there is a limited understanding about the natural larval diet and its impact on the individual fitness of mosquitoes. Recent studies have shown that gravid Anopheles arabiensis Patton (Diptera: Culicidae) are attracted by and oviposit in grass-associated habitats. The pollen provided by these grasses is a potential source of nutrients for the larvae. Here, we assess the effect of Typha latifolia L. (Poales: Typhaceae), Echinochloa pyramidalis Lamarck, Pennisetum setaceum Forsskål, and Zea mays L. pollen on larval survival and rate of development in An. arabiensis under laboratory conditions. In addition, we characterize the carbon to nitrogen ratio and the size of pollen grains as a measure of diet quality. Carbon-rich pollen with a small grain size (T. latifolia and P. setaceum; 9.7 ± 0.3 × 103 and 5.5 ± 0.2 × 104 µm3, respectively) resulted in enhanced rates of development of An. arabiensis. In contrast, the larva fed on the nitrogen-rich control diet (TetraMin) was slower to develop, but demonstrated the highest larval survival. Larvae fed on carbon-rich and large-grained Z. mays pollen (4.1 ± 0.2 × 105 µm3) survived at similar levels as those fed on the control diet and also took a longer time to develop compared with larvae fed on the other pollens. While males and females did not appear to develop differently on the different pollen diets, males consistently emerged faster than their female counterparts. These results are discussed in relation to integrated vector management. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  4. Overwintering in the Bamboo Mosquito Tripteroides bambusa (Diptera: Culicidae) During a Warm, But Unpredictably Changing, Winter.

    Science.gov (United States)

    Chaves, Luis Fernando; Jian, Jiun-Yu; Moji, Kazuhiko

    2017-12-22

    The bamboo mosquito, Tripteroides bambusa (Yamada) (Diptera: Culicidae), is a common insect across forested landscapes in Japan. Several studies have reported its overwintering as larvae and eggs, in both natural and artificial water containers. Nevertheless, it is unclear how sensitive this mosquito species is to changes in weather patterns associated with global warming. The El Niño event of 2015 through 2016 was one of the strongest on record and provided an ideal scenario for observations on the overwintering of the bamboo mosquito during a winter predicted to be unusually warm. Thus, we set oviposition traps in mid October 2015 and made weekly observations, from December 2015 to May 2016, on bamboo mosquito larval recruitment and pupation in Nagasaki, Japan. We found that larvae were pupating as late as the first week of January (prior records from the study site indicated mosquito pupation ended by mid-late October) and that pupation resumed in mid April (one month earlier than previous records at the study site). We also found that fourth instar larvae were able to survive in frozen oviposition traps following an extremely unusual snowstorm and cold spell and that recruitment of larvae from eggs happened after this unusual event. Our analysis suggested that overwintering and metamorphosis of the bamboo mosquito is sensitive to average and extreme temperatures, the latter measured by temperature kurtosis. Our results highlight the need to better understand changes in overwintering strategies in insects, and associated trade-offs and impacts on population dynamics, in light of climate change. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Evaluation of indigenous plant extracts against the malarial vector, Anopheles stephensi (Liston) (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu

    2011-07-01

    Since ancient times, plant and microbial products were used in various aspects. However, their use against insects decreased when chemical products became developed. Recently, concerns increased with respect to public health and environmental security requiring detection of natural products that may be used against insects. In this study, mosquito Larvicidal and ovicidal activity of crude hexane, ethyl acetate, benzene, chloroform, and methanol extracts of the leaf of three plants, Eclipta alba, Cardiospermum halicacabum, and Andrographis paniculata, were tested against the early third-instar larvae of Anopheles stephensi (Liston) (Diptera: Culicidae). The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in methanol extract of A. paniculata, E. alba, and C. halicacabum against the larvae of A. stephensi (LC(50) = 79.68, 112.56, and 133.01 ppm; LC(90) = 154.66, 220.68, and 270.72 ppm), respectively. Mean percent hatchability of the ovicidal activity was observed 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Mortality of 100% with methanol and ethyl acetate extract of A. paniculata and methanol extract of E. alba were exerted at 200 ppm and methanol and benzene extract of C. halicacabum exerted at 150 ppm. This is an ideal eco-friendly approach for the control of the malaria vector, A. stephensi. Therefore, this study provides first report on the larvicidal and ovicidal activities against malaria vector, A. stephensi of E. alba plant extracts.

  6. [The presence of mosquitoes (Diptera: Culicidae) in flood containment reservoirs in the eastern region of the City of São Paulo, Brazil].

    Science.gov (United States)

    Silvério, Edna de Cássia; Urbinatti, Paulo Roberto

    2011-01-01

    Alterations in the environment contribute to changes in weather patterns, which cause an increase in rainfall, which causes flooding. Flooding has been addressed by building reservoirs, called piscinões, to contain the excess rain. In this report, we evaluated the Culicidae fauna of epidemiological importance in the reservoirs of Caguaçu and Inhumas. Monthly collections were performed in both reservoirs, which are situated in the Eastern section of the City of São Paulo. Monthly collections of Culicidae were undertaken using the entomological scoop method and a battery aspirator during the period between March 2006 and February 2007. Descriptive statistical and simple linear regression analyses of the data were carried out. A total of 8,917 Culicidae mosquitoes were collected. The majority of the insects captured were of Culex (Culex) quinquefasciatus, representing 98.9% of the specimens identified in the Inhumas and 95.2% of those identified in Caguaçu. In the Caguaçu reservoir, the greatest frequency of immature mosquitoes was observed in the spillway (61%). In the Inhumas reservoir, the greatest occurrence of immature Culicidae was detected in the channel (42.6%). The linear regression analysis showed that 87% of the larvae in the third and fourth stages and 60% of the pupae were collected during periods of rainfall. In the Inhumas reservoir, 36% of the larvae and 18% of the pupae were collected during periods of rainfall. Culex quinquefasciatus, a vector for agents of filariasis and arbovirus diseases and a nuisance to the human population, was frequent in both environments. Methods of control of the species in the studied dams are necessary to reduce their epidemiological potential.

  7. Immature culicidae (Diptera collected from the Igapó lake located in the urban area of Londrina, Paraná, Brazil

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    José Lopes

    2002-12-01

    Full Text Available The Igapó lake dam is located in an urban area in Londrina, Paraná, Brazil. A one year study of the Culicidae immature forms was conducted in this ecosystem. From a total of 962 collected larvae following genera were identified: Anopheles (59.36%, Culex (19.65% Aedeomyia (19.23% Aedes (1.50%, and Uranotaenia (0.10%. The 10 most abundant species were Anopheles strodei, Aedeomyia squamipennis, Culex (Melanoconium spp., Culex mollis, Anopheles oswaldoi, Anopheles evansae, Culex coronator, Culex quinquefasciatus, Anopheles argyritarsis and Aedes terrens respectively. An. strodei prevailed with greater averages during July and September, showing a significant negative lineal correlation in relation to the rainfall. Ad. squamipennis showed a positive lineal correlation with the temperature with smaller population averages during June, August and September of 1997. Cx. (Melanoconium spp. populations were constant throughout the year. High Culicidae population density could bring problems to quality of human life, thus strong measures to avoid and control of mosquito population growth in the lake are recommended.O lago Igapó é um conjunto de quatro represas localizadas na área urbana de Londrina, Paraná, Brasil, com condições propícias para procriação de culicídeos. A presente pesquisa teve como objetivo verificar a culicideofauna de imaturos neste lago, monitorando possíveis vetores de agentes patogênicos. Durante um ano coletou-se 962 imaturos que se distribuíram nos seguintes gêneros: Anopheles (59,36%, Culex (19,65% Aedeomyia (19,23% Aedes (1,50%, and Uranotaenia (0,10%. As espécies mais abundantes foram Anopheles strodei, Aedeomya squamipennis, Culex. (Melanoconium spp., Culex mollis, Anopheles oswaldoi, Anopheles evansae, Culex coronator, Culex quinquefasciatus, Anopheles argyritarsis e Aedes terrens respectivamente. An. strodei, prevaleceu com grandes médias populacionais de Julho a Setembro, mostrando uma correlação linear

  8. A Qualitative Evidence of the Breeding Sites of Anopheles arabiensis Patton (Diptera: Culicidae) in and Around Kassala Town, Eastern Sudan.

    Science.gov (United States)

    Hamza, Asma Mahmoud; El Rayah, El Amin

    2016-01-01

    Anopheles arabiensis Patton (Diptera: Culicidae) is considered the most efficient malaria vector in eastern Sudan. This study aims to characterize the breeding sites of An. arabiensis throughout the year in and around Kassala town, eastern Sudan. Diverse larval habitat types were visited and characterized based on the habitat type and chemical composition. Mosquito larvae were found in many diverse habitats. During the rainy season, rain pools and water bodies created by the seasonal Gash River serve as the main breeding sites. In the dry season, irrigation canals, seepage from water pipes, neglected wells, artificial containers, and man-made ditches serve as the main breeding sites. Breeding water showed a pH of 7.9 and a low concentration of the total dissolved salts. The results of this study may be considered in planning and implementing larval control programs in the area.

  9. Pengaruh penggunaan repelen masal jangka panjang pada suatu pemukiman terhadap keberadaan nyamuk Aedes aegypti (L. (Diptera: Culicidae

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    Upik Kesumawati Hadi

    2017-02-01

    Full Text Available A Study of The Effect of Mass Treatment of Repellent on Aedes aegypti (L. (Diptera: Culicidae. Larval populations was carried out during 14 week period at Laladon village Bogor. A total of 3684 respondents were treated and 202 houses were surveyed for house index (HI, container index (CI, and breteau index (BI. The results showed that long-term mass treatments were effective to decrease 64.85% of the HI, 27.15% CI and 13.57% of BI, up to three weeks after the last application of the repellent. Final checks which were done four weeks later resulted HI as low as 13.86%, CI 7.68%, and BI 3.84%, compared to those at the beginning of the survey which were 73.27%, 31.87% and 15.93%, respectively.

  10. Mosquitocidal activities of thyme oils (Thymus vulgaris L.) against Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Pavela, Roman; Vrchotová, Nadezda; Tríska, Jan

    2009-10-01

    Oil samples from four chemotypes of Thymus vulgaris were tested for mosquitocidal activity. Oil compounds were analyzed by gas chromatography-mass spectrometry (GC-MS). The different compositions of the oils varied in their biological activity as well. Larvicidal efficiency was determined for the most significant oil thymol type (T), namely the lowest doses LD(50) 32.9 and 14.2 mg/l for the third and fourth instars, respectively. The oils also showed very good efficiency with respect to mortality and to the percentage of adult emergence upon short-term exposure in water treated by lethal doses of individual oils. Although the larvae were left in treated water for only 5 h, mortality corresponding to LD(50) was determined after 24 h, i.e., between 49% and 63%. Furthermore, mortality increased significantly in relation to time of exposure, and total mortality of the larvae at the end of their development was about 90%. Such significant mortality was also naturally reflected in the total emergence of adults. In the control sample, there was 77% adult emergence from the larvae, whereas in oils, there was only from 5.3% to 16% emergence. The greatest fumigate efficiency was found for T and linalool chemotypes, with an LC(50) for 24 h of exposure being 1.1 and 1.8 mg/l, respectively. Essence T was also most efficient in the tarsal test, with LD(50) of 44 microg/cm(2) and LD(90) of 63 microg/cm(2). High antioviposition efficiency was found in all tested oils.

  11. A New Subgenus of CULEX in the Neotropical Region (Diptera: Culicidae)

    Science.gov (United States)

    1992-11-01

    subgenus in the the Greek nouns phtwna.v (m, deceiver, cheat. New World, and the results of the present impostor: combining form /phnaco’-) and study...mistaken for members of the characters oftthe lar\\al stage, subgenus (’tlehv. The name is feminine in The affinities of tth’nao,,. via arc un- gender. The

  12. A New Species of Culex (melanoconion) from Southern South America (Diptera: Culicidae)

    Science.gov (United States)

    1984-01-01

    armature: Cibarial bar (Fig. 4) concave; with 9 stout, curved, blunt teeth. Cibarial dome nearly circular in outline, produced anteriorly in middle...setae on posterodorsal margin. Pleural setae (Fig. 1C) golden brown, darker on prealar knob: about 10 upper proepisternal, 4 or 5 prealar, 5-8 upper...Jakob, Division of Vector-Borne Viral Diseases , Centers for Disease Control, Ft. Collins, CO, and Ronald A. Ward and Thomas J. Zavortink

  13. Culicidae (Diptera selection of humans, chickens and rabbits in three different environments in the province of Chaco, Argentina

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    Marina Stein

    2013-08-01

    Full Text Available Studies were conducted to determine the selection of humans, chickens and rabbits by Culicidae in three different environments in the province of Chaco, Argentina. Mosquitoes were collected fortnightly using cylindrical metal traps containing animal bait (chickens and rabbits. The mosquitoes were collected between June 2001-May 2002. During the same period and with the same frequency, mosquitoes biting the human operators of the traps were collected during the first 15 min of exposure within different time intervals: from 09:00 am-11:00 am, 01:00 pm-03:00 pm, 05:00 pm-07:00 pm and 09:00 pm-10:00 pm. A total of 19,430 mosquitoes of 49 species belonging to 10 genera were collected. Culex species mainly selected chicken bait and Wyeomyia species selected rabbit bait. Ochlerotatus and Psorophora species were more abundant in rabbit-baited traps. Anopheles triannulatus, Coquillettidia nigricans, Ochlerotatus scapularis, Mansonia titillans and Psorophora albigenu showed a strong attraction for human bait. The Anopheles, Coquillettidia, Culex and Mansonia species were more active between 05:00 pm-09:00 pm, while Ochlerotatus, Psorophora, Haemagogus and Wyeomyia were most active from 09:00 am-07:00 pm. This study provides additional information about the biology and ecology of arbovirus vectors in Chaco.

  14. Spatiotemporal variation of mosquito diversity (Diptera: Culicidae) at places with different land-use types within a neotropical montane cloud forest matrix.

    Science.gov (United States)

    Abella-Medrano, Carlos Antonio; Ibáñez-Bernal, Sergio; MacGregor-Fors, Ian; Santiago-Alarcon, Diego

    2015-09-24

    Land-use change has led to a dramatic decrease in total forest cover, contributing to biodiversity loss and changes of ecosystems' functions. Insect communities of medical importance can be favored by anthropogenic alterations, increasing the risk of novel zoonotic diseases. The response of mosquito (Diptera: Culicidae) abundance and richness to five land-use types (shade coffee plantation, cattle field, urban forest, peri-urban forest, well-preserved montane cloud forest) and three seasons ("dry", "rainy" and "cold") embedded in a neotropical montane cloud forest landscape was evaluated. Standardized collections were performed using 8 CDC miniature black-light traps, baited with CO2 throughout the year. Generalized additive mixed models were used to describe the seasonal and spatial trends of both species richness and abundance. Rank abundance curves and ANCOVAs were used to detect changes in the spatial and temporal structure of the mosquito assemblage. Two cluster analyses were conducted, using 1-βsim and the Morisita-Horn index to evaluate species composition shifts based on incidences and abundances. A total of 2536 adult mosquitoes were collected, belonging to 9 genera and 10 species; the dominant species in the study were: Aedes quadrivittatus, Wyeomyia adelpha, Wy. arthrostigma, and Culex restuans. Highest richness was recorded in the dry season, whereas higher abundance was detected during the rainy season. The urban forest had the highest species richness (n = 7) when compared to all other sites. Species composition cluster analyses show that there is a high degree of similarity in species numbers across sites and seasons throughout the year. However, when considering the abundance of such species, the well-preserved montane cloud forest showed significantly higher abundance. Moreover, the urban forest is only 30 % similar to other sites in terms of species abundances, indicating a possible isolating role of the urban environment. Mosquito

  15. Diversidade de Culicidae durante os períodos crepusculares em bioma de Floresta Atlântica e paridade de Anopheles cruzii (Diptera: Culicidae Diversity of Culicidae during the crepuscular periods in Atlantic Forest biome and parity of Anopheles cruzii (Diptera: Culicidae

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    Ana C. D. Bona

    2008-03-01

    Full Text Available O objetivo da investigação foi analisar a variação da diversidade e abundância das espécies de Culicidae e sua relação com algumas variáveis ambientais, bem como estimar a taxa de paridade de Anopheles cruzii Dyar & Knab, 1908. O estudo foi desenvolvido em Floresta Ombrófila Densa da Mata Atlântica, localizada no Estado do Paraná, denominada de Floresta Estadual do Palmito. As capturas foram executadas quinzenalmente, de dezembro 2006 a março 2007, com a técnica de "aspiração menor", nos crepúsculos vespertino e matutino, iniciando antes dos crepúsculos e finalizando após os crepúsculos. Foram detectadas 25 espécies, sendo as mais abundantes, Anopheles cruzii (65,2%, Culex sachettae Sirivanakarn & Jacob, 1982 (11,2% e Anopheles bellator Dyar & Knab, 1906 (8,5%. De acordo com análise de variância, ocorreu diferença significativa na freqüência entre os períodos crepusculares para seguintes espécies: Aedes scapularis (Rondone, 1848 (p = 0,03651, Coquillettidia chrysonotum (Peryassu, 1922 (p = 0,00795, Mansonia fonsecai (Pinto, 1932 (p = 0,00804, e Runchomyia theobaldi Lane & Cerqueira, 1934 (p = 0,01996. Não houve correlação significativa com a abundância das principais espécies capturadas e as médias dos fatores abióticos avaliados. A taxa de paridade de Anopheles cruzii atingiu média percentual de 48%, não existindo correlação entre a abundância e a taxa de paridade. O crepúsculo exerce influência no comportamento apetente das espécies de Culicidae. A comparação de similaridade entre os crepúsculos apontou para elevada semelhança da composição específica. Anopheles cruzii atingiu dominância nos períodos vespertino e matutino, sendo a diversidade de forma geral reduzida nestes períodos.The aim of this investigation was to know the diversity and abundance of Culicidae associating with the climatic factors and obtaining the parity of Anopheles cruzii Dyar & Knab, 1908. The study was developed in a

  16. Efficacy of indigenous plant extracts on the malaria vector Anopheles subpictus Grassi (Diptera: Culicidae)

    Science.gov (United States)

    Elango, G.; Zahir, A. Abduz; Bagavan, A.; Kamaraj, C.; Rajakumar, G.; Santhoshkumar, T.; Marimuthu, S.; Rahuman, A. Abdul

    2011-01-01

    Background & objectives: Mosquito control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of plant origin may serve as suitable alternative biocontrol techniques in the future. The purpose of the present study was to assess the ethyl acetate, acetone and methanol extracts of Andrographis paniculata, Eclipta prostrata and Tagetes erecta leaves tested for oviposition-deterrent, ovicidal and repellent activities against malaria vector, Anopheles subpictus Grassi (Diptera: Culicidae). Methods: The dried leaves of the three plants were powdered mechanically and extracted with ethyl acetate, acetone and methanol. One gram of crude extract was first dissolved in 100 ml of acetone (stock solution). From the stock solution, test solution concentrations of 31.21- 499.42 mg/l for oviposition- deterrence assay and repellency and 15.60 - 998.85 mg/l were used in ovicidal assay. The percentage oviposition- deterrence, hatching rate of eggs and protection time were calculated. One-way analysis of variance was used for the multiple concentration tests and for per cent mortality to determine significant treatment differences. Results: The percentage of effective oviposition repellency was highest at 499.42 mg/l and the lowest at 31.21 mg/l in ethyl acetate, acetone and methanol extracts of A. paniculata, E. prostrata and T. erecta. The oviposition activity index (OAI) value of ethyl acetate, acetone and methanol extracts of A. paniculata, E. prostrata and T. erecta at 499.42 mg/l were -0.91, -0.93, -0.84, -0.84, -0.87, -0.82, -0.87, -0.89 and -0.87, respectively. Mortality (no egg hatchability) was 100 per cent with ethyl acetate and methanol extracts of A. paniculata, E. prostrata and T. erecta at 998.85 mg/l. The maximum adult repellent activity was observed at 499.42 mg/l in ethyl acetate extracts of A. paniculata, E. prostrata and methanol extracts of T. erecta, and the mean complete protection time ranged from 120 to 150 min with

  17. Aedes aegypti survival in the presence of Toxorhynchites violaceus (Diptera: Culicidae) fourth instar larvae

    National Research Council Canada - National Science Library

    Albeny, Daniel S; Martins, Gustavo F; Andrade, Mateus R; Krüger, Rodrigo F; Vilela, Evaldo F

    2011-01-01

    ... of Toxorhynchites spp. larvae (FOCKS 2007). Toxorhynchites spp. larvae live in natural and artificial water containers and are predators of Culicidae, e.g. Aedes triseriatus (Say, 1823) and Aedes ...

  18. Monthly prevalence and diversity of mosquitoes (Diptera: Culicidae in Fars Province, Southern Iran

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    Davood Keshavarzi

    2017-02-01

    Full Text Available Objective: To get new data about the ecology of mosquitoes, which would be valuable to develop programs for future provision of mosquito controls in the study area. Methods: During April to September 2012, larvae of mosquitoes were collected from six counties in south of Fars Province using dipping method. Characteristics of larval breeding places were considered based on water conditions. Species diversity was examined in terms of alpha and beta measures, with the intent of comparing mosquito diversity according to the typology of regions. Results: During this investigation, totally, 5 057 larvae of mosquitoes belonging to 5 genera and 17 different mosquito species were recognized, namely, Anopheles dthali, Anopheles fluviatilis, Anopheles stephensi, Anopheles superpictus, Culex quinquefasciatus (Cx. quinquefasciatus, Culex mimeticus, Culex perexiguus, Culex pipiens (Cx. pipiens, Culex tritaeniorhynchus, Culex theileri (Cx. theileri, Culex tritaeniorhynchus, Culex sinaiticus, Culex torrentium, Culex modestus, Ochlerotatus caspius, Culiseta longiareolata and Aedes vexans (Ae. vexans. This is the first record of Ae. vexans, Culex perexiguus and Culex modestus in the Province. Cx. pipiens (27.3%, Cx. theileri (15.9% and Cx. quinquefasciatus (9.4% were the most abundant species found respectively. Cx. pipiens reached the highest density in August and July, while Cx. theileri, Cx. quinquefasciatus and Ae. vexans were found in high numbers in June. Diversity analysis indicated the highest species diversity in the Mohr County (Margalef index of 1.41 and Shannon index of 1.7 and the lowest species diversity in the Lamerd County (Margalef index of 0.33 and Shannon index of 0.38. Conclusions: Regarding to this research, there are some potential vectors of medical and veterinary importance in Fars Province. Results of the present study may serve as a basis for risk assessment of emerging mosquito-borne diseases.

  19. First record of genus Toxorhynchites Theobald (Diptera, Culicidae) in Mata Atlântica, Viçosa, Minas Gerais State, Brazil

    OpenAIRE

    Daniel Simões Albeny; Cassiano Sousa Rosa; Lívia Maria Silva Ataíde; Evaldo Ferreira Vilela

    2010-01-01

    Durante os meses de março e abril de 2007 foi verificada a presença do gênero Toxorhynchites (Diptera, Culicidae) em fragmentos de Mata Atlântica no município de Viçosa, Minas Gerais, Brasil. No experimento foram utilizadas 500 armadilhas de oviposição. Registrando-se, pela primeira vez na região de Viçosa o gênero Toxorhynchites, sendo as espécies T. pusillus (Costa Lima, 193 1) e T. theobaldi (Dyar & Knab, 1906) encontradas pela primeira vez no Estado de Minas Gerais. As espécies relatadas ...

  20. Astronotus ocellatus (Cichlidae: Pisces and Macropodus opercularis (Anabatidae: Pisces as predators of immature Aedes fluviatilis (Diptera: Culicidae and Biomphalaria glabrata (Mollusca: Planorbidae

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    Rotraut A. G. B. Consoli

    1991-12-01

    Full Text Available Two fish species, Astronotus ocellatus (Cichlidae and Macropodus opercularis (Anabatidae were tested for predacious behavior toward immature mosquitoes (Aedes fluviatili9s, Diptera: Culicidae and schistosomiasis snail hosts (Biomphalaria glabrata, Mollusca: Planorbidae, in the presence or absence of non-living food and laboratory conditions. A. ocellatus, a species indigenous to Brazil, was a very efficient predator of both organisms (alpha=1,05; M. operculatis, an exotic species, preyed well on immature mosquitoes, but small snails and snail egg-masses were ingested only irregulary. Both fish species seemed to prefer live to non-living food.

  1. Preferencia de hospedadores de Culicidae (Diptera recolectados en el centro de la Argentina Host preference of Culicidae (Diptera collected in central Argentina

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    Walter R. Almirón

    1995-04-01

    Full Text Available Con el propósito de estudiar la preferencia de hospedadores vertebrados por mosquitos hembras, durante 2 períodos octubre-abril (primavera-verano, se realizaron muestreos cada 15 días en Córdoba y Cosquín (Argentina. Se utilizaron trampas de latón con cebo animal: anfibios (sapos, aves (pollos, mamíferos (conejos y reptiles (tortugas. El 92,9% de los especímenes recolectados pertenecen al género Culex, mientras que un 7,0% corresponde a Aedes y el 0,02% restante a Psorophora ciliata, única especie que se capturó de ese género. En trampas con pollo se recolectó el mayor número de hembras (68,7%, siguiendo en orden las trampas con conejos (29,9%, con tortugas (0,8% y con sapos (0,5%, por lo tanto, la mayoría de los mosquitos entraron en las trampas con hospedadores homeotermos. Culex dolosus se alimentó sobre todos los cebos, mientras que Cx. acharistus, Cx. chidesteri y Cx. quinquefasciatus se alimentaron sobre pollos, conejos y tortugas; Ae. albifasciatus, Ae. scapularis, Cx. bidens y Cx. coronator lo hicieron sobre ambos hospedadores homeotermos; Cx. apicinus, Cx. maxi, Cx. saltanensis y Cx. spinosus se alimentaron solamente sobre pollos y Ps. ciliata sobre conejos.Com o propósito de estudar a preferência de mosquitos fêmeas por hospedeiros vertebrados, realizaram-se amostragens quinzenais nas cidades de Córdoba e Cosquín (Argentina, durante o período de outubro a abril (primavera-verão, por dois anos consecutivos. Utilizaram-se armadilhas com iscas animais: anfíbios, aves, mamíferos e répteis. Dos espécimes coletados, 92,9% pertenciam ao gênero Culex, 7,0% a Aedes e 0,02% a Psorophora ciliata, única espécie coletada desse gênero. A maior proporçãoo de fêmeas (68,7% foi capturada em armadilhas iscadas com galinhas, seguindo-se em ordem as armadilhas com coelhos (29,9%, com tartarugas (0,8% e com anfíbios (0,05%. Assim, a maioria dos mosquitos foi coletada em armadilhas com hospedeiros homeotermos. Culex

  2. Nuevos registros y distribución de mosquitos de la Argentina (Diptera: Culicidae) New records and distribution of mosquitoes from Argentina (Diptera: Culicidae)

    OpenAIRE

    Rossi, Gustavo C; Lestani, Eduardo A.; J. Martín D'Oria

    2006-01-01

    Se presentan 21 nuevos registros de especies y se amplía la distribución de otras 12 especies de los géneros Anopheles Meigen, Coquillettidia Dyar, Culex L., Haemagogus Williston, Ochlerotatus Lynch Arribalzaga, Onirion Harbach y Peyton, Orthopodomyia Theobald, Psorophora Robineau-Desvoidy, Sabethes Robineau-Desvoidy, Stegomyia Theobald, Toxorhynchites Theobald. Se incluyen comentarios y cambios de estatus para especies de Howardina Theobald, Ochlerotatus y Lutzia (Theobald). Actualmente, en ...

  3. Urban mosquito species (Diptera: Culicidae) of dengue endemic communities in the Greater Puntarenas area, Costa Rica

    Science.gov (United States)

    Troyo, Adriana; Solano, Mayra E.; Avendaño, Adrián; Beier, John C.

    2010-01-01

    Field studies were conducted to determine the mosquito species richness in the urban area of Greater Puntarenas in Costa Rica. Two cross-sectional entomological surveys were performed in seven localities of Puntarenas: one survey was performed during the wet season and the other during the dry season. The sections evaluated were determined by applying a stratified cluster sampling method using satellite imagery, and a sample of 26 cells (100×100m) was selected for the study. The number of cells per locality was proportional to the area of each locality. The presence of mosquito larvae and pupae in water-filled artificial and natural containers was determined in each cell. Infestation was expressed as a diversity index per type of container (Ii). Eight types of larvae were identified (Aedes aegypti, Culex quinquefasciatus, Culex interrogator, Culex nigripalpus, Culex corniger, Culex tarsalis, Limatus durhamii and Toxorhynchites theobaldi) and in two cases it was only possible to identify the genus (Culex sp. and Uranotaenia sp.). A. aegypti was the most common species followed by C. quinquefascitus. Diversity of wet environments can explain the co-occurrence of various culicid species in some localities. Although A. aegypti is the only documented disease vector in the area, C quinquefasciatus, C. nigripalpus, and the other species of Culex could be considered potential vectors of other pathogens. The presence and ecology of all mosquito species should be studied to optimize surveillance and prevention of dengue and to prevent the emergence of other mosquito-transmitted diseases. PMID:20073347

  4. INVENTORY OF MOSQUITOES (DIPTERA: CULICIDAE IN CONSERVATION UNITS IN BRAZILIAN TROPICAL DRY FORESTS

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    Cleandson Ferreira SANTOS

    2015-06-01

    Full Text Available In Brazil, most studies of the Culicidae family are concentrated in rainforest regions. As such, there is a lack of knowledge regarding the diversity of Culicidae in regions with different climatic and vegetational characteristics. The aim of this study was to compile an inventory of Culicidae in protected areas of the semi-arid region of the state of Minas Gerais, Brazil, in order to better understand the diversity of the family within this region. The study was conducted across four protected areas in the northern region of the state, in tropical dry forest (TDF fragments. Sampling methods included Shannon trap and CDC light trap, as well as active collection. A total of 11,219 mosquito specimens were collected between August 2008 and July 2012, belonging to 11 genera and 45 species; 15 new records for the state of Minas Gerais were registered, as well as 26 new records for semi-arid regions within the state. The high number of new Culicidae records in this region demonstrates the importance of inventory studies for increasing the knowledge of culicid biodiversity in Minas Gerais, and in particular within semi-arid regions of the state.

  5. INVENTORY OF MOSQUITOES (DIPTERA: CULICIDAE) IN CONSERVATION UNITS IN BRAZILIAN TROPICAL DRY FORESTS.

    Science.gov (United States)

    Santos, Cleandson Ferreira; Silva, Alex Chavier; Rodrigues, Raquel Andrade; de Jesus, Jamilli Sanndy Ramos; Borges, Magno Augusto Zazá

    2015-01-01

    In Brazil, most studies of the Culicidae family are concentrated in rainforest regions. As such, there is a lack of knowledge regarding the diversity of Culicidae in regions with different climatic and vegetational characteristics. The aim of this study was to compile an inventory of Culicidae in protected areas of the semi-arid region of the state of Minas Gerais, Brazil, in order to better understand the diversity of the family within this region. The study was conducted across four protected areas in the northern region of the state, in tropical dry forest (TDF) fragments. Sampling methods included Shannon trap and CDC light trap, as well as active collection. A total of 11,219 mosquito specimens were collected between August 2008 and July 2012, belonging to 11 genera and 45 species; 15 new records for the state of Minas Gerais were registered, as well as 26 new records for semi-arid regions within the state. The high number of new Culicidae records in this region demonstrates the importance of inventory studies for increasing the knowledge of culicid biodiversity in Minas Gerais, and in particular within semi-arid regions of the state.

  6. Larvicidal Activity of Essential Oils from the Leaves and Fruits of Nutmeg (Myristica fragrans Houtt Against Aedes aegypti (Diptera: Culicidae

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    Anne Carolina

    2016-07-01

    Full Text Available The aim of this research was to examine the larvicidal activity of essential oil (EO extracted from nutmeg (Myristica fragrans Houtt leaves and fruits by steam distillation, and to analyze its chemical compounds. The EO yield of nutmeg leaves and fruits collected from the same tree was 0.66% and 0.30%, respectively. Larvicidal tests with the EO were carried out against Aedes aegypti (L. (Diptera: Culicidae. The concentrations of nutmeg EO used for the larvicidal assay were 50, 100, 150, 200, and 250 μg/mL. The results showed that fruit oil was more toxic than the leaf oil. LC50 values of leaf and fruit EOs were 133.8 and 110.1 µg/mL, respectively. The chromatogram of GC-MS showed that the chemical components in nutmeg leaf and fruit EOs were dominated by α-pinene, sabinene, β-pinene, delta-3-carene, limonene, β-phellandrene, α-terpinolene, linalool, safrole, croweacin, and myristicin.

  7. Chemical Composition and Larvicidal Activity of Essential Oils Extracted from Brazilian Legal Amazon Plants against Aedes aegypti L. (Diptera: Culicidae

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    Clarice Noleto Dias

    2015-01-01

    Full Text Available The mosquito Aedes aegypti L. (Diptera: Culicidae is the major vector of dengue and chikungunya fever. The lack of effective therapies and vaccines for these diseases highlights the need for alternative strategies to control the spread of virus. Therefore, this study investigated the larvicidal potential of essential oils from common plant species obtained from the Chapada das Mesas National Park, Brazil, against third instar A. aegypti larvae. The chemical composition of these oils was determined by gas chromatography coupled to mass spectrometry. The essential oils of Eugenia piauhiensis Vellaff., Myrcia erythroxylon O. Berg, Psidium myrsinites DC., and Siparuna camporum (Tul. A. DC. were observed to be mainly composed of sesquiterpene hydrocarbons. The essential oil of Lippia gracilis Schauer was composed of oxygenated monoterpenes. Four of the five tested oils were effective against the A. aegypti larvae, with the lethal concentration (LC50 ranging from 230 to 292 mg/L after 24 h of exposure. Overall, this work demonstrated the possibility of developing larvicidal products against A. aegypti by using essential oils from the flora of the Brazilian Legal Amazon. This in turn demonstrates the potential of using natural resources for the control of disease vectors.

  8. Chemical Composition and Larvicidal Activity of Essential Oils Extracted from Brazilian Legal Amazon Plants against Aedes aegypti L. (Diptera: Culicidae).

    Science.gov (United States)

    Dias, Clarice Noleto; Alves, Luciana Patrícia Lima; Rodrigues, Klinger Antonio da Franca; Brito, Maria Cristiane Aranha; Rosa, Carliane Dos Santos; do Amaral, Flavia Maria Mendonça; Monteiro, Odair Dos Santos; Andrade, Eloisa Helena de Aguiar; Maia, José Guilherme Soares; Moraes, Denise Fernandes Coutinho

    2015-01-01

    The mosquito Aedes aegypti L. (Diptera: Culicidae) is the major vector of dengue and chikungunya fever. The lack of effective therapies and vaccines for these diseases highlights the need for alternative strategies to control the spread of virus. Therefore, this study investigated the larvicidal potential of essential oils from common plant species obtained from the Chapada das Mesas National Park, Brazil, against third instar A. aegypti larvae. The chemical composition of these oils was determined by gas chromatography coupled to mass spectrometry. The essential oils of Eugenia piauhiensis Vellaff., Myrcia erythroxylon O. Berg, Psidium myrsinites DC., and Siparuna camporum (Tul.) A. DC. were observed to be mainly composed of sesquiterpene hydrocarbons. The essential oil of Lippia gracilis Schauer was composed of oxygenated monoterpenes. Four of the five tested oils were effective against the A. aegypti larvae, with the lethal concentration (LC50) ranging from 230 to 292 mg/L after 24 h of exposure. Overall, this work demonstrated the possibility of developing larvicidal products against A. aegypti by using essential oils from the flora of the Brazilian Legal Amazon. This in turn demonstrates the potential of using natural resources for the control of disease vectors.

  9. Susceptibility of larvae of Aedes aegypti (Linnaeus (Diptera: Culicidae to entomopathogenic nematode Heterorhabditis bacteriophora (Poinar (Rhabditida: Heterorhabditidae

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    María L. PESCHIUTTA

    2014-01-01

    Full Text Available Aedes aegypti (Linnaeus (Diptera: Culicidae es vector de los agentes etiológicos de la fiebre amarilla y del dengue. Una alternativa al control químico de este vector es el uso de agentes biológicos. Los nematodos entomopatógenos son efectivos en el control de plagas. La infectividad y el ciclo de vida de un aislado argentino de Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae en larvas de A. aegypti se registró por primera vez bajo condiciones de laborato - rio. Para cada unidad experimental, 30 larvas de mosquito de segundo estadio fueron expuestas a 8 dosis del nematodo (0:1, 1:1, 5:1, 15:1, 100:1, 500:1, 750:1, 1500:1. Los juveniles infectivos (JIs utilizados fueron multiplicados sobre Galleria mellonella (Lepidoptera: Pyralidae. La continuidad infectiva de los JIs obtenidos de A. aegypti fue probada aplicándolos en una dosis de 100:1 sobre larvas del mosquito . Las tasas de mortalidad fueron de 0% a 84%. El número de nematodos desarrollados dentro de la larva de mosquito, la mortalidad larval y los nuevos JIs se incrementaron con el aumento de la dosis de nematodos. Los resultados indican que H. bacteriophora es capaz de infectar larvas de A. aegypti , se desarrolla y produce nuevos JIs, permitiendo la continuidad de su ciclo de vida.

  10. Odonate Nymphs: Generalist Predators and their Potential in the Management of Dengue Mosquito, Aedes aegypti (Diptera: Culicidae

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    Waseem Akram

    2016-01-01

    Full Text Available Background: Dengue is amongst the most serious mosquito-borne infectious disease with hot spots in tropical and subtropical parts of the world. Unfortunately, no licensed vaccine for the disease is currently available in medicine markets. The only option available is the management of dengue vector mosquito, Aedes aegypti (Diptera: Culicidae.Method: Predatory potential of five odonate nymphs namely Anax parthenope, Bradinopyga geminate, Ischnura forcipata, Rhinocypha quadrimaculata, and Orthetrum sabina were evaluated against the 4th instar larvae of the den­gue vector mosquito, Aedes aegypti, under laboratory conditions. The consumption of the mosquito larvae was eval­uated at three water volume levels viz., 1 liter, 2 liter and 3 liter.Results: The number of Ae. aegypti larvae consumed varied significantly among the five species, and at different levels of water volume (P< 0.01. However, the interaction between odonate nymphs and the water volumes was statistically non-significant (P> 0.05. Ischnura forcipata consumed the highest number of Ae. aegypti larvae (n=56 followed by A. parthenope (n=47 and B. geminate (n=46. The number of larvae consumed was decreased with in­creasing search area or water volume, and the highest predation was observed at 1-liter water volume.Conclusion: The odonate nymphs could be a good source of biological agents for the management of the mosquitoes at larval stages. 

  11. Predicting the Start of the Aedes albopictus (Diptera: Culicidae) Female Adult Biting Season Using the Spring Temperature in Japan.

    Science.gov (United States)

    Komagata, Osamu; Higa, Yukiko; Muto, Atsushi; Hirabayashi, Kimio; Yoshida, Masahiro; Sato, Takashi; Nihei, Naoko; Sawabe, Kyoko; Kobayashi, Mutsuo

    2017-11-07

    Aedes albopictus (Skuse) (Diptera: Culicidae) is distributed widely and is common in much of Japan. In Japan, female adults begin to bite in between April and June, except in the southern subtropics where the mosquito has no dormant period. It is difficult to estimate the first Ae. albopictus biting day because it varies annually depending on the location. Over several years, we surveyed the mosquitoes at different locations that covered a range of warmer to cooler areas of Japan. We found an association between the timing of first biting day by Ae. albopictus and spring temperature. In spring months, the strongest correlation was found with mean April temperatures, followed by March. Based on these data, it may, therefore, be possible to apply a simple formula to predict the timing of the first biting day at various geographical locations in Japan. Forecasting maps were created using a simple prediction formula. We found that the first biting day for Ae. albopictus changed depending on early spring temperatures for each year. There was an approximate 20-d difference in first biting day between years with warmer and cooler springs. This prediction model will provide useful insight for planning and practice of Ae. albopictus control programs, targeting larvae and adults, in temperate regions globally. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  12. Changes in the fat body during the post-embryonic development of the predator Toxorhynchites theobaldi (Dyar & Knab) (Diptera: Culicidae).

    Science.gov (United States)

    Pascini, T V; Albeny, D S; Ramalho-Ortigão, M; Vilela, E F; Serrão, J E; Martins, G F

    2011-01-01

    Several studies have focused on understanding the biochemistry and morphology of the fat body of the hematophagous mosquito Aedes aegypti (L.) (Diptera: Culicidae). In contrast, few studies, if any, have focused on morphological characters of the fat body in other mosquitoes, especially non-hematophagous taxa such as the culicid Toxorhynchites. Larvae of Toxorhynchites prey upon the larvae of other mosquito species and are used in vector mosquito control. We investigated aspects of the fat body trophocytes, including the morphometric analyses of the lipid droplets, protein granules and nuclei, during Toxorhynchites theobaldi (Dyar & Knab) post-embryonic development. Following the body weight increase from larval stage L2 to L4, the size of lipid droplets within the trophocytes also increase, and are likely the result of lipogenesis. Lipid droplets decrease in size during L4 to the female pupal stage and increase once again during the period from newly-emerged to mature adult females. Protein granules are observed for the first time in female pupae, and their appearance might be related to protein storage during metamorphosis. The size of the nucleus of trophocytes also increases during larval development, followed by a decrease during metamorphosis and an additional increase as adult female ages. In conclusion, the morphology of the fat body of T. theobaldi changes according to the developmental stage. Our study provides for the first time important insights into T. theobaldi fat body development and contributes to understand this species biology.

  13. Biological activity of selected Lamiaceae and Zingiberaceae plant essential oils against the dengue vector Aedes aegypti L. (Diptera: Culicidae).

    Science.gov (United States)

    Kalaivani, Kandaswamy; Senthil-Nathan, Sengottayan; Murugesan, Arunachalam Ganesan

    2012-03-01

    The larvicidal activity of hydrodistillate extracts from Mentha piperita L. Ocimum basilicum L. Curcuma longa L. and Zingiber officinale L. were investigated against the dengue vector Aedes aegypti L. (Diptera: Culicidae).The results indicated that the mortality rates at 80, 100, 200 and 400 ppm of M. piperita, Z. officinale, C. longa and O. basilicum concentrations were highest amongst all concentrations of the crude extracts tested against all the larval instars and pupae of A. aegypti. Result of log probit analysis (at 95% confidence level) revealed that lethal concentration LC₅₀ and LC₉₀ values were 47.54 and 86.54 ppm for M. piperita, 40.5 and 85.53 ppm for Z. officinale, 115.6 and 193.3 ppm for C. longa and 148.5 and 325.7 ppm for O. basilicum, respectively. All of the tested oils proved to have strong larvicidal activity (doses from 5 to 350 ppm) against A. aegypti fourth instars, with the most potent oil being M. piperita extract, followed by Z. officinale, C. longa and O. basilicum. In general, early instars were more susceptible than the late instars and pupae. The results achieved suggest that, in addition to their medicinal activities, Lamiaceae and Zingiberaceae plant extracts may also serve as a natural larvicidal agent.

  14. Larvicidal and repellent activity of Hyptis suaveolens (Lamiaceae) essential oil against the mosquito Aedes albopictus Skuse (Diptera: Culicidae).

    Science.gov (United States)

    Conti, Barbara; Benelli, Giovanni; Flamini, Guido; Cioni, Pier Luigi; Profeti, Raffaele; Ceccarini, Lucia; Macchia, Mario; Canale, Angelo

    2012-05-01

    Lamiaceae have traditionally been used in developing countries for their insecticidal and repellent properties against several insect species. In our research, the essential oil (EO) extracted from fresh leaves of Hyptis suaveolens (Lamiaceae), and its main constituents were evaluated for larvicidal and repellent activity against the Asian tiger mosquito, Aedes albopictus Skuse (Diptera: Culicidae), currently the most invasive mosquito worldwide. H. suaveolens EO had insecticidal activity against A. albopictus larvae and mortality was dosage dependent. At the highest dosages of 450 and 400 ppm, there were no significant differences on larval mortality, as mortality ranged between 98.33% and 93.33%, respectively. At dosages ranging from 250 to 350 ppm, mortality rates were lower and not significantly different from each other. Terpinolene was found to be the most effective pure compound. Efficacy protection from H. suaveolens EO, at dosages ranging from 0.03748 to 0.7496 μg cm(-2) of skin, was evaluated during 150 min of observation. Results indicated that this EO had a significant repellent activity (RD(50) = 0.00035 μg cm(-2); RD(90) = 0.00048 μg cm(-2)), with differences in repellency rates, as a function of both concentration and observation time. Protection time ranged from 16 to 135 min. These results clearly evidenced that the larvicidal and repellent activity of H. suaveolens EO could be used for the development of new and safer products against A. albopictus.

  15. Efficacy of pyriproxyfen-treated nets in sterilizing and shortening the longevity of Anopheles gambiae (Diptera: Culicidae).

    Science.gov (United States)

    Ohashi, Kazunori; Nakada, Kazuhide; Ishiwatari, Takao; Miyaguchi, Jun'ichi; Shono, Yoshinori; Lucas, John R; Mito, Nobuaki

    2012-09-01

    Pyrethroid-resistant malaria vectors have become a serious threat for malaria control, and bed nets that reduce the development of resistance are urgently needed. Here, we tested the effects of bed nets treated with the insect growth regulator pyriproxyfen against adult female Anopheles gambiae Giles (Diptera: Culicidae) under laboratory conditions. Noninsecticidal nets made of 195 denier monofilament polyethylene with a mesh size of 75 holes per square inch (equivalent to the Olyset Net) were dipped in a 0.1, 0.01, or 0.001% (wt:vol) alcohol solution of pyriproxyfen and dried overnight. Adult females of an insecticide-susceptible An. gambiae strain were exposed to treated and untreated nets before and after a bloodmeal. Bioassays showed that females were completely sterilized after exposure to 0.1% (35 mg [AI]/m2) and 0.01% pyriproxyfen-treated nets both before and after a bloodmeal. In addition, adult longevity decreased after exposure to the pyriproxyfen-treated nets in a concentration-dependent manner. The sterilizing and life-shortening effects of pyriproxyfen on the vector mosquito indicate that the combined use of pyriproxyfen and pyrethroids on bed nets has the potential to provide better malaria control and prevent the further development of pyrethroid resistance in malaria vectors.

  16. Morphometric studies on Culex quinquefasciatus and Mansonia ...

    African Journals Online (AJOL)

    Morphological variation in Glossina pal- lidipes Austen (Diptera: Glossinidae) over its geographical range. Nigerian Journal of. Entomology 15, 122-135. Amusan, A.A.S. (2004) Distribution of mosquitoes. (Diptera:Culicidae) and disease transmis- sion patterns in Ogun State., Ph D Thesis,. University of Agriculture, Abeokuta ...

  17. Temporal patterns of abundance of Aedes aegypti and Aedes albopictus (Diptera: Culicidae and mitochondrial DNA analysis of Ae. albopictus in the Central African Republic.

    Directory of Open Access Journals (Sweden)

    Basile Kamgang

    Full Text Available The invasive Asian tiger mosquito Aedes albopictus (Diptera: Culicidae was first reported in central Africa in 2000, in Cameroon, with the indigenous mosquito species Ae. aegypti (Diptera: Culicidae. Today, this invasive species is present in almost all countries of the region, including the Central African Republic (CAR, where it was first recorded in 2009. As invasive species of mosquitoes can affect the distribution of native species, resulting in new patterns of vectors and concomitant risk for disease, we undertook a comparative study early and late in the wet season in the capital and the main cities of CAR to document infestation and the ecological preferences of the two species. In addition, we determined the probable geographical origin of invasive populations of Ae. albopictus with two mitochondrial DNA genes, COI and ND5. Analysis revealed that Ae. aegypti was more abundant earlier in the wet season and Ae. albopictus in the late wet season. Used tyres were the most heavily colonized productive larval habitats for both species in both seasons. The invasive species Ae. albopictus predominated over the resident species at all sites in which the two species were sympatric. Mitochondrial DNA analysis revealed broad low genetic diversity, confirming recent introduction of Ae. albopictus in CAR. Phylogeographical analysis based on COI polymorphism indicated that the Ae. albopictus haplotype in the CAR population segregated into two lineages, suggesting multiple sources of Ae. albopictus. These data may have important implications for vector control strategies in central Africa.

  18. Temporal patterns of abundance of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) and mitochondrial DNA analysis of Ae. albopictus in the Central African Republic.

    Science.gov (United States)

    Kamgang, Basile; Ngoagouni, Carine; Manirakiza, Alexandre; Nakouné, Emmanuel; Paupy, Christophe; Kazanji, Mirdad

    2013-01-01

    The invasive Asian tiger mosquito Aedes albopictus (Diptera: Culicidae) was first reported in central Africa in 2000, in Cameroon, with the indigenous mosquito species Ae. aegypti (Diptera: Culicidae). Today, this invasive species is present in almost all countries of the region, including the Central African Republic (CAR), where it was first recorded in 2009. As invasive species of mosquitoes can affect the distribution of native species, resulting in new patterns of vectors and concomitant risk for disease, we undertook a comparative study early and late in the wet season in the capital and the main cities of CAR to document infestation and the ecological preferences of the two species. In addition, we determined the probable geographical origin of invasive populations of Ae. albopictus with two mitochondrial DNA genes, COI and ND5. Analysis revealed that Ae. aegypti was more abundant earlier in the wet season and Ae. albopictus in the late wet season. Used tyres were the most heavily colonized productive larval habitats for both species in both seasons. The invasive species Ae. albopictus predominated over the resident species at all sites in which the two species were sympatric. Mitochondrial DNA analysis revealed broad low genetic diversity, confirming recent introduction of Ae. albopictus in CAR. Phylogeographical analysis based on COI polymorphism indicated that the Ae. albopictus haplotype in the CAR population segregated into two lineages, suggesting multiple sources of Ae. albopictus. These data may have important implications for vector control strategies in central Africa.

  19. Nuevos registros y distribución de mosquitos de la Argentina (Diptera: Culicidae New records and distribution of mosquitoes from Argentina (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Gustavo C. Rossi

    2006-12-01

    Full Text Available Se presentan 21 nuevos registros de especies y se amplía la distribución de otras 12 especies de los géneros Anopheles Meigen, Coquillettidia Dyar, Culex L., Haemagogus Williston, Ochlerotatus Lynch Arribalzaga, Onirion Harbach y Peyton, Orthopodomyia Theobald, Psorophora Robineau-Desvoidy, Sabethes Robineau-Desvoidy, Stegomyia Theobald, Toxorhynchites Theobald. Se incluyen comentarios y cambios de estatus para especies de Howardina Theobald, Ochlerotatus y Lutzia (Theobald. Actualmente, en la Argentina se hallan presentes 226 especies distribuidas en 23 géneros.Twenty one new records and 12 new distributional records of species of the genus Anopheles Meigen, Coquillettidia Dyar, Culex L., Haemagogus Williston, Ochlerotatus Lynch Arribalzaga, Onirion Harbach & Peyton, Orthopodomyia Theobald, Psorophora Robineau-Desvoidy, Sabethes Robineau-Desvoidy, Stegomyia Theobald, Toxorhynchites Theobald are reported. Comments and changes in the status of species of Howardina Theobald, Ochelrotatus and Lutzia Theobald are included. Currently, in Argentina are present 226 species distributed in 23 genera.

  20. First record of Orthopodomyia pulcripalpis (Rondani, 1872) (Diptera: Culicidae) in Austria.

    Science.gov (United States)

    Zittra, Carina; Obwaller, Adelheid G; Wimmer, Victoria; Berer, Dominik; Eigner, Barbara; Fuehrer, Hans-Peter

    2017-06-01

    During a three-year mosquito monitoring from 2014 to 2016, the strictly ornithophilic, originally Mediterranean species Orthopodomyia pulcripalpis (Rondani, 1872) was collected as single specimen for the first time in Austria in the district of Penzing in Vienna. Morphological species determination was confirmed by analysis of the mitochondrial cytochrome c oxidase subunit I gene. We thus not only confirm the existence of another mosquito species in Austria, but also add a new genus to the Austrian Culicidae taxa list.

  1. Diversity and abundance of mosquitoes (Diptera:Culicidae) in an urban park: larval habitats and temporal variation.

    Science.gov (United States)

    Medeiros-Sousa, Antônio R; Ceretti-Júnior, Walter; de Carvalho, Gabriela C; Nardi, Marcello S; Araujo, Alessandra B; Vendrami, Daniel P; Marrelli, Mauro T

    2015-10-01

    Urban parks are areas designated for human recreation but also serve as shelter and refuge for populations of several species of native fauna, both migratory and introduced. In Brazil, the effect of annual climate variations on Aedes aegypti and dengue epidemics in large cities like São Paulo is well known, but little is known about how such variations can affect the diversity of mosquito vectors in urban parks and the risk of disease transmission by these vectors. This study investigates the influence of larval habitats and seasonal factors on the diversity and abundance of Culicidae fauna in Anhanguera Park, one of the largest remaining green areas in the city of São Paulo. Species composition and richness and larval habitats were identified. Seasonality (cold-dry and hot-rainy periods) and year were considered as explanatory variables and the models selection approach was developed to investigate the relationship of these variables with mosquito diversity and abundance. A total of 11,036 specimens from 57 taxa distributed in 13 genera were collected. Culex nigripalpus, Cx. quinquefasciatus and Aedes albopictus were the most abundant species. Bamboo internodes and artificial breeding sites showed higher abundance, while ponds and puddles showed greater richness. Significant relationships were observed between abundance and seasonality, with a notable increase in the mosquitos abundance in the warm-rainy periods. The Shannon and Berger-Parker indices were related with interaction between seasonality and year, however separately these predictors showed no relationship with ones. The increased abundance of mosquitoes in warm-rainy months and the fact that some of the species are epidemiologically important increase not only the risk of pathogen transmission to people who frequent urban parks but also the nuisance represented by insect bites. The findings of this study highlight the importance of knowledge of culicid ecology in green areas in urban environments

  2. Conteúdo dos criadouros larvais e comportamento de adultos de Toxorhynchites (Lynchiella haemorrhoidalis haemorrhoidalis (Fabricius (Diptera, Culicidae numa floresta de terra-firme da Amazônia central Larval breeding site contents and adult behavior of toxorhynchites (Lynchiella haemorrhoidalis haemorrhoidalis (Fabricius (Diptera, Culicidae in an upland forest of the central amazon

    Directory of Open Access Journals (Sweden)

    Rosa Sá Gomes Hutchings

    1995-01-01

    Full Text Available The natural breeding sites of Toxorhynchites (Lynchiella haemorrhoidalis haemorihoidalis (Fabricius, 1794, in two study areas, were sampled monthly, during a period of one year, in an upland "terra-firme" forest of the Central Amazon. These natural breeding sites, consisting of water filled palm bracts on the ground, contained invertobrates and vertebrates along with palm inflorescences, leaves and twigs. The inhabitants of the non-submersed area of the bracts include Diplopoda, Acarina, Araneae, Pseudoscorpiones, Isopoda, Blattodea, Coleoptera (Carabidae, Curculionidae, Scolytidae, Staphilinidae. Collembola, Dermaptera, Diptera (Cecidomyidae, Drosophilidae, Mycetophilidae, Tipulidae, Hemiptera, Hymenoptera and Trichoptera. The submersed areas of the bracts were inhabited by Oligochaeta, Coleoptera (Dysticidae, Helodidae, Histeridae, Hydrophilidae, Limnebiidae, Diptera (Ceratopogonidae, Chirononiidae, Culicidae, Psychodidae, Stratiomyidae, Syrphidae. Odonata, along with immature Dendrobatidae e Hylidae. The ovipositing, resting and feeding behaviors of T. h. haemorrhoidalis adults are described.

  3. Biochemical studies of insecticide resistance in Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus (Diptera: Culicidae) in Thailand.

    Science.gov (United States)

    Pethuan, S; Jirakanjanakit, N; Saengtharatip, S; Chareonviriyaphap, T; Kaewpa, D; Rongnoparut, P

    2007-06-01

    Biochemical analysis was performed on field caught Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus (Diptera: Culicidae) mosquitoes to determine activities of enzymes including mixed function oxidases (MFO), nonspecific esterases (alpha- and beta-), glutathione-S-transferases (GST), and insensitive acetylcholinesterase (AChE). Biochemical tests were performed on F1 generation of Ae. aegypti field caught mosquitoes, while in Ae. albopictus F2 progenies were used. Twenty-six samples of Ae. aegypti mosquito were collected from areas across different parts of Thailand including Bangkok (central), and the provinces of Chiang Rai (north), Nakhon Sawan (north-central), Nakhon Ratchasrima (northeast), Chonburi (east), Chanthaburi (east), and Songkhla (south). Eight wild caught samples of Ae. albopictus were from Songkhla, Nakhon Sawan, Nakhon Ratchasrima and Kanchanaburi (west) provinces. The susceptibility to pyrethroids (deltamethrin, permethrin), organophosphate (fenitrothion) and carbamate (propoxur) insecticides were revealed in these samples. The biochemical test results were compared with those of the susceptible Bora (French Polynesia) strain. There was significant enhancement of MFO in pyrethroid resistant Ae. aegypti samples, except those from Songkhla and Hauykwang district in Bangkok. Biochemical assay results suggested that nonspecific esterases conferred fenitrothion resistance in Ae. aegypti in Nakhon Sawan, while insensitive AChE and/or nonspecific esterases could play role in fenitrothion resistance in Nakhon Ratchasrima. There was no consistent association of GST with pyrethroid resistance in Ae. aegypti. Low enzyme activities found in Ae. aegypti in Songkhla and in Ae. albopictus corresponded to their insecticide susceptibility status. The increased enzyme activity in field samples reflecting local history of insecticide employment was discussed.

  4. Parathelohania iranica sp. nov. (Microsporidia: Amblyosporidae) infecting malaria mosquito Anopheles superpictus (Diptera: Culicidae): Ultrastructure and molecular characterization.

    Science.gov (United States)

    Omrani, Seyed-Mohammad; Moosavi, Seyedeh-Fatemeh; Farrokhi, Effat

    2017-06-01

    Microsporidia are common pathogens of insects and sometimes are considered as a candidate in the biological control of mosquitoes. Recently a microsporidium infection was discovered in Anopheles superpictus (Diptera: Culicidae) larvae, in Iran. The responsible agent belonged to the genus Parathelohania (Microsporidia: Amblyosporidae). This study has been carried out to identify its identity at the species level. Fresh infected larvae were collected from the type locality, Kiar district, in Chahar Mahal and Bakhtiari province, at the central western of Iran. Superficial and the internal ultrastructure of the recovered spores were explored by scanning and transmission electron microscopy, respectively. Molecular techniques were also employed to amplify parts of its ssu rDNA. The obtained data were compared with the available information of congener species and other closely related microsporidia to elucidate evolutionary relationship. A small apical depression and two posterolateral ridges extending backward from a pear shaped anterior body mass were notable under scanning electron microscopy. Transmission electron microscopy revealed 2 broad and 3-4 narrow coils in the either side of spores, respectively. The sequence of a 1062 nucleotide fragment of ssu rDNA was determined by means of PCR technique. This study indicates that the microsporidium infecting An. superpictus differs from other previously described species in the genus Parathelohania. It means that the microsporidium infecting An. superpictus is a new species and hereby it is called Parathelohania iranica. Further work is necessary to clarify its life cycle and probable value in the biological control of mosquitoes. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Mosquitos (Diptera: Culicidae) de los parques naturales de la Comunidad Valenciana

    OpenAIRE

    Bernués Bañeres, Alberto

    2013-01-01

    La familia Culicidae incluye algunas de las especies de dípteros más relevantes en el ámbito de la Salud Pública, no solo por las molestias que son capaces de causar debido a su tipo de alimentación hematófaga, sino por su capacidad para actuar como vectores de enfermedades de afección humana. Por este motivo, los mosquitos han sido, desde siempre, una de las dianas predilectas en los programas de control establecidos para la regulación de sus poblaciones y, por tanto, como medida profiláctic...

  6. Especificidade da armadilha Adultrap para capturar fêmeas de Aedes aegypti (Diptera: Culicidae Specificity of the Adultrap for capturing females of Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Almério de Castro Gomes

    2007-04-01

    Full Text Available A Adultrap é uma nova armadilha feita para capturar fêmeas de Aedes aegypti. Foram realizados testes para avaliar sua especificidade tendo como referência a técnica da aspiração da espécie em abrigos artificiais. A Adultrap ficou exposta por 24 horas no intradomicílio e peridomicílio de 120 casas sorteadas em dois bairros da Cidade de Foz do Iguaçu, Estado do Paraná. O teste estatístico foi o modelo log-linear de Poisson. O resultado foi a captura de 726 mosquitos Culicidae, dos quais 80 eram Aedes aegypti. A Adultrap capturou apenas fêmeas desta espécie, enquanto o aspirador os dois sexos de Aedes aegypti e mais cinco outras espécies. A Adultrap capturou Aedes aegypti dentro e fora das casas, mas a análise indicou que no peridomicílio a armadilha capturou significantemente mais fêmeas do que a aspiração. Também, ficou evidenciada a sensibilidade da Adultrap para detectar Aedes aegypti em situação de baixa freqüência.The Adultrap is a new trap built for capturing females of Aedes aegypti. Tests were carried out to evaluate the specificity of this trap in comparison with the technique of aspiration of specimens in artificial shelters. Adultraps were kept for 24 hours inside and outside 120 randomly selected homes in two districts of the city of Foz do Iguaçú, State of Paraná. The statistical test was Poisson’s log-linear model. The result was 726 mosquitoes captured, of which 80 were Aedes aegypti. The Adultrap captured only females of this species, while the aspiration method captured both sexes of Aedes aegypti and another five species. The Adultrap captured Aedes aegypti inside and outside the homes, but the analysis indicated that, outside the homes, this trap captured significantly more females than aspiration did. The sensitivity of the Adultrap for detecting females of Aedes aegypti in low-frequency situations was also demonstrated.

  7. The Anopheles (Anopheles) Crucians Subgroup in the United States (Diptera: Culicidae)

    Science.gov (United States)

    1976-01-01

    Forattini, 0. P. 1962. Entomologica medica. Vol. 1: Parte geral, Diptera, Anophelini. Departamento de Parasitologia , Sao Paulo, Brazil. 662 p. Freeborn, S...Ross, E. S. and H. R. Roberts. 194%. Mosquito atlas : Part I. The nearctic Anophe Zes , important malaria vectors of the Americas and Aedes aegypti

  8. Imaturos de Culicidae (Diptera encontrados em recipientes instalados em mata residual no munícipio de Londrina, Paraná, Brasil Immature specimens of Culicidae (Diptera found in installed recipients in forest fragments in the Londrina, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    João A. C. Zequi

    2005-09-01

    Full Text Available Fragmentos de mata na área urbana ou periurbana podem ser locais favoráveis a procriação de Culicidae. Esse trabalho teve como objetivo levantar as espécies de culicídeos que utilizam criadouros artificiais, suas coexistência e as flutuações populacionais em uma reserva de mata localizada em Londrina - PR. Realizou-se coletas quinzenais de outubro de 1995 a setembro de 1996 em pneus e internódios de bambu armadilha que foram instalados ao nível do solo e outros internódios instalados a 2 m de altura. Coletou-se 12.656 espécimes, pertencentes a cinco gêneros e 11 espécies. As espécies mais abundantes nos criadouros foram Limatus durham Theobald, 1901, Culex eduardoi Casal & Garcia, 1968, Aedes terrens (Walker, 1856, Culex quinquefasciatus Say, 1823 e Aedes albopictus (Skuse, 1894. O maior número de indivíduos foi coletado em pneus, sendo que Limatus durham e Aedes terrens, apresentaram preferência nesse criadouro. A presença de Aedes aegypti (Linnaeus, 1762, Aedes albopictus e Haemagogus leucocelaenus (Dyar & Shannon, 1924 em diferentes coletas indica que esse tipo de ambiente não deve ser ignorado nas ações de controle de vetores, merecendo constante monitoramento.Forest fragments in an urban area were found to be a situable site for Culicidae breeding. This research aims to inventory the Culicidae species that use artificial breeding sites, their coexistence, and the population variation in a fragment forest in the Londrina City, Paraná State. Biweekly collecting efforts were performed from October 1995 to September 1996 using tires and bamboo internodes traps installed at a ground level and bamboo internodes traps at two 2 m height. A total of 12,656 culicid specimens belonging to five genus and 11 species were collected. The most abundant species in those artificial breeding sites were Limatus durhami Theobald, 1901, Culex eduardoi Couple & Garcia, 1968, Aedes terrens (Walker, 1856, Culex quinquefasciatus Say, 1823 and

  9. Molecular phylogeny and evolutionary relationships among mosquitoes (Diptera: Culicidae) from the northeastern United States based on small subunit ribosomal DNA (18S rDNA) sequences.

    Science.gov (United States)

    Shepard, John J; Andreadis, Theodore G; Vossbrinck, Charles R

    2006-05-01

    The phylogenetic relationships of Culicidae native to the northeastern United States were investigated by analyzing small subunit ribosomal DNA (18S rDNA) sequences obtained from 39 species representing nine genera. Molecular phylogenies were consistent with traditional classifications based on morphological characters except for the placements of Psorophora Robineau-Desvoidy and Uranotaenia Lynch Arribalzaga. In our analyses, 1) Anopheles Meigen was strongly supported as the sister taxon to the remaining Culicidae; 2) Toxorhynchites Theobald was represented as a distinct monophyletic sister group to the Culicinae; 3) Psorophora formed a basal clade to Culiseta Felt, Coquillettidia Dyar, and Culex L. but also was shown as a sister taxon to Aedes Meigen and Ochlerotatus Lynch Arribalzaga; 4) Coquillettidia perturbans (Walker) seems to be a sister group to Culiseta; 5) placement of Uranotaenia was inconclusive and seemed to be either a sister group to the Aedes and Ochlerotatus or a basal taxon to all other culicines; and 6) Aedes and Ochlerotatus formed two separate and distinct clades, providing phylogenetic data consistent with the recent elevation of Ochlerotatus to the generic level as proposed by Reinert (2000). The utility of 18S rDNA for evaluating phylogenetic and evolutionary relationships among mosquito taxa was demonstrated at the genus and species levels. To our knowledge, this study represents the first molecular-based phylogenetic study of mosquito species occurring within this geographic region of North America and contains the largest number of species that have been examined among the genera Aedes and Ochlerotatus.

  10. Repellency effect of forty-one essential oils against Aedes, Anopheles, and Culex mosquitoes.

    Science.gov (United States)

    Amer, Abdelkrim; Mehlhorn, Heinz

    2006-09-01

    Since ancient times, plant products were used in various aspects. However, their use against pests decreased when chemical products became developed. Recently, concerns increased with respect to public health and environmental security requiring detection of natural products that may be used against insect pests. In this study, 41 plant extracts and 11 oil mixtures were evaluated against the yellow fever mosquito, Aedes aegypti (Linnaeus), the malaria vector, Anopheles stephensi (Liston), and the filariasis and encephalitis vector, Culex quinquefasciatus (Say) (Diptera: Culicidae) using the skin of human volunteers to find out the protection time and repellency. The five most effective oils were those of Litsea (Litsea cubeba), Cajeput (Melaleuca leucadendron), Niaouli (Melaleuca quinquenervia), Violet (Viola odorata), and Catnip (Nepeta cataria), which induced a protection time of 8 h at the maximum and a 100% repellency against all three species. This effect needs, however, a peculiar formulation to fix them on the human skin.

  11. Permethrin and malathion LD90values for Culex quinquefasciatus vary with topical application site.

    Science.gov (United States)

    Aldridge, R L; Kaufman, P E; Bloomquist, J R; Gezan, S A; Linthicum, K J

    2017-09-01

    Prior research in multiple insect species has demonstrated that insecticide-induced mortality varies according to the body region exposed on the insect. This variation has been demonstrated in Culex quinquefasciatus Say (Diptera: Culicidae), but has not been quantified using dose-response curves. Applications of technical permethrin or malathion to one of three body regions on Cx. quinquefasciatus resulted in dose-response curves that were not equivalent to one another. The generated LD 90 values and curves for each body region were compared with previously reported LD values for analogous sites in several mosquito species, specifically the mesothorax. Based on the present results, the permethrin and malathion LD 50 and LD 90 concentrations required for droplets impinging on the abdomen and mesothorax of Cx. quinquefasciatus when applied through ground-based spray systems utilized by mosquito control programmes were calculated. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  12. Ecology of Anopheline (Diptera, Culicidae, malaria vectors around the Serra da Mesa Reservoir, State of Goiás, Brazil: 1 - Frequency and climatic factors

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    Anthony Érico Guimarães

    Full Text Available The ecology of anopheline species (Diptera, Culicidae was studied in the vicinity of the Serra da Mesa Reservoir, State of Goiás, Brazil. Climatic factors and frequency of anopheline populations were analyzed. Bimonthly human-bait and Shannon trap captures were conducted for 36 consecutive months (January 1997 through December 1999. A total of 5,205 adult anophelines belonging to five species were collected. Anopheles darlingi was the most frequently collected anopheline (61.4%, followed by An. albitarsis s.l. (35.4%, An. triannulatus. (2.5%, An. oswaldoi (0.4%, and An. evansae (0.2%. The water level and vegetation along the banks of the reservoir were crucial to the frequency of the various anopheline species. Climatic factors had a secondary influence. The reservoir's water-level stability, increased frequency of An. darlingi, and the arrival of gold prospectors were responsible for the increase in malaria cases.

  13. Primeiro registro do gênero Toxorhynchites Theobald (Diptera, Culicidae em Mata Atlântica, Viçosa, Minas Gerais

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    Daniel Simões Albeny

    2010-04-01

    Full Text Available Durante os meses de março e abril de 2007 foi verificada a presença do gênero Toxorhynchites (Diptera, Culicidae em fragmentos de Mata Atlântica no município de Viçosa, Minas Gerais, Brasil. No experimento foram utilizadas 500 armadilhas de oviposição. Registrando-se, pela primeira vez na região de Viçosa o gênero Toxorhynchites, sendo as espécies T. pusillus (Costa Lima, 193 1 e T. theobaldi (Dyar & Knab, 1906 encontradas pela primeira vez no Estado de Minas Gerais. As espécies relatadas como primeiro registro e sua distribuição são citadas e discutidas.

  14. Morphological changes in the midgut of Aedes aegypti L. (Diptera: Culicidae) larvae following exposure to an Annona coriacea (Magnoliales: Annonaceae) extract.

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    Costa, M S; Pinheiro, D O; Serrão, J E; Pereira, M J B

    2012-08-01

    Bioinsecticides are important in the control of disease vectors, but data regarding their physiological effects on target insects are incomplete. This study describes morphological changes that occur in the midgut of third instar Aedes aegypti L. (Diptera: Culicidae) following treatment with a methanolic extract of Annona coriacea (Magnoliales: Annonaceae). Dissected midguts were subdivided into anterior and posterior regions and analyzed by light and scanning electron microscopy. Insects exposed to the extract displayed intense, destructive cytoplasmic vacuolization in columnar and regenerative midgut cells. The apical surfaces of columnar cells exhibited cytoplasmic protrusions oriented toward the lumen, suggesting that these cells could be involved in apocrine secretory processes and/or apoptosis. We report that A. coriacea extracts induced morphological alterations in the midgut of A. aegypti midgut larvae, supporting the use of plant extracts for control of the dengue vector.

  15. Biocidal activity of three wood essential oils against Ixodes scapularis (Acari: Ixodidae), Xenopsylla cheopis (Siphonaptera: Pulicidae), and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Dolan, Marc C; Dietrich, Gabrielle; Panella, Nicholas A; Montenieri, John A; Karchesy, Joseph J

    2007-04-01

    The biocidal activity of three steam distilled wood essential oils-incense cedar, Calocedrus decurrens (Torr.) Florin; Port-Orford-cedar, Chamaecyparis lawsoniana (A. Murr.) Parl.; and western juniper, Juniperus occidentalis (Hook)--were evaluated against adult Aedes aegypti (L.) (Diptera: Culicidae) and Xenopsylla cheopis (Rothchild) (Siphonaptera: Pulicidae) and nymphal Ixodes scapularis Say (Acari: Ixodidae). In vitro laboratory bioassays were conducted to establish baseline dose-mortality data through 24 h. Incense cedar heartwood was the most toxic to all three vector species followed in order of activity by western juniper and Port-Orford-cedar based on LC50 and LC90 values. Ae. aegypti were substantially more susceptible to the oils than either I. scapularis or X. cheopis.

  16. Morphological abnormalities in species of the quadrimaculatus complex of Anopheles (Diptera: Culicidae).

    Science.gov (United States)

    Reinert, J F

    1999-03-01

    This report provides results of the first detailed examination of morphological abnormalities occurring in adults, pupae, and 4th-instar larvae of a sibling species complex within the family Culicidae. Aberrant and/or anomalous setae or structures are reported, along with their frequency of occurrence, for the 5 sibling species (Anopheles diluvialis, Anopheles inundatus, Anopheles maverlius, Anopheles quadrimaculatus, and Anopheles smaragdinus) of the Quadrimaculatus Complex of Anopheles. A total of 21,684 specimens were examined. In the pupal stage, the presence of seta 11-II was the most common anomaly, whereas in the 4th-instar larva, branching of seta 2-C occurred most frequently. Abnormalities in the male genitalia usually involved the claspette or tergum IX. Other abnormalities in females, male genitalia, pupae, and 4th-instar larvae occurred infrequently.

  17. Urban mosquito species (Diptera: Culicidae of dengue endemic communities in the Greater Puntarenas area, Costa Rica

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    Olger Calderón-Arguedas

    2009-12-01

    Full Text Available Field studies were conducted to determine the mosquito species richness in the urban area of Greater Puntarenas in Costa Rica. Two cross-sectional entomological surveys were performed in seven localities of Puntarenas: one survey was performed during the wet season and the other during the dry season. The sections evaluated were determined by applying a stratified cluster sampling method using satellite imagery, and a sample of 26 cells (100x100m was selected for the study. The number of cells per locality was proportional to the area of each locality. The presence of mosquito larvae and pupae in water-filled artificial and natural containers was determined in each cell. Infestation was expressed as a diversity index per type of container (Ii. Eight types of larvae were identified (Aedes aegypti, Culex quinquefasciatus, Culex interrogator, Culex nigripalpus, Culex corniger, Culex tarsalis, Limatus durhamii and Toxorhynchites theobaldi and in two cases it was only possible to identify the genus (Culex sp. and Uranotaenia sp.. A. aegypti was the most common species followed by C. quinquefascitus. Diversity of wet environments can explain the co-occurrence of various culicid species in some localities. Although A. aegypti is the only documented disease vector in the area, C quinquefasciatus, C. nigripalpus, and the other species of Culex could be considered potential vectors of other pathogens. The presence and ecology of all mosquito species should be studied to optimize surveillance and prevention of dengue and to prevent the emergence of other mosquito-transmitted diseases. Rev. Biol. Trop. 57 (4: 1223-1234. Epub 2009 December 01.La riqueza de especies de mosquitos urbanos de la Gran Puntarenas (Puntarenas, Costa Rica fue evaluada por medio de análisis larvales. Dos encuestas entomológicas fueron realizadas en siete localidades de la Gran Puntarenas durante un año. Una de las encuestas fue realizada en la estación seca y la otra se llevó a

  18. Immature mosquitoes (Diptera: Culicidae in a eutrophic landfill tank from State of Rio de Janeiro, Brazil

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    Jeronimo Alencar

    2013-12-01

    Full Text Available Introduction To determine the faunal composition of immature culicids inhabiting a percolation tank in the landfill of Sapucaia, State of Rio de Janeiro, Brazil, immature mosquitoes were collected over a two-day period during the third weeks of April, August and October 2011. Results The species found were Culex usquatus, Lutzia bigoti, Anopheles argyritarsis and Limatus durhamii. This study is the first to report the colonization of eutrophic breeding sites by these species. Conclusions The oviposition behavior observed in this study suggests a secondary adaptation or change in habit to select eutrophic environments during the developmental stages of the observed species.

  19. Larvicidal efficiency of the mushroom Amanitamuscaria (Agaricales, Amanitaceae) against the mosquito Culexquinquefasciatus (Diptera, Culicidae).

    Science.gov (United States)

    Cárcamo, Marcial Corrêa; Carapeto, Luiz Paiva; Duarte, Jucelio Peter; Bernardi, Eduardo; Ribeiro, Paulo Bretanha

    2016-02-01

    We report the larvicidal activity of two formulations from Amanita muscariaagainst Culex quinquefasciatus, as well as the viability of the aqueous extract after storage. METHODS The larvicidal activity of aqueous extract and powder from A. muscaria, and the viability of the aqueous extract after storage, were evaluated. RESULTS The aqueous extract caused larval deaths, which varied from 16.4% to 88.4%. The efficiency of the powder varied from 29.2% to 82.8%. Storage did not interfere with the larvicidal efficiency of the aqueous extract of A. muscaria. CONCLUSIONS These results show the potential of A. muscariato control C. quinquefasciatus.

  20. Larvicidal efficiency of the mushroom Amanitamuscaria (Agaricales, Amanitaceae against the mosquito Culexquinquefasciatus (Diptera, Culicidae

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    Marcial Corrêa Cárcamo

    2016-02-01

    Full Text Available Abstract: INTRODUCTION: We report the larvicidal activity of two formulations from Amanita muscariaagainst Culex quinquefasciatus, as well as the viability of the aqueous extract after storage. METHODS The larvicidal activity of aqueous extract and powder from A. muscaria, and the viability of the aqueous extract after storage, were evaluated. RESULTS The aqueous extract caused larval deaths, which varied from 16.4% to 88.4%. The efficiency of the powder varied from 29.2% to 82.8%. Storage did not interfere with the larvicidal efficiency of the aqueous extract of A. muscaria. CONCLUSIONS These results show the potential of A. muscariato control C. quinquefasciatus.

  1. New report on the bionomics of Coquillettidia venezuelensis in temporary breeding sites (Diptera: Culicidae

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    Jeronimo Alencar

    2011-04-01

    Full Text Available INTRODUCTION: Findings of immature forms of Coquillettidia venezuelensis in temporary breeding sites, without the presence of aquatic plants or other submerged plant tissue are reported. METHODS: A systematic scooping technique to collect specimens was used at the breeding site. RESULTS: Immature forms of Coquillettidia venezuelensis, Anopheles rangeli, An. evansae and Culex sp. were collected from areas of the hydroelectric power station of São Salvador, State of Goiás. CONCLUSIONS This is a novel finding relating to the bioecology of Cq. venezuelensis, a species of medical interest that has been found naturally infected with arboviruses, including Oropouche and West Nile virus.

  2. Nuevos registros y distribución de mosquitos de la Argentina (Diptera: Culicidae

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    Gustavo C. ROSSI

    2006-01-01

    Full Text Available Se presentan 21 nuevos registros de especies y se amplía la distribución de otras 12 especies de los géneros Anopheles Meigen, Coquillettidia Dyar, Culex L., Haemagogus Williston, Ochlerotatus Lynch Arribalzaga, Onirion Harbach y Peyton, Orthopodomyia Theobald, Psorophora Robineau-Desvoidy, Sabethes Robineau-Desvoidy, Stegomyia Theobald, Toxorhynchites Theobald. Se incluyen comentarios y cambios de estatus para especies de Howardina Theobald, Ochlerotatus y Lutzia (Theobald. Actualmente, en la Argentina se hallan presentes 226 especies distribuidas en 23 géneros.

  3. Mosquito (Diptera: Culicidae) repellency field tests of essential oils from plants traditionally used in Laos.

    Science.gov (United States)

    Vongsombath, Chanda; Pålsson, Katinka; Björk, Lars; Borg-Karlson, Anna-Karin; Jaenson, Thomas G T

    2012-11-01

    Essential oils of Hyptis suaveolens (Lamiaceae), Croton roxburghii (Euphorbiaceae), and Litsea cubeba (Lauraceae) were tested in the field near Vientiane city, Lao PDR, on humans for repellent activity against mosquitoes. Landing mosquitoes were collected and later identified. The most abundant mosquitoes captured belonged to the genera Armigeres, Culex, and Aedes. All the plant oils tested at concentrations of 1.7 microg/cm(2), 3.3 microg/cm(2), and 6.3 microg/cm(2) were significantly more mosquito repellent than the negative control. Croton oil was significantly repellent against mosquitoes of the three genera at the highest (6.3 microg/cm(2)) concentration tested. Litsea oil was significantly repellent against Armigeres at all (1.7 microg/cm(2), 3.3 microg/cm(2), and 6.3 microg/cm(2)) concentrations tested. Hyptis oil was significantly repellent against Armigeres at 3.3 microg/cm(2) and 6.3 microg/cm(2) and against Culex at 1.7 microg/cm(2) and 6.3 microg/cm(2). The oils were analyzed for chemical content of volatiles, mainly terpenes. Main constituents were beta-pinene, sabinene, and 1,8-cineol from oils of the green parts of H. suaveolens; alpha-pinene, beta-pinene, and alpha-phellandrene from fresh bark of C. roxburghii; and alpha-pinene, beta-phellandrene, sabinene, and 1,8-cineol from fresh fruits of L. cubeba.

  4. Preferencia de hospedadores de Culicidae (Diptera recolectados en el centro de la Argentina

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    Almirón Walter R.

    1995-01-01

    Full Text Available Con el propósito de estudiar la preferencia de hospedadores vertebrados por mosquitos hembras, durante 2 períodos octubre-abril (primavera-verano, se realizaron muestreos cada 15 días en Córdoba y Cosquín (Argentina. Se utilizaron trampas de latón con cebo animal: anfibios (sapos, aves (pollos, mamíferos (conejos y reptiles (tortugas. El 92,9% de los especímenes recolectados pertenecen al género Culex, mientras que un 7,0% corresponde a Aedes y el 0,02% restante a Psorophora ciliata, única especie que se capturó de ese género. En trampas con pollo se recolectó el mayor número de hembras (68,7%, siguiendo en orden las trampas con conejos (29,9%, con tortugas (0,8% y con sapos (0,5%, por lo tanto, la mayoría de los mosquitos entraron en las trampas con hospedadores homeotermos. Culex dolosus se alimentó sobre todos los cebos, mientras que Cx. acharistus, Cx. chidesteri y Cx. quinquefasciatus se alimentaron sobre pollos, conejos y tortugas; Ae. albifasciatus, Ae. scapularis, Cx. bidens y Cx. coronator lo hicieron sobre ambos hospedadores homeotermos; Cx. apicinus, Cx. maxi, Cx. saltanensis y Cx. spinosus se alimentaron solamente sobre pollos y Ps. ciliata sobre conejos.

  5. A list of mosquito species of the Brazilian State of Pernambuco, including the first report of Haemagogus janthinomys (Diptera: Culicidae, yellow fever vector and 14 other species (Diptera: Culicidae Lista de espécies de mosquitos do Estado de Pernambuco e primeiro relato de Haemagogus janthinomys (Diptera: Culicidae vetor de febre amarela silvestre e outras 14 espécies (Diptera: Culicidae

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    Nádia Consuelo Aragão

    2010-08-01

    Full Text Available INTRODUCTION: Besides mosquito species adapted to urban environments (Culex quinquefasciatus, Aedes aegypti and Aedes albopictus, only 15 species of Anopheles had been recorded in the State of Pernambuco. METHODS: Human-landing mosquitoes were collected in Dois Irmãos Park, in Recife. RESULTS: The first report for the state of Haemagogus janthinomys, an important vector of yellow fever virus, and 14 other species, including Trichoprosopon lampropus, a first reported for Brazil. CONCLUSIONS: The mosquito fauna in the area is diversified and has potential medical and veterinary importance.INTRODUÇÃO: Além de mosquitos adaptados ao ambiente urbano (Culex quinquefasciatus, Aedes aegypti e Ae. albopictus, apenas 15 espécies de Anopheles haviam sido relatadas no Estado de Pernambuco. MÉTODOS: Mosquitos que pousavam em humanos no Parque Dois Irmãos, em Recife foram coletados. RESULTADOS: Haemagogus janthinomys, importante vetor de vírus de febre amarela, e outras 14 espécies são relatadas pela primeira vez no estado, incluindo Trichoprosopon lampropus, relatado pela primeira vez no Brasil. CONCLUSÕES: A fauna de mosquitos na área é muito diversificada e tem potencial importância médica e veterinária.

  6. Spatial evaluation of larvae of Culicidae (Diptera from different breeding sites: application of a geospatial method and implications for vector control Avaliação espacial de formas larvais de Culicidae (Diptera em diferentes criadouros: aplicação de um método geoespacial e implicações para o controle de vetores

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    Rafael Piovezan

    2012-09-01

    Full Text Available Spatial evaluation of Culicidae (Diptera larvae from different breeding sites: application of a geospatial method and implications for vector control. This study investigates the spatial distribution of urban Culicidae and informs entomological monitoring of species that use artificial containers as larval habitats. Collections of mosquito larvae were conducted in the São Paulo State municipality of Santa Bárbara d' Oeste between 2004 and 2006 during house-to-house visits. A total of 1,891 samples and nine different species were sampled. Species distribution was assessed using the kriging statistical method by extrapolating municipal administrative divisions. The sampling method followed the norms of the municipal health services of the Ministry of Health and can thus be adopted by public health authorities in disease control and delimitation of risk areas. Moreover, this type of survey and analysis can be employed for entomological surveillance of urban vectors that use artificial containers as larval habitat.Avaliação espacial de formas larvais de Culicidae (Diptera em diferentes criadouros: aplicação de um método geoespacial e implicações para o controle de vetores. Este estudo investiga a distribuição espacial da fauna urbana e de Culicidae e informa o monitoramento entomológico de espécies que usam recipientes artificiais como habitat larval. Coletas de larvas de mosquitos foram realizadas no município paulista de Santa Bárbara d' Oeste entre os anos de 2004 e 2006, durante visitas casa-a-casa. Um total de 1.891 amostras foi considerado, com nove espécies diferentes coletadas. A distribuição das espécies foi avaliada através do método de krigagem estatística extrapolando as divisões administrativas do município. O método de coleta adotado no presente estudo está de acordo com os métodos sugeridos aos serviços de saúde municipais pelo Ministério da Saúde e pode, portanto, ser adotado pelas autoridades p

  7. Mosquitoes (Diptera: Culicidae) from crepuscular period in an Atlantic Forest area in Southern Brazil.

    Science.gov (United States)

    Orlandin, E; Santos, E B; Piovesan, M; Favretto, M A; Schneeberger, A H; Souza, V O; Muller, G A; Wagner, G

    2017-03-01

    Crepuscular period is one of the factors that may influence the biting activity of mosquitoes. Many of these insects have a peak activity in this period. The purpose of this study was to investigate the afternoon crepuscular activity of Culicidae in a remaining area of Atlantic Forest in western Santa Catarina, southern Brazil. Moreover, the possible influence of abiotic factors, the abundance and species richness were verified. In order to better analyze the influence of crepuscular period in specific composition and abundance of mosquitoes, the dusk was divided into three periods: pre-sunset, sunset and post-sunset. At the end of the study, nine hundred and eight four specimens distributed in 12 genera and 23 species were collected. Trichoprosopon pallidiventer (Lutz, 1905) (59.76%), Aedes crinifer (Theobald, 1903) (8.13%), Ae. scapularis (Rondani, 1848) (5.89%) were the most abundant species. Spring time presented the greatest abundance and species richness. During the study, among the three periods evaluated, pre-sunset had the greatest abundance and post-sunset the lowest. Pre-sunset and sunset had the greatest similarity between species. Regarding to the abiotic factors evaluated seven and 15 days before sampling, they did not present significant correlation for the three most abundant species. However, temperature had a positive correlation to these species. Moreover, the correlation between collected species and its possible role as vectors of etiological agents of diseases was discussed.

  8. [Mosquitoes (Diptera, Culicidae) and their medical importance for Portugal: challenges for the 21st century].

    Science.gov (United States)

    Gouveia de Almeida, A Paulo

    2011-01-01

    Mosquitoes are dipterous insects, responsible for the transmission of several pathogenic agents to humans, causing vector-borne diseases, such as malaria, lymphatic and other filariasis, and several arboviral diseases such as yellow fever and dengue. In this revision, Culicidae or mosquitoes are summarily characterized, as well as their bioecology, internal morphology, digestive and egg maturation physiology, and the main methods for their collection and control. The epidemiology of mosquito-borne diseases depends on parameters such as Vectorial efficiency, Vector competence and Vectorial capacity, the concepts of which are presented. Forty one species of mosquitoes have been detected so far in mainland Portugal. Malaria was endemic till 1959, yellow fever outbreaks were registered in the XIX century, and human cases of dirofilarisis and West Nile fever have been detected. In face of the current climate changes in course and the threat of the (re)-introduction of exotic mosquito species, not only new cases of some of these diseases may occur, increasing their risk, but also other mosquito-borne diseases may be introduced constituting challenges for the XXI century, demanding a continued surveillance in a Public Health perspective.

  9. Mosquito Records from Mexico: The Mosquitoes (Diptera: Culicidae) of Tamaulipas State.

    Science.gov (United States)

    Ortega-Morales, Aldo I; Zavortink, Thomas J; Huerta-Jiménez, Herón; Sánchez-Rámos, Francisco J; Valdés-Perezgasga, Ma Teresa; Reyes-Villanueva, Filiberto; Siller-Rodríguez, Quetzaly K; Fernandez-Salas, Ildefonso

    2015-03-01

    To document the diversity and distribution of mosquito species inhabiting the Mexican state of Tamaulipas, collection trips were conducted to all physiographic regions (Grand Northamerican Plains, Coastal Plain of North Gulf, and Sierra Madre Oriental) and subregions across the state. Additionally, we re-examined mosquito specimens in two Mexican entomological collections: the Collection of Insects and Mites of Medical Importance and the Collection of Arthropods of Medical Importance. In total, 3,931 specimens were collected. These represent the two Culicidae subfamilies Anophelinae and Culicinae, 10 tribes, 17 genera, 27 subgenera, 80 named species, and 2 undescribed species. Of these, 3 tribes, 6 genera, 7 subgenera, and 20 species are new records for the mosquito fauna of Tamaulipas. Fourteen species recorded in the historical records were not found in collections made for this study. Taxonomic notes, new distribution limits, and comments about the medical importance of some of the species collected are reported. © The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Cyt1A from Bacillus thuringiensis Synergizes Activity of Bacillus sphaericus against Aedes aegypti (Diptera: Culicidae)

    Science.gov (United States)

    Wirth, Margaret C.; Federici, Brian A.; Walton, William E.

    2000-01-01

    Bacillus sphaericus is a mosquitocidal bacterium recently developed as a commercial larvicide that is used worldwide to control pestiferous and vector mosquitoes. Whereas B. sphaericus is highly active against larvae of Culex and Anopheles mosquitoes, it is virtually nontoxic to Aedes aegypti, an important vector species. In the present study, we evaluated the capacity of the cytolytic protein Cyt1A from Bacillus thuringiensis subsp. israelensis to enhance the toxicity of B. sphaericus toward A. aegypti. Various combinations of these two materials were evaluated, and all were highly toxic. A ratio of 10:1 of B. sphaericus to Cyt1A was 3,600-fold more toxic to A. aegypti than B. sphaericus alone. Statistical analysis showed this high activity was due to synergism between the Cyt1A toxin and B. sphaericus. These results suggest that Cyt1A could be useful in expanding the host range of B. sphaericus. PMID:10698776

  11. Effects of Different Pyrethroids on Landing Behavior of Female Aedes aegypti, Anopheles quadrimaculatus, and Culex quinquefasciatus Mosquitoes (Diptera: Culicidae)

    Science.gov (United States)

    2009-03-01

    that act on nerve axon sodium channels in a way similar to DDT (Vijverberg et al. 1982). Permethrin -treated bed nets and uniforms rely on the human...seeking female mosquitoes were lured toward the experimenter into a pint-sized paper food container (Neptune, Newark, NJ) with a screen bottom. They... permethrin -treated nets on the be- haviour of Anopheles gambiae and the selection of pyrethroid resistance. Malaria J. 3: 22. Dethier, V. G., L. B

  12. Redescription of Cx. corniger Theobald and Elevation of Culex (Culex) Lactator Dyar and KNAB from Synonymy Based on Specimens from Central America (Diptera: Culicidae)

    Science.gov (United States)

    1989-10-05

    D. Strickman ~011. no. HONC 176, WRBU Act. 1179, crumpled roofing paper, 3 o 5 $1 aG 2P 2L. La Paz : Marcala, 1260 m, 11 Sep 1986, D. Strickman...Jun 1975, J. Hayes ~011. no. CR 601, tire, 1 ? 1 $ 1 aG. Limon: Westfalia , ~5 m, 4 Dee 1962, C. L. Hogue and W. A. Powder ~011. no. 72, 1 Q; 8 km E...Strickman ~011. no. HONC 94, WRBU Act. 1179,2 ? 1 $1 aG 3P 3L. La Paz : Cerro Sosomico, 1200 m, 27 Jul 1986, D. Strickman ~011. no. HONC VOLUME 9 1

  13. Eficiência e Persistência de Três Produtos Comerciais à Base de Bacillus thuringiensis israelensis e Bacillus sphaericus no controle de Culicidae (Diptera em Lagoas de Tratamento de Efluentes

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    Jose Lopes

    2010-11-01

    Abstract. The hematofagic effect caused by females belonging to some species of Culicidae on humans and animals can be directly related to pathogen transmission, allergic reactions and uneasiness. The emergence of populations resistant to chemical insecticides has fostered the use of alternative methods, mainly biological control. The trials were conducted in three effluent treatment lagoons, on larvae of Culicidae to test the efficiency and persistence of commercial products whose active principles are based on Bacillus thuringiensis israelensis Berliner and Bacillus sphaericus Neide. The products tested were Vectolex (a granulated formulation of B. sphaericus, Sphaericus (a liquid formulation of B. sphaericus and Bt-horus (a liquid formulation of B. thuringiensis. The products were applied biweekly and evaluations were conducted 0, 24, 48, 72, and 120 hours after each application. The lagoons were colonized by Culex nigripalpus Theobald (1.5%, Culex saltanensis Dyar (2.25%, and Culex quinquefasciatus Say (96.25%. Bt-horus reduced larvae by 89.06%, 83.97% and 89.96% at 24, 48 and 72 hours after product application, respectively. The granulated and the liquid formulations containing B. sphaericus reduced larvae by 98.89 % and 98.34% 24 hours after application, and by 99.79% and 99.78% after 48 hours, respectively. The products and the different formulations were effective in controlling larvae of all three Culicidae species in lagoons with high levels of organic matter, but the persistence was recorded in two and three days for products containing respectively B. sphaericus and B. thuringiensis israelensis.

  14. Feeding behavior of Mimomyia (Etorleptiomyia) luzonensis (Ludlow, 1905) (Diptera, Culicidae) in Peninsular Malaysia.

    Science.gov (United States)

    Braima, Kamil A; Muslimin, M; M Ghazali, Amir-Ridhwan; Wan-Nor, F; Wilson, J J; Jeffery, J; Abdul-Aziz, N M

    2017-07-01

    Mosquitoes are vectors of various human diseases in the tropics including yellow fever, dengue, malaria and West Nile virus. Mosquitoes can act as vectors between wildlife and humans, which is particularly important for diseases where wild animals serve as reservoirs of parasites in the absence of human infections. Research has mainly focused on the medical impacts of Anopheles, Aedes, Mansonia and Culex, however, very little attention has been directed towards other mosquito genera, especially those which act as vectors of diseases of wildlife. We have observed adults of Mimomyia (Etorleptiomyia) luzonensis (Ludlow, 1905) feeding on a toad, Ingerophrynus parvus, near an oil palm plantation settlement in Setia Alam, Selangor state, Peninsular Malaysia. Mimomyia is known to feed on reptiles and amphibians, and is a documented vector of several arboviruses, including West Nile virus. The observation of Mimomyia feeding on a common toad near a human settlement highlights a need to understand the relationships between mosquitoes, toads and humans from an ecological perspective. We report on-site observations of the feeding habit of Mimomyia; the first records from Malaysia. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Toxicity of (Burseraceae Leaf Fractions against Immature Stages of (Giles and (Say (Diptera: Culicidae

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    Lame Younoussa

    2016-01-01

    Full Text Available Mosquitoes are vectors of several human pathogens, and great attention has recently been placed on insecticides from plant-derived products, in search for mosquito control agents. This study, thus, investigated the potency of Boswellia dalzielii methanol leaf extract and its four fractions as mosquito ovicide, larvicide, and pupicide against Anopheles gambiae and Culex quinquefasciatus . The plant products were tested at the following concentrations: 125, 250, 500, 1000, and 2000 ppm on eggs and 312.5, 625, 1250, and 2500 ppm on the larvae and pupae of the mosquitoes. For results, hatchability of A. gambiae eggs was reduced to 5% with n -hexane fraction at 2000 ppm. Among the plant products tested, n -hexane fraction was most toxic against A. gambiae (LC 50 = 385.9 ppm and C. quinquefasciatus (LC 50 = 3394.9 ppm. The n -hexane fraction of B. dalzielii might be used as a mosquitocidal agent in the breeding sites of A. gambiae and C. quinquefasciatus .

  16. Population dynamics of adult mosquitoes (Diptera: Culicidae) in malaria endemic villages of Kuala Lipis, Pahang, Malaysia.

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    Ali, Wan Najdah Wan Mohamad; Ahmad, Rohani; Nor, Zurainee Mohamed; Ismail, Zamree; Lim, Lee Han

    2011-03-01

    Mosquitoes in malaria endemic areas needs to be monitored constantly in order to detect demographic changes that could affect control measures. A 12-month mosquito population survey was conducted in several malaria endemic areas in Pos Lenjang, Kuala Lipis, Pahang, Malaysia. Collection of mosquitoes using a human landing catch technique was carried out indoors and outdoors for 12 hours from 7:00 PM to 7:00 AM for 42 nights. Anopheles maculatus Theobald (31.0%), Armigeres flavus Leicester (11.3%), Armigeres annulitarsis Leicester (11.0%), Culex vishnui Theobald (9.6%) and Aedes albopictus Skuse (7.0%) were the predominant species caught in the study area. The salivary gland and midgut of all anopheline mosquitoes were dissected to determine the presence of malaria parasites but none were positive. A high rate of human biting by An. maculatus was detected during December, but the rate was lower in January. Mosquito larvae were carried by the rapid current of the river downstream causing a decrease in the larvae population. Of the five predominant species, only Ar. annulitarsis exhibited a significant positive correlation in numbers with monthly rainfall (p < 0.05). An. maculatus biting activity peaked during 10:00 PM to 11:00 PM. Ae. albopictus, Ar. annulitarsis, and Ar. flavus exhibited similar activities which peaked during 7:00 PM to 8.00 PM.

  17. Time to death from starvation and compulsive killing by the larvae of Toxorhynchites splendens (Diptera: Culicidae).

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    Amalraj, D D; Das, P K

    1994-11-01

    Time to death from starvation and compulsive killing without eating of the prey by larvae of Toxorhynchites splendens were studied in the laboratory. The first and second instars survived without food for 3 days while third and fourth instars survived for 7.8 and 14 days, respectively. When the corresponding instars of Aedes aegypti, Anopheles stephensi or Culex quinquefasciatus were offered, the number of prey killed but not eaten ranged from 0 to 15 per 40 prey larvae. Compulsive killing of Ae. aegypti was mainly at its third instar by 9- and 10-day old T. splendens. Compulsive killing of An. stephensi was mainly at its second and third instars by young and older ages of T. splendens but older T. splendens also killed fourth instar of An. stephensi. Compulsive killing of Cx. quinquefasciatus was of all its instars and mainly by young T. splendens. There was a significant negative correlation between the amount of food eaten per predator and the number of prey killed compulsively. The number of larvae killed and eaten were much larger than number killed compulsively, except in the case of third instar Ae. aegypti and 9-10-day old T. splendens.

  18. Species Composition and Ecological Aspects of Immature Mosquitoes (Diptera: Culicidae in Bromeliads in Urban Parks in the City of São Paulo, Brazil

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    Walter Ceretti-Junior

    2015-10-01

    Full Text Available Background: Bromeliads can be epiphytic, terrestrial or saxicolous and use strategies to allow water to be re­tained in their leaf axils, where various arthropods can be found. These include mosquitoes, whose larvae are the most abundant and commonly found organisms in the leaf axils. The objective of this study was to look for im­mature forms of mosquitoes (the larval and pupal stages in bromeliads in municipal parks in São Paulo and to discuss the ecological and epidemiological importance of these insects.Methods: From October 2010 to July 2013, immature mosquitoes were collected from bromeliads in 65 munici­pal parks in the city of São Paulo, Brazil, using suction samplers. The immature forms were maintained until adult forms emerged, and these were then identified morphologically.Results: Two thousand forty-two immature-stage specimens belonging to the genera Aedes, Culex, Trichoprosopon, Toxorhynchites, Limatus and Wyeomyia were found in bromeliads in 15 of the 65 parks visited. Aedes albopictus was the most abundant species (660 specimens collected, followed by Culex quinquefasciatus (548 specimens and Cx. (Microculex imitator (444. The taxa with the most widespread distribution were Ae. aegypti and Toxorhynchites spp, followed by Ae. albopictus and Cx. quinquefasciatus.Conclusion: Bromeliads in urban parks are refuges for populations of native species of Culicidae and breeding sites for exotic species that are generally of epidemiological interest. Hence, administrators and surveillance and mosquito-control agencies must constantly monitor these microenvironments as the presence of these species endangers the health of park users and employees as well as people living near the parks. 

  19. Species Composition and Ecological Aspects of Immature Mosquitoes (Diptera: Culicidae) in Bromeliads in Urban Parks in the City of São Paulo, Brazil.

    Science.gov (United States)

    Ceretti-Junior, Walter; de Oliveira Christe, Rafael; Rizzo, Marco; Strobel, Regina Claudia; de Matos Junior, Marco Otavio; de Mello, Maria Helena Silva Homem; Fernandes, Aristides; Medeiros-Sousa, Antônio Ralph; de Carvalho, Gabriela Cristina; Marrelli, Mauro Toledo

    2016-03-01

    Bromeliads can be epiphytic, terrestrial or saxicolous and use strategies to allow water to be retained in their leaf axils, where various arthropods can be found. These include mosquitoes, whose larvae are the most abundant and commonly found organisms in the leaf axils. The objective of this study was to look for immature forms of mosquitoes (the larval and pupal stages) in bromeliads in municipal parks in São Paulo and to discuss the ecological and epidemiological importance of these insects. From October 2010 to July 2013, immature mosquitoes were collected from bromeliads in 65 municipal parks in the city of São Paulo, Brazil, using suction samplers. The immature forms were maintained until adult forms emerged, and these were then identified morphologically. Two thousand forty-two immature-stage specimens belonging to the genera Aedes, Culex, Trichoprosopon, Toxorhynchites, Limatus and Wyeomyia were found in bromeliads in 15 of the 65 parks visited. Aedes albopictus was the most abundant species (660 specimens collected), followed by Culex quinquefasciatus (548 specimens) and Cx. (Microculex) imitator (444). The taxa with the most widespread distribution were Ae. aegypti and Toxorhynchites spp, followed by Ae. albopictus and Cx. quinquefasciatus. Bromeliads in urban parks are refuges for populations of native species of Culicidae and breeding sites for exotic species that are generally of epidemiological interest. Hence, administrators and surveillance and mosquito-control agencies must constantly monitor these microenvironments as the presence of these species endangers the health of park users and employees as well as people living near the parks.

  20. Spatial distribution of Culicidae (Diptera larvae, and its implications for Public Health, in five areas of the Atlantic Forest biome, State of São Paulo, Brazil

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    Rafael Piovezan

    Full Text Available ABSTRACT In view of the adaptive ability of mosquitoes and their role in the transport of infective agents, entomological surveys undertaken in transitional environments are very important for the determination of the risk they represent for Public Health. Among the principal vectors of the infectious agents involved in the occurrence of important arboviruses, such as dengue, for example, are the Culicidae-insects capable of installing themselves in the urban nuclei, which exist within areas containing vestigial forests. This present study conducted a survey of mosquito species by means of traps to catch their larvae installed in five rural areas within the Atlantic Forest domain and containing its vestigial vegetation in the municipality of Santa Bárbara D'Oeste, São Paulo, Brazil. A total of 13,241 larvae belonging to six mosquito species were collected on 920 occasions (32.52% of positive collections. Aedes albopictus (64.23% and Aedes aegypti (32.75% were the most frequent, followed by Culex quinquefasciatus (1.32%, Aedes fluviatilis (1.04%, Culex Complex Coronator (0.40% and Toxorhynchites theobaldi (0.22%. Three areas were analyzed by means of Simpson's diversity index and the spatial analysis showed that the sites with the greatest abundance of Ae. aegypti presented lower diversity values and were associated with more highly consolidated urban nuclei. The vector of dengue, chikungunya and zika has great infesting ability in urban areas, which means that the early implementation of entomological surveillance and control activities in specific areas - such as transitional ones - is highly important.

  1. Crouching Tiger, Hidden Trouble: Urban Sources of Aedes albopictus (Diptera: Culicidae) Refractory to Source-Reduction

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    Unlu, Isik; Farajollahi, Ary; Strickman, Daniel; Fonseca, Dina M.

    2013-01-01

    Our ultimate objective is to design cost-effective control strategies for Aedes albopictus, the Asian tiger mosquito, an important urban nuisance and disease vector that expanded worldwide during the last 40 years.  We conducted mosquito larval surveys from May through October 2009 in the City of Trenton, New Jersey, USA, while performing intensive monthly source-reduction campaigns that involved removing, emptying, or treating all accessible containers with larvicides and pupicides. We examined patterns of occurrence of Ae. albopictus and Culex pipiens, another urban mosquito, among different container types by comparing observed and expected number of positive containers of each type. Expected use was based on the relative frequency of each container type in the environment. Aedes albopictus larvae and pupae were found significantly more often than expected in medium volumes of water in buckets and plant saucers but were rarely collected in small volumes of water found in trash items such as discarded cups and cans. They were also absent from large volumes of water such as in abandoned swimming pools and catch basins, although we consistently collected Cx. pipiens from those habitats. The frequency of Ae. albopictus in tires indicated rapid and extensive use of these ubiquitous urban containers. Standard larval-based indices did not correlate with adult catches in BG-Sentinel traps, but when based only on Ae. albopictus key containers (buckets, plant saucers, equipment with pockets of water, and tires) they did. Although we found that only 1.2% of the 20,039 water-holding containers examined contained immature Ae. albopictus (5.3% if only key containers were counted), adult populations were still above nuisance action thresholds six times during the 2009 mosquito season. We conclude that in urban New Jersey, effective source reduction for Ae. albopictus control will require scrupulous and repeated cleaning or treatment of everyday use containers and extensive

  2. Culicidae (Diptera em área sob influência de construção de represa no Estado de São Paulo Culicidae (Diptera in a dam construction area in the state of São Paulo, Brazil

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    Marcia Bicudo de Paula

    2007-04-01

    Full Text Available OBJETIVO: Descrever a fauna Culicidae em área sob impacto da modificação ambiental causada pela construção de represa. MÉTODOS: Foi estudada a área onde estava sendo construída a Represa Porto Primavera no município de Presidente Epitácio, SP. As capturas dos culicídeos foram realizadas mensalmente, em seis pontos exploratórios antes do seu enchimento e em um ponto fixo, um ano antes (1997-1998 e outro depois do primeiro enchimento (1999-2000. Mosquitos adultos foram capturados com aspirador, no período matutino, e com armadilhas de Shannon e CDC, no período crepuscular vespertino. Os imaturos foram coletados por meio de conchadas nos criadouros maiores e com pipeta, nos menores. RESULTADOS: No período anterior ao enchimento da represa foram coletados 944 exemplares de culicídeos imaturos, distribuídos em dez gêneros. O total de adultos foi de 14.932, dos quais 7.031 mosquitos (em dez gêneros foram capturados nos pontos exploratórios e 7.901 espécimes, distribuídos em oito gêneros, no ponto fixo. Após a primeira etapa de enchimento da represa, o total de imaturos foi de 1.201 exemplares, distribuídos em quatro gêneros, e o total de mosquitos capturados foi de 5.912, distribuídos em nove gêneros. Houve redução populacional de espécies dos gêneros Aedes e Psorophora e aumento no número de espécimes dos gêneros Aedeomyia, Anopheles, Culex (Melanoconion, Mansonia e Uranotaenia. CONCLUSÕES: As mudanças ambientais decorrentes da construção da Represa Porto Primavera favoreceram o aumento da densidade de algumas populações de culicídeos vetores e que geram incômodo, com riscos potenciais de transmissão de patógenos para humanos.OBJECTIVE: To describe the culicidae fauna in an area impacted by environmental changes caused by the construction of a dam. METHODS: The studied area was the Porto Primavera dam construction site in Southeastern Brazil. Monthly culicidae samples were taken in six exploratory sites in

  3. Evaluation of leaf aqueous extract and synthesized silver nanoparticles using Nerium oleander against Anopheles stephensi (Diptera: Culicidae).

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    Roni, Mathath; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Hwang, Jiang-Shiou

    2013-03-01

    Green nanoparticle synthesis has been achieved using environmentally acceptable plant extract and ecofriendly reducing and capping agents. The present study was carried out to establish the larvicidal activity of synthesized silver nanoparticles (AgNPs) using leaf extract of Nerium oleander (Apocynaceae) against the first to fourth instar larvae and pupae of malaria vector, Anopheles stephensi (Diptera: Culicidae). Nanoparticles are being used in many commercial applications. It was found that aqueous silver ions can be reduced by the aqueous extract of the plant parts to generate extremely stable silver nanoparticles in water. The results were recorded from UV-Vis spectrum, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy analysis. The production of the AgNPs synthesized using leaf extract of N. oleander was evaluated through a UV-Vis spectrophotometer in a wavelength range of 200 to 700 nm. This revealed a peak at 440 nm in N. oleander leaf extracts, indicating the production of AgNPs. The FTIR spectra of AgNPs exhibited prominent peaks at 509.12 cm(-1) (C-H bend alkenes), 1,077.05 cm(-1) (C-O stretch alcohols), 1,600.63 cm(-1) (N-H bend amines), 2,736.49 and 2,479.04 cm(-1) (O-H stretch carboxylic acids), and 3,415.31 cm(-1) (N-H stretching due to amines group). An SEM micrograph showed 20-35-nm-size aggregates of spherical- and cubic-shaped nanoparticles. EDX showed the complete chemical composition of the synthesized nanoparticles of silver. Larvicidal activity of aqueous leaf extract of N. oleander and synthesized AgNPs was carried out against Anopheles stephensi, and the results showed that the highest larval mortality was found in the synthesized AgNPs against the first to fourth instar larvae and pupae of Anopheles stephensi with the following values: LC(50) of instar larvae 20.60, 24.90, 28.22, and 33.99 ppm; LC(90) of instar larvae 41.62, 50.33, 57.78, and 68.41

  4. [Morphology and cytochemistry of Aedes aegypti's cell cultures (Diptera: Culicidae) and susceptibility to Leishmania panamensis (Kinetoplastida: Trypanosomatidae)].

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    Miranda, Alfonso Arturo; Sarmiento, Ladys; Caldas, María Leonor; Zapata, Cristina; Bello, Felio Jesús

    2008-06-01

    Morphology and cytochemistry of Aedes aegypti's cell cultures (Diptera: Culicidae) and susceptibility to Leishmania panamensis (Kinetoplastida: Trypanosomatidae). The first cellular line of Aedes aegypti was developed by Grace in 1966; afterwards, other cellular lines of this species have been generated. These have been used for the study of pathogenic organisms like viruses, bacteria and parasites, which demonstrates their importance in biomedical applications. This research describes, for the first time, some cytochemical characteristics of A. aegypti cell cultures, that were infected with (MHOM/CO/87CL412) strain of Leishmania panamensis. A morphological study of the cell culture was also carried out. Maintenance of the cell culture, parasites and infection in vitro were carried out in the Laboratory of Entomology, Cell Biology and Genetics of the Universidad de La Salle. The cell cultures infected with the parasite were maintained in a mixture of mediums Grace/L15, supplemented with 10 % fetal bovine serum (FBS) at pH 6.8 and a temperature of 26 degrees C, during 3, 6 and 9 post-infection days. After this, these cell cultures were processed through High Resolution Light Microscopy (HRLM) and Transmission Electron Microscopy (TEM) based on standard protocols defined by the Group of Microscopy and Image Analyses of the Instituto Nacional de Salud. Semi-fine slices of 1 microm colored with toluidine blue were used for the morphological analysis of the culture, and ultra fine cuts of 60 to 90 nm stained with uranyl acetate and lead citrate where used for the ultrastructural study. In addition, PAS and peroxidase staining was carried out in cells fixed with methanol. The morphometric study was analyzed with software ImageJ (NIH). In the semi-fine slices, small cells were observed showing fibroblastic appearance 10.84 +/- 2.54 microm in length and 5.31 +/- 1.26 microm wide; other cells had epithelial appearance with a great peripheral nucleus, voluminous and

  5. Occurence of larval Culicidae (Diptera in water retained in Aquascypha hydrophora (Fungus: Stereaceae in Central Amazônia, Brazil

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    Ferreira Ruth LM

    2001-01-01

    Full Text Available The community structure of insects, especially mosquito larvae, in water held in the fungus Aquascypha hydrophora (Berk. Reid (Stereaceae is reported. The study was done in the Adolpho Ducke Forest Reserve, 26 km east of Manaus, AM, Brazil, from September 1998 through November 1999. The most abundant entomofauna were immature Culicidae (n = 121 91.7%, followed by adult Dytiscidae (n = 3 2.3%, immature Chironomidae (n = 5 3.8% and immature Tipulidae (n = 3 2.3%. Culicidae associated with A. hydrophora comprised species of the subfamilies Anophelinae and Culicinae.

  6. [Aedes albopictus (Diptera: Culicidae) in Rome: experimental study of relevant control strategy parameters].

    Science.gov (United States)

    Pombi, M; Costantini, C; della Torre, A

    2003-06-01

    Since 1997, Aedes albopictus has colonised and then rapidly invaded the city of Rome (Italy) and its peripheral areas. Presently, the control of this mosquito in Italy relies mainly on larvicidal treatment of street storm sewer catch basins with the organophosphate temephos. We have therefore obtained baseline data on the susceptibility to temephos of the Roman Ae. albopictus population by laboratory bioassays on F1 fourth-instar larvae following standard WHO protocols. Estimated lethal concentrations were 0.014 mg/l (LC50) and 0.022 mg/l (LC90) indicating a lack of resistance to this compound. The persistence of temephos in sewer catch basins was evaluated by follow-up of catch basins treated with a dose of 1.5 mg of active ingredient. Mosquito larvae were recovered in 10% and 50% of the treated basins at 9 and 18 days posttreatment, respectively. In order to understand the relative contribution of this larval habitat to adult populations, we conducted a survey in the Zoo of Rome to estimate the larval density of mosquitoes breeding in sewer catch basins. A complete census of a 16.5 ha area mapped 243 catch basins, but only 25 (10.3%) contained water; of the latter 8 (32.0%) hosted mosquito larvae. All positive catch basins contained larvae of Culex pipiens, which were associated with Culiseta longiareolata and/or Ae. albopictus in 6 and 3 cases, respectively. A longitudinal survey of one catch basin over 4 months showed that the mean larval density of Ae. albopictus was markedly lower than that of Cx pipiens and Cs. Iongiareolata, ranging between 0 and 1.3 larvae/dip as compared to 0-33.2 and 0-22.7 larvae/dip, respectively. However, adult densities of Ae. albopictus in this area estimated during the same period with 20 ovitraps showed consistently high values (proportion of positive ovitraps around 100%). These preliminary observations suggest that whenever alternative larval biotopes other than sewer catch basins are widely available, they might be more

  7. [Presence of Haemagogus equinus Theobald, 1903 (Diptera: Culicidae), in Soledad and Malambo, in the Province of Atlántico, Colombia].

    Science.gov (United States)

    Maestre-Serrano, Ronald; Vergara-Sanchez, Consuelo; Berrueco-Rodriguez, Guillermo; Bello-Novoa, Betsy; Brochero, Helena

    2008-03-01

    Yellow fever is a serious illness public health importance and is transmitted by mosquitoes of the genera Haemagogus and Sabethes in the rural and forest environments, and by Aedes aegypti in the urban setting. In Colombia, Haemagogus janthinomys and H. equinus are considered efficient vectors of this viral disease. The presence of the mosquito Haemagogus equinus was recorded over an 8 year period, in the periurban areas of the Soledad and Malambo municipalities (Atlantico Province) of northern Colombia. The data was obtained from records of the entomological collections from two collection sites: (1) 14 larva traps located at the Erneasto Cortissoz airport in the municipality of Soledad between 1997--2005 and (2) 10 larva traps located at Vergara and Velasco Batallion in the municipality of Malambo in 2005. Haemogogus equinus was reported for the first time in Soledad in 1998. In the following 8 years, 197 larvae were reported. The individuals were found sharing the trap with Aedes aegypti, Culex nigripalpus and Uranotaenia lowii. In Malambo, the first discovery of H.equinus occurred in 2005, with a total of 641 larvae. No other Culicidae were associated with it. The presence of H. equinus in larvitraps located near the urban zone, shows adaptation to the use of artificial containers as larval habitats, Urbanization of this species in zones with a high Ae. aegypti infestation index increases the potential introduction of sylvan yellow fever virus and constitutes a risk for re-emergence of urban cycles of yellow fever.

  8. Molecular approaches for blood meal analysis and species identification of mosquitoes (Insecta: Diptera: Culicidae) in rural locations in southern England, United Kingdom.

    Science.gov (United States)

    Hernández-Triana, Luis Miguel; Brugman, Victor Albert; Prosser, Sean Williams John; Weland, Chris; Nikolova, Nadya; Thorne, Leigh; Marco, Mar Fernández DE; Fooks, Anthony Richard; Johnson, Nicholas

    2017-04-03

    Thirty-four species of Culicidae are present in the UK, of which 15 have been implicated as potential vectors of arthropod-borne viruses such as West Nile virus. Identification of mosquito feeding preferences is paramount to the understanding of vector-host-pathogen interactions which, in turn, would assist in the control of disease outbreaks. Results are presented on the application of DNA barcoding for vertebrate species identification in blood-fed female mosquitoes in rural locations. Blood-fed females (n = 134) were collected in southern England from rural sites and identified based on morphological criteria. Blood meals from 59 specimens (44%) were identified as feeding on eight hosts: European rabbit, cow, human, barn swallow, dog, great tit, magpie and blackbird. Analysis of the cytochrome c oxidase subunit I mtDNA barcoding region and the internal transcribed spacer 2 rDNA region of the specimens morphologically identified as Anopheles maculipennis s.l. revealed the presence of An. atroparvus and An. messeae. A similar analysis of specimens morphologically identified as Culex pipiens/Cx. torrentium showed all specimens to be Cx. pipiens (typical form). This study demonstrates the importance of using molecular techniques to support species-level identification in blood-fed mosquitoes to maximize the information obtained in studies investigating host feeding patterns.

  9. Mosquitos antropofílicos de atividade matutina em Mata Atlântica, Florianópolis, SC Mosquitoes with morning biting activity in the Atlantic forest, Brazil (Diptera, Culicidae

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    Uéslei Paterno

    2004-02-01

    Full Text Available Como os trabalhos sobre Culicidae em Santa Catarina foram restritos a anofelíneos e a Culex quinquefasciatus, pela ocorrência, no passado, de malária e de filariose, a fauna de mosquitos em áreas de mata é pouco conhecida. Assim, foi realizado um levantamento dos culicídeos que atacam o homem pela manhã em trilha situada numa unidade de conservação da Mata Atlântica na Ilha de Santa Catarina, freqüentada por estudantes e turistas. Foram coletados 358 exemplares de 22 espécies, das quais 14 são relatadas pela primeira vez no Estado. Runchomyia reversa e Ochlerotatus scapularis foram as espécies predominantes, com grande diversidade de espécies de Wyeomyia (Phoniomyia.Previous studies on Culicidae in the state of Santa Catarina, Brazil, were limited to Anophelinae and Culex quinquefasciatus due to the past occurrence of malaria and filariasis but the mosquito fauna in forested areas is still almost unknown. It was carried out a survey of mosquitoes with morning biting activity in a tourist trekking trail of an Atlantic forest reserve area in the island of Santa Catarina. There were collected 358 specimens of 22 species, 14 of them reported for the first time in the state. Runchomyia reversa and Ochlerotatus scapularis were the predominant species. There was a great diversity of Wyeomyia (Phoniomyia species.

  10. Crepuscular activity of culicids (Diptera, Culicidae in the peridomicile and in the remaining riparian forest in Tibagi river, State of Paraná, Brazil

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    Gerson A. Müller

    2012-03-01

    Full Text Available Crepuscular activity of culicids (Diptera, Culicidae in the peridomicile and in the remaining riparian forest in Tibagi river, State of Paraná, Brazil. Human-attracted mosquitoes were collected for one hour, around sunset time (half hour before and half after, from April to December 2006, in two environments (riparian forest and near houses, in Tibagi river basin, Palmeira municipality, State of Paraná. Seven-hundred forty-nine mosquitoes, belonging to 13 species, were collected. Psorophora champerico Dyar & Knab, 1906 (42.86% and Psorophora discrucians (Walker, 1856 (40.59% were the most frequent species. No significant differences between quantities of Ps. champerico (t = -0.792; d.f. = 16; p = 0.43 and Ps. discrucians (t = 0.689; d.f. = 16; p = 0.49 obtained in riparian forest and near houses were observed, indicating similar conditions for crepuscular activity of these species in both environments. Psorophora champerico and Ps. discrucians responded (haematophagic activity to environmental stimuli associated with the twilight hours differently in distinct habitats studied. The former species is registered for the first time in the Atlantic forest biome.

  11. Larvicidal activity of essential oils of Citrus sinensis and Citrus aurantium (Rutaceae cultivated in Morocco against the malaria vector Anopheles labranchiae (Diptera: Culicidae

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    Fouad El-Akhal

    2015-06-01

    Full Text Available Objective: To study the larvicidal activity of essential oils of two aromatic and medicinal plants, Citrus aurantium (C. aurantium and Citrus sinensis (C. sinensis (Rutaceae cultivated in North Eastern Morocco, against the larvae of the malaria vector Anopheles labranchiae (An. labranchiae (Diptera: Culicidae. Methods: Biological tests were realized according to a methodology inspired from standard World Health Organization protocol. The mortality counts were made after 24 h and LC50 and LC 90 values were calculated. Results: Bioassays revealed that these oils had remarkable larvicidal properties. The minimum levels necessary to achieve 100% mortality of An. labranchiae larvae were evaluated at 160 mg/L for C. aurantium and 640 mg/L for C. sinensis. Essential oil of C. aurantium remained the most efficient (LC50 = 22.64 mg/L, LC90 = 83.77 mg/L, while those of C. sinensis was the least (LC50 = 77.55 mg/L, LC90 = 351.36 mg/L. Conclusions: These results suggest that the essential oils isolated from Citrus plants have the potential to be used as an ideal ecofriendly approach for the control An. labranchiae.

  12. Chlorfenapyr: irritant effect compared to other insecticides and its intrinsic toxicity in multiple-insecticide-susceptible and -resistant Anopheles stephensi (Diptera: Culicidae).

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    Verma, Vaishali; Elamathi, N; Velamuri, Poonam S; Sreehari, U; Agrawal, O P; Raghavendra, K

    2015-03-01

    For effective management of vector resistance there is a need for new insecticide molecules with novel modes of action. For desired toxic effect of an insecticide, apart from other behavioural aspects, toxicity and chemical nature of the molecule are important that may cause irritability in the mosquito to the insecticide affecting the uptake. In this study, a pyrrole class insecticide, chlorfenapyr (a late acting insecticide) was tested for its irritability against multiple-insecticide-susceptible and -resistant strains of Anopheles stephensi Liston 1901 (Diptera: Culicidae). Studies were conducted to assess the irritability due to chlorfenapyr, DDT, malathion, deltamethrin and permethrin and intrinsic toxicity of chlorfenapyr in multiple-insecticide-susceptible and -resistant laboratory strains of An. stephensi following standard WHO methods. Chlorfenapyr molecule has shown least irritant effect against susceptible and resistant strains among all the insecticides tested allowing more landing time to the vector species on the impregnated surfaces to pick-up lethal dose. Chlorfenapyr could be an ideal insecticide for management of multiple-insecticide-resistance including pyrethroids.

  13. A low-cost mesocosm for the study of behaviour and reproductive potential in Afrotropical mosquito (Diptera: Culicidae) vectors of malaria.

    Science.gov (United States)

    Jackson, B T; Stone, C M; Ebrahimi, B; Briët, O J T; Foster, W A

    2015-03-01

    A large-scale mesocosm was constructed and tested for its effectiveness for use in experiments on behaviour, reproduction and adult survivorship in the Afrotropical malaria vector Anopheles gambiae s.s. Giles (Diptera: Culicidae) in temperate climates. The large space (82.69 m(3) ) allowed for semi-natural experiments that increased demand on a mosquito's energetic reserves in an environment of widely distributed resources. A one-piece prefabricated enclosure, made with white netting and vinyl, prevented the ingress of predators and the egress of mosquitoes. Daylight and white materials prompted the mosquitoes to seclude themselves in restricted daytime resting sites and allowed the easy collection of dead bodies so that daily mortality could be assessed accurately using a method that accounts for the loss of a proportion of bodies. Here, daily, age-dependent mortality rates of males and females were estimated using Bayesian Markov chain Monte Carlo simulation. In overnight experiments, mosquitoes successfully located plants and took sugar meals. A 3-week survival trial with a single cohort demonstrated successful mating, blood feeding, oviposition and long life. The relatively low cost of the mesocosm and the performance of the mosquitoes in it make it a viable option for any behavioural or ecological study of tropical mosquitoes in which space and seasonal cold are constraining factors. © 2014 The Royal Entomological Society.

  14. Chemical Compositions of the Peel Essential Oil of Citrus aurantium and its Natural Larvicidal Activity against the Malaria Vector Anopheles stephensi (Diptera: Culicidae in Comparison with Citrus paradisi

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    Alireza Sanei-Dehkordi

    2016-10-01

    Full Text Available Background: Recently, essential oils and extracts derived from plants have received much interest as potential bioactive agents against mosquito vectors.Methods: The essential oils extract from fresh peel of ripe fruit of Citrus aurantium and Citrus paradisi were tested against mosquito vector Anopheles stephensi (Diptera: Culicidae under laboratory condition. Then chemical com­position of the essential oil of C. aurantium was analyzed using gas chromatography-mass spectrometry (GC–MS.Results: The essential oils obtained from C. aurantium, and C. paradisi showed good larviciding effect against An. stephensi with LC50 values 31.20 ppm and 35.71 ppm respectively. Clear dose response relationships were established with the highest dose of 80 ppm plant extract evoking almost 100% mortality. Twenty-one (98.62% constituents in the leaf oil were identified. The main constituent of the leaf oil was Dl-limonene (94.81.Conclusion: The results obtained from this study suggest that the limonene of peel essential oil of C. aurantium is promising as larvicide against An. stephensi larvae and could be useful in the search for new natural larvicidal compounds.

  15. In vitro evaluation of the effect of botanical formulations used in the control of Aedes aegypti L. (Diptera: Culicidae on liver enzymes.

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    Karla Rejane de Andrade Porto

    Full Text Available Abstract: INTRODUCTION: Dengue fever is a viral disease transmitted by the Aedes aegypti Linn. (1792 (Diptera: Culicidae mosquito, which is endemic in several regions of Brazil. Alternative methods for the control of the vector include botanical insecticides, which offer advantages such as lower environmental contamination levels and less likelihood of resistant populations. Thus, in this study, the ability of botanical insecticide formulations to inhibit the activity of the liver enzymes serum cholinesterase and malate dehydrogenase was evaluated. METHODS: Inhibition profiles were assessed using in vitro assays for cholinesterase and malate dehydrogenase activity and quantitated by ultraviolet-visible spectroscopy at 410nm to 340nm. RESULTS Insecticide products formulated from cashew nutshell liquid [A] and ricinoleic acid [B] showed cholinesterase activity levels of 6.26IU/mL and 6.61IU/mL, respectively, while the control level for cholinesterase was 5-12IU/mL. The products did not affect the level of 0.44IU/mL established for malate dehydrogenase, as the levels produced by [A] and [B] were 0.43IU/mL and 0.45IU/mL, respectively. CONCLUSIONS Our findings show that in vitro testing of the formulated products at concentrations lethal to A. aegypti did not affect the activity of cholinesterase and malate dehydrogenase, indicating the safety of these products.

  16. The Climate Range Expansion of Aedes albopictus (Diptera: Culicidae) in Asia Inferred From the Distribution of Albopictus Subgroup Species of Aedes (Stegomyia).

    Science.gov (United States)

    Mogi, M; Armbruster, P A; Tuno, N; Aranda, C; Yong, H S

    2017-11-07

    We compared climatic distribution ranges between Aedes albopictus (Skuse) (Diptera: Culicidae) and the five wild (nondomesticated) species of Albopictus Subgroup of Scutellaris Group of Aedes (Stegomyia) in southern Asia. Distribution sites of the wild species concentrate in seasonal forest and savannah climate zones in India, Indochina, and southern China. The distribution of Ae. albopictus is broader than the wild species under 1) tropical rain-forest climate, 2) steppe and temperate savannah climate, and 3) continental climate with large seasonal temperature variation (hot summer and cold winter) at temperate lowlands (northernmost sites 40°N in Ae. albopictus vs 32°N in the wild species). However, the distribution of Ae. albopictus is more limited at tropical and subtropical highlands where the climate is cool but less continental (small seasonal variation, mild summer, and winter). We discuss a possibility that the broader climate ranges of Ae. albopictus are ecological or eco-evolutionary consequences of adaptation to human habitats. We also propose a general scenario for the origin, dispersal, and adaptation of Ae. albopictus in Asia as a hypothesis for future research. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Evaluation of Lambda-Cyhalothrin and Pyriproxyfen Barrier Treatments for Aedes albopictus (Diptera: Culicidae) Management in Urbanized Areas of New Jersey.

    Science.gov (United States)

    Unlu, Isik; Williams, Gregory M; Rochlin, Ilia; Suman, Devi; Wang, Yi; Chandel, Kshitij; Gaugler, Randy

    2017-12-13

    Mosquito control programs in the United States are still searching for best management practices to control the Asian tiger mosquito, Aedes albopictus (Skuse; Diptera: Culicidae). Most intervention methods for this species are either labor intensive (e.g., source reduction) or short-term (e.g., ultra-low-volume adulticiding). We investigated the effectiveness of barrier spray pesticide applications within urban and suburban residential yards in New Jersey as a control strategy using a before-after-control-impact (BACI) approach. Applications of Demand CSR pyrethroid (9.7% AI lambda-cyhalothrin) only or combined Demand CSR and Archer IGR insect growth regulator (1.3% AI pyriproxyfen) applications resulted in significant and similar decreases in adult mosquito abundance post-treatment ranging from 78 to 74% respectively, compared with the untreated control. Both insecticides exceeded the 70% reduction threshold considered as effective for Ae. albopictus control for 2 to 4 wk. However, applications of Archer IGR alone did not reduce adult mosquito abundance. The field study results were supported by laboratory no-choice bioassays using treated leaf foliage. Our study is the first data driven evidence of the residual efficacy of barrier pesticide applications in New Jersey with lambda-cyhalothrin that provided significant reductions in adult Ae. albopictus populations for an extended duration. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  18. Ecological aspects of Microsporidia parasitizing in natural populations of the Aedes (Diptera: Culicidae) blood-suking mosquitoes in Western Siberia

    OpenAIRE

    SIMAKOVA ANASTASIA V.; PANKOVA TAMARA F.; ISSI IRMA V.; ANDREEVA YULIA V.

    2016-01-01

    We examined microsporidia (1976-2014) in natural populations of blood-sucking Aedes mosquitoes of Western Siberia with the focus on their biodiversity and ecology. In total, we recorded 3' species of Culicidae family mosquitoes in Western Siberia; 22 species of them belong to the univoltine genus Aedes, producing one generation per year (spring). As it has been shown, microsporidians infect '3 mosquito species. In this study, we isolated 26 microsporidian species representing five genera (Amb...

  19. Species composition and habitat characterization of mosquito (Diptera: Culicidae) larvae in semi-urban areas of Dhaka, Bangladesh

    Science.gov (United States)

    Bashar, Kabirul; Rahman, Md. Sayfur; Nodi, Ila Jahan; Howlader, Abdul Jabber

    2016-01-01

    Mosquito larvae are purely aquatic and develop in water bodies, the type of which is more or less specific to each species. Therefore, a study was carried out to identify the habitat characters of different mosquito species along with their species composition in semi-urban area of Dhaka in Bangladesh during the month of May and June 2012. A total of 6088 mosquito larvae belonging to 12 species (Aedes aegypti, Aedes albopictus, Anopheles barbirostris, Anopheles peditaeniatus, Anopheles vagus, Culex gelidus, Culex hutchinsoni, Culex quinquefasciatus, Culex tritaeniorhynchus, Mansonia annulifera, Mansonia uniformis, and Toxorhynchites splendens) under 5 genera were collected from 14 different types of habitats. Culex quinquefsciatus was the dominant (21.7/500 ml) species followed by Cx. tritaeniorhynchus (10.53/500 ml). Dissolved oxygen and chlorophyll a were the preeminent predictors for the abundance of all collected mosquito larvae except Ae. aegypti. Water temperature was positively associated with the breeding of An. vagus (r = 0.421, p = <0.001), An. barbirostris (r = 0.489, p = <0.001) and An. peditaeniatus (r = 0.375, p = <0.001). Water depth, distance from nearest house, emergent plant coverage, and alkalinity were found as the basis of larval abundance. Every Culex species and Tx. splendens (r = 0.359, p = 0.001) were found positively associated with chemical oxygen demand, while Mn. annulifera showed negative association (r = −0.115, p = 0.0297). This study also highlighted that various physicochemical factors affect the presence or abundance of mosquito larvae. PMID:27241953

  20. Estirpes de Bacillus thuringiensis efetivas contra insetos das ordens Lepidoptera, Coleoptera e Diptera Bacillus thuringiensis strains effective against insects of Lepidoptera, Coleoptera and Diptera orders

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    Lílian Botelho Praça

    2004-01-01

    Full Text Available O objetivo deste trabalho foi selecionar entre 300 estirpes de Bacillus thuringiensis as efetivas simultaneamente contra larvas de Spodoptera frugiperda J.E. Smith e Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae, Anthonomus grandis Boheman (Coleoptera: Curculionidae, Aedes aegypti Linnaeus e Culex quinquefasciatus Say (Diptera: Culicidae. Foram selecionadas duas estirpes de B. thuringiensis, denominadas S234 e S997, que apresentaram atividade contra as três ordens de insetos. As estirpes foram caracterizadas por métodos morfológicos, bioquímicos e moleculares. As mesmas apresentaram duas proteínas principais de 130 e 65 kDa, produtos de reação em cadeia da polimerase de tamanho esperado para a detecção dos genes cry1Aa, cry1Ab, cry1Ac, cry1B e cry2 e cristais bipiramidais, cubóides e esféricos.The aim of this work was to select among 300 strains of Bacillus thuringiensis those which are simultaneously effective against larvae of Spodoptera frugiperda J.E. Smith and Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae, Anthonomus grandis Boheman (Coleoptera: Curculionidae, Aedes aegypti Linnaeus and Culex quinquefasciatus Say (Diptera: Culicidae. Two strains of B. thuringiensis were selected, S234 and S997, which presented activity against those three insect orders. Both strains were characterized by morphological, biochemical and molecular methods. They have presented two main proteins with 130 and 65 kDa, polimerase chain reaction products with expected sizes for detection of the genes cry1Aa, cry1Ab, cry1Ac, cry1B and cry2 and bipiramidal, cubical and spherical crystals.

  1. Crepuscular activity of culicids (Diptera, Culicidae in the peridomicile and in the remaining riparian forest in Tibagi river, State of Paraná, Brazil

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    Gerson A. Müller

    2012-03-01

    Full Text Available Crepuscular activity of culicids (Diptera, Culicidae in the peridomicile and in the remaining riparian forest in Tibagi river, State of Paraná, Brazil. Human-attracted mosquitoes were collected for one hour, around sunset time (half hour before and half after, from April to December 2006, in two environments (riparian forest and near houses, in Tibagi river basin, Palmeira municipality, State of Paraná. Seven-hundred forty-nine mosquitoes, belonging to 13 species, were collected. Psorophora champerico Dyar & Knab, 1906 (42.86% and Psorophora discrucians (Walker, 1856 (40.59% were the most frequent species. No significant differences between quantities of Ps. champerico (t = -0.792; d.f. = 16; p = 0.43 and Ps. discrucians (t = 0.689; d.f. = 16; p = 0.49 obtained in riparian forest and near houses were observed, indicating similar conditions for crepuscular activity of these species in both environments. Psorophora champerico and Ps. discrucians responded (haematophagic activity to environmental stimuli associated with the twilight hours differently in distinct habitats studied. The former species is registered for the first time in the Atlantic forest biome.Atividade crepuscular de culicídeos (Diptera, Culicidae no peridomicílio e remanescentes de matas ciliares do Rio Tibagi. Estado do Paraná, Brasil. Mosquitos atraídos por humanos foram coletados por uma hora em torno do crepúsculo vespertino (meia hora antes e meia hora depois, de abril a dezembro de 2006, em dois locais (mata ciliar e peridomicílio na bacia do Rio Tibagi, município de Palmeira, Estado do Paraná. Foram capturados 749 mosquitos distribuídos em 13 espécies. Psorophora champerico Dyar & Knab, 1906 (42,86% e Ps. discrucians (Walker, 1856 (40,59% foram as espécies mais freqüentes. Não foram registradas diferenças significativas entre as médias de indivíduos capturados entre os pontos de mata ciliar e peridomicílio para Ps. champerico (t = -0,792; g.l. = 16; p = 0

  2. Laboratory evaluation of the aqueous extract of Azadirachta indica (neem) wood chippings on Anopheles gambiae s.s. (Diptera: Culicidae) mosquitoes.

    Science.gov (United States)

    Howard, Annabel F V; Adongo, Elizabeth A; Hassanali, Ahmed; Omlin, Francois X; Wanjoya, Anthony; Zhou, Guofa; Vulule, John

    2009-01-01

    Azadirachta indica A. Juss (the neem tree), a source of limonoid insect growth regulatory (IGRs), grows well in many places in sub-Saharan Africa. We explored the potential of neem wood and bark chippings in malaria vector control by evaluating their aqueous extracts as a larvicide and growth disruptor of Anopheles gambiae s.s. (Diptera: Culicidae) under laboratory conditions. Immature stages of the mosquito were tested using WHO guidelines. Fifty percent inhibition of adult emergence (IE50) of all larval instars was obtained with neem chippings in 1 liter of distilled water. For pupae, significant mortality occurred at 5 g/liter. Inhibition of pupation was seen with some larvae staying as LIVs for 9 d before dying. In addition to growth retardation, reduced reaction by larvae to visual and mechanical stimuli observed at higher neem concentrations may make them more susceptible to natural predators. There were no significant differences in the sex ratio of emerged adults or wing length of females compared with the controls. High-performance liquid chromatography of aqueous extracts showed a series of constituents of varying polarity, including the limonoids nimbin and salannin, which were quantified. Azadirachtin was not detected and the observed activities are attributed to other constituents of the chippings. Such larvicides can be particularly effective where larval habitats are relatively large and readily identifiable. Aqueous extracts of neem wood chippings can be produced locally and their use has the potential to be a low-tech component of integrated malaria vector control schemes in sub-Saharan Africa.

  3. Encontro de Haemagogus (Conopostegus leucocelaenus (Diptera: Culicidae, no Município de Porto Alegre, Estado do Rio Grande do Sul Finding of Haemagogus (Conopostegus leucocelaenus (Diptera: Culicidae, in the municipality of Porto Alegre, State of Rio Grande do Sul

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    Almério de Castro Gomes

    2007-08-01

    Full Text Available Em novembro de 2006, foi realizada uma investigação entomológica numa mata nativa do município de Porto Alegre, Estado do Rio Grande do Sul. O resultado foi a captura de várias espécies Culicidae, incluindo o primeiro registro da presença de Haemagogus leucocelaenus na localidade. Esta espécie é considerada vetora do vírus da febre amarela em alguns municípios do Estado, motivando esta comunicação para alertar sobre o potencial da área para circulação do agente etiológico desta doença.In November 2006, an entomological investigation was carried out in a native forest in the municipality of Porto Alegre, State of Rio Grande do Sul. The result was the capture of several Culicidae species, including the first recording of the presence of Haemagogus leucocelaenus in this locality. This species is considered to be a vector for the yellow fever virus in some municipalities of this State, and this was the motivation for the present communication, in order to warn regarding the potential of this area for circulation of the etiological agent for this disease.

  4. Ecologia de mosquitos (Diptera: Culicidae em criadouros naturais e artificiais de área rural do Norte do Estado do Paraná, Brasil: l - Coletas ao longo do leito de ribeirão

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    José Lopes

    1995-06-01

    Full Text Available Objetivando-se conhecer as espécies de Culicidae aptas a colonizarem ambiente de um ribeirão com mata ciliar reduzida e localizado na região Sul do Brasil, foram realizadas capturas com auxílio de rede para coleta de insetos aquáticos. Foram apanhadas as seguintes espécies: Aedes crinifer, Aedomya squamipennis, Anopheles fluminensis, An. intermedius, An. albitarsis, An. argyritarsis, An. evansae, An. galvaoi, An. oswaldoi, An. strodei, An. triannulatus, Chagasia fajardi, Culex bidens, Cx. grupo coronator, Cx. eduardoi, Cx. mollis, Cx. quinquefasciatus, Cx. coppenamensis, Cx. vaxus, Cx. grupo inhibitator, Cx. intrincatus, Cx. (Melanoconion sp., Psorophora saeva (? e Uranotaenia pulcherrima. Para as espécies em que foi capturada uma amostra tida como representativa, foram estudadas a distribuição ao longo da área pesquisada, a flutuação populacional e a correlação com fatores físicos do ambiente. Conclui-se da análise que massas de água orladas por mata ciliar reduzida podem funcionar como refúgio para alguns Culicidae e esta condição pode contribuir decisivamente para o processo de domiciliação de espécies deste grupo.

  5. Efficacy of two pyrethroid insecticides applied as barrier treatments for managing mosquito (Diptera: Culicidae) populations in suburban residential properties.

    Science.gov (United States)

    Trout, R T; Brown, G C; Potter, M F; Hubbard, J L

    2007-05-01

    Increased threat of mosquito-borne disease coupled with decreased tolerance of nuisance mosquitoes has opened a market for pest management professionals to offer mosquito control services for homeowners. A pest management professional applied bifenthrin (0.08%) and lambda-cyhalothrin (0.1%) at their maximum label concentrations as barrier treatments. We tested treatments residual efficacy in reducing adult mosquito populations and compared these chemicals against a water control at 24 residential properties (eight replications by three treatments). Mosquito populations were measured on each property by using five methods: CO2-baited Centers for Disease Control (CDC) light traps (without a light), human landing rates, CDC gravid traps, ovitraps, and sweep nets. Populations were monitored weekly for 2 wk before treatment and 8 wk posttreatment. Additionally, to confirm residual efficacy of each insecticide, a randomly treated leaf underwent a no-choice bioassay with laboratory-reared Aedes albopictus (Skuse). Trap collections were dominantly Aedes albopictus and Culex pipiens L. Both insecticidal treatments significantly reduced Aedes spp. lambda-Cyhalothrin- and bifenthrin-treated sites had 89.5 and 85.1% fewer Ae. albopictus bites than the untreated control, respectively. Ae. albopictus bioassay results showed significant residual efficacy for both insecticides up to 6 wk posttreatment. There were no significant differences between properties treated with the two insecticides. In contrast, Culex spp. were not reduced by either insecticidal treatment. Our study indicated that barrier sprays applied to low-lying vegetation do not properly target adult daytime resting sites for Culex mosquitoes but that they can reduce Aedes mosquitoes. Perhaps by treating upper tree canopies Culex spp. abundance may be reduced.

  6. Changes in species richness and spatial distribution of mosquitoes (Diptera: Culicidae) inferred from museum specimen records and a recent inventory: a case study from Belgium suggests recent expanded distribution of arbovirus and malaria vectors.

    Science.gov (United States)

    Dekoninck, W; Hendrickx, F; Versteirt, V; Coosemans, M; De Clercq, E M; Hendrickx, G; Hance, T; Grootaert, P

    2013-03-01

    Mosquito (Diptera: Culicidae) distribution data from a recent inventory of native and invading mosquito species in Belgium were compared with historical data from the period 1900-1960 that were retrieved from a revision of the Belgian Culicidae collection at the Royal Belgian Institute of Natural Sciences. Both data sets were used to investigate trends in mosquito species richness in several regions in Belgium. The relative change in distribution area of mosquito species was particularly important for species that use waste waters and used tires as larval habitats and species that recently shifted their larval habitat to artificial larval habitats. More importantly, several of these species are known as vectors of arboviruses and Plasmodium sp. and the apparent habitat shift of some of them brought these species in proximity to humans. Similar studies comparing current mosquito richness with former distribution data retrieved from voucher specimens from collections is therefore encouraged because they can generate important information concerning health risk assessment at both regional and national scale.

  7. Culicidae and Ceratopogonidae (Diptera: Nematocera inhabiting phytotelmata in Iguazú National Park, Misiones Province, subtropical Argentina

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    Raúl E. CAMPOS

    2011-01-01

    Full Text Available Se presenta una lista de las fitotelmata más comunes y los Culicidae y Ceratopogonidae que las habitan, del Parque Nacional Iguazú, Misiones, Argentina; además de observaciones biológicas y de comportamiento. Especies de Poaceae, Bromeliaceae, Apiaceae, Araceae, Urticaceae, Marantaceae, y Arecaceae, fueron identificadas como fitotelmata. Fueron reconocidas 26 especies de culícidos y nueve de Ceratopogonidae. La mayor riqueza de especies de culícidos y ceratopogónidos se registraron en el bambú Guadua chacoensis (Poaceae y en los huecos de los árboles respectivamente. Catorce especies de culícidos y tres de ceratopogónidos habitan bambúes, dos y cinco en los huecos de los árboles, siete y tres en bromelias y nueve y una en otras fitotelmata, respectivamente.

  8. Composition and Genetic Diversity of Mosquitoes (Diptera: Culicidae) on Islands and Mainland Shores of Kenya's Lakes Victoria and Baringo.

    Science.gov (United States)

    Ajamma, Yvonne Ukamaka; Villinger, Jandouwe; Omondi, David; Salifu, Daisy; Onchuru, Thomas Ogao; Njoroge, Laban; Muigai, Anne W T; Masiga, Daniel K

    2016-11-01

    The Lake Baringo and Lake Victoria regions of Kenya are associated with high seroprevalence of mosquito-transmitted arboviruses. However, molecular identification of potential mosquito vector species, including morphologically identified ones, remains scarce. To estimate the diversity, abundance, and distribution of mosquito vectors on the mainland shores and adjacent inhabited islands in these regions, we collected and morphologically identified adult and immature mosquitoes and obtained the corresponding sequence variation at cytochrome c oxidase 1 (COI) and internal transcribed spacer region 2 (ITS2) gene regions. A total of 63 species (including five subspecies) were collected from both study areas, 47 of which have previously been implicated as disease vectors. Fourteen species were found only on island sites, which are rarely included in mosquito diversity surveys. We collected more mosquitoes, yet with lower species composition, at Lake Baringo (40,229 mosquitoes, 32 species) than at Lake Victoria (22,393 mosquitoes, 54 species). Phylogenetic analysis of COI gene sequences revealed Culex perexiguus and Cx tenagius that could not be distinguished morphologically. Most Culex species clustered into a heterogeneous clade with closely related sequences, while Culex pipiens clustered into two distinct COI and ITS2 clades. These data suggest limitations in current morphological identification keys. This is the first DNA barcode report of Kenyan mosquitoes. To improve mosquito species identification, morphological identifications should be supported by their molecular data, while diversity surveys should target both adults and immatures. The diversity of native mosquito disease vectors identified in this study impacts disease transmission risks to humans and livestock. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.

  9. Comparison of automatic traps to capture mosquitoes (Diptera: Culicidae in rural areas in the tropical Atlantic rainforest

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    Ivy Luizi Rodrigues de Sa

    2013-12-01

    Full Text Available In several countries, surveillance of insect vectors is accomplished with automatic traps. This study addressed the performance of Mosquito Magnet® Independence (MMI in comparison with those of CDC with CO2 and lactic acid (CDC-A and CDC light trap (CDC-LT. The collection sites were in a rural region located in a fragment of secondary tropical Atlantic rainforest, southeastern Brazil. Limatus durhami and Limatus flavisetosus were the dominant species in the MMI, whereas Ochlerotatus scapularis was most abundant in CDC-A. Culex ribeirensis and Culex sacchettae were dominant species in the CDC-LT. Comparisons among traps were based on diversity indices. Results from the diversity analyses showed that the MMI captured a higher abundance of mosquitoes and that the species richness estimated with it was higher than with CDC-LT. Contrasting, difference between MMI and CDC-A was not statistically significant. Consequently, the latter trap seems to be both an alternative for the MMI and complementary to it for ecological studies and entomological surveillance.

  10. Comparison of automatic traps to capture mosquitoes (Diptera: Culicidae) in rural areas in the tropical Atlantic rainforest

    Science.gov (United States)

    de Sá, Ivy Luizi Rodrigues; Sallum, Maria Anice Mureb

    2013-01-01

    In several countries, surveillance of insect vectors is accomplished with automatic traps. This study addressed the performance of Mosquito Magnet® Independence (MMI) in comparison with those of CDC with CO2 and lactic acid (CDC-A) and CDC light trap (CDC-LT). The collection sites were in a rural region located in a fragment of secondary tropical Atlantic rainforest, southeastern Brazil. Limatus durhami and Limatus flavisetosus were the dominant species in the MMI, whereas Ochlerotatus scapularis was most abundant in CDC-A. Culex ribeirensis and Culex sacchettae were dominant species in the CDC-LT. Comparisons among traps were based on diversity indices. Results from the diversity analyses showed that the MMI captured a higher abundance of mosquitoes and that the species richness estimated with it was higher than with CDC-LT. Contrasting, difference between MMI and CDC-A was not statistically significant. Consequently, the latter trap seems to be both an alternative for the MMI and complementary to it for ecological studies and entomological surveillance. PMID:24402154

  11. Species Diversity, Abundance, and Host Preferences of Mosquitoes (Diptera: Culicidae) in Two Different Ecotypes of Madagascar With Recent RVFV Transmission.

    Science.gov (United States)

    Jean Jose Nepomichene, Thiery Nirina; Elissa, Nohal; Cardinale, Eric; Boyer, Sebastien

    2015-09-01

    Mosquito diversity and abundance were examined in six Madagascan villages in either arid (Toliary II district) or humid (Mampikony district) ecotypes, each with a history of Rift Valley fever virus transmission. Centers for Disease Control and Prevention light traps without CO2 (LT) placed near ruminant parks and animal-baited net trap (NT) baited with either zebu or sheep/goat were used to sample mosquitoes, on two occasions between March 2011 and October 2011. Culex tritaeniorhynchus (Giles) was the most abundant species, followed by Culex antennatus (Becker) and Anopheles squamosus/cydippis (Theobald/de Meillon). These three species comprised more than half of all mosquitoes collected. The NT captured more mosquitoes in diversity and in abundance than the LT, and also caught more individuals of each species, except for An. squamosus/cydippis. Highest diversity and abundance were observed in the humid and warm district of Mampikony. No host preference was highlighted, except for Cx. tritaeniorhynchus presenting a blood preference for zebu baits. The description of species diversity, abundance, and host preference described herein can inform the development of control measures to reduce the risk of mosquito-borne diseases in Madagascar. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Ecology of Culiseta Melanura and Other Mosquitoes (Diptera: Culicidae) from Walton County, FL, During Winter Period 2013-2014.

    Science.gov (United States)

    Burkett-Cadena, Nathan D; Bingham, Andrea M; Hunt, Brenda; Morse, Gary; Unnasch, Thomas R

    2015-09-01

    Winter ecology of putative vectors of eastern equine encephalomyelitis virus (EEEV) in northern Florida was investigated at field locations with evidence of historic EEEV winter transmission. Light traps and resting shelters were used to sample the mosquito community in the vicinity of eight sentinel flocks throughout the winter period (November-April) of 2013 and 2014 in Walton County, FL. Overall mosquito activity was relatively low, although mosquitoes were captured during each week of the study period. Mosquito activity was linked to morning temperature, and females were captured when ambient morning temperatures were quite low (1-5°C). Anopheles crucians Wiedemann, Culex erraticus (Dyar and Knab), Culex territans Walker, and Culiseta melanura (Coquillett) were the most commonly collected mosquito species (of 20 total species). Analysis of blood-engorged mosquitoes revealed a number of mosquito species feeding upon chickens, other birds, amphibians, and domestic and wild mammals. Cs. melanura fed primarily upon chickens and songbirds (Passeriformes), suggesting that this mosquito species is the likely winter vector of EEEV to sentinel chickens in northern Florida. Both resident and nonresident songbird species were fed upon, constituting 63.9 and 36.1% of total songbird meals, respectively. Our results suggest important roles for Cs. melanura and songbird hosts for the winter transmission of EEEV in northern Florida. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Using remote sensing to map larval and adult populations of Anopheles hyrcanus (Diptera: Culicidae a potential malaria vector in Southern France

    Directory of Open Access Journals (Sweden)

    Roger François

    2008-02-01

    Full Text Available Abstract Background Although malaria disappeared from southern France more than 60 years ago, suspicions of recent autochthonous transmission in the French Mediterranean coast support the idea that the area could still be subject to malaria transmission. The main potential vector of malaria in the Camargue area, the largest river delta in southern France, is the mosquito Anopheles hyrcanus (Diptera: Culicidae. In the context of recent climatic and landscape changes, the evaluation of the risk of emergence or re-emergence of such a major disease is of great importance in Europe. When assessing the risk of emergence of vector-borne diseases, it is crucial to be able to characterize the arthropod vector's spatial distribution. Given that remote sensing techniques can describe some of the environmental parameters which drive this distribution, satellite imagery or aerial photographs could be used for vector mapping. Results In this study, we propose a method to map larval and adult populations of An. hyrcanus based on environmental indices derived from high spatial resolution imagery. The analysis of the link between entomological field data on An. hyrcanus larvae and environmental indices (biotopes, distance to the nearest main productive breeding sites of this species i.e., rice fields led to the definition of a larval index, defined as the probability of observing An. hyrcanus larvae in a given site at least once over a year. Independent accuracy assessments showed a good agreement between observed and predicted values (sensitivity and specificity of the logistic regression model being 0.76 and 0.78, respectively. An adult index was derived from the larval index by averaging the larval index within a buffer around the trap location. This index was highly correlated with observed adult abundance values (Pearson r = 0.97, p An. hyrcanus larval and adult populations from the landscape indices. Conclusion This work shows that it is possible to use

  14. Repellent effect of Salvia dorisiana, S. longifolia, and S. sclarea (Lamiaceae) essential oils against the mosquito Aedes albopictus Skuse (Diptera: Culicidae).

    Science.gov (United States)

    Conti, Barbara; Benelli, Giovanni; Leonardi, Michele; Afifi, Fatma U; Cervelli, Claudio; Profeti, Raffaele; Pistelli, Luisa; Canale, Angelo

    2012-07-01

    Aedes albopictus (Diptera: Culicidae) has been one of the fastest spreading insects over the past 20 years. Its medical importance is due to the aggressive daytime human-biting behavior and the ability to vector many viruses, including dengue, LaCrosse, Eastern Equine encephalitis and West Nile viruses. In this research, the essential oils (EOs) extracted from fresh air dried leaves of Salvia dorisiana, S. longifolia, and S. sclarea (Lamiaceae) were evaluated for their repellent activity against A. albopictus by using the human-bait technique. The EOs chemical composition was also investigated, and EOs were divided in three different profiles on the basis of their chemical composition: EO with large amount of monoterpenes from S. sclarea, EO rich in oxygenated sesquiterpenes from S. dorisiana, and S. longifolia EO characterized by similar percentages of monoterpenes and sesquiterpenes. The efficacy protection from S. dorisiana, S. longifolia, and S. sclarea EOs, at dosages ranging from 0.004 to 0.4 μL cm(-2) of skin, was evaluated during 120 min of observation. Results indicated that S. dorisiana, S. longifolia, and S. sclarea EOs had a significant repellent activity (RD(50) =0.00035, 0.00049, and 0.00101 μL cm(-2), respectively), with differences in repellency rates, as a function of oil, dosage, and observation time. S. dorisiana was the most effective oil: at the two higher dosages, it gave almost complete protection (with a protective efficacy of 90.99% and 95.62%, respectively) for 90 min. The best protection time was achieved with S. dorisiana essential oil. It ranged from 9.2 to 92.4 min. Protection times of S. longifolia and S. sclarea oils ranged from 3.2 to 60 min, and from 3.6 to 64.2 min, respectively. Our findings clearly reveal that these EOs have a good repellent activity against A. albopictus, therefore they can be proposed to improve the efficacy of repellent formulations against the Asian tiger mosquito.

  15. The effects of blood feeding and exogenous supply of tryptophan on the quantities of xanthurenic acid in the salivary glands of Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Okech, Bernard; Arai, Meiji; Matsuoka, Hiroyuki

    2006-03-24

    Xanthurenic acid (XA), produced as a byproduct during the biosynthesis of insect eye pigment (ommochromes), is a strong inducer of Plasmodium gametogenesis at very low concentrations. In previous studies, it was shown that XA is present in Anopheles stephensi (Diptera: Culicidae) mosquito salivary glands and that during blood feeding the mosquitoes ingested their own saliva into the midgut. Considering these two facts together, it is therefore likely that XA is discharged with saliva during blood feeding and is swallowed into the midgut where it exerts its effect on Plasmodium gametocytes. However, the quantities of XA in the salivary glands and midgut are unknown. In this study, we used high performance liquid chromatography with electrochemical detection to detect and quantify XA in the salivary glands and midgut. Based on the results of this study, we found 0.28+/-0.05 ng of XA in the salivary glands of the mosquitoes, accounting for 10% of the total XA content in the mosquito whole body. The amounts of XA in the salivary glands reduced to 0.13+/-0.06 ng after mosquitoes ingested a blood meal. Approximately 0.05+/-0.01 ng of XA was detected in the midgut of nonblood fed An. stephensi mosquitoes. By adding synthetic tryptophan as a source of XA into larval rearing water (2 mM) or in sugar meals (10 mM), we evaluated whether XA levels in the mosquito (salivary glands, midgut, and whole body) were boosted and the subsequent effect on infectivity of Plasmodium berghei in the treated mosquito groups. A female specific increase in XA content was observed in the whole body and in the midgut of mosquito groups where tryptophan was added either in the larval water or sugar meals. However, XA in the salivary glands was not affected by tryptophan addition to larval water, and surprisingly it reduced when tryptophan was added to sugar meals. The P. berghei oocyst loads in the mosquito midguts were lower in mosquitoes fed tryptophan treated sugar meals than in mosquitoes

  16. Using remote sensing to map larval and adult populations of Anopheles hyrcanus (Diptera: Culicidae) a potential malaria vector in Southern France

    Science.gov (United States)

    Tran, Annelise; Ponçon, Nicolas; Toty, Céline; Linard, Catherine; Guis, Hélène; Ferré, Jean-Baptiste; Lo Seen, Danny; Roger, François; de la Rocque, Stéphane; Fontenille, Didier; Baldet, Thierry

    2008-01-01

    Background Although malaria disappeared from southern France more than 60 years ago, suspicions of recent autochthonous transmission in the French Mediterranean coast support the idea that the area could still be subject to malaria transmission. The main potential vector of malaria in the Camargue area, the largest river delta in southern France, is the mosquito Anopheles hyrcanus (Diptera: Culicidae). In the context of recent climatic and landscape changes, the evaluation of the risk of emergence or re-emergence of such a major disease is of great importance in Europe. When assessing the risk of emergence of vector-borne diseases, it is crucial to be able to characterize the arthropod vector's spatial distribution. Given that remote sensing techniques can describe some of the environmental parameters which drive this distribution, satellite imagery or aerial photographs could be used for vector mapping. Results In this study, we propose a method to map larval and adult populations of An. hyrcanus based on environmental indices derived from high spatial resolution imagery. The analysis of the link between entomological field data on An. hyrcanus larvae and environmental indices (biotopes, distance to the nearest main productive breeding sites of this species i.e., rice fields) led to the definition of a larval index, defined as the probability of observing An. hyrcanus larvae in a given site at least once over a year. Independent accuracy assessments showed a good agreement between observed and predicted values (sensitivity and specificity of the logistic regression model being 0.76 and 0.78, respectively). An adult index was derived from the larval index by averaging the larval index within a buffer around the trap location. This index was highly correlated with observed adult abundance values (Pearson r = 0.97, p landscape indices. Conclusion This work shows that it is possible to use high resolution satellite imagery to map malaria vector spatial distribution

  17. Microhabitats de mosquitos (Diptera, Culicidae em internódios de taquara na Mata Atlântica, Paraná, Brasil Mosquitoes microhabitats (Diptera, Culicidae in bamboo internodes in Atlantic forest, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Ana Leuch Lozovei

    Full Text Available During two consecutive years, from January 1985 to December 1986, a comparative study of mosquitoes preferences for breeding habitat was carried out in the Atlantic Forest of the Serra do Mar, Paraná State, Brazil. To achieve it, 1875 bamboo internodes aligned vertically in live green, bamboo plants Merostachys speciosa Munro and Merostachys sp. were used, in which metabolic water was exuded from the plant itself, and presenting different size/pattern holes at their lateral walls, bored by the local sylvan fauna. Another group of 1200 individual internode traps was used as comparative element, carved out with a transversal cut by a saw, filled with local stream water and held in branches at different heights in the vegetal strata nearby. At both microhabitat types, a total of 17 culicid species was registered. Culex (Microculex neglectus Lutz, 1904, Cx. (Carrollia soperi Antunes & Lane, 1937, Sabethes (Sabethes batesi Lane & Cerqueira, 1942 and Sa. (Sabethinus melanonymphe (Dyar, 1924colonized exclusively live plant internodes, while Culex (Microculex elongatus Rozeboom & Lane, 1950, Cx. (Carrollia iridescens (Lutz, 1905, Cx. (Carrollia kompi Valencia,1973and Trichoprosopon (Trichoprosopon soaresi Dyar & Knab, 1907 bred only in internode traps. The remaining nine species colonized both habitats indistinctly. Quantitatively, was detected the abundance of 60.1% at live green internodes, against 39.9% for internode traps. Concerning the different patterns of bored live internode holes, 40.3% of the total computed specimens were collected in square or rectangular holes, 31.9% in two hole internodes, one minute circular, the other wider, and the remaining 28.8% of specimens distributed in other pattern type internodes. The mosquitoes breeding at these microhabitats fall in the culicid entomofauna specialized at locating and detecting peculiar and propitious mesogen conditions for breeding purposes.

  18. First report of Coelomomyces santabrancae sp. nov. (Blastocladiomycetes: Blastocladiales) infecting mosquito larvae (Diptera: Culicidae) in central Brazil.

    Science.gov (United States)

    Rueda-Páramo, M E; Montalva, C; Arruda, W; Fernandes, É K K; Luz, C; Humber, R A

    2017-10-01

    A project from 2013 to 2017 sought to discover pathogenic fungi and oomycetes from dipteran species that are vectors of major diseases of humans and animals in central Brazil and to begin evaluating the potential of these pathogens as potential biological control agents concentrated on mosquito larvae. Some collecting sites proved to be especially productive for pathogens of naturally occurring mosquito species and for placements of healthy sentinel larvae of Aedes aegypti in various sorts of containers in a gallery forest in the Santa Branca Ecoturismo Private Reserve of Natural Patrimony (RPPN) near Terezópolis de Goiás (GO). Collections during May-April of 2016 and February 2017 yielded a few dead mosquito larvae of an undetermined Onirion sp. (Culicidae: Sabethini) whose hemocoels contained many ovoid, thick-walled, yellow-golden to golden-brown, ovoid thick-walled resistant sporangia, 38.3±4×22.8±2.3µm, decorated by numerous, closely and randomly spaced punctations of variable size and shape. These were the first indisputable collections from Brazil of any Coelomomyces species. Comparisons of the morphology of these sporangia with those of other species of Coelomomyces, confirmed that this Brazilian fungus represented a new species that is described here as Coelomomyces santabrancae. Copyright © 2017. Published by Elsevier Inc.

  19. Effect of different hosts on feeding patterns and mortality of mosquitoes (Diptera: Culicidae and their implications on parasite transmission

    Directory of Open Access Journals (Sweden)

    Eliningaya J Kweka

    2010-01-01

    Full Text Available Aim: The host-response to hematophagus insects is still an important parameter in understanding disease transmission patterns. We investigated the feeding and mortality rates of three mosquito species, namely Culex quinquefasciatus, Aedes aegypti and Anopheles arabiensis against three different hosts. Materials and Methods: Unfed three to five-day-old female mosquitoes were released in a tunnel box that had a rabbit or guinea pig or mice as a host. The feeding succession patterns of mosquitoes in different hosts were An. arabiensis, Cx. quinquefasciatus and A. aegypti. Results: Mosquito mortality rate was 54.9% for mosquitoes introduced in mice as a host, 34.3% in the Guinea pig and 10.8% for those that introduced in the rabbit. Conclusion: The presence of defensive and tolerable hosts in environment emphasizes the relevance of studying epidemiological impact of these behaviors in relation to diseases transmission.

  20. Mosquitocidal properties of Solanum trilobatum L. (Solanaceae) leaf extracts against three important human vector mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Premalatha, Selvaraj; Elumalai, Kuppusamy; Jeyasankar, Alagarmalai

    2013-11-01

    To determine the larvicidal and pupicidal activites of Solanum trilobatum (S. trilobatum) leaf extracts against Aedes aegypti (Ae. aegypti), Culex quinquefasciatus (Cx. quinquefasciatus) and Anopheles stephensi (An. stephensi). The larvicidal and pupucidal was determined at five different concentrations of 50, 100, 150, 200 and 250 ppm. Percentage of larval mortality was assessed after 48 h. Methanol extracts of S. trilobatum was found to be more susceptible against the larvae of Ae. aegypti, Cx. quinquefasciatus and An. stephensi at 250 ppm with a LC50 value of 125.43, 127.77 and 116.64 ppm respectively. Leaf methanol extracts of S. trilobatum also exhibited pupicidal and adult emergence properties. These results suggested that the leaf extracts of S. trilobatum showed potential to be used as an ideal ecofriendly approach for the control of the Ae. Aegypti, Cx. quinquefasciatus and An. stephensi. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  1. [Mosquitos (Diptera: Culicidae) in the small village where a human case of Venezuelan equine encephalitis was recorded].

    Science.gov (United States)

    Ferro, Cristina; Olano, Víctor Alberto; Ahumada, Martha; Weaver, Scott

    2008-06-01

    The enzootic focus of subtype ID of Venezuelan equine encephalitis (VEE) virus in the Central Magdalena region (central Colombia) occasionally produces human cases. The report of a VEE infection in a three-year-old girl in the small Chingalé, municipalitype of Puerto Wilches, Santander, motivated this study. The village of Chingalé was evaluated as the probable site of infection. In June 2005, mosquitoes were collected with CDC light traps in and outside of dwellings in the village. Trinidad traps were placed in nearby vegetation, and hamsters were used as sentinel animals near homes. One hundred and seven samples, consisting of 14,423 mosquitoes of 35 species were collected. The relative abundance of incriminated vectors of subtype ID of VEE, Culex (Melanoconion) pedroi and Cx. (Mel.) ocossa, was generally low (mosquitoes of the subgenus Melanoconion carried the virus into the village from a neighboring habitat.

  2. Molecular detection of Wolbachia pipientis in natural populations of mosquito vectors of Dirofilaria immitis from continental Portugal: first detection in Culex theileri.

    Science.gov (United States)

    DE Pinho Mixão, V; Mendes, A M; Maurício, I L; Calado, M M; Novo, M T; Belo, S; Almeida, A P G

    2016-09-01

    Wolbachia pipientis (Rickettsiales: Rickettsiaceae) protects mosquitoes from infections with arboviruses and parasites. However, the effect of its co-infection on vector competence for Dirofilaria immitis (Spirurida: Onchocercidae) in the wild has not been investigated. This study aimed to screen vectors of D. immitis for wPip, to characterize these, and to investigate a possible association between the occurrence of W. pipientis and that of the nematode. The presence of W. pipientis was assessed in the five mosquito potential vectors of D. immitis in Portugal. Polymerase chain reaction (PCR) products were sequenced, and wPip haplotypes were determined by PCR-restricted fragment length polymorphism (RFLP). Results showed that wPip was detected in 61.5% of Culex pipiens (Diptera: Culicidae) pools and 6.3% of Culex theileri pools. wPip 16s rRNA sequences found in Cx. theileri exactly match those from Cx. pipiens, confirming a mosquito origin, rather than a nematode origin, as some specimens were infected with D. immitis. Only wPip haplotype I was found. No association was found between the presence of wPip and D. immitis in mosquitoes and hence a role for this endosymbiont in influencing vectorial competence is yet to be identified. This study contributes to understanding of wPip distribution in mosquito populations and, to the best of the authors' knowledge, is the first report of natural infections by wPip in Cx. theileri. © 2016 The Royal Entomological Society.

  3. Effect of chlorfenapyr on cypermethrin-resistant Culex pipiens pallens Coq mosquitoes.

    Science.gov (United States)

    Yuan, J Z; Li, Q F; Huang, J B; Gao, J F

    2015-03-01

    Chlorfenapyr is a promising pyrrole insecticide with a unique mechanism of action that does not confer cross-resistance to neurotoxic insecticides. The effect of chlorfenapyr on pyrethorid-resistant Culex pipiens pallens Coq (Diptera: Culicidae) has not been fully investigated under laboratory conditions. In this study, cypermethrin-resistant C. p. pallens exhibited 376.79-fold and 395.40-fold increase in resistance to cypermethrin compared with susceptible strains after exposure for 24 and 48h, respectively. Larvae and adults were tested for susceptibility using dipping, topical, and impregnated paper methods as recommended by the WHO. No cross-resistance to chlorfenapyr was found. Increased mortality was apparent between 48 and 72h, indicating a slow rate of toxic activity. Synergism experiments with piperonyl butoxide (PBO) showed an antagonistic effect on chlorfenapyr toxicity. Mixtures of chlorfenapyr and cypermethrin could therefore provide additional benefits over either insecticide used alone. Mixtures of 5ng/ml chlorfenapyr and 500ng/ml cypermethrin exhibited a slight synergistic effect on cypermethrin-resistant mosquitoes (3.33, 6.84 and 2.34% after 24, 48 and 72h exposure, respectively. This activity was lost when the chlorfenapyr concentration was increased to 10 or 20ng/ml. Chlorfenapyr showed quite good results for pyrethroid-resistant C. p. pallens, and could improve public health by reducing the occurrence of mosquito bites and subsequently protecting against transmission of lymphatic filariasis and Japanese encephalitis. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Host-Feeding Preference of the Mosquito, Culex quinquefasciatus, in Yucatan State, Mexico

    Science.gov (United States)

    Garcia-Rejon, Julian E.; Blitvich, Bradley J.; Farfan-Ale, Jose A.; Loroño-Pino, Maria A.; Chi Chim, Wilberth A.; Flores-Flores, Luis F.; Rosado-Paredes, Elsy; Baak-Baak, Carlos; Perez-Mutul, Jose; Suarez-Solis, Victor; Fernandez-Salas, Ildefonso; Beaty, Barry J.

    2010-01-01

    Studies were conducted to determine the host-feeding preference of Culex quinquefasciatus Say (Diptera: Culicidae) in relation to the availability of human and domestic animals in the city of Merida, Yucatan State, Mexico. Mosquitoes were collected in the backyards of houses using resting wooden boxes. Collections were made five times per week from January to December 2005. DNA was extracted from engorged females and tested by PCR using universal avian- and mammalian-specific primers. DNA extracted from avian-derived blood was further analyzed by PCR using primers that differentiate among the birds of three avian orders: Passeriformes, Columbiformes and Galliformes. PCR products obtained from mammalian-derived blood were subjected to restriction enzyme digestion to differentiate between human-, dog-, cat-, pig-, and horse-derived blood meals. Overall, 82% of engorged mosquitoes had fed on birds, and 18% had fed on mammals. The most frequent vertebrate hosts were Galliformes (47.1%), Passeriformes (23.8%), Columbiformes (11.2%) birds, and dogs (8.8%). The overall human blood index was 6.7%. The overall forage ratio for humans was 0.1, indicating that humans were not a preferred host for Cx. quinquefasciatus in Merida. PMID:20578953

  5. Control of Culex quinquefasciatus in a storm drain system in Florida using attractive toxic sugar baits.

    Science.gov (United States)

    Müller, G C; Junnila, A; Qualls, W; Revay, E E; Kline, D L; Allan, S; Schlein, Y; Xue, R D

    2010-12-01

    Attractive toxic sugar baits (ATSBs) were used to control mosquitoes in the storm drains of a residential area on the outskirts of St Augustine, Florida. The drainage system was newly constructed and no mosquitoes were breeding inside it. The area covered by the storm drains was divided in half; 10 drains served as control drains and 16 drains served as experimental drains. The baits, which consisted of a mixture of brown sugar, fruit juice, green dye marker and boric acid, were presented at the entrances of the treated drains and exit traps were positioned over the drain openings and the connecting tubes leading to retention ponds. Similar baits with orange dye and without toxin were presented at the entrances of control drains. A total of 220 pupae of Culex quinquefasciatus (Diptera: Culicidae) were released in each control and toxin-treated drain, and the numbers of recovered mosquitoes were examined to determine the effectiveness of ATSBs in the storm drain system. An average of 178.2 mosquitoes exited each drain in the control area; 87.0% of these had fed on the baits and were stained orange, whereas 13.0% were unstained. In the toxin-treated drains, 83.7% of hatched females and 86.6% of hatched males were controlled by the baits. © 2010 The Authors. Medical and Veterinary Entomology © 2010 The Royal Entomological Society.

  6. The ecology and larval habitats characteristics of anopheline mosquitoes (Diptera: Culicidae) in Aligudarz County (Luristan province, western Iran).

    Science.gov (United States)

    Amani, Hamid; Yaghoobi-Ershadi, Mohammad Reza; Kassiri, Hamid

    2014-05-01

    To determine ecology and characteristics of the larval habitats of the genus Anopheles (Dipetra: Culicidae) in Aligudarz County, western Iran. This descriptive cross-sectional research was carried out to study the anopheline larvae ecology in seven rural districts, Aligudarz County, from late April to late November 1997. Larvae were captured using the dipping method. Larval breeding places characteristics were noted according to water situation (turbid or clean, stagnant or running), substrate type, site type (man-made or natural), sunlight situation, site situation (transient or permanent, with or without vegetation). A total of 9 620 3rd and 4th instar larvae of Anopheles from 115 breeding places in 22 villages were captured, which belonged to the following species: Anopheles stephensi, Anopheles d'thali, Anopheles apoci, Anopheles superpictus (forms A and B), Anopheles marterii sogdianus, Anopheles turkhodi, Anopheles maculipennis S.L and Anopheles claviger. Anopheles stephensi, Anopheles maculipennis S.L and Anopheles apoci were collected for the first time in this county. Anopheles superpictus (93.18%) was the most prevailed one and dispersed over the entire region. Larval habitats consisted of nine natural and three artificial larval habitats. The most important larval habitats were river edges (54.8%), rice fields (12.2%), and grassland (8.7%) with permanent or transient, stagnant or running and clean water, with or without vegetation, sand or mud substrate in full sunlight area. Regarding this research, river edges and rice fields are the most important breeding places of malaria vectors in Aligudarz County. It is worthy of note in larvicidal programs.

  7. Digestive Processes of Haematophagous Insects. I. A Literature Review,

    Science.gov (United States)

    INSECTS , *DIGESTIVE SYSTEM), (*ARTHROPODA, DIGESTIVE SYSTEM), ENTOMOLOGY, PHYSIOLOGY, BLOOD, INGESTION(PHYSIOLOGY), CULICIDAE, TICKS, ENZYMES, SALIVARY GLANDS, AEDES, ANOPHELES, DISEASE VECTORS, CULEX, DIPTERA

  8. Mosquito Surveillance and the First Record of the Invasive Mosquito Species Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae) in Southern Iran.

    Science.gov (United States)

    Doosti, Sara; Yaghoobi-Ershadi, Mohammad Reza; Schaffner, Francis; Moosa-Kazemi, Seyed Hassan; Akbarzadeh, Kamran; Gooya, Mohammad Mehdi; Vatandoost, Hassan; Shirzadi, Mohammad Reza; Mosta-Favi, Ehsan

    2016-08-01

    Epidemics of mosquito-borne viral infections such as dengue, chikungunya, West Nile and Rift Valley fevers in neighbouring countries and risk of introduction of exotic vectors into Iran have placed this country at a significant risk for these mosquito-borne diseases. After the first dengue case reported in Iran in 2008, active entomological surveillance of Aedes albopictus (Skuse) and Ae. aegypti (Linnaeus) were conducted in May/Jun, Sep, and Oct/Nov, 2008-2014. Based on occurrence of dengue cases and the presence of potential entry sides including ports and boarder gates, 121 sites in eight provinces were monitored for mosquito vectors. Larval collections were carried out using droppers or dippers and adult collections with CDC light traps, human landing catches, aspirator and Pyrethrum spray space catches. A total of 8,186 larvae and 3,734 adult mosquitoes were collected belonging to 23 Culicinae species, including 13 of the genus Culex, 1 Culiseta, 1 Uranotaenia, and 8 of the genus Aedes. Five Aedes albopictus larvae were identified from the Sistan & Baluchestan province bordering Pakistan in 2009. In 2013, seven Ae. albopictus adult mosquitoes were also collected in a coastal locality near the city of Chabahar in the same province. The detection of larvae and adults of this species in different parts of this province reveal its probable establishment in southeast Iran, which has implications for public health and requires active entomological surveillance as well as the implementation of vector control to prevent the further spread of this critical vector.

  9. West Nile virus surveillance: A simple method for verifying the integrity of RNA in mosquito (Diptera: Culicidae) pools.

    Science.gov (United States)

    Hoffmann, Peter R; Woodrow, Robert J; Calimlim, Precilia S; Sciulli, Rebecca; Effler, Paul V; Miyamoto, Vernon; Imrie, Allison; Yanagihara, Richard; Nerurkar, Vivek R

    2004-07-01

    In a West Nile virus (WNV) -free ecosystem, it is essential to verify the integrity of RNA before concluding that RNA extracted from mosquito specimens is negative for WNV gene sequences. The primary objective of our study was to develop a rapid molecular assay to rapidly screen mosquitoes for the presence of 18S RNA and WNV gene sequences. Mosquitoes, collected from multiple sites on the island of O'ahu, were pooled into groups of 1-50 mosquitoes according to capture site, date, and species. Using primer design software and the GenBank database, generic oligonucleotide primer pairs were designed to amplify mosquito18S rRNA gene sequences from different species. RNA was extracted from mosquito pools, and reverse transcriptase-polymerase chain reaction (RT-PCR) was performed for the presence of mosquito18S rRNA and WNV gene sequences. Three of the seven primer pairs successfully detected 18S rRNA sequences for both Aedes and Culex by RT-PCR, and one primer pair successfully amplified 18S rRNA sequences for 15 different mosquito species. All 64 mosquito pools from 10 different sites on the island of Oahu, Hawaii, were negative for WNV nonstructural protein-5 gene sequences. This simple, one-step RT-PCR method for screening mosquito pools for arboviruses will become an increasingly valuable tool as WNV becomes endemic throughout the Americas.

  10. Mosquito (Diptera: Culicidae) assemblages associated with Nidularium and Vriesea bromeliads in Serra do Mar, Atlantic Forest, Brazil

    Science.gov (United States)

    2012-01-01

    Background The most substantial and best preserved area of Atlantic Forest is within the biogeographical sub-region of Serra do Mar. The topographic complexity of the region creates a diverse array of microclimates, which can affect species distribution and diversity inside the forest. Given that Atlantic Forest includes highly heterogeneous environments, a diverse and medically important Culicidae assemblage, and possible species co-occurrence, we evaluated mosquito assemblages from bromeliad phytotelmata in Serra do Mar (southeastern Brazil). Methods Larvae and pupae were collected monthly from Nidularium and Vriesea bromeliads between July 2008 and June 2009. Collection sites were divided into landscape categories (lowland, hillslope and hilltop) based on elevation and slope. Correlations between bromeliad mosquito assemblage and environmental variables were assessed using multivariate redundancy analysis. Differences in species diversity between bromeliads within each category of elevation were explored using the Renyi diversity index. Univariate binary logistic regression analyses were used to assess species co-occurrence. Results A total of 2,024 mosquitoes belonging to 22 species were collected. Landscape categories (pseudo-F value = 1.89, p = 0.04), bromeliad water volume (pseudo-F = 2.99, p = 0.03) and bromeliad fullness (Pseudo-F = 4.47, p mosquito assemblage structure. Renyi diversity index show that lowland possesses the highest diversity indices. The presence of An. homunculus was associated with Cx. ocellatus and the presence of An. cruzii was associated with Cx. neglectus, Cx. inimitabilis fuscatus and Cx. worontzowi. Anopheles cruzii and An. homunculus were taken from the same bromeliad, however, the co-occurrence between those two species was not statistically significant. Conclusions One of the main findings of our study was that differences in species among mosquito assemblages were influenced by landscape characteristics. The bromeliad factor

  11. Additions to the aquatic diptera (Chaoboridae, Chironomidae, Culicidae, Tabanidae, Tipulidae) fauna of the White River National Wildlife Refuge, Arkansas

    Science.gov (United States)

    Chordas, Stephen W.; Hudson, Patrick L.; Chapman, Eric G.

    2004-01-01

    The dipteran fauna of Arkansas is generally poorly known. A previous study of the Aquatic macroinvertebrates of the White River National Wildlife Refuge, the largest refuge in Arkansas, reported only 12 diptera taxa out of 219 taxa collected (Chordas et al., 1996). Most of the dipterans from this study were identified only to the family level. The family Chironomidae is a large, diverse group and was predicted to be much more diverse in the refuge than indicated by previous studies. In this study, Chironomidae were targeted, with other aquatic or semiaquatic dipterans also retained, in collections designed to better define the dipteran fauna of the White River National Wildlife Refuge. Adult dipterans were collected from 22 sites within the refuge using sweep-nets, two types of blacklight traps, and lighted fan traps in June of 2001. Specimens from previous studies were retrieved and identified to the lowest possible taxonomic level. A total of 4,917 specimens representing 122 taxa was collected. The 122 taxa were comprised of the following: two chaoborids, 83 chironomids, 15 culicids, nine tabanids, and 13 tipulids. Of these, 46 species are new state records for Arkansas. Nine undescribed species of chironomids were collected, and eight species records represent significant range extensions.

  12. Survival of diurnally sub periodic Wuchereria bancrofti in Downsiomyia nivea (Diptera: Culicidae: a density dependent factor from Andaman & Nicobar Islands

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    A N Shriram

    2014-01-01

    Full Text Available Background & objectives: In India, diurnally sub periodic Wuchereria bancrofti transmitted by Downsiomyia nivea is prevalent only in the Nicobar district of Andaman and Nicobar Islands. The ongoing LF elimination programme aims at transmission interruption by bringing down the microfilarie (mf load in the community, which has implication on the parasite load in mosquito vector. Therefore, understanding density dependent constraints on transmission assumes significance from control perspective. The present study was undertaken in Teressa Island to understand the density dependent parasite mortality and survival probability of the parasite Do. nivea. Methods: The entomological data collected from Teressa Island, endemic for the diurnally sub periodic form of W. bancrofti were used to examine the parasite loss and its survival up to infectivity. Patterns of parasite distribution in Do. nivea were examined. Results: Distribution patterns of microfilariae were found to be over dispersed in Do. nivea. The later stages of the parasite in the vector were randomly distributed. Distribution pattern of various filarial larval stages suggested that the loss of parasites occurred as development progressed and was maximal between the first and second stages. Further, both the prevalence of infection and the degree of parasite aggregation in the vector population have fallen significantly with development of parasite stage. Interpretation & conclusions: Results indicate the operation of parasite density dependent mortality of vectors or parasite loss or combination of both. The present study with Aedes transmitted filariasis conducted before launching LF elimination programme in the study area indicates a comparable level of parasite regulation in the vector which has similar implications on the transmission threshold. Thus, the consideration of Aedes with Culex in deriving the critical level of antigen positive for making decisions on cessation of mass drug

  13. Impact of an Alien Invasive Shrub on Ecology of Native and Alien Invasive Mosquito Species (Diptera: Culicidae).

    Science.gov (United States)

    Muturi, Ephantus J; Gardner, Allison M; Bara, Jeffrey J

    2015-10-01

    We examined how leaf litter of alien invasive honeysuckle (Lonicera maackii Rupr.) either alone or in combination with leaf litter of one of two native tree species, sugar maple (Acer saccharum Marshall) and northern red oak (Quercus rubra L.), affects the ecology of Culex restuans Theobald, Ochlerotatus triseriatus Say, and Ochlerotatus japonicus Theobald. Experimental mesocosms containing single species litter or a mixture of honeysuckle and one of two native tree species litter were established at South Farms and Trelease Woods study sites in Urbana, IL, and examined for their effect on 1) oviposition site selection by the three mosquito species, and 2) adult production and body size of Oc. triseriatus and Oc. japonicus. There were no significant effects of study site and leaf treatment on Oc. japonicus and Oc. triseriatus oviposition preference and adult production. In contrast, significantly more Cx. restuans eggs rafts were collected at South Farms relative to Trelease Woods and in honeysuckle litter relative to native tree species litter. Significantly larger adult females of Oc. japonicus and Oc. triseriatus were collected at South Farms relative to Trelease Woods and in honeysuckle litter relative to native tree species litter. Combining honeysuckle litter with native tree species litter had additive effects on Cx. restuans oviposition preference and Oc. japonicus and Oc. triseriatus body size, with the exception of honeysuckle and northern red oak litter combination, which had antagonistic effects on Oc. triseriatus body size. We conclude that input of honeysuckle litter into container aquatic habitats may alter the life history traits of vector mosquito species. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. A Review of the Systematics and a Proposed Scheme of Internal Classification of the New World Subgenus Melanoconion of Culex (Diptera, Culicidae)

    Science.gov (United States)

    1982-01-01

    only, scales absent. Pleural integument usually slightly paler or concolorous with scutum, sometimes pale white or yellow, contrasting with that of...rarely entirely dark scaled. FEMALE CIBAJZIAL ARMATURE. As figured for atratus (Fig. 3). Cibarial dome triangular or ovoid, dark-pigmented and...yells pleural integument, the general facies, the relatively sparse long setae of the flagellar whorls, the type of decumbent scales on the vertex and

  15. Medical Entomology Studies - III. A Revision of the Subgenus Culex in the Oriental Region (Diptera: Culicidae) (Contributions of the American Entomological Institute. Volume 12, Number 2)

    Science.gov (United States)

    1976-01-01

    S. W. ; 4d, 5?, 1 1, 3 lp (P. J. Barraud; H. Cogill). PAKISTAN. Lahore; 1 L (J. Maldonado , Sept. 1957). Additional records from the literature...artificial containers such as canoes , boats, cement tanks, jars, cans, etc. in the vicinity of sea beaches, harbors or piers in populated areas. The...NEPAL. Khatmandu; 1 L (J. Maldonado , 1958). TIBET. Yatung; 2d. INDIA. Western Hima,?uyas: Kasauli; Durhampur; Assam: Tezpur; Ledo; Dibrugarh

  16. Catalog and Illustrated Review of the Subgenus Melanoconion of Culex (Diptera: Culicidae) (Contributions of the American Entomological Institute. Volume 27, Number 2, 1992)

    Science.gov (United States)

    1992-01-01

    de Entomologia Taxonomica, Division de Endemias Rurales, Maracay, Venezuela Section de Entomologia, Departamento de Parasitologia y Microbiologia ...Paulo, Brazil Faculdade de Saude Publica, Universidade de Sao Paulo, Brazil Instituto National de Microbiologia , Carlos G. Malbran, Buenos Aires

  17. Contributions of the American Entomological Institute. Volume 27. Number 2. 1992. Catalog and Illustrated Review of the Subgenus Melanoconion of Culex (Diptera: Culicidae)

    Science.gov (United States)

    1992-01-01

    Departamento de Parasitologia y Microbiologia , Escuela de Medicina, Universidad de Oriente, Ciudad Bolivar, Venezuela FMRP Departamento de Parasitologia...de Microbiologia , Carlos G. Malbran, Buenos Aires, Argentina IOC Instituto Oswaldo Cruz, Rio de Janeiro, Brazil ITH Instituut voor Tropische Hygiene en

  18. The Identity of Culex (Melanoconion) taeniopus Dyar and Knab and Related Species with Notes on the Synonymy and Description of a New Species (Diptera, Culicidae)

    Science.gov (United States)

    1980-01-01

    821774, J. F. Reinert (No. 107 136), 5 9 (USNM). S&I PauZo: Iguape, Porto de Ribeira , 17 Mr 76, 0. S. Lopes, 1 d (USNM). TAXONOMIC DISCUSSION. As...pupal, 12 larval). MEXI co. Il’abasco: Cardenas, "Colegio Superior de Agricultura Tropical", 20 mm, 15 Jul 70, D. & K. Schroeder (MEX 564), 2 9 (USNM...Marinkelle (COM 595), 1 Q (USNM). ECUADOR. Nape, Coca: Apr-May 65, L. E. Pena G. (ECU 8, 91), 1 d, 17 9 (USNM). EsmeraZdas: San Lorenzo, 14-18 Aug 72, M

  19. Effects of extract of soapnut Sapindus emarginatus on esterases and phosphatases of the vector mosquito, Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Koodalingam, Arunagirinathan; Mullainadhan, Periasamy; Arumugam, Munusamy

    2011-04-01

    Our earlier investigations with kernels from the soapnut Sapindus emarginatus revealed it as a new source of botanical biocide with potent antimosquito activity, as evident from the proven unique ability of the aqueous kernel extract to kill all the developmental stages of three important vector mosquito species, Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. This extract was also found to be safe for two non-target aquatic insects. As a sequel to these findings, we have further examined quantitative and qualitative changes in total proteins, esterases, and phosphatases in whole body homogenates of fourth instar larvae and pupae of A. aegypti exposed to this extract at an appropriate threshold time for its lethal effect to gain insights into the impact of the botanical biocide on biochemical characteristics of the target vector mosquito at two distinct developmental stages. The profiles of proteins, esterases (acetylcholinesterse, α- and β-carboxylesterases), and phosphatases (acid and alkaline) exhibited distinct patterns of variation during normal development of fourth instar larvae and pupae, indicating intrinsic difference in biochemical features between these two developmental stages of A. aegypti. Upon exposure of the larvae to the extract, significant reduction in the activities of acetylcholinesterse, β-carboxylesterase, and acid phosphatases were recorded, whereas the total proteins, α-carboxylesterase and alkaline phosphatase activities were unaffected. By contrast, only alkaline phosphatase activity was significantly affected in pupae exposed to the extract. Analysis of these enzymes in native PAGE revealed that they exist in isoforms in both the larvae and pupae. The alterations in the levels of enzymatic activities observed from the quantitative assays of various enzymes were reflected by the respective zymograms with perceptible differences in the intensity and the number of bands detected especially with β-carboxylesterase, acid

  20. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 3- Survey of adult stages at the rice irrigation system and the emergence of Anopheles albitarsis in South-Eastern, Brazil

    Directory of Open Access Journals (Sweden)

    Forattini Oswaldo Paulo

    1993-01-01

    Full Text Available A study of adult Culicidae ecology was carried out from January 1992 through January 1993 at the rice irrigation system of the Ribeira Valley Experimental Station. The adaptation of Anopheles albitarsis to the anthropic environment became evident through the adult collections made at its various habitats represented by the irrigation system and the edge of the residual pond, as well as at those made within the local patchy residual woods. Other potential disease vectors were prevalent in the irrigated system too. There were Aedes scapularis, Culex nigripalpus and Cx. ribeirensis that were collected at various habitats. Remarkable differences among their prevalences were obtained such as between the natural forest and anthropic environments. In the former An. albitarsis was practically non-existent, thus suggesting that it might be considered as eusynathropic. As the populations of other species seemed to increase in the anthropic environment, they may be regarded as hemisynanthropes. Observations suggest the hypothesis that the development of irrigated land may be a factor in the emergence of An. albitarsis, and some other species, as well as the possibility of an increase in the transmission of mosquito-borne diseases such as malaria.

  1. Dynamics of the control of Aedes (Stegomyia aegypti Linnaeus (Diptera, Culicidae by Bacillus thuringiensis var israelensis, related with temperature, density and concentration of insecticide Dinâmica do controle de Aedes (Stegomyia aegypti Linnaeus, (Diptera, Culicidae por Bacillus thuringiensis var israelensis, relacionada com a temperatura, densidade e concentração do inseticida

    Directory of Open Access Journals (Sweden)

    Jonny E. Duque L

    2006-12-01

    Full Text Available The dynamics of the control of Aedes (Stegomyia aegypti Linnaeus, (Diptera, Culicidae by Bacillus thuringiensis var israelensis has been related with the temperature, density and concentration of the insecticide. A mathematical model for biological control of Aedes aegypti with Bacillus thuringiensis var israelensis (Bti was constructed by using data from the literature regarding the biology of the vector. The life cycle was described by differential equations. Lethal concentrations (LC50 and LC95 of Bti were determined in the laboratory under different experimental conditions. Temperature, colony, larvae density and bioinsecticide concentration presented marked differences in the analysis of the whole set of variables; although when analyzed individually, only the temperature and concentration showed changes. The simulations indicated an inverse relationship between temperature and mosquito population, nonetheless, faster growth of populations is reached at higher temperatures. As conclusion, the model suggests the use of integrated control strategies for immature and adult mosquitoes in order to achieve a reduction of Aedes aegypti.Foi elaborado um modelo matemático do controle biológico de Aedes aegypti com foco em Bacillus thuringiensis var israelensis (Bti. Na construção do modelo foram utilizados dados da literatura sobre a biologia do vetor, no qual o ciclo de vida foi descrito através de equações diferenciais. As concentrações letais (CL50 e CL95 do Bti foram determinadas no laboratório sob diferentes condições experimentais. As variáveis temperatura, colônia, densidade de larvas e concentração do bioinseticida acusaram diferenças significativas quando analisadas no modelo geral, porém quando analisadas individualmente, apenas a temperatura e concentração apresentaram diferenças. As simulações do modelo indicam que a temperatura afeta inversamente a produção de indivíduos e que os pontos máximos de produ

  2. Preferências alimentares e domiciliação de mosquitos Culicidae no Vale do Ribeira, São Paulo, Brasil, com especial referência a Aedes scapularis e a Culex (Melanoconion Feeding preferences and domiciliation of Culicidae mosquitoes in the Ribeira Valley, S. Paulo State, Brazil, with particular reference to Aedes scapularis and Culex (Melanoconion

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1989-02-01

    Full Text Available Apresentam-se novos dados sobre a identificação do sangue ingerido por culicídeos ingurgitados e coletados em quatro localidades do Vale do Ribeira, Estado de São Paulo (Brasil, no período de fevereiro a novembro de 1986, e que já tinham sido sede de observações anteriores. São fornecidos dados sobre a distribuição de algumas espécies relacionadas ao tipo de ambiente. Focalizam-se Ae. scapularis e representantes de Culex (Melanoconion, principalmente Cx. ribeirensis e Cx. sacchettae. Foi possível a identificação de 651 repastos sangüíneos. Confirmou-se a preferência de Ae. scapularis por mamíferos de grande porte representados por bovinos, eqüinos e o próprio homem, tendo reagido a todos os anti-soros testados, com exceção do correspondente a animais de sangue frio representados por anfíbio. Cx. ribeirensis revelou resultados que sugerem possível preferência por mamíferos. As duas espécies supracitadas mostram tendência nítida para adaptação ao ambiente modificado pelo homem e capacidade de evolução de seus hábitos de possível domiciliação. Quanto aos outros culicídeos, as coletas de An. bellator, An. cruzii e Cq. chrysonotum limitaram-se à isca humana que a segunda dessas espécies rendeu 31,6% do total de fêmeas capturadas.New results on blood-meal identification and the environmental distribution of mosquitoes collected in four different Ribeira Valley (S. Paulo State, Brazil environments, during the period February to November 1986, are presented. Sources of 651 blood-meals were identified. The preference of Ae. scapularis for large mammals, chiefly cattle, horse and even man, was confirmed. Data suggests that a similar behavioral pattern is presented by Cx. ribeirensis. Both mosquitoes seem to be strongly attracted by peridomiciliar blood sources represented by domestic animals sheltered in that environment. Nevertheless, the female of Ae. scapularis females may use the extradomiciliary environment

  3. The influence of the area of the Serra da Mesa Hydroelectric Plant, State of Goiás, on the frequency and diversity of anophelines (Diptera: Culicidae: a study on the effect of a reservoir

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    Vanessa Melandri

    2015-02-01

    Full Text Available INTRODUCTION: Bioecological aspects of anophelines (Diptera: Culicidae near areas under the direct influence of the hydroelectric plant reservoir of Serra da Mesa in Goiás, Brazil, were analyzed. METHODS: Samples were collected at the surrounding dam area during the phases before and after reservoir impoundment. The influence of climatic and environmental factors on the occurrence of Anopheles darlingi, Anopheles albitarsis, Anopheles triannulatus, Anopheles oswaldoi and Anopheles evansae was assessed using Pearson's correlations with indicators for richness and diversity as well as the index of species abundance (ISA and the standardized index of species abundance (SISA. RESULTS: The highest anopheline density occurred during the phase after filling the tank; however, no direct correlation with the climatic factors was observed during this stage. The reservoir formation determined the incidence of the anopheline species. An. darlingi was the predominant species (SISA = 1.00. CONCLUSIONS: The significant difference (p < 0.05 observed between the species incidence during the different reservoir phases demonstrates the environmental effect of the reservoir on anophelines.

  4. Synthesis of eco-friendly silver nanoparticles from Morinda tinctoria leaf extract and its larvicidal activity against Culex quinquefasciatus.

    Science.gov (United States)

    Kumar, K Ramesh; Nattuthurai, N; Gopinath, Ponraj; Mariappan, Tirupathi

    2015-02-01

    Mosquitoes are the major vector for the transmission of malaria, dengue fever, yellow fever, filariasis, chikungunya and Japanese encephalitis, and they accounted for global mortality and morbidity with increased resistance to common insecticides. The aim of this study was to investigate the larvicidal potential of the acetone leaf extracts of Morinda tinctoria and synthesized silver nanoparticles against third instar larvae of Culex quinquefasciatus Say (Diptera: Culicidae). Nanoparticles are being used in many commercial applications. It was found that aqueous silver ions can be reduced by aqueous extract of plant parts to generate extremely stable silver nanoparticles in water. Synthesized AgNPs were characterized by ultraviolet-visible (UV-vis) spectroscopy, Atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FT-IR) analysis. The synthesized silver nanoparticles have also been tested against the third instar larvae of C. quinquefasciatus. The leaf extract and the AgNPs high mortality values were 50 % lethal concentration (LC50) = 8.088 and 1.442 ppm against C. quinquefasciatus, respectively. The results recorded from ultraviolet-visible spectroscopy, atomic force microscopy and Fourier transform infrared spectroscopy support the biosynthesis and characterization of silver nanoparticles. These results suggest that the leaf extract of M. tinctoria and synthesis of AgNPs have the potential to be used as an ideal eco-friendly approach for the control of C. quinquefasciatus. By this approach, it is suggestive that this rapid synthesis of nanoparticles would be proper for developing a biological process for mosquito control.

  5. Preferência por hospedeiro e estratificação de Culicidae (Diptera em área de remanescente florestal do Parque Regional do Iguaçu, Curitiba, Paraná, Brasil Host preference and Culicidae stratification in area of degradated inside forest of Regional do Iguaçu Park, Curitiba, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Ana Cristina Tissot

    2004-12-01

    Full Text Available A investigação das populações de Culicidae em áreas de remanescentes florestais inseridas em área urbana, podem fornecer subsídios para compreensão dos processos de utilização de habitats apresentando diferentes graus de interferência antrópica. Foram investigadas espécies potencialmente zoofílicas durante o período vespertino no interior de remanescente florestal, no espaço urbano de Curitiba, Paraná. Durante o período de setembro de 2000 a junho de 2001, foram realizadas cinco coletas por estação, com auxílio de armadilhas CDC-M instaladas em dois estratos verticais, a 1,5 m do solo e na copa das árvores (6 m. Como iscas foram utilizados mamíferos Cavia porcellus (Linnaeus, 1758 (Rodentia, Cavidae e aves Nothura maculosa (Temminck, 1815 (Tinamiformes, Tinamidae em cada um dos estratos, com revezamento das iscas animais. As armadilhas foram operadas no intervalo horário das 16:00 às 20:00 h, sendo retiradas amostras a cada intervalo de 30 minutos. Em 60 horas de operação das armadilhas CDC-M, foram capturados 1.407 exemplares de Culicidae, sendo 1.143 espécies identificadas, distribuídas em nove gêneros e 13 espécies. As espécies mais freqüentes foram Mansonia(Mansonia fonsecai (Pinto, 1932 e Mansonia (Mansonia pessoai (Barreto e Coutinho, 1944, destaca-se também a ocorrência de: Ochlerotatus (Ochlerotatus scapularis (Rondani, 1848; Psorophora (Janthinosoma ferox (Humboldt, 1819 e Aedes (Stegomyia albopictus (Skuse, 1894. Na área foram detectadas a presença de espécies com graus variados de importância epidemiológica e com tendência a explorar ambientes exófilos, florestais e peridomiciliares.Parks and plazas (green areas or vegetation islands within urban areas can provide conditions for the development of populations of mosquitoes, many species of which are very adaptable to a variety of environments. The species of mosquitoes in the family Culicidae with animal hosts, in a vegetation island within an

  6. Daya Saing Kawin Nyamuk Jantan Steril (Culex quinquefasciatus Skala Laboratorium: Studi Awal Penggunaan Teknik Serangga Mandul dalam Pengendalian Vektor Filariasis Limfatik di Kota Pekalongan

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    Tri Ramadhani

    2017-07-01

    Full Text Available ABSTRACT Culex quinquefasciatus is the main vector of limfatic filariasis in Pekalongan City. Sterile Insect Tehnique could be an alternative vector control efforts to eliminate filariasis. The success of this technique is depend on the ability of laboratory-reared sterile males with the wild-type females. Indicator of SIT Aplication is determined by the value of the mating competitiveness and sterility to Culex quinquefasciatus (Diptera:Culicidae. The design of the research is an experimental. Gamma irradiation on the pupae (age . 15 hours with the  doses of 0 Gy, 60 Gy, 65 Gy,70 Gy, 75 Gy and 80 Gy in BATAN Jakarta. Male mosquitoes which emerged from the pupa then matting with a normal female. This research observed the mean  of females laying eggs ,fecundity, fertility and  mating competitiveness. This experimental research was conducted in the laboratory and the data were analyzed by ANOVA.The result showed that irradiation at the trial doses had an effect on fertility of Culex quinquefasciatus, but not  had significant effect on  fecundity and mating competitiveness . A dose of 70 Gy is the optimum dose with a fertility rate of 1.8% (sterility 98.2% and C indexs 0,568 can be recommended for futher  semi field assays. The number of sterile males were six times compared with the wild population to increase the chances of  mating with wild-type females. Culex quinquefasciatus merupakan vektor utama filiriasis limfatik di Kota Pekalongan. Teknik Serangga Mandul dapat menjadi alternatif upaya pengendalian vektor filariasis. Keberhasilan teknik ini tergantung kemampuan jantan mandul untuk kawin dengan betina alam di laboratorium. Indikator aplikasi Teknik Serangga Mandul (TSM ditentukan dengan nilai daya saing kawin dan sterilitas. Desain penelitian yang digunakan adalah eksperimental. Nyamuk Culex quinquefasciatus berasal dari galur lokal kota Pekalongan. Iradiasi gamma pada pupa (umur >15 jam dengan dosis uji 0,60,65,70,75 dan 80 Gy di

  7. The Female Cibarial Armature of New World Culex, Subgenus Melanoconion and Related Subgenera with Notes on this Character in Subgenera Culex, Lutzia and Neoculex and Genera Galindomyia and Deinocerites (Diptera: Culicidae)

    Science.gov (United States)

    1978-01-01

    Peru ). deeZarator Dyar Subgenus lVeo&!ex: arixonensis Bohart (USA-Arizona), derivator Dyar and Knab (Costa Rica), territans Walker (USA-Maryland...apparently characteris- tic of aZbir,ensis. (d) batesi subtype (Fig. 3E). This subtype is apparently distinc- tive of batesi. The cibarial teeth...in the spissipes subtype (spissipes, eprmastasis, opisthopus, por- tesi , taeniopus and vomerifer) based on the cibarial armature as shown here and

  8. Diptera Community In The Littoral Zone Of A North East Arid Zone ...

    African Journals Online (AJOL)

    Maiduguri, Nigeria, were studied between January and June 2002. Dipteran samples were collected every 2 weeks from five different stations. Five groups of diptera organisms simulidae, chironomidae, centrapogo nidae, culicidae and chaoboridae were found in analyzable numbers. The diptera assemblage was ...

  9. Morfología y citoquímica de cultivos celulares de Aedes aegypti (Diptera: Culicidae y susceptibilidad a Leishmania panamensis (Kinetoplastida: Trypanosomatidae

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    Alfonso Arturo Miranda H

    2008-06-01

    Full Text Available La primera línea celular de Aedes aegypti fue establecida por Grace en 1966 y desde entonces se han utilizado para el estudio de virus, bacterias y parásitos. En el presente trabajo se describen, por primera vez, algunas características citoquímicas de los cultivos celulares de A. aegypti, infectados con la cepa (MHOM/CO/87CL412 de Leishmania panamensis. También se realizó un estudio morfológico de las células del cultivo. Se observaron 30 células pequeñas con apariencia fibrolastoide de 10.84±2.54 µm de largo y 5.31±1.26 µm de ancho; otras 30 presentaron apariencia epitelioide con 23.04±4.00 µm de largo y 13.96±3.70 µm de ancho; éstas últimas predominaron sobre las de apariencia fibroblastoide. De 113 células, un 7.08%, presentaron abundantes gránulos citoplasmáticos positivos con la coloración de PAS, indicando presencia de polisacáridos. La prueba de peroxidasa dio un resultado negativo. El mayor porcentaje de infección (18.90%, de un total de 101 células, se presentó el día 6. Ultraestructuralmente, las células presentaron un citoplasma con aspecto vacuolado; algunas contenían parásitos, otras material fibrilar y otras estaban vacías. Los resultados indican que los cultivos celulares de A. aegypti pueden ser infectados por L. panamensis y mantener dicho proceso por aproximadamente una semana.Morphology and cytochemistry of Aedes aegypti’s cell cultures (Diptera: Culicidae and susceptibility to Leishmania panamensis (Kinetoplastida: Trypanosomatidae. The first cellular line of Aedes aegypti was developed by Grace in 1966; afterwards, other cellular lines of this species have been generated. These have been used for the study of pathogenic organisms like viruses, bacteria and parasites, which demonstrates their importance in biomedical applications. This research describes, for the first time, some cytochemical characteristics of A. aegypti cell cultures, that were infected with (MHOM/CO/87CL412 strain of

  10. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 3- Survey of adult stages at the rice irrigation system and the emergence of Anopheles albitarsis in South-Eastern, Brazil Estudos sobre mosquitos (Diptera: Culicidae e ambiente antrópico: 3 - Coleta de formas adultas no sistema de irrigação artificial para cultivo de arroz e emergência de Anopheles albitarsis na região sudeste do Brasil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1993-10-01

    Full Text Available A study of adult Culicidae ecology was carried out from January 1992 through January 1993 at the rice irrigation system of the Ribeira Valley Experimental Station. The adaptation of Anopheles albitarsis to the anthropic environment became evident through the adult collections made at its various habitats represented by the irrigation system and the edge of the residual pond, as well as at those made within the local patchy residual woods. Other potential disease vectors were prevalent in the irrigated system too. There were Aedes scapularis, Culex nigripalpus and Cx. ribeirensis that were collected at various habitats. Remarkable differences among their prevalences were obtained such as between the natural forest and anthropic environments. In the former An. albitarsis was practically non-existent, thus suggesting that it might be considered as eusynathropic. As the populations of other species seemed to increase in the anthropic environment, they may be regarded as hemisynanthropes. Observations suggest the hypothesis that the development of irrigated land may be a factor in the emergence of An. albitarsis, and some other species, as well as the possibility of an increase in the transmission of mosquito-borne diseases such as malaria.Relatam-se os resultados obtidos com a coleta regular de Culicidae adultos no período de janeiro de 1992 a Janeiro de 1993, levadas a efeito no sistema artificialmente irrigado da Estação Experimental do Vale do Ribeira, SP -Brasil. Evidenciou-se a emergência de Anopheles albitarsis como uma das espécies de mosquitos prevalentes no sistema irrigado. Esse aspecto, acrescido da sua prática ausência no meio natural primitivo ou mesmo nas matas residuais locais, levou à hipótese de se tratar de culicídeo eusinantrópico. As condições artificiais aparentemente favoreceram também Aedes scapularis, Culex nigripalpus e Cx. ribeirensis. A comparação das biodiversidades encontradas nos ambientes, antrópico e

  11. Mosquitos (Diptera: Culicidae en el caserío de Chingalé, Santander, donde se registró un caso humano de encefalitis equina venezolana

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    María Cristina Ferro

    2008-06-01

    Conclusiones. La niña pudo infectarse en su casa o cerca de ella, aunque el ciclo epidemiológico del virus no tiene lugar en el casco urbano de Chingalé. Posiblemente ocurre en un lugar cercano y Culex (Melanoconion infectados llevan el virus al caserío, en donde algunos mosquitos incursionaron a alimentarse.

  12. Abundance and Bloodfeeding Patterns of Mosquitoes (Diptera: Culicidae) in an Oak Woodland on the Eastern Slope of the Northern Coast Range of California.

    Science.gov (United States)

    Thiemann, Tara C; Woodward, David L; Fang, Ying; Ryan, Bonnie M; Nelms, Brittany M; Scott, Jamesina J; Reisen, William K

    2017-09-01

    The abundance and bloodfeeding patterns of mosquitoes was studied from 2008 to 2010 at an 18 ha. oak woodland in Lake County, CA. Host-seeking females were collected weekly from sunset to sunrise by paired dry-ice-baited CDC style traps, whereas resting females were aspirated from paired walk-in red boxes. Sequences of the COI gene amplified from bloodmeals from engorged resting females were used to identify the bloodmeal hosts. Aedes sierrensis (Ludlow) and Aedes increpitus Dyar complex mosquitoes were univoltine, although the timing of emergence and abundance varied temporally and seemed weather dependent. Abundance of both Anopheles franciscanus McCracken and Anopheles freeborni Aitken peaked in mid to late summer. Females of both genera bloodfed primarily on mule deer and black-tailed jackrabbits, and few fed on either dogs or humans that were consistently present within the woodland. In contrast, multivoltine Culex tarsalis Coquillett and Culex stigmatosoma Dyar were abundant throughout summer, especially from July to September. Both Culex species bloodfed on a wide variety of avian hosts, with most bloodmeals originating from California scrub-jay, wild turkey, oak titmouse, and house finch. Culex tarsalis fed on proportionately more mammals as summer progressed, peaking at 33% in September. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Influência do período de quiescência dos ovos sobre o ciclo de vida de Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae em condições de laboratório

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    Silva Heloisa Helena Garcia da

    1999-01-01

    Full Text Available Estudou-se a influência do período de quiescência dos ovos no ciclo de vida de Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae em condições de laboratório, na busca de informações que possam melhorar o direcionamento das ações de controle, pois sabe-se que o ovo é a forma mais resistente do ciclo biológico, possibilitando ao mosquito ampla sobrevida, devido à resistência às adversidades climáticas. Os experimentos foram realizados numa câmara biológica, mantida à temperatura de 28 ± 1oC, com umidade relativa de 80 ± 5% e fotofase de 12 horas. Apresentam-se os dados da influência de diferentes períodos de quiescência sobre a eclosão das larvas, desenvolvimento larval e pupal, ciclo evolutivo. Verificou-se o efeito altamente significativo do período de quiescência na eclosão das larvas. O período de quiescência não influenciou nas durações dos períodos de incubação, larval e pupal. Constatou-se que ovos de um mesmo período de quiescência apresentaram períodos de incubação estatisticamente diferentes entre si. As larvas eclodiam em grupos, definidos pela incubação, e este efeito de grupo foi significativo na duração do ciclo. Pode-se afirmar que, em 99,8% dos ciclos, a variação foi determinada pela incubação.

  14. Aqueous neem extract versus neem powder on Culex quinquefasciatus: implications for control in anthropogenic habitats.

    Science.gov (United States)

    Kudom, Andreas A; Mensah, Ben A; Botchey, Mary A

    2011-01-01

    Control programs using conventional insecticides to target anthropogenic mosquito habitats are very expensive because these habitats are widespread, particularly in cities of most African countries. Additionally, there are serious environmental concerns regarding large-scale application of most conventional insecticides. Clearly there is a need for alternative methods that are more effective, less expensive, and environmentally friendly. One such method would be the application of preparations made from parts of the neem tree, Azadirachta indica A. Jussieu (Sapindales: Meliaceae). In this study, aqueous crude extracts and crude powder were prepared from different parts of neem, and the efficacies of the preparations on juvenile stages of Culex quinquefasciatus Say (Diptera: Culicidae) were evaluated in the laboratory. When larvae were exposed to a concentration of 0.1 g/mL extract for 24 hours, percent mean mortality (± SE) was 72.7 plusmn; 1.8 for the bark, 68.7 ± 1.6 for fruits and 60 ± 1.6 for leaves. These means were not significantly different (χ(2) = 4.12; df = 2; p = 0.127). At a concentration of 0.01 g/mL, > 95% of the larvae died within 24 hours of exposure to powdered neem leaf, but it took 120 hours to reach the same level of larval mortality in aqueous leaf extract. The crude extract slowly inhibited the growth and development of mosquitoes while the crude powder acted more as a barrier; the mosquitoes probably died from suffocation. However, both types of preparations can be made and used by local people to control mosquito breeding in anthropogenic habitats, especially in urbanized areas.

  15. Evaluation of the pyrrole insecticide chlorfenapyr for the control of Culex quinquefasciatus Say.

    Science.gov (United States)

    Raghavendra, K; Barik, T K; Bhatt, R M; Srivastava, H C; Sreehari, U; Dash, A P

    2011-04-01

    Culex quinquefasciatus Say (Diptera: Culicidae) is a widely distributed mosquito vector species in India and also in other tropical regions of the world. This species is implicated in the transmission of lymphatic filariasis in many countries. This species is reported to be widely resistant to insecticides of different classes in current use. In the present study, bio-efficacy of chlorfenapyr, an insecticide of pyrrole class with a novel mode of action was tested for the control of Cx. quinquefasciatus. Studies were performed to determine the diagnostic dosage; residual efficacy on different artificially fabricated substrates, namely wood, mud, mud+lime, cement and cement+distemper; to assess cross-resistance with different insecticides; and synergism/antagonism using piperonyl butoxide (PBO). A dosage of 5.0% chlorfenapyr was determined as diagnostic dosage with 2 h exposure and 48 h holding period for assessing the susceptibility of mosquitoes. The residual efficacy was observed up to 34 weeks on wood and mud+lime substrates while on other substrates, it was about 15 weeks at a dosage of 400mg a.i./m(2). Laboratory-reared strains of Cx. quinquefasciatus showed cross-resistance, whereas field-collected mosquitoes showed absence of cross-resistance to chlorfenapyr. Potentiation bioassays showed antagonistic effect of PBO to chlorfenapyr toxicity owing to the involvement of oxidases in the initial step of a conversion of pro-insecticide chlorfenapyr to toxic form CL 303268. The present study results have shown that chlorfenapyr can be a potential insecticide for the control of multiple insecticide resistant strains of Cx. quinquefasciatus. However, in countries where indoor residual spray (IRS) is not targeted for the control of this species, like in India, chlorfenapyr used in IRS for the control of malaria vectors in rural and peri-urban areas can additionally provide control of Cx. quinquefasciatus also. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Culex nigripalpus Theobald (Diptera, Culicidae feeding habit at the Parque Ecológico do Tietê, São Paulo, Brazil Hábito alimentar de Culex nigripalpus Theobald (Diptera, Culicidae no Parque Ecológico do Tietê, São Paulo, Brasil

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    Gabriel Z. Laporta

    2008-01-01

    Full Text Available The blood feeding of a population of Cx. nigripalpus from Parque Ecológico do Tietê (PET was investigated using an indirect ELISA protocol. Mosquitoes were captured outside houses. Five hundred sixteen engorged females collected in a reforested area and 25 in an open area were tested. Rodents and dogs were the most common blood sources, accounting for approximately 65.3% of blood meals. Human blood was detected in 10.9%, dog blood in 26.1%, chicken blood in 2.4%, and rodent blood in 39.2% of the 541 insects tested. ELISA failed in identifying the blood sources of 233 engorged females, indicating that the mosquitoes may have fed on a host which was not tested. One hundred six individuals were positive for more than one host. The unweighted human blood index was 0.14 and the rodent/human, human/chicken, and dog/rodent feeding index values were 2.70, 1.51, and 1.33, respectively. Furthermore, rodents are defensive hosts for this haematophagous insect which looks for another host to complete blood-feeding. Considering that rodents are potential reservoirs for Mucambo virus and Saint Louis encephalitis virus and that Cx. nigripalpus feed on the blood of those mammals, we hypothesize that mosquito population in PET could participate in the transmission cycle of those arboviruses. Additionally, this species might be involved in the transmission of Dirofilaria immitis to dogs at this area.O hábito alimentar da população de Cx. nigripalpus do Parque Ecológico do Tietê (PET foi investigado usando um protocolo de ELISA indireto. Foram testadas 516 e 25 fêmeas ingurgitadas e capturadas, respectivamente, em áreas reflorestadas e abertas. Roedores e canídeos foram fontes alimentares mais freqüentes, em aproximadamente 65.3% dos repastos sangüíneos. De um total de 541 fêmeas ingurgitadas, foram detectadas freqüências de repastos sangüíneos em humanos (10.9%, canídeos (26.1%, galinídeos (2.4% e roedores (39.2%. As fontes alimentares de 233 fêmeas ingurgitadas (43.1% não foram identificadas, indicando que essas fêmeas se alimentaram possivelmente de outros hospedeiros não testados. Ainda, houve 106 indivíduos (34.4% que fizeram múltiplos repastos sangüíneos. O valor do índice de repastos sangüíneos em humanos foi 0.14 e as razões alimentares foram roedor/humano = 2.70, humano/galinídeo = 1.51 e canídeo/roedor = 1.33. Os roedores são hospedeiros defensivos para esse inseto hematófago o qual não persiste nestes hospedeiros e procura outro para completar o repasto sangüíneo. Considerando que os roedores são reservatórios potenciais de arbovírus Mucambo e São Luís e que Cx. nigripalpus realiza repastos sanguíneos nesses mamíferos, propõe-se a hipótese de que a população deste moquito poderia participar do ciclo de transmissão desses arbovírus no PET. Adicionalmente, esta espécie poderá se envolver na transmissão de Dirofilaria immitis para canídeos neste parque.

  17. Influence of resource levels, organic compounds and laboratory colonization on interspecific competition between the Asian tiger mosquito Aedes albopictus (Stegomyia albopicta) and the southern house mosquito Culex quinquefasciatus.

    Science.gov (United States)

    Allgood, D W; Yee, D A

    2014-09-01

    The mosquitoes Aedes albopictus (Stegomyia albopicta) (Skuse) and Culex quinquefasciatus (Say) (Diptera: Culicidae) are common inhabitants of tyres and other artificial containers, which constitute important peridomestic mosquito breeding habitats. We tested the hypotheses that interspecific resource competition between the larvae of these species is asymmetrical, that the concentration of chemicals associated with decomposing detritus affects the competitive outcomes of these species, and that wild and colonized strains of Cx. quinquefasciatus are affected differently by competition with Ae. albopictus. We conducted two laboratory competition experiments wherein we measured survivorship and estimated population growth (λ') in both species under multiple mixed-species densities. Under varying resource levels, competition was asymmetrical: Ae. albopictus caused competitive reductions or exclusions of Cx. quinquefasciatus under conditions of limited resources. In a second experiment, which used both wild and colonized strains of Cx. quinquefasciatus, organic chemical compounds associated with decomposing detritus did not affect the competitive outcome. The colonized strain of Cx. quinquefasciatus had greater survivorship and adult mass, and faster development times than the wild strain, but both strains were similarly affected by competition with Ae. albopictus. Competition between these species may have important consequences for vector population dynamics, especially in areas in which tyres and artificial containers constitute the majority of mosquito breeding habitats. © 2014 The Royal Entomological Society.

  18. Maintenance and Transmission of Keystone Virus by Aedes atlanticus (Diptera: Culicidae) and the Gray Squirrel in the Pocomoke Cypress Swamp, Maryland

    Science.gov (United States)

    1988-11-01

    transmission in atlanticus in the maintenance and transmission of the maintenance cycle of KEY virus (Fine & LeDuc this California serogroup virus at the PCS...adensis (Theobold), Culex salinarius Coquillett, vented the development of a viremia. Although and Psorophora ferox (von Humboldt) (Saugstad the viremic...evidence of KEY viral infection in al. 1975c) and for California encephalitis virus in the gray squirrel population was observed from Ae. melanimon (Dyar

  19. Difference in mosquito species (Diptera: Culicidae) and the transmission of Ross River virus between coastline and inland areas in Brisbane, Australia.

    Science.gov (United States)

    Hu, W; Mengersen, K; Dale, P; Tong, S

    2010-02-01

    This study examined the distribution of major mosquito species and their roles in the transmission of Ross River virus (RRV) infection for coastline and inland areas in Brisbane, Australia (27 degrees 28' S, 153 degrees 2' E). We obtained data on the monthly counts of RRV cases in Brisbane between November 1998 and December 2001 by statistical local areas from the Queensland Department of Health and the monthly mosquito abundance from the Brisbane City Council. Correlation analysis was used to assess the pairwise relationships between mosquito density and the incidence of RRV disease. This study showed that the mosquito abundance of Aedes vigilax (Skuse), Culex annulirostris (Skuse), and Aedes vittiger (Skuse) were significantly associated with the monthly incidence of RRV in the coastline area, whereas Aedes vigilax, Culex annulirostris, and Aedes notoscriptus (Skuse) were significantly associated with the monthly incidence of RRV in the inland area. The results of the classification and regression tree (CART) analysis show that both occurrence and incidence of RRV were influenced by interactions between species in both coastal and inland regions. We found that there was an 89% chance for an occurrence of RRV if the abundance of Ae. vigilax was between 64 and 90 in the coastline region. There was an 80% chance for an occurrence of RRV if the density of Cx. annulirostris was between 53 and 74 in the inland area. The results of this study may have applications as a decision support tool in planning disease control of RRV and other mosquito-borne diseases.

  20. Flight height preference for oviposition of mosquito (Diptera: Culicidae) vectors of sylvatic yellow fever virus near the hydroelectric reservoir of Simplício, Minas Gerais, Brazil.

    Science.gov (United States)

    Alencar, Jeronimo; Morone, Fernanda; De Mello, Cecília Ferreira; Dégallier, Nicolas; Lucio, Paulo Sérgio; de Serra-Freire, Nicolau Maués; Guimarães, Anthony Erico

    2013-07-01

    In this study, the oviposition behavior of mosquito species exhibiting acrodendrophilic habits was investigated. The study was conducted near the Simplicio Hydroelectic Reservoir (SHR) located on the border of the states of Minas Gerais and Rio de Janeiro, Brazil. Samples were collected using oviposition traps installed in forest vegetation cover between 1.70 and 4.30 m above ground level during the months of April, June, August, October, and December of 2011. Haemagogus janthinomys (Dyar), Haemagogus leucocelaenus (Dyar and Shannon), Aedes albopictus (Skuse), and Aedes terrens (Walker) specimens were present among the collected samples, the first two of which being proven vectors of sylvatic yellow fever (SYF) in Brazil and the latter is a vector of dengue in mainland Asia. As the data set was zero-inflated, a specific Poisson-based model was used for the statistical analysis. When all four species were considered in the model, only heights used for egg laying and months of sampling were explaining the distribution. However, grouping the species under the genera Haemagogus Williston and Aedes Meigen showed a significant preference for higher traps of the former. Considering the local working population of SHR is very large, fluctuating, and potentially exposed to SYF, and that this virus occurs in almost all Brazilian states, monitoring of Culicidae in Brazil is essential for assessing the risk of transmission of this arbovirus.

  1. Evolution of Resistance in Culex quinquefasciatus (Say) Selected With a Recombinant Bacillus thuringiensis Strain-Producing Cyt1Aa and Cry11Ba, and the Binary Toxin, Bin, From Lysinibacillus sphaericus.

    Science.gov (United States)

    Wirth, Margaret C; Walton, William E; Federici, Brian A

    2015-09-01

    Fourth instars of Culex quinquefasciatus (Say) (Diptera: Culicidae) were selected with a recombinant bacterial strain synthesizing the mosquitocidal proteins from Lysinibacillus sphaericus (Bin) and Cry11Ba and Cyt1Aa from Bacillus thuringiensis. Selection was initiated in Generation 1 with a concentration of 0.04 μg/ml, which rose to a maximum selection concentration of 8.0 μg/ml in Generation 14, followed by an unexpected, rapid increase in mortality in Generation 15. Subsequently, a selection concentration of 0.8 μg/ml was determined to be survivable. During this same period, resistance rose to nearly 1,000-fold (by Generation 12) and declined to 18.8-fold in Generation 19. Resistance remained low and fluctuated between 5.3 and 7.3 up to Generation 66. The cross-resistance patterns and interactions among the component proteins were analyzed to identify possible causes of this unusual pattern of evolution. Poor activity in the mid-range concentrations and lower-than-expected synergistic interactions were identified as potential sources of the early resistance. These findings should be considered in the development of genetically engineered strains intended to control nuisance and vector mosquitoes. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Mosquitoes (Diptera: Culicidae) Collected From Residential Yards and Dog Kennels in Florida Using Two Aspirators, a Sweep Net, or a CDC Trap.

    Science.gov (United States)

    Holderman, C J; Gezan, S A; Stone, A E S; Connelly, C R; Kaufman, P E

    2018-01-10

    Mosquito surveillance typically uses Centers for Disease Control and Prevention (CDC) mosquito light traps baited with CO2. From January 2013 to March 2015, we sampled seven field sites using three active mosquito-trapping techniques (two different aspirators and a sweep net) and the stationary CO2-baited CDC mosquito light trap to determine mosquito capture efficacy for each technique. Sampling occurred in four suburban backyards and three dog kennel facilities near Gainesville, FL, USA; species collection and relative abundance were measured. A total of 32 species and 70,090 individual mosquitoes were collected, including a new record for Alachua County, Florida, Aedes hendersoni (Cockerell). The dominant (>5% of total capture) mosquito species collected during the study included Aedes atlanticus (Dyar and Knab), Aedes infirmatus (Dyar and Knab), Anopheles crucians Wiedemann, Culiseta melanura (Coquillett), Culex erraticus (Dyar and Knab), Culex nigripalpus Theobald, and Uranotaenia sapphirina (Osten Sacken). The CDC trap captured the most species (29), followed by large aspirator (28), small aspirator (26), and the sweep net (23). All dominant species were captured with each sampling technique. Excluding Wyeomyia mitchellii (Theobald), all subdominant species (1-5% of total capture) were collected with each sampling technique. Future sampling should consider the utility (e.g., large numbers are readily collected) and limitations (e.g., personnel requirements) of aspirator collections when designing field-based mosquito sampling projects, especially those in residential areas or those focused upon species captured. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Biological control of container-breeding mosquitoes, Aedes albopictus and Culex quinquefasciatus, in a Japanese island by release of Toxorhynchites splendens adults.

    Science.gov (United States)

    Miyagi, I; Toma, T; Mogi, M

    1992-07-01

    To control container-breeding mosquitoes in the small island of Minnajima (0.56 km2), northern Okinawa, Japan, laboratory-reared adults (aged 7-10 days) of Toxorhynchites splendens (Palawan strain), a mosquito with predatory larvae, were released repeatedly during 1984, 1986 and 1987. Thirteen species of mosquitoes (Diptera: Culicidae) occurred in artificial containers, ground pools or crab-holes on the island, the predominant species being Aedes (Stegomyia) albopictus and Culex (Culex) quinquefasciatus. Predatory mosquito larvae of Culex (Lutzia) fuscanus and Cx (Lt.) halifaxii were found commonly in wet containers. In the first year of study, during a period of 54 days from 13 May to 5 July 1984, totals of 879 female and 806 male adults of Tx.splendens were released on six occasions. Similarly, between 29 April and 30 August 1986, totals of 2920 female and 2878 male adult Tx.splendens were released. In the third study year, totals of 2041 female and 1783 male Tx.splendens were released on eight occasions during 199 days from 23 April to 7 November 1987. After adult releases at two sites, the immature stages of Tx.splendens were found in 164 out of 502 traps in 1984, 421 out of 933 traps in 1986, and 151 out of 502 traps in 1987. The number of immatures of Tx.splendens present in each trap varied from 1 to 40 in 1984, 1 to 29 in 1986 and 1 to 9 in 1987. Numbers of immatures of the target species found in the traps during August-September averaged 71.9/trap/month in 1984, 114.7/trap/month in 1986 and 36.0/trap/month in 1987, significantly less in the traps with Tx.splendens than in those without them. The present field studies indicated that, in this small island, approximately 250 adult female and 200 male Tx.splendens per month should be released from April to November, and the releases should be carried out every year, in order to control effectively the target mosquitoes Ae.albopictus and Cx quinquefasciatus breeding in artificial containers in Minnajima.

  4. Ecologia de mosquitos (Diptera: Culicidae em criadouros naturais e artificiais de área rural do Norte do Estado do Paraná, Brasil. V. Coleta de larvas em recipientes artificiais instalados em mata ciliar Mosquito (Diptera: Culicidae ecology of natural and artificial rural breeding places in horthern Parana, Brazil. V. Larvae captured in artificial reservoirs installed in ciliary forest

    Directory of Open Access Journals (Sweden)

    José Lopes

    1997-08-01

    Full Text Available INTRODUÇÃO: A utilização pelos Culicidae de recipientes contendo água para a colocação de seus ovos, em área antropogênica, pode indicar plasticidade genética que os direcione evolutivamente no sentido da domiciliação. Nesse sentido, foram coletadas as diferentes espécies de Culicidae que colonizam recipientes alocados em mata ciliar, na área rural. MATERIAL E MÉTODO: Foram instalados recipientes de pneu, plástico, lata e bambu, em mata ciliar, em área rural no Norte do Paraná, Brasil. RESULTADOS: Coletaram-se larvas de Cx. grupo coronator, Cx. declarator, Cx. laticlasper, Cx. (Melanoconion secção Spissipes, Cx. tatoi, Tr. compressum, Tr. pallidiventer, Ae. terrens, Cx. mollis, Cx. bigoti, Hg. leucocelaenus, Cx. eduardoi, Cx. quinquefasciatus, Li. durhamii e Toxorhynchites sp. As cinco primeiras espécies foram específicas de pneus. As duas espécies de Trichoprosopon ficaram restritas a bambu. Ae. terrens e Cx. mollis foram caletadas em pneu e bambu, Cx. bigoti foi coletada em pneu, lata e bambu, enquanto que Hg. leucocelaenus só não foi encontrada em lata. As quatro últimas espécies foram coletadas em todos os tipos de recipientes. Cx. quinquefasciatus, Cx. eduardoi, Li. durhamii tiveram significante flutuação populacional. CONCLUSÕES: O pneu caracterizou-se como o recipiente mais aceito pelos culicídeos. As áreas onde a mata ciliar esteve mais densa e o locais onde o solo esteve mais úmido foram os pontos com maior número de capturas. A mata ciliar, mesmo muito reduzida e alterada, foi suficiente para abrigar várias espécies de culicídeos. As espécies caputradas podem ser portadoras de plasticidade gênica que as capacitem a colonizar ambientes antropogênicos.INTRODUCTION: The use of receptacles containing water for the laying of the Culicidae eggs in an anthropogenic area, may indicate a genetic plasticity thet leads them evolutionarily towards domiciliation. Thus, the varions species of Culicidae which

  5. Mortalidad en larvas de Culex quinquefasciatus y Anopheles albimanus (díptera: culicidae, causada con un producto de Bacillus sphaericus (bacteria: bacillaceae en presentación granulada en condiciones experimentales

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    Estrella Cárdenas Castro

    2012-06-01

    Full Text Available El objetivo de este estudio fue ensayar una serie de concentraciones de un producto granulado preparado con Bacillus sphaericus, sobre larvas de Culex quinquefasciatus y Anopheles albimanus en condiciones de laboratorio. Se utilizaron once concentraciones (20, 40, 60, 80, 100, 120, 140, 160, 180, 200 y 500 ppm sobre larvas de An. albimanus, y ocho concentraciones diez veces menores (2, 4, 6, 8, 10, 12, 14 y 16 ppm sobre larvas de Cx. quinquefasciatus. Se utilizaron 60 larvas y un control con 20 larvas por concentración. El tiempo de exposición fue de 48 h, a una temperatura de 28 ± 2 ºC. Para estimar las concentraciones letales 50 y 95 se utilizó la prueba Probit. Se encontró una CL95 de B. sphaericus entre 6,45 y 7,28 ppm para larvas de Cx. quinquefasciatus; mientras que en larvas de An. albimanus se observó una CL95 entre 450,56 y 466,76 ppm.

  6. Sex-specific gene expression in the mosquito Culex pipiens f. molestus in response to artificial light at night.

    Science.gov (United States)

    Honnen, Ann-Christin; Johnston, Paul R; Monaghan, Michael T

    2016-01-05

    Artificial light at night (ALAN) is a typical feature of urban areas and most organisms living in urban or suburban habitats are exposed to low levels of ALAN. Light is one of the most important environmental cues that organisms use to regulate their activities. Studies have begun to quantify the influence of ALAN on the behavior and ecology of organisms, but research on the effects at the molecular level remains limited. Mosquitoes in the Culex pipiens complex (Diptera, Culicidae) are widespread and abundant in urban areas where they are potential disease vectors. It is thus of particular interest to understand how ALAN may influence biologically and ecologically relevant traits. We used RNAseq to evaluate the transcriptome response in a Cx. pipiens f. molestus laboratory population that was exposed to near-natural light conditions (light:dark L16:D8 hours, "control") and ALAN conditions with 3 h of constant low-level light at night (L16 + Llow3:D5 hours, "low-light"). The resulting transcripts were mapped to the reference genome of the closely related Culex quinquefasciatus. Female expression patterns differed significantly between control and treatment conditions at five genes although none showed an absolute fold change greater than two (FC > 2). In contrast, male expression differed at 230 genes (74 with FC > 2). Of these, 216 genes (72 with FC > 2) showed reduced expression in the low-light treatment, most of which were related to gametogenesis, lipid metabolism, and immunity. Of the 14 genes (two with FC > 2) with increased expression, only five had any functional annotation. There was a pronounced sex-bias in gene expression regardless of treatment, with 11,660 genes (51 % of annotated genes; 8694 with FC > 2; 48 % of annotated genes) differentially expressed between males and females, including 14 genes of the circadian clock. Our data suggest a stronger response to artificial light by males of Cx. pipiens f. molestus than by

  7. Entomological surveillance, spatial distribution, and diversity of Culicidae (Diptera) immatures in a rural area of the Atlantic Forest biome, State of São Paulo, Brazil.

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    Piovezan, Rafael; Rosa, Stéfany Larissa; Rocha, Matheus Luca; de Azevedo, Thiago Salomão; Von Zuben, Cláudio José

    2013-12-01

    Because of the high adaptive capacity of mosquitoes, studies that focus on transitional environments become very important, such as those in rural areas, which are considered as bridges between wild diseases and human populations of urban areas. In this study, a survey of the existing species of mosquitoes was performed in an Atlantic Forest area of the city of Santa Bárbara d'Oeste, São Paulo state, Brazil, using traps for immatures and analyzing the frequency and distribution of these insects over the sampling months. Five mosquito species were found: Aedes albopictus (the most frequent species), Aedes aegypti, Aedes fluviatilis, Culex quinquefasciatus, and Toxorhynchites theobaldi. The 4,524 eggs collected in ovitraps showed the presence of the tribe Aedini. Aedes aegypti and Ae. albopictus were identified after larval hatching in the laboratory, with different spatial distributions: the first of which coincides with the area of greatest diversity calculated using the Simpson index, while the second does not. The association of ecological analysis of spatial diversity with simple methods of data collection enables the identification of possible epidemiological risk situations and is a strategy that may be implemented to monitor ecological processes resulting from the interaction among different species of mosquitoes. © 2013 The Society for Vector Ecology.

  8. Effect of food on immature development, consumption rate, and relative growth rate of Toxorhynchites splendens (Diptera: Culicidae, a predator of container breeding mosquitoes

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    D Dominic Amalraj

    2005-12-01

    Full Text Available Food utilization by the larvae of Toxorhynchites splendens (Wiedemann was studied in the laboratory by offering larvae of Aedes aegypti Linnaeus, Anopheles stephensi (Liston, and Culex quinquefasciatus (Say. Quantitative analyses of data indicated that immature development was significantly faster with increase in food availability. The regression analysis showed that the degrees of the relationship between immature duration (Id and food availability were higher when offered early instars of prey (first and second instars than late instars. Consumption rate (Cr of the predator increased with increase in food availability and this relationship was highly significant when larvae of An. stephensi were offered as food. Consumption rate to food level decreased with increase in the age class of the prey. There was a significant negative correlation between Id and Cr. This aspect helps to increase population turnover of T. splendens in a shorter period when the prey is abundant. Conversely, the predator compensated the loss in daily food intake at low food level by extending Id thereby attains the minimum threshold pupal weight for adult emergence. There was an increase in the relative growth rate (RGR of the predator when An. stephensi was offered as prey and this was related to the high protein content of the prey per body weight. There was a positive correlation between Cr and RGR. This adaptive life characteristic strategy of this predator is useful for mass-rearing for large scale field release programmes in the control of container breeding mosquitoes is discussed.

  9. Effect of food on immature development, consumption rate, and relative growth rate of Toxorhynchites splendens (Diptera: Culicidae), a predator of container breeding mosquitoes.

    Science.gov (United States)

    Dominic Amalraj, D; Sivagnaname, N; Das, P K

    2005-12-01

    Food utilization by the larvae of Toxorhynchites splendens (Wiedemann) was studied in the laboratory by offering larvae of Aedes aegypti Linnaeus, Anopheles stephensi (Liston), and Culex quinquefasciatus (Say). Quantitative analyses of data indicated that immature development was significantly faster with increase in food availability. The regression analysis showed that the degrees of the relationship between immature duration (Id) and food availability were higher when offered early instars of prey (first and second instars) than late instars. Consumption rate (Cr) of the predator increased with increase in food availability and this relationship was highly significant when larvae of An. stephensi were offered as food. Consumption rate to food level decreased with increase in the age class of the prey. There was a significant negative correlation between Id and Cr. This aspect helps to increase population turnover of T. splendens in a shorter period when the prey is abundant. Conversely, the predator compensated the loss in daily food intake at low food level by extending Id thereby attains the minimum threshold pupal weight for adult emergence. There was an increase in the relative growth rate (RGR) of the predator when An. stephensi was offered as prey and this was related to the high protein content of the prey per body weight. There was a positive correlation between Cr and RGR. This adaptive life characteristic strategy of this predator is useful for mass-rearing for large scale field release programmes in the control of container breeding mosquitoes is discussed.

  10. [Comparison of taxonomic importance of morphological and molecular-genetic characters in systematics of Microsporidia (Microsporidia) of blood-sucking mosquitoes (Diptera: Culicidae)].

    Science.gov (United States)

    Simakova, A V

    2014-01-01

    Comparative analysis of the taxonomic position of microsporidians from mosquitoes of the family Culicidae, for which SSU rDNA sequences data were obtained, demonstrates partial contradiction of systems based on morphological and phylogenetic characteristics. Representatives of the genera Anncaliia Issi. et al., 1993 and Vavraia Weiser, 1977 constitute separate evolutionary branches of the phylogenetic tree of microsporidians of blood-sucking mosquitoes. Representatives of other genera, for which the SSU rRNA sequences data were obtained (Amblyospora Hazard, Oldacre, 1975, Andreanna Simakova et al., 2008, Culicospora (Kudo, 1921), Weiser, 1977, Culicosporella Hazard, Savage, 1970, Edhazardia (Kudo, 1930), Sprague, Fucuda, 1989, Hazardia Weiser, 1977, Hyalinocysta Hazard, Oldacre, 1975, Novothelohania Andreadis et al., 2012, Parathelohania Codreanu, 1966, Senoma Simakova et al., 2005, and Trichoctosporea Larsson, 1994), form a separate, monophyletic group in the tree of Microsporidia. They are closely related and probably possess a common ancestor. The genera Amblyospora, Culicospora, Edhazardia, and Trichoctosporea were placed in the family Amblyosporidae with the revision of the diagnosis. On the basis of the obtained data on morphology and molecular phylogeny we placed Intrapredatorus barri Chen et al:, 1998 into the genus Amblyospora as Amblyospora barri, comb. nov., and also the species Amblyospora bakcharia Andreadis et al., 2012, A. kazankia Andreadis et al., 2012, A. mocrushinia Andreadis et al., 2012, and A. rugosa Simakova, Pankova, 2005 into the genus Trichoctosporea as Trichoctosporea bakcharia comb. nov., T. kazankia comb. nov., T. mocrushinia comb. nov., and T. rugosa comb. nov. Microsporidians of blood-sucking mosquitoes originally possessed complicated life cycles with transovarial and oral transmissions and with the presence of intermediate hosts (lower crustaceans). Later, some microsporidians had lost a part of their life cycle, either during

  11. Longitudinal evaluation of Ocimum and other plants effects on the feeding behavioral response of mosquitoes (Diptera: Culicidae in the field in Tanzania

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    Tenu Filemoni

    2008-10-01

    Full Text Available Abstract Background The use of repellent materials from plants against nuisance insects is common with great potential to compliment existing malaria control programmes and this requires evaluation in the field. Ocimum plant species, Ocimum suave (Willd and O. kilimandscharicum (Guerke materials and their essential oils extracted by steam distillation were evaluated in the field and experimental huts for repellence, exophily and feeding inhibition effects against three mosquito species, Anopheles arabiensis (Patton, An. gambiae ss (Giles and Culex quinquefasciatus (Say. The protective effect of essential oils from Ocimum plants were compared with N, N-diethly-3- methylbenzamide (DEET, a standard synthetic repellent. Also, the protective effect of fumigation by burning of repellent plants; Ocimum suave, Ocimum kilimandscharicum, Azadirachta indica, Eucalyptus globules and Lantana camara were tested in experimental huts and selected local houses. Results In the field, protection by Ocimum plants from mosquito bites was high and there was small variation among different mosquito species. Protection efficiency was 93.4%, 91.98% and 89.75% for An. arabiensis while for Cx. quinquefaciatus it was 91.30%, 88.65% and 90.50% for DEET, Ocimum suave and O. kilimandscharicum respectively. In the experimental hut, deterrence induced by burning of Ocimum and other plants ranged from 73.1.0% to 81.9% for An. arabiensis and 56.5% to 67.8% for Cx. quinquefaciatus, while feeding inhibition was 61.1% to 100% for An. arabiensis and 50% to 100% for Cx. quinquefaciatus. Evaluations under field conditions confirmed high protective efficacy, enhanced feeding inhibition and house entry inhibition (Deterrence. Conclusion This study shows the potential of Ocimum suave and Ocimum kilimandscharicum crude extracts and whole plants of Ocimum suave, Ocimum kilimandscharicum, Azadirachta indica, Eucalyptus globules and Lantana camara for use in protecting against human biting

  12. Isolations of Jamestown Canyon virus (Bunyaviridae: Orthobunyavirus) from field-collected mosquitoes (Diptera: Culicidae) in Connecticut, USA: a ten-year analysis, 1997-2006.

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    Andreadis, Theodore G; Anderson, John F; Armstrong, Philip M; Main, Andrew J

    2008-04-01

    Jamestown Canyon virus (JCV) (Bunyaviridae: Orthobunyavirus) is a mosquito-borne zoonosis belonging to the California serogroup. It has a wide geographic distribution, occurring throughout much of temperate North America. White-tailed deer, Odocoileus virginianus are the principal amplification hosts, and boreal Aedes and Ochlerotatus mosquitoes are the primary vectors. A 10-year study was undertaken to identify potential mosquito vectors in Connecticut, quantify seasonal prevalence rates of infection, and define the geographic distribution of JCV in the state as a function of land use and white-tailed deer populations, which have increased substantially over this period. Jamestown Canyon virus was isolated from 22 mosquito species. Five of them, Ochlerotatus canadensis, Oc. cantator, Anopheles punctipennis, Coquillettidia perturbans, and Oc. abserratus were incriminated as the most likely vectors, based on yearly isolation frequencies and the spatial geographic distribution of infected mosquitoes. Jamestown Canyon virus was isolated from Oc. canadensis more consistently and from a greater range of collection sites than any other species. Frequent virus isolations were also made from Aedes cinereus, Aedes vexans, and Oc. sticticus, and new North American isolation records were established for Anopheles walkeri, Culex restuans, Culiseta morsitans, Oc. sticticus, Oc. taeniorhynchus, and Psorophora ferox. Other species from which JCV was isolated included C. melanura, Oc. aurifer, Oc. communis, Oc. excrucians, Oc. provocans, Oc. sollicitans, Oc. stimulans, Oc. triseriatus, and Oc. trivittatus. Jamestown Canyon virus was widely distributed throughout Connecticut and found to consistently circulate in a diverse array of mosquito vectors. Infected mosquitoes were collected from June through September, and peak infection rates paralleled mosquito abundance from mid-June through mid-July. Infection rates in mosquitoes were consistent from year to year, and overall virus

  13. Diversity of Mosquitoes (Diptera: Culicidae) Attracted to Human Subjects in Rubber Plantations, Secondary Forests, and Villages in Luang Prabang Province, Northern Lao PDR.

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    Tangena, Julie-Anne A; Thammavong, Phoutmany; Malaithong, Naritsara; Inthavong, Thavone; Ouanesamon, Phuthasone; Brey, Paul T; Lindsay, Steve W

    2017-11-07

    The impact of the rapid expansion of rubber plantations in South-East Asia on mosquito populations is uncertain. We compared the abundance and diversity of adult mosquitoes using human-baited traps in four typical rural habitats in northern Lao PDR: secondary forests, immature rubber plantations, mature rubber plantations, and villages. Generalized estimating equations were used to explore differences in mosquito abundance between habitats, and Simpson's diversity index was used to measure species diversity. Over nine months, 24,927 female mosquitoes were collected, including 51 species newly recorded in Lao PDR. A list of the 114 mosquito species identified is included. More mosquitoes, including vector species, were collected in the secondary forest than immature rubber plantations (rainy season, odds ratio [OR] 0.33, 95% confidence interval [CI] 0.31-0.36; dry season, 0.46, 95% CI 0.41-0.51), mature rubber plantations (rainy season, OR 0.25, 95% CI 0.23-0.27; dry season, OR 0.25, 95% CI 0.22-0.28), and villages (rainy season, OR 0.13, 95% CI 0.12-0.14; dry season, 0.20, 95% CI 0.18-0.23). All habitats showed high species diversity (Simpson's indexes between 0.82-0.86) with vectors of dengue, Japanese encephalitis (JE), lymphatic filariasis, and malaria. In the secondary forests and rubber plantations, Aedes albopictus (Skuse), a dengue vector, was the dominant mosquito species, while in the villages, Culex vishnui (Theobald), a JE vector, was most common. This study has increased the overall knowledge of mosquito fauna in Lao PDR. The high abundance of Ae. albopictus in natural and man-made forests warrants concern, with vector control measures currently only implemented in cities and villages. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. The abundance and host-seeking behavior of culicine species (Diptera: Culicidae and Anopheles sinensis in Yongcheng city, people's Republic of China

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    Liu Xiao-Bo

    2011-11-01

    Full Text Available Abstract Background The knowledge of mosquito species diversity and the level of anthropophily exhibited by each species in a region are of great importance to the integrated vector control. Culicine species are the primary vectors of Japanese encephalitis (JE virus and filariasis in China. Anopheles sinensis plays a major role in the maintenance of Plasmodium vivax malaria transmission in China. The goal of this study was to compare the abundance and host-seeking behavior of culicine species and An. sinensis in Yongcheng city, a representative region of P. vivax malaria. Specifically, we wished to determine the relative attractiveness of different animal baits versus human bait to culicine species and An. sinensis. Results Culex tritaeniorhynchus was the most prevalent mosquito species and An. sinensis was the sole potential vector of P. vivax malaria in Yongcheng city. There were significant differences (P An. sinensis and Cx. tritaeniorhynchus collected in distinct baited traps. The relative attractiveness of animal versus human bait was similar towards both An. sinensis and Cx. tritaeniorhynchus. The ranking derived from the mean number of mosquitoes per bait indicated that pigs, goats and calves frequently attracted more mosquitoes than the other hosts tested (dogs, humans, and chickens. These trends were similar across all capture nights at three distinct villages. The human blood index (HBI of female An. sinensis was 2.94% when computed with mixed meals while 3.70% computed with only the single meal. 19:00~21:00 was the primary peak of host-seeking female An. sinensis while 4:00~5:00 was the smaller peak at night. There was significant correlation between the density of female An. sinensis and the average relative humidity (P Conclusions Pigs, goats and calves were more attractive to An. sinensis and Cx. tritaeniorhynchus than dogs, humans, and chickens. Female An. sinensis host-seeking activity mainly occurred from 19:00 to 21:00. Thus

  15. Spatial-Temporal Analysis of Cache Valley Virus (Bunyaviridae: Orthobunyavirus) Infection in Anopheline and Culicine Mosquitoes (Diptera: Culicidae) in the Northeastern United States, 1997–2012

    Science.gov (United States)

    Armstrong, Philip M.; Anderson, John F.; Main, Andrew J.

    2014-01-01

    Abstract Cache Valley virus (CVV) is a mosquito-borne bunyavirus (family Bunyaviridae, genus Orthobunyavirus) that is enzootic throughout much of North and Central America. White-tailed deer (Odocoileus virginianus) have been incriminated as important reservoir and amplification hosts. CVV has been found in a diverse array of mosquito species, but the principal vectors are unknown. A 16-year study was undertaken to identify the primary mosquito vectors in Connecticut, quantify seasonal prevalence rates of infection, and define the spatial geographic distribution of CVV in the state as a function of land use and white-tailed deer populations, which have increased substantially over this period. CVV was isolated from 16 mosquito species in seven genera, almost all of which were multivoltine and mammalophilic. Anopheles (An.) punctipennis was incriminated as the most consistent and likely vector in this region on the basis of yearly isolation frequencies and the spatial geographic distribution of infected mosquitoes. Other species exhibiting frequent temporal and moderate spatial geographic patterns of virus isolation within the state included Ochlerotatus (Oc.) trivittatus, Oc. canadensis, Aedes (Ae.) vexans, and Ae. cinereus. New isolation records for CVV were established for An. walkeri, Culiseta melanura, and Oc. cantator. Other species from which CVV was isolated included An. quadrimaculatus, Coquillettidia perturbans, Culex salinarius, Oc. japonicus, Oc. sollicitans, Oc. taeniorhynchus, Oc. triseriatus, and Psorophora ferox. Mosquitoes infected with CVV were equally distributed throughout urban, suburban, and rural locales, and infection rates were not directly associated with the localized abundance of white-tailed deer, possibly due to their saturation throughout the region. Virus activity in mosquitoes was episodic with no consistent pattern from year-to-year, and fluctuations in yearly seasonal infection rates did not appear to be directly impacted by

  16. Spatial-temporal analysis of Cache Valley virus (Bunyaviridae: Orthobunyavirus) infection in anopheline and culicine mosquitoes (Diptera: Culicidae) in the northeastern United States, 1997-2012.

    Science.gov (United States)

    Andreadis, Theodore G; Armstrong, Philip M; Anderson, John F; Main, Andrew J

    2014-10-01

    Cache Valley virus (CVV) is a mosquito-borne bunyavirus (family Bunyaviridae, genus Orthobunyavirus) that is enzootic throughout much of North and Central America. White-tailed deer (Odocoileus virginianus) have been incriminated as important reservoir and amplification hosts. CVV has been found in a diverse array of mosquito species, but the principal vectors are unknown. A 16-year study was undertaken to identify the primary mosquito vectors in Connecticut, quantify seasonal prevalence rates of infection, and define the spatial geographic distribution of CVV in the state as a function of land use and white-tailed deer populations, which have increased substantially over this period. CVV was isolated from 16 mosquito species in seven genera, almost all of which were multivoltine and mammalophilic. Anopheles (An.) punctipennis was incriminated as the most consistent and likely vector in this region on the basis of yearly isolation frequencies and the spatial geographic distribution of infected mosquitoes. Other species exhibiting frequent temporal and moderate spatial geographic patterns of virus isolation within the state included Ochlerotatus (Oc.) trivittatus, Oc. canadensis, Aedes (Ae.) vexans, and Ae. cinereus. New isolation records for CVV were established for An. walkeri, Culiseta melanura, and Oc. cantator. Other species from which CVV was isolated included An. quadrimaculatus, Coquillettidia perturbans, Culex salinarius, Oc. japonicus, Oc. sollicitans, Oc. taeniorhynchus, Oc. triseriatus, and Psorophora ferox. Mosquitoes infected with CVV were equally distributed throughout urban, suburban, and rural locales, and infection rates were not directly associated with the localized abundance of white-tailed deer, possibly due to their saturation throughout the region. Virus activity in mosquitoes was episodic with no consistent pattern from year-to-year, and fluctuations in yearly seasonal infection rates did not appear to be directly impacted by overall

  17. Acute larvicidal toxicity of five essential oils (Pinus nigra, Hyssopus officinalis, Satureja montana, Aloysia citrodora and Pelargonium graveolens) against the filariasis vector Culex quinquefasciatus: Synergistic and antagonistic effects.

    Science.gov (United States)

    Benelli, Giovanni; Pavela, Roman; Canale, Angelo; Cianfaglione, Kevin; Ciaschetti, Giampiero; Conti, Fabio; Nicoletti, Marcello; Senthil-Nathan, Sengottayan; Mehlhorn, Heinz; Maggi, Filippo

    2017-04-01

    Mosquito vector control is facing a number of important and timely challenges, mainly due to the rapid development of pesticide resistance and environmental concerns. In this scenario, screening of botanical resources for their mosquitocidal activity may offer effective and eco-friendly tools against Culicidae vectors. Culex quinquefasciatus Say (Diptera: Culicidae) is a vector of lymphatic filariasis and of dangerous arboviral diseases, such as West Nile and St. Louis encephalitis. In this study, the chemical composition of five essential oils obtained from different plants, namely Pinus nigra J.F. Arnold var. italica (Pinaceae), Hyssopus officinalis L. subsp. aristatus (Lamiaceae), Satureja montana L. subsp. montana (Lamiaceae), Aloysia citriodora Palau (Verbenaceae) and Pelargonium graveolens L'Hér (Geraniaceae), was investigated by GC-MS analysis. Furthermore, it was evaluated their acute toxicity on larvae of C. quinquefasciatus. Then, the most effective oils were selected, in order to focus on the potential synergistic and antagonistic effects, testing them in binary mixtures on C. quinquefasciatus larvae. Results showed that the higher effectiveness was obtained by S. montana subsp. montana essential oil (LC 50 =25.6μL·L -1 ), followed by P. nigra var. italica (LC 50 =49.8μL·L -1 ) and A. citriodora (LC 50 =65.6μL·L -1 ), while the other essential oils showed LC 50 values higher than 90μL·L -1 . The larvicidal effectiveness can be enhanced by preparing simple binary mixtures of essential oils, such as S. montana+A. citriodora (ratio 1:1), which showed higher larvicidal toxicity (LC 50 =18.3μL·L -1 ). On the other hand, testing S. montana+P. nigra (1:1) an antagonistic effect was detected, leading to a LC 50 (72.5μL·L -1 ) higher than the LC 50 values calculated for the two oils tested separately. Overall, our results add useful knowledge to allow the employ of synergistic essential oil blends as effective, cheap and eco-friendly mosquito

  18. Ecologia de mosquitos (Diptera, Culicidae em áreas do Parque Nacional do Iguaçu, Brasil: 1 ­ Distribuição por hábitat Mosquito (Diptera, Culicidae ecology in the Iguaçu National Park, Brazil: 1 ­ Habitat distribution

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    Anthony Érico Guimarães

    2003-08-01

    Full Text Available Estabelecemos a influência exercida pela cobertura vegetal de quatro diferentes biótopos em áreas do Parque Nacional do Iguaçu (PNI sobre a fauna local de mosquitos. Realizaram-se capturas bimestrais, em isca humana e armadilha Shannon, em três diferentes períodos do dia, em ambiente silvestre e domiciliar, durante 24 meses consecutivos. Dentre os 20.273 espécimes de fêmeas adultas capturadas, pertencentes a 44 espécies, Ochlerotatus serratus (10,3%, Haemagogus leucocelaenus (9,7%, Mansonia titillans (9,6% e Chagasia fajardoi (8,8% foram predominantes. Anopheles cruzii, Runchomyia theobaldi, Wyeomyia aporonoma e Wy. confusa ocorreram exclusivamente em áreas com vegetação bem preservada e densa configuração. Culex nigripalpus, Oc. pennai, Oc. serratus, Sabethes purpureus e Sa. albiprivus foram capturados nos três biótopos essencialmente silvestres. Na mata no entorno da represa foram capturadas principalmente An. albitarsis s.l., An. galvaoi, An. evansae, An. fluminensis, Coquillettidia venezuelensis, Cq. juxtamansonia, Wy. quasilongirostris e Onirion personatum. As espécies que apresentaram maiores incidências na área sob ação antrópica foram Ch. fajardoi, Cq. fasciolata, Cq. nitens e Ma. titillans.A study of the mosquito fauna in the Iguaçu National Park focused on population behavior in four biotopes with different types of plant cover inside the Park. Systematic bimonthly diurnal and nocturnal human bait and Shannon trap captures were conducted in both forest and domiciliary environments over the course of 24 months. A total of 20,273 adult mosquito specimens belonging to 44 species were collected: Ochlerotatus serratus (10.3%, Haemagogus leucocelaenus (9.7%, Mansonia titillans (9.6%, and Chagasia fajardoi (8.8% were the most frequently captured mosquitoes. Anopheles cruzii, Runchomyia theobaldi, Wyeomyia aporonoma, and Wy. confusa were captured almost exclusively in well-preserved areas with dense forest cover. Culex

  19. Culicídeos associados a entrenós de bambu e bromélias, com ênfase em Aedes (Stegomyia albopictus (Diptera, Culicidae na Mata Atlântica, Paraná, Brasil Culicids associated with bamboo internodes and bromeliads, with emphasis on Aedes (Stegomyia albopictus (Diptera, Culicidae in the Atlantic Forest, Paraná, Brazil

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    Allan Martins da Silva

    2004-03-01

    Full Text Available Aedes (Stegomyia albopictus (Skuse, 1894 larvae were recorded for the first time in the internodes of bamboo cuts found in the Atlantic Forest in the State of Paraná, Brazil. The bamboo, Bambusa sp., was introduced in the area of Imbucuí-Mirim town, across the municipal district of Paranaguá and towards the interior of the Atlantic Forest. A total of 251 larvae of Aedes albopictus (37.9%, Culex (Microculex spp. (13.9%, Limatus durhami Theobald, 1901 (39.8%, Toxorhynchites sp. (0.4% and Wyeomyia spp. (8.0% were collected from bamboo internodes filled with rain and from the terrestrial Bromeliaceae and epiphytas found near the bamboo bushes. Aedes albopictus was found in bamboo internodes containing 30 to 254 ml of rain, sometimes coexisting with Li. durhami. Borders of forest ecosystems should be characterized as risk areas for arbovirosis transmission, since they sustain the circulation of vertebrates and arthropodal hematophagus, not only in the wild but also in the anthropic areas.

  20. Medical Entomology Studies - VI. A Revision of the Subgenus Lophoceraomyia of the Genus Culex in the Oriental Region (Diptera: Culicidae) (Contributions of the American Entomological Institute, Volume 13, Number 4, 1977)

    Science.gov (United States)

    1977-01-01

    cephalothorax and metanotum. Trumpet. Brownish, short, stout, sausage -like, apex slightly projecting beyond margin of middorsal ridge in flat preparation...Subgenus LoPhoceraow2yia in the Oriental Region 137 lighter or yellowish white. Trumpet. Dark brown, short, stout, sausage -like. Complete chaetotaxy...Publ. 20: 1-147. Les moustiques de la Cochinchine et du Sud-Annam. Arch. Inst. Pasteur d’Indochine 3-4: 75-121. Les moustiques de la Cochinchine

  1. Medical Entomolgy Studies - VI. A Revision of the Subgenus Lophoceraomyia of the Genus Culex in the Oriental Region (Diptera: Culicidae) (Contributions of the American Entomological Institute. Volume 13, Number 4)

    Science.gov (United States)

    1977-01-01

    cephalothorax and metanotum. Trumpet. Brownish, short, stout, sausage -like, apex slightly projecting beyond margin of middorsal ridge in flat preparation...Subgenus LoPhoceraow2yia in the Oriental Region 137 lighter or yellowish white. Trumpet. Dark brown, short, stout, sausage -like. Complete chaetotaxy...Publ. 20: 1-147. Les moustiques de la Cochinchine et du Sud-Annam. Arch. Inst. Pasteur d’Indochine 3-4: 75-121. Les moustiques de la Cochinchine

  2. Medical Entomology Studies - XIII. The Myzomyia Series of Anopheles (Cellia) in Thailand, with Emphasis on Intra-Interspecific Variations (Diptera: Culicidae) (Contributions of the American Entomological Institute. Volume 17, Number 4, 1980)

    Science.gov (United States)

    1980-01-01

    Scanlon 1975) and several regional weather patterns (see below), Thailand has a wide variety of habitats with a tremendous variety of plant and... Biologia 18: 29-41. ASLAMKHAN, M. and R. H. BAKER 1969. Karyotypes of some Anopheles, Ficalbia and Culex mosquitoes of Asia. Pak. J. Zool. 1: 1-7

  3. Characterization of Aedes albopictus (Skuse, 1894 (Diptera:Culicidae larval habitats near the Amazon River in Colombia Caracterización preliminar de los sitios de cría de Aedes (Stegomyia albopictus (Skuse, 1894 (Diptera: Culicidae en el municipio de Leticia, Amazonas, Colombia

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    Víctor Alberto Olano

    2009-09-01

    Full Text Available Introduction. Because the role of Aedes albopictus as an incriminated vector of several viral pathogens, its control is important to human health. To establish appropriate control methods, characterization of the larval habitats is a necessary first step.
    Objective. Habitats of the immature stages of Ae. albopictus were characterized with respect to physical-chemical parameters and by floral and faunal arrays present.
    Materials and methods. Leticia is located at the southernmost tip of Colombia on the banks of the Amazon River. In the urban area, 154 houses were inspected in December 2002 and January 2003. Physical-chemical data were collected, including exposure to sunlight, location, container size and material, water conductivity, and dissolved oxygen. Macroinvertebrates and plankton samples were taken at each positive larval site. The results were compared using descriptive analysis, principal component analysis, classification dendrograms, and diversity indexes.
    Results. Twenty-one habitats were found positive for Diptera, and 13 were positive for Ae. albopictus larvae. Most of the positive habitats (92% were located near the houses--they were small or medium size receptacles located in the shade. This water generally had low conductivity and low turbidity, although high values of these parameters were also identified. The habitats had low diversity indexes for macroinvertebrates and high diversity indexes for plankton. In the principal component analysis, significant correlation was found with mites, oligochaetes and hemipterans (the macroinvertebrates and with bacilarophyceaes, clorophyceaes and cianophyceas (the algal forms.
    Conclusion. In Leticia, females of Ae. albopictus were found in newly established habitats with sufficient availability of resources, low conductivity, and turbidity, lower intra-and interspecific competition.Introducción. Dada la importancia de Aedes albopictus en la salud pública, es necesario

  4. Alguns aspectos da ecologia dos mosquitos (Diptera: Culicidae de uma área de planície (Granjas Calábria, em Jacarepaguá, Rio de Janeiro: III. Preferência horária das fêmeas para o hematofagismo Aspects of the ecology of mosquitoes (Diptera: Culicidae in a plane area (Granjas Calábria, in Jacarepaguá, Rio de Janeiro: III. Female preferencial period for biting

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    Ricardo Lourenço-de-Oliveira

    1985-06-01

    Full Text Available Apresentamos os resultados de observação sobre o ciclo circadiano de atividade hematofágica dos mosquitos, em Granja Calábria, Jacarepaguá, na planície litorânea do Rio de Janeiro, onde realizamos, em isca humana, ao ar livre, capturas semanais, de 8 às 10, de 13 às 15 e 18 às 20 horas, de agosto de 1981 a julho de 1982, além de três capturas horárias de 24 horas seguidas. A maioria das espécies locais revelou caráter crepuscular vespertino e noturno. Contudo Limatus durhami, Phoniomyia davisi, Wyeomyia leucostigma e Wyeomyia (Dendromyia sp. foram essencialmente diurnas, enquanto Anopheles albitarsis, Culex chidesteri e Culex quinquefasciatus foram obtidas somente no crepúsculo vespertino e à noite. Embora Anopheles aquasalis, Culex coronator, Culex saltanensis, Culex crybda e Coquillettidia venezuelensis fossem preponderantemente noturnas e Phoniomyia deanei e Phoniomyia theobaldi principalmente diurnas, obtivemô-las algumas vezes, fora do horário preferencial, sendo que Phoniomyia deanei teve nítido incremento pré-crepuscular vespertino. Aedes scapularis, Aedes taeniorhynchus e Mansonia titillans, espécies mais ecléticas, picaram durante todo o nictêmero, mas com flagrante acentuação crepuscular vespertina.This paper presents the results of obsrvation on the circadian biting cycle of mosquitoes, at Granjas Calábria, Jacarepaguá, in the coastal lowland of Rio de Janeiro, Brazil, where we carried out weekly outdoor captures on human bait, from 8 to 10 a.m. and from 1 to 3 and 6 to 8 p.m., from August 1981 to July 1982, as well as three nyctemeral captures also on human bait. Most of the local species were more frequent at sunset and at night. Li. durhami, Ph. davisi, Wy. leucostigma and Wyeomyia (Den. sp. were clearly diurnal, while An. albitarsis, Cx. chidesteri and Cx. quinquefasciatus were obtained only at sunset and at night. Although An. aquasalis, Cx. coronator, Cx. saltanensis, Cx. crybda and Cq. venezuelensis

  5. Effect of the combined application of microencapsulated synthetic oviposition pheromone (MSP) with different larvicidal agents on the oviposition of Culex pipiens biotype molestus.

    Science.gov (United States)

    Michaelakis, Antonios; Papachristos, Dimitrios P; Rumbos, Christos I; Athanassiou, Christos G

    2017-08-29

    Attract-and-kill strategies, in which a behavior-modifying stimulus (e.g. a pheromone) is integrated with a pest control agent, have lately attracted increased interest for mosquito control. Previously, it was demonstrated that the polyurea microencapsulated synthetic oviposition pheromone 6-acetoxy-5-hexadecanolide (MSP) was sufficiently attractive to gravid females of Culex pipiens L. biotype molestus Førskal (Diptera: Culicidae) for a period of 40 days. Furthermore, it was shown that MSP could be effectively combined with the organophosphate temephos to achieve efficient mosquito control. In the present study, the effect of the combined application of MSP with commonly used larvicides on the oviposition response of Cx. p. biotype molestus females over time was investigated in two-choice oviposition bioassays. As larvicides, the insect growth regulator diflubenzuron and the bacterial insecticide spinosad were evaluated at their lowest recommended label dose, whereas temephos was used as a control. When MSP was applied in combination with diflubenzuron, the attractancy of MSP to gravid females was in all cases negatively affected, as fewer egg rafts were laid in pots treated with MSP and diflubenzuron compared with MSP alone. Spinosad did not reduce, but rather increased, the attractive effect of the oviposition pheromone at the beginning of the bioassay (at 2 days of ageing) when co-applied; however, the observed attractive effect was significantly reduced after 7 days of ageing and remained stable at the same level until the termination of the bioassay. Finally, the oviposition pattern of egg rafts laid on the pot with MSP and temephos was similar to that of egg rafts laid on the pot with MSP alone, showing that temephos did not significantly affect MSP activity. The results of the present study highlight the effects of the combined application of MSP with spinosad and diflubenzuron on the oviposition of gravid Cx. p. biotype molestus females, which in

  6. The effect of shade on the container index and pupal productivity of the mosquitoes Aedes aegypti and Culex pipiens breeding in artificial containers.

    Science.gov (United States)

    Vezzani, D; Albicócco, A P

    2009-03-01

    The aim of this study was to assess whether certain attributes of larval breeding sites are correlated with pupal productivity (i.e. numbers of pupae collected per sampling period), so that these could be used as the focus for control measures to enhance control efficiency. Therefore, the objectives were to identify the months of highest pupal productivity of Aedes aegypti (L.) and Culex pipiens L. (Diptera: Culicidae) in an urban temperate cemetery in Argentina where artificial containers of containers and to determine whether the composition of the containers affected pupal productivity. Over a period of 9 months, 200 randomly chosen water-filled containers (100 sunlit and 100 shaded), out of approximately 3738 containers present (approximately 54% in shade), were examined each month within a cemetery (5 ha) in Buenos Aires (October 2006 to June 2007). In total, 3440 immatures of Cx pipiens and 1974 of Ae. aegypti were collected. The larvae : pupae ratio was 10 times greater for the former, indicating that larval mortality was greater for Cx pipiens. Both mosquito species showed a higher container index (CI) in shaded than in sunlit containers (Ae. aegypti: 12.8% vs. 6.9% [chi(2) = 17.6, P container and the number of pupae per pupa-positive container did not differ significantly between sunlit and shaded containers for either species. Therefore, the overall relative productivity of pupae per ha of Ae. aegypti and Cx pipiens was 2.3 and 1.8 times greater, respectively, in shaded than in sunlit areas as a result of the greater CIs of containers in shaded areas. Neither the CI nor the number of immatures per infested container differed significantly among container types of different materials in either lighting condition. The maximum CI and total pupal counts occurred in March for Ae. aegypti and in January and February for Cx pipiens. The estimated peak abundance of pupae in the whole cemetery reached a total of approximately 4388 in the middle of March for Ae

  7. Ecologia de mosquitos (Diptera: Culicidae em criadouros naturais e artificiais de área rural do Norte do Estado do Paraná, Brasil. V. Coleta de larvas em recipientes artificiais instalados em mata ciliar

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    José Lopes

    1997-08-01

    Full Text Available INTRODUÇÃO: A utilização pelos Culicidae de recipientes contendo água para a colocação de seus ovos, em área antropogênica, pode indicar plasticidade genética que os direcione evolutivamente no sentido da domiciliação. Nesse sentido, foram coletadas as diferentes espécies de Culicidae que colonizam recipientes alocados em mata ciliar, na área rural. MATERIAL E MÉTODO: Foram instalados recipientes de pneu, plástico, lata e bambu, em mata ciliar, em área rural no Norte do Paraná, Brasil. RESULTADOS: Coletaram-se larvas de Cx. grupo coronator, Cx. declarator, Cx. laticlasper, Cx. (Melanoconion secção Spissipes, Cx. tatoi, Tr. compressum, Tr. pallidiventer, Ae. terrens, Cx. mollis, Cx. bigoti, Hg. leucocelaenus, Cx. eduardoi, Cx. quinquefasciatus, Li. durhamii e Toxorhynchites sp. As cinco primeiras espécies foram específicas de pneus. As duas espécies de Trichoprosopon ficaram restritas a bambu. Ae. terrens e Cx. mollis foram caletadas em pneu e bambu, Cx. bigoti foi coletada em pneu, lata e bambu, enquanto que Hg. leucocelaenus só não foi encontrada em lata. As quatro últimas espécies foram coletadas em todos os tipos de recipientes. Cx. quinquefasciatus, Cx. eduardoi, Li. durhamii tiveram significante flutuação populacional. CONCLUSÕES: O pneu caracterizou-se como o recipiente mais aceito pelos culicídeos. As áreas onde a mata ciliar esteve mais densa e o locais onde o solo esteve mais úmido foram os pontos com maior número de capturas. A mata ciliar, mesmo muito reduzida e alterada, foi suficiente para abrigar várias espécies de culicídeos. As espécies caputradas podem ser portadoras de plasticidade gênica que as capacitem a colonizar ambientes antropogênicos.

  8. Ecologia de mosquitos (Diptera: Culicidae em criadouros naturais e artificiais de área rural do Norte do Estado do Paraná, Brasil. V. Coleta de larvas em recipientes artificiais instalados em mata ciliar

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    Lopes José

    1997-01-01

    Full Text Available INTRODUÇÃO: A utilização pelos Culicidae de recipientes contendo água para a colocação de seus ovos, em área antropogênica, pode indicar plasticidade genética que os direcione evolutivamente no sentido da domiciliação. Nesse sentido, foram coletadas as diferentes espécies de Culicidae que colonizam recipientes alocados em mata ciliar, na área rural. MATERIAL E MÉTODO: Foram instalados recipientes de pneu, plástico, lata e bambu, em mata ciliar, em área rural no Norte do Paraná, Brasil. RESULTADOS: Coletaram-se larvas de Cx. grupo coronator, Cx. declarator, Cx. laticlasper, Cx. (Melanoconion secção Spissipes, Cx. tatoi, Tr. compressum, Tr. pallidiventer, Ae. terrens, Cx. mollis, Cx. bigoti, Hg. leucocelaenus, Cx. eduardoi, Cx. quinquefasciatus, Li. durhamii e Toxorhynchites sp. As cinco primeiras espécies foram específicas de pneus. As duas espécies de Trichoprosopon ficaram restritas a bambu. Ae. terrens e Cx. mollis foram caletadas em pneu e bambu, Cx. bigoti foi coletada em pneu, lata e bambu, enquanto que Hg. leucocelaenus só não foi encontrada em lata. As quatro últimas espécies foram coletadas em todos os tipos de recipientes. Cx. quinquefasciatus, Cx. eduardoi, Li. durhamii tiveram significante flutuação populacional. CONCLUSÕES: O pneu caracterizou-se como o recipiente mais aceito pelos culicídeos. As áreas onde a mata ciliar esteve mais densa e o locais onde o solo esteve mais úmido foram os pontos com maior número de capturas. A mata ciliar, mesmo muito reduzida e alterada, foi suficiente para abrigar várias espécies de culicídeos. As espécies caputradas podem ser portadoras de plasticidade gênica que as capacitem a colonizar ambientes antropogênicos.

  9. Anofelinos de Santa Catarina (Diptera: Culicidae, Brasil Anophelines of Santa Catarina (Diptera: Culicidae, Brazil

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    Maria da Graça Teixeira Portes

    2010-04-01

    Full Text Available INTRODUÇÃO: No Brasil, a Região Amazônica é endêmica em malária. Em Santa Catarina, a malária foi eliminada na década de 80. A partir daí, ocorreram poucos casos autóctones isolados, e esporádicos. No entanto, em função da existência do vetor em seu território, da existência de extensa área endêmica no Brasil e da grande mobilidade de pessoas em áreas turísticas no estado, existe a probabilidade de reintrodução da doença. MÉTODOS: Utilizou-se os seguintes dados: Banco de Dados do Núcleo de Entomologia da Fundação Nacional de Saúde, Santa Catarina (ACCES,1997-2000; Sistema de Informação de Vigilância Epidemiológica, Secretaria de Vigilância em Saúde (Malária/SC e Sistema de Informação de Notificação e Agravo(SINAN/SC. Os mesmos foram transportados e analisados, no programa Microsoft Office Excel 2007. RESULTADOS: As coletas foram realizadas em 48 municípios, 159 localidades, sendo identificados 12.310 Culicídeos, 11.546 (93,7% Anopheles e 764 (6,2% como outros. Foram identificados três subgêneros e 13 espécies de anofelinos. CONCLUSÕES: Considerando que nos municípios pesquisados, foi identificada a presença de importantes vetores como Anopheles cruzii e Anopheles albitasis e há circulação de pessoas infectadas provenientes de áreas endêmicas, pode-se considerar que os mesmos são áreas receptivas e vulneráveis à malária. Essas espécies são suspeitas de serem responsáveis pela transmissão de malária na região, principalmente nos municípios de Gaspar, Indaial e Rodeio.INTRODUCTION: The Amazon region of Brazil is endemic for malaria. In the State of Santa Catarina, malaria was eliminated in the 1980s. Since then, a few sporadic isolated autochthonous cases have occurred. However, because malaria vectors are present within Brazilian territory and extensive endemic areas exist in this country, along with the great mobility of people in tourist areas of Santa Catarina, there is the likelihood of reintroduction of the disease. METHODS: The following data were used: the database of the Entomology Group of the National Health Foundation, Santa Catarina (ACCES, 1997-2000; the epidemiological surveillance information system of the Health Surveillance Department (Malaria/SC; and the notifiable disease information system (SINAN/SC. These data were transferred to and analyzed in the Microsoft Office Excel 2007 software. RESULTS: Collections were carried out in 48 municipalities and 159 localities, and 12,310 culicids, 11,546 anophelines (93.7% and 764 others (6.2% were identified. Three subgenera and 13 species of anophelines were identified. CONCLUSIONS: Given that in the municipalities investigated, important vectors such as Anopheles cruzii and Anopheles albitasis were found to be present, with movements of infected individuals from endemic areas, these areas can be considered to be receptive and vulnerable to malaria. These species are suspected of being responsible for malaria transmission in this region, especially in the municipalities of Gaspar, Indaial and Rodeio.

  10. Preferência por local de oviposição de Aedes albopictus (Skuse (Diptera, Culicidae, em relação à presença de imaturos da própria espécie, sob condições de laboratório Aedes (Stegomyia albopictus (Skuse (Diptera, Culicidae, preference for oviposition site related with homospecific immatures presence, under laboratory conditions

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    Andreia Aparecida Barbosa

    2002-12-01

    Full Text Available Aedes (Stegomyia albopictus (Skuse, 1894 is an exotic Culicidae species in Brazil. Since its first report in this country, the mosquito has been increasing its geographic distribution. This mosquito is a natural dengue and Japanese Encephalitis virus vector in Asia. The females preference for oviposition sites related with homospecific immature presence was assessed. The experiment was performed with Aedes albopictus from laboratory colony since March ]999, in the Laboratório de Entomologia Médica e Veterinária, Departamento de Zoologia, Universidade Federal do Paraná. The preferred container was the one that kept pupae for 24 hours, with 643 eggs, 30,6% at total. The eggs recipients received 11,45% from total set by the females, and the following numbers to the others: larva 1 (15,79%, larva 2 (14,69%, pupa 1 (20,74%, pupa 2 (30,58%, control (6,75%. Although the ANOVA did not detect significant difference among the treatments, the data possibly indicate that Aedes albopictus prefer laying eggs in containers previously colonized by immature.

  11. Ecologia de mosquitos (Diptera, Culicidae em áreas do Parque Nacional do Iguaçu, Brasil: 1 Distribuição por hábitat

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    Anthony Érico Guimarães

    Full Text Available Estabelecemos a influência exercida pela cobertura vegetal de quatro diferentes biótopos em áreas do Parque Nacional do Iguaçu (PNI sobre a fauna local de mosquitos. Realizaram-se capturas bimestrais, em isca humana e armadilha Shannon, em três diferentes períodos do dia, em ambiente silvestre e domiciliar, durante 24 meses consecutivos. Dentre os 20.273 espécimes de fêmeas adultas capturadas, pertencentes a 44 espécies, Ochlerotatus serratus (10,3%, Haemagogus leucocelaenus (9,7%, Mansonia titillans (9,6% e Chagasia fajardoi (8,8% foram predominantes. Anopheles cruzii, Runchomyia theobaldi, Wyeomyia aporonoma e Wy. confusa ocorreram exclusivamente em áreas com vegetação bem preservada e densa configuração. Culex nigripalpus, Oc. pennai, Oc. serratus, Sabethes purpureus e Sa. albiprivus foram capturados nos três biótopos essencialmente silvestres. Na mata no entorno da represa foram capturadas principalmente An. albitarsis s.l., An. galvaoi, An. evansae, An. fluminensis, Coquillettidia venezuelensis, Cq. juxtamansonia, Wy. quasilongirostris e Onirion personatum. As espécies que apresentaram maiores incidências na área sob ação antrópica foram Ch. fajardoi, Cq. fasciolata, Cq. nitens e Ma. titillans.

  12. Ecologia de mosquitos (Diptera, Culicidae em áreas do Parque Nacional do Iguaçu, Brasil: 1 ­ Distribuição por hábitat

    Directory of Open Access Journals (Sweden)

    Guimarães Anthony Érico

    2003-01-01

    Full Text Available Estabelecemos a influência exercida pela cobertura vegetal de quatro diferentes biótopos em áreas do Parque Nacional do Iguaçu (PNI sobre a fauna local de mosquitos. Realizaram-se capturas bimestrais, em isca humana e armadilha Shannon, em três diferentes períodos do dia, em ambiente silvestre e domiciliar, durante 24 meses consecutivos. Dentre os 20.273 espécimes de fêmeas adultas capturadas, pertencentes a 44 espécies, Ochlerotatus serratus (10,3%, Haemagogus leucocelaenus (9,7%, Mansonia titillans (9,6% e Chagasia fajardoi (8,8% foram predominantes. Anopheles cruzii, Runchomyia theobaldi, Wyeomyia aporonoma e Wy. confusa ocorreram exclusivamente em áreas com vegetação bem preservada e densa configuração. Culex nigripalpus, Oc. pennai, Oc. serratus, Sabethes purpureus e Sa. albiprivus foram capturados nos três biótopos essencialmente silvestres. Na mata no entorno da represa foram capturadas principalmente An. albitarsis s.l., An. galvaoi, An. evansae, An. fluminensis, Coquillettidia venezuelensis, Cq. juxtamansonia, Wy. quasilongirostris e Onirion personatum. As espécies que apresentaram maiores incidências na área sob ação antrópica foram Ch. fajardoi, Cq. fasciolata, Cq. nitens e Ma. titillans.

  13. Atividade de Culicidae em remanescente florestal na região urbana de Curitiba (Paraná, Brasil

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    Barbosa Andréia Aparecida

    2003-01-01

    Full Text Available Vegetation islands inside urban area can propitiate the formation of: a adults refuge to many mosquitoes species, b diversity of hosters, c allows the proliferation of immature stages through naturals and artificial breeding, these ones were done by the interaction between antropic activity developed in these spaces or around areas. Considering the possibilities of contacts between the vector and the human population, the aim of this work was to verify the Culicidae species that can use man as blood source in the restricted areas of Botanical Garden, Curitiba. The capture of adults using the method of human bait at soil level, inside the forest, monthly during the period of October 13th 1998 to September 22nd 1999, from 5:00 p.m. to 8:00 p.m. 312 Culicidae specimens were captured, and 15 species were found. The predomiant species belong to Culex (Culex coronator Dyar & Knab, 1906 group. Others species found with potential epidemiological importance were: Haemagogus (Conopostegus leucocelaenus (Dyar & Shannon, 1924, Ochlerotatus (Ochlerotatus fluviatilis (Lutz, 1904 e Anopheles (Nyssorhynchus strodei Root, 1926.

  14. Culicideofauna (Diptera encontrada em entrenós de taquara de uma mata residual na área urbana de Londrina, Paraná, Brasil Fauna of Culicidae (Diptera found in the internodes of the bamboo in a residual forest in the urban area of Londrina - Paraná, Brazil

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    João Antonio Cyrino Zequi

    2001-06-01

    Full Text Available A fragment of a forest, located in the urban area of Londrina, Paraná, Brazil, was chosen to represent the area for this study. Many Merostachys Spreng, 1824 bamboo, which were naturally perforated and, therefore, ready to retain water, were found in the interior of this forest. Bamboo were collected every fifteen days during field actions. They were then measured and cut meter by meter before their contents were analyzed in the laboratory. A total of 542 specimens from the following species were collected during one year: Sabethes aurescens (Lutz, 1905, Sabethes melanomymphe Dyar, 1924, Sabethes identicus Dyar & Knab, 1907, Wyeomyia rooti (Del Ponte, 1939, Wyeomyia limai Lane & Cerqueira, 1942, Wyeomyia sp., Trichoprosopon pallidiventer (Lutz, 1905, Trichoprosopon humboldti Lane & Cerqueira, 1942, Toxorhynchites sp. e Shannoniana schedocyclium (Dyar & Knab, 1908. Wyeomyia limai and Sabethes aurescens were the most frequently found species. The first specie had the highest population index in february whereas the Sabethes aurescens, had its highest index in july, february and november. The largest number of larvae were obtained in the months of february and march. As for stratification, the greatest quantity of larvae was found at two meters. The specie Wyeomyia limai predominated in all heights, being most abundant at three meters high whereas the Sabethes was most abundant at one meter high. The presence of bamboo in small forest spots in urban areas is enough to host a certain variety of Culicidae of the Sabethini tribe which are considered wild mosquito. These same mosquito, due to their hematophagus habitat, can be hazardous to public health.

  15. Bacillus thuringiensis subsp. sichuansis strain MC28 produces a novel crystal protein with activity against Culex quinquefasciatus larvae.

    Science.gov (United States)

    Guan, Peng; Dai, Xiaojuan; Zhu, Jun; Li, Qiao; Li, Shuangcheng; Wang, Shiquan; Li, Ping; Zheng, Aiping

    2014-04-01

    The Bacillus thuringiensis subsp. sichuansis MC28 strain produces spherical parasporal crystals during sporulation and exhibits remarkable insecticidal activity against dipteran and lepidopteran pests. We characterized a novel cry gene (cry69Aa1), which was found in the pMC95 plasmid of the MC28 strain. The cry69Aa1 gene was inserted into a shuttle vector (pSTK) and expressed in an acrystalliferous mutant B. thuringiensis HD73⁻. In this transformant, a large number of spherical parasporal crystals, which were toxic to Culex quinquefasciatus (Diptera), were formed.

  16. Culex Species Mosquitoes and Zika Virus.

    Science.gov (United States)

    Huang, Yan-Jang S; Ayers, Victoria B; Lyons, Amy C; Unlu, Isik; Alto, Barry W; Cohnstaedt, Lee W; Higgs, Stephen; Vanlandingham, Dana L

    2016-10-01

    Recent reports of Zika virus (ZIKV) isolates from Culex species mosquitoes have resulted in concern regarding a lack of knowledge on the number of competent vector species for ZIKV transmission in the new world. Although observations in the field have demonstrated that ZIKV isolation can be made from Culex species mosquitoes, the detection of ZIKV in these mosquitoes is not proof of their involvement in a ZIKV transmission cycle. Detection may be due to recent feeding on a viremic vertebrate, and is not indicative of replication in the mosquito. In this study, susceptibility of recently colonized Culex species mosquitoes was investigated. The results showed a high degree of refractoriness among members of Culex pipiens complex to ZIKV even when exposed to high-titer bloodmeals. Our finding suggests that the likelihood of Culex species mosquitoes serving as secondary vectors for ZIKV is very low, therefore vector control strategies for ZIKV should remain focused on Aedes species mosquitoes. Our demonstration that Culex quinquefasciatus from Vero Beach, FL, is refractory to infection with ZIKV is especially important and timely. Based on our data, we would conclude that the autochthonous cases of Zika in Florida are not due to transmission by C. quinquefasciatus, and so control efforts should focus on other species, logically Aedes aegypti and Aedes albopictus.

  17. Isolation and sequence analysis of Culex flavivirus from Culex interrogator and Culex quinquefasciatus in the Yucatan Peninsula of Mexico

    Science.gov (United States)

    Saiyasombat, Rungrat; Dorman, Karin S.; Garcia-Rejon, Julian E.; Loroño-Pino, Maria A.; Farfan-Ale, Jose A.

    2010-01-01

    Previously, we reported a high prevalence of Culex flavivirus (CxFV) in Culex quinquefasciatus (Say) in the Yucatan Peninsula of Mexico. To determine whether other Culex spp. mosquitoes in this region are susceptible to natural CxFV infection, Cx. bahamensis (Dyar and Knab), Cx. coronator (Dyar and Knab), Cx. interrogator (Dyar and Knab), Cx. nigripalpus (Theobald) and Cx. opisthopus (Komp) in the Yucatan Peninsula of Mexico were tested for CxFV. Two pools of Cx. interrogator were positive. The envelope protein genes of these isolates and 16 isolates from Cx. quinquefasciatus were sequenced and shown to have ≥99.2% nucleotide identity. These data suggest that there is limited genetic diversity among CxFV isolates in the Yucatan Peninsula of Mexico. PMID:20379749

  18. Susceptibility Status of Anopheles gambiae s.l. (Diptera: Culicidae ...

    African Journals Online (AJOL)

    komla

    Current distribution of a pyrethroid resistance gene (kdr) in malaria vector species of Anopheles gambiae complex from West Africa and further evidence for reproductive isolation of mopti form. Parasitologia 41: 319–. 322. Diabate A., Baldet T. Chandre F., Akogbeto M., Gimiguenide R. T., Darriet F., Bregues C., Guillet P.,.

  19. Seasonal Synchronization of Diapause Phases in Aedes albopictus (Diptera: Culicidae)

    Science.gov (United States)

    Lacour, Guillaume; Chanaud, Lionel; L’Ambert, Grégory; Hance, Thierry

    2015-01-01

    In temperate areas, population dynamics of the invasive Asian tiger mosquito Aedes albopictus are strongly affected by winter. The work we present here analyzes the adaptive synchronization of the diapause process in the wintry generation of A. albopictus, where the egg stage is exposed to adverse winter conditions. The seasonal pattern of egg laying activity of a French Mediterranean population of the Asian tiger mosquito was monitored weekly for 2 years with ovitraps. The field diapause incidence and the critical photoperiod (CPP, i.e. the maternal day length inducing diapause in 50% of the eggs), were determined by hatching experiments on the collected eggs. The period of diapause termination was estimated by a field survey of the first hatchings for both years. The CPP is equal to 13.5 hours of light and occurs in the field on the 25th of August. Thus, it is on September 11th, 17 days after the CPP, that 50% of the eggs are in a prediapause stage in the field. The egg diapause rate increases rapidly during September, whereas the mean number of eggs laid decreases sharply after mid-September. Surprisingly, after having reached a peak of 95% at the end of September, from mid-October the diapause incidence declined and stayed below 50%. Indeed, both years the diapause initiates before the rapid decrease of the environmental temperature. This leaves a sufficient period of time to the complete development of one generation of A. albopictus with effective induction of diapause in the laid eggs. The very first larvae hatched were sampled both years in the first half of March. With 20 to 26 weeks in the egg stage and about 7 weeks in the larval stages, the first annual generation spends a long time in immature stages. On a practical point of view, this long development time represents a wide window for eggs and larvae control in early spring. PMID:26683460

  20. Characterization of anopheline (Diptera: Culicidae) larval habitats in Nouakchott, Mauritania.

    Science.gov (United States)

    Salem, O Ahmedou Salem Mohamed; Khadijetou, M Lekweiry; Moina, M Hasni; Lassana, Konate; Sébastien, Briolant; Ousmane, Faye; Ali, O Mohamed Salem Boukhary

    2013-12-01

    Despite the increasing number of reported autochthonous malaria cases in Nouakchott and the identification of Anopheles arabiensis as the major malaria vector in this Saharan city, anopheline larval habitats have never been identified so far. The objective of this study was to identify and characterize anopheline larval habitats in Nouakchott. During September and October 2012, samples from pools of rainwater, water discharged from standpipes and household drinking water tanks in the districts of Dar Naim, Teyarett and Arafat were analyzed for the presence/absence of anopheline larvae and physicochemical characterization of breeding habitats. Of the 51 prospected water bodies, eight consisting of seven water discharged from standpipes and one household drinking water tank were productive for Anopheles sp. All emerged anopheline mosquitoes from the positive dipping were morphologically identified as members of the An. gambiae complex. Multivariate regression analyses showed that a salinity up to 0.1 g/l and a shaded situation were respectively protective factors against high larval density in breeding sites (adjusted odds ratio = 0.62, 95% CI [0.44-0.87], p = 0.0052 and adjusted odds ratio = 0.56, 95% CI [0.44-0.71, p <0.0001] and a pH up to 7.61 was a risk factor for high larval density in breeding sites (adjusted odds ratio = 1.56, 95% CI [1.25-1.95], p = 0.0001). The study demonstrated in Nouakchott that despite an arid and dry climate, human practices have contributed to the establishment of favourable environmental conditions for the development of anopheline mosquitoes and, therefore, maintaining malaria transmission in this Saharan city. The core malaria vector control intervention as the use of long-lasting insecicidal nets (LLINs) could be complemented in Nouakchott by larval source control. In this area, appropriate larval control measures may be recommended in line with an integrated vector management (IVM) approach.

  1. Genetic Structure of Anopheles (Nyssorhynchus) marajoara (Diptera: Culicidae) in Colombia

    Science.gov (United States)

    2010-01-01

    Salud , Bogotá DC, Colombia; Facultad de Agronomía, Universidad Nacional de Colombia, Ciudad Universitaria, Bogotá DC, Colombia; Division of Entomology...containing 1 × buffer (10 mM Tris-HCl, pH 8.3, 50 mM KCl), 2.5 mM MgCl 2 , 200 μL dideoxy nucleoside triphos- phates (dNTP) , 5 pmol each primer, 0.5 U Taq...Colombia . Manual de Manejo integral de la malaria. Instituto Nacional de Salud Ed . Bogotá, Columbia: Instituto Nacional de Salud . 3. Herrera

  2. Anopheles (Anopheles) pseudopunctipennis Theobald (Diptera: Culicidae): Neotype Designation and Description

    Science.gov (United States)

    2004-01-01

    Especiales de Salud , Bogota, Colombia (DMB), Instituto Biologie “Juan Noe,” Santiago, Chile (IZC), Museo Argentino de Ciencias Naturales, Buenos Aires...fountains, well holes), rice paddies, and marshy meadows. Larvae are found in habitats with acidic, neutral and alkaline water ( pH 4.5Ð8.8), freshwater to

  3. Revision of the Leucosphyrus Group of Anopheles (Cellia) (Diptera, Culicidae)

    Science.gov (United States)

    2005-12-01

    2F. Satun: Khlong Baraket (6o52’N 100o4’E), [0527], 20 Sept. 1965, 1 L (AFRIMS). Songkhala: Sadao , Padang Besa, Khao Rup Chang (6o40’N 100o19’E...Satun Road), Ton Nga Chang Waterfalls (6°56’N 100°19’E), [SL49], 22 Mar. 1965, 2M, 1LePe; [SL88], 27 Mar. 1965, 1L (all above, AFRIMS). Sadao ...S. Inthakone & Y. Sato . 1997. Collection of anopheline mosquitos in three villages endemic for malaria in Khammouane, Lao PDR. The Southeast Asian

  4. Mosquitoes (Diptera: Culicidae) Captured in the Iquitos Area of Peru

    Science.gov (United States)

    1993-01-01

    SECURITY CLA~rIFICATION OF THIS PAGE REPORT DOCUMENTATION PAGE lb. RESTRICTIVE MARKINGSAD- A266 518It 3. DISTRIBUTION /AVAILABILITY OF REPORT 2lilii...Continue on reverse if necessary and identify by block number) MOL EECTE8 J UL 07 1993 93-1529n 93 7 06 005 MINOwR 20. DISTRIBUTION IAVAILABILITY OF...X X X X, Xd X X 40d 40d Sabethes belizarioi Neiva 1 - 1 -. . . . X - - Sabetheni tribe 834 23 857 - X X X X, Xd - - Toxorhynchites sp. I - I

  5. Updated Checklist of the Mosquitoes (Diptera: Culicidae) of French Guiana.

    Science.gov (United States)

    Talaga, Stanislas; Dejean, Alain; Carinci, Romuald; Gaborit, Pascal; Dusfour, Isabelle; Girod, Romain

    2015-09-01

    The incredible mosquito species diversity in the Neotropics can provoke major confusion during vector control programs when precise identification is needed. This is especially true in French Guiana where studies on mosquito diversity practically ceased 35 yr ago. In order to fill this gap, we propose here an updated and comprehensive checklist of the mosquitoes of French Guiana, reflecting the latest changes in classification and geographical distribution and the recognition of current or erroneous synonymies. This work was undertaken in order to help ongoing and future research on mosquitoes in a broad range of disciplines such as ecology, biogeography, and medical entomology. Thirty-two valid species cited in older lists have been removed, and 24 species have been added including 12 species (comprising two new genera and three new subgenera) reported from French Guiana for the first time. New records are from collections conducted on various phytotelmata in French Guiana and include the following species: Onirion sp. cf Harbach and Peyton (2000), Sabethes (Peytonulus) hadrognathus Harbach, Sabethes (Peytonulus) paradoxus Harbach, Sabethes (Peytonulus) soperi Lane and Cerqueira, Sabethes (Sabethinus) idiogenes Harbach, Sabethes (Sabethes) quasicyaneus Peryassú, Runchomyia (Ctenogoeldia) magna (Theobald), Wyeomyia (Caenomyiella) sp. cf Harbach and Peyton (1990), Wyeomyia (Dendromyia) ypsipola Dyar, Wyeomyia (Hystatomyia) lamellata (Bonne-Wepster and Bonne), Wyeomyia (Miamyia) oblita (Lutz), and Toxorhynchites (Lynchiella) guadeloupensis (Dyar and Knab). At this time, the mosquitoes of French Guiana are represented by 235 species distributed across 22 genera, nine tribes, and two subfamilies. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Short Report: Anopheles darlingi (Diptera: Culicidae) in Panama

    Science.gov (United States)

    Loaiza, Jose; Scott, Marilyn; Bermingham, Eldredge; Rovira, Jose; Sanjur, Oris; Conn, Jan E.

    2009-01-01

    We report Anopheles darlingi in Darien Province in eastern Panama. Polymerase chain reaction–restriction fragment length polymorphism profiles of the single copy nuclear white gene and sequence comparisons confirmed the presence of 66 specimens of the northern lineage of An. darlingi. The parsimony network depicted 5 CO1 haplotypes in 40 specimens of An. darlingi, which connected through 7–8 mutational steps with sequences from Central and South America. Furthermore, the presence of haplotypes in Biroquera, Darien Province identical to those previously published from northern Colombia suggests that Panamanian samples originated in Colombia. Results of neutrality tests (R2 and Fu’s FS) were not significant and the mismatch distribution was multimodal and did not fit the model of sudden population growth. These findings may indicate a long and stable presence of An. darlingi in eastern Panama. PMID:19556561

  7. Genetic Structure of Anopheles (Nyssorhynchus) marajoara (Diptera: Culicidae) in Colombia

    Science.gov (United States)

    Brochero, Helena; Li, Cong; Wilkerson, Richard; Conn, Jan E.; Ruiz-García, Manuel

    2010-01-01

    Five Anopheles marajoara Galvão and Damasceno populations, representing diverse ecological conditions, were sampled throughout Colombia and analyzed using nine hypervariable DNA microsatellite loci. The overall genetic diversity (H = 0.58) was lower than that determined for some Brazilian populations using the same markers. The Caquetá population (Colombia) had the lowest gene diversity (H = 0.48), and it was the only population at Hardy–Weinberg equilibrium. Hardy–Weinberg disequilibrium in the remaining four populations was probably caused by the Wahlund effect. The assignment analyses showed two incompletely isolated gene pools separated by the Eastern Andean cordillera. However, other possible geographical barriers (rivers and other mountains) did not play any role in the moderate genetic heterogeneity found among these populations (FST = 0.069). These results are noteworthy, because this species is a putative malaria vector in Colombia. PMID:20810825

  8. Susceptibility Status of Anopheles gambiae s.l. (Diptera: Culicidae ...

    African Journals Online (AJOL)

    komla

    susceptible 'Kisumu' strain, both Korle-Bu and Airport populations were highly resistant to DDT and gave resistance levels which were over nine-fold for permethrin and over 2.5-fold for deltamethrin. Both wild and susceptible populations showed full susceptibility to malathion. The S and M forms of A. gambiae s.s. were ...

  9. Susceptibility status of Anopheles gambiae s.l. (Diptera: Culicidae ...

    African Journals Online (AJOL)

    susceptible 'Kisumu' strain, both Korle-Bu and Airport populations were highly resistant to DDT and gave resistance levels which were over nine-fold for permethrin and over 2.5-fold for deltamethrin. Both wild and susceptible populations showed full susceptibility to malathion. The S and M forms of A. gambiae s.s. were ...

  10. [Detection of Anopheles artemievi (Diptera, Culicidae) in Uzbekistan].

    Science.gov (United States)

    Zhakhongirov, Sh M; Muminov, M S; Ponomarev, I M; Shokirov, M K

    2011-01-01

    An. artemievi was diagnosed by morphological and molecular genetic analyses in the Fergana valley, Uzbekistan, in 2008-2009. Four species of the genus Anopheles: An. superpictus, An. artemievi, An. hyrcanus, and An. claviger inhabiting the irrigated oases with the bulk of population were detected in the Fergana valley. An. artemievi and An. superpictus were prevalent in the foci of malaria. An. artemievi larvae inhabited the rice fields, springs, collection-drainage systems, and water reservoirs enriched in oxygen. The most attractive day's rest for mosquitoes was a cattle house where their bulk (on average 41.8%) was present. Next was cattle sheds, with the mosquitoes averaging 26.4%. An. artemievi, attacked human beings in the field conditions. This species showed a high susceptibility to test insecticides, such as propoxur, cipermethrin, deltamethrin, and lambda-Cyhalothrin.

  11. Evidence of seasonal eggs in Anopheles punctipennis (Diptera: Culicidae).

    Science.gov (United States)

    Fritz, G N; Washino, R K

    1992-07-01

    Anopheles punctipennis (Say), collected in October from resting sites in Illinois, deposited two morphologically distinct types of egg batches. One type was similar to the seasonal "winter" egg of Anopheles walkeri Theobald, with an extensive exochorion that covered all except the tip of the egg. Laboratory rearing of isofemale lines, under two different light-dark and temperature cycles, demonstrated that both types of eggs were intraspecific variants. F1 females from all "winter" egg batches deposited only normal eggs when reared under a 12:12 (L:D) cycle and at 25 degrees C. Most An. punctipennis reared under a 8:16 (L:D) cycle with variable temperature exhibited gonotrophic dissociation or accumulated fat body.

  12. Prey density effect on cannibalism by Toxorhynchites towadensis (Diptera: Culicidae).

    Science.gov (United States)

    Yasuda, H; Hashimoto, T

    1995-09-01

    The effect of prey density on cannibalism by the larvae of Toxorhynchites towadensis (Matsumura) was studied in the laboratory. Frequency of cannibalism was compared among pairs of all possible instar combinations of Tx. towadensis in the presence and absence of Aedes albopictus (Skuse). Cannibalism occurred despite the presence of prey larvae, but more frequently between different instars than the same instars. Cannibalized larvae were always younger than or the same age as their attackers. Six predatory larvae were reared in a container with 30, 60, or 120 prey throughout their development, and cannibalism and development were observed. No cannibalism was observed when prey density was 120. However, in the continuous presence of 30 prey, cannibalism occurred on 8 occasions. Cannibalism at a prey density of 60 was intermediate in frequency. Most (92%) cannibalism occurred when 1st or 2nd instars attacked the same or younger instars. The time in cohabitation of different instars was shorter with increasing prey density.

  13. First record of Toxorhynchites rutilus (Diptera: Culicidae) in Massachusetts.

    Science.gov (United States)

    Dennehy, J J; Livdahl, T

    1999-09-01

    The 1st recorded capture of Toxorhynchites rutilus in Massachusetts, USA, is reported. This capture represents the northernmost record of Tx. rutilus. The implications of this capture are discussed in the context of range expansion, evolution, and climatic change.

  14. New species of Toxorhynchites (Diptera: Culicidae) from Macau (China).

    Science.gov (United States)

    Ribeiro, H

    1997-09-01

    The male holotype and female allotype of Toxorhynchites (Toxorhynchites) macaensis Ribeiro, a new mosquito species from Macau, southern China, are described on the basis of the examination of a type series of 6 males and 7 females. Similarities of the new species with the other species of the Splendens group, to which the new taxon belongs, are discussed and keys to identification of males and females of all the species of the group are provided.

  15. Cannibalism and carnivory in Toxorhynchites splendens (Diptera: Culicidae).

    Science.gov (United States)

    Amalraj, D D; Das, P K

    1992-09-01

    Laboratory reared larvae of Toxorhynchites splendens, which were previously starved for 24 hours, cannibalized eggs of their own kind or preyed upon the eggs of other species (Aedes aegypti and Anopheles stephensi) present on the surface of water in small containers. Second and third instars consumed eggs faster than first and fourth instars. The first instar consumed larvae of its own kind faster than the other instars, in the absence of other prey. However, when prey larvae were provided, there was a significant fall in the rate of cannibalism.

  16. Studies on Anopheles (Kerteszia) homunculus Komp (Diptera: Culicidae)

    Science.gov (United States)

    2009-01-01

    22202-4302. Respondents should be aware that notwithstanding any other provision of law , no person shall be subject to a penalty for failing to comply...by the Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP (Grant 05/53973-0), and Conselho Nacional de Desenvolvimento Técnico e Científico

  17. The neotype of anopheles albitarsis (Diptera: culicidae O neótipo de Anopheles albitarsis (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Maria Goreti Rosa-Freitas

    1989-09-01

    Full Text Available Anopheles albitarsis neotype is described from specimens collected in Baradero, Argentina, in Shannon's trap, in horse and pig stables and on the progeny of engorded females. The description includes illustrations of adult female, male and female genitalias, scanning electron miscroscopy of the eggs and complete chaetotaxy of pupa and larva. The importance for electing a neotype is based on the realization that An. albitarsis is a complex of cryptic species. It is an attempt to provide typt-locality specimens with which other memebers of the group can be compared.O neótipo de Anopheles albitarsis é descrito a partir de espécimens coletados em armadilha tipo Shannon, em estábulos de cavalos e porcos e progênies de fêmeas ingurgitadas em Baradero, Argentina, localidade-tipo da espécie. A descrição inclui ilustrações da fêmea adulda, genitálias masculina e feminina, ovos em microscopia eletrônica de varredura e da quetotaxia completa das larvas de 4º estádio e pupas. A eleição de um neótipo para albitarsis baseia-se em dados recentes que apontam a espécie como um complexo de espécies crípticas, o que evidencia a importância de uma descrição detalhada de espécimens da localidade-tipo com o qual outros membros do grupo possam ser comparados.

  18. Effects of developmental asynchrony between Aedes triseriatus (Diptera:Culicidae) and its predator Toxorhynchites rutilus (Diptera:Culicidae).

    Science.gov (United States)

    Nannini, M A; Juliano, S A

    1997-07-01

    Newly hatched Toxorhynchites rutilus (Coquillet) were added to experimental populations of Aedes triseriatus (Say) at varying days after prey hatch to test the hypothesis that a developmental asynchrony of Ae. triseriatus and Tx. rutilus leads to escape from predation by Ae. triseriatus in small water bodies. Presence of Tx. rutilus significantly affected prey survivorship. Regression of survivorship [log10 (x + 1) transformed] versus days head start for prey yielded a small, but significant positive slope, indicating that survivorship increased slightly with an increasing number of days head start. For females, mean weight at emergence was not significantly affected by treatments; however, median days to emergence differed significantly between the treatments, with females taking significantly longer to emerge with Tx. rutilus absent than when the predator was present. For males, neither mean mass nor median days to emergence was significantly affected by treatments. Treatments had no significant effect on the frequency of deaths or on mean weight of Tx. rutilus. Thus, a developmental asynchrony between Tx. rutilus and Ae. Triseriatus appears to have no effects on the predator, but does have a weak effect on prey performance at high hatch densities.

  19. Morphometric studies on Culex quinquefasciatus and Mansonia ...

    African Journals Online (AJOL)

    The objective was to investigate possible morphological differences in populations of Culex quinquefasciatus and Mansonia africana. Six morphological characters namely, wing length, antennal length, proboscis length, foreleg length, mid leg length and hind leg length were measured in the two species. A total of 868 Cx ...

  20. Controle de Aedes (Stegomyia aegypti (Linnaeus, 1762 e Culex (Culex quinquefasciatus Say, 1823 através de formulados contendo Bacillus thuringiensis israelensis em temperaturas controladas

    Directory of Open Access Journals (Sweden)

    João Zequi

    2011-11-01

    Abstract. Aedes (Stegomyia aegypti (Linnaeus and Culex (Culex quinquefasciatus Say are important pathogen vectors in urban environments. This study was designed to evaluate commercial formulations containing Bacillus thuringiensis israelensis de Barjac for the control of Ae. aegypti and Cx. quinquefasciatus and to assess their efficiency as compared to manufacturers´ claims. The tested products were the liquid formulation of Aquabac® XT 1200 ITU/mg, Teknar® 3000AAU/mg, and Vectobac® AS 1200 ITU/mg, and the solid products Vectobac® WDG 3000 ITU/mg, Vectobac® Tablet 2200 ITU/mg, and the trial formulation of Biouel 500 ITU/mg. All products were tested at 25±2°C temperature and the liquid formulations were also tested at 15±2°C, 35±2°C, and at room temperature (25.37 to 28.73ºC. The experiments were conducted with 25 larvae at the early 4th stage, in 150 mL of distilled water; the dead larvae were counted 24 hours after product application. Results were analyzed using Probit to calculate CL50. The 25±2°C temperature, Vectobac WDG, and Vectobac Tablet were the most efficient in controlling Ae. aegypti, with CL50 of 0.10 (0.08 – 0.11 mg/L and 0.10 (0.09 – 0.11 mg/L, respectively. The most efficient products for Cx. quinquefasciatus were Vectobac WDG, Vectobac AS, Biouel, and Vectobac T. When the potency claimed by manufacturers was compared to our laboratory results, Biouel had the best performance for both species. Vectobac AS was the most efficient for both species of Culicidae tested at 15±2°C, 35±2°C and at room temperature (25.37 to 28.37°C. Lower product concentrations were required at 35±2°C room temperature to control Cx. quinquefasciatus than for Ae. aegypti.

  1. The ultrastructure of oogenesis in Culex theileri

    African Journals Online (AJOL)

    of deposition of the yolk in the oocyte. In Diptera, vitel- logenin, a unique group of proteins synthesized extra-ovarially, are only synthesized after the ingestion of a vertebrate blood meal (Hagedorn 1974). While oogenesis in mosquitoes has been studied (Anderson & Spielman 1971; Mathew & Rai. 1975; Roth & Porter 1964 ...

  2. Evaluation préliminaire de l'activité larvicide des extraits aqueux des feuilles du ricin (Ricinus communis L. et du bois de thuya (Tetraclinis articulata (Vahl Mast. sur les larves de quatre moustiques culicidés : Culex pipiens (Linné, Aedes caspius (Pallas, Culiseta longiareolata (Aitken et Anopheles maculipennis (Meigen

    Directory of Open Access Journals (Sweden)

    Mahari S.

    2006-01-01

    Full Text Available Preliminary evaluation of larvicidal activity of aqueous extracts from leaves of Ricinus communis L. and from wood of Tetraclinis articulata (Vahl Mast. on the larvae of four mosquito species: Culex pipiens (Linné, Aedes caspius (Pallas, Culiseta longiareolata (Aitken and Anopheles maculipennis (Meigen. Aqueous extracts of Ricinus communis leaves and Tetraclinis articulata wood showed strong toxic activity against larvae of several mosquitoes. In this study, insecticide effects of these plant extracts have been investigated on 2nd and 4th instars larvae of Culicidae insects, Culex pipiens (Linné, Aedes caspius (Pallas, Culiseta longiareolata (Aitken and Anopheles maculipennis (Meigen. After 24 hours of exposition, bioassays revealed low lethal concentrations LC50. To control mosquitoes, these plant extracts might be used as natural biocides.

  3. Diving beetles (Dytiscidae) as predators of mosquito larvae (Culicidae) in field experiments and in laboratory tests of prey preference.

    Science.gov (United States)

    Lundkvist, E; Landin, J; Jackson, M; Svensson, C

    2003-06-01

    Field experiments were performed in artificial ponds to evaluate how the density of predatory diving beetles (Dytiscidae) would affect the population levels of mosquito larvae (Culicidae). Mosquitoes colonizing the ponds were predominantly species of the genus Culex. In 2000, most of the dytiscids colonizing the ponds were small (Hydroporus spp.), and these predators had no impact on the size of larval mosquito populations, not even in ponds with added dytiscids. In 2001, larger beetles (Ilybius, Rhantus, and Agabus spp.) were more common, and there were significantly fewer mosquito larvae in ponds with the highest numbers of dytiscids. There was a negative correlation between numbers of diving beetles in the ponds and the mean body length of mosquito larvae. In neither year could dytiscid densities be maintained above a certain level owing to emigration. In laboratory tests, there were marked differences between three common dytiscid species in regard to preferences for Daphnia and Culex species as prey: Colymbetes paykulli Erichson chose mosquito larvae more often, whereas both Ilybius ater (De Geer) and I. fuliginosus (Fabricius) preferred Daphnia spp. All of the tested dytiscids consumed large numbers of prey. Since some dytiscid species can efficiently decrease populations of mosquito larvae, they are probably important in the natural control of these dipterans.

  4. Alguns aspectos da ecologia dos mosquitos (Diptera: Culicidae de uma área de planície (granjas Calábria em Jacarepaguá, Rio de Janeiro: IV. Preferências alimentares quanto ao hospedeiro e freqüência domiciliar Some aspects of the ecology of the mosquities (Diptera: Culicidade of an area of plains (grange Calabria in Jacarepaguá, Rio de Janeiro: IV. Food preferences of hosts and domiciliary frequency

    Directory of Open Access Journals (Sweden)

    Ricardo Lourenço-de-Oliveira

    1986-03-01

    Full Text Available Apresentamos os resultados de capturas de mosquitos, realizadas entre janeiro de 1982 e março de 1983, em Granjas Calábria, com a finalidade de avaliar suas preferências alimentares. Usamos seis iscas: homem, cavalo, vaca, carneiro, galo e sapo. O cavalo atraiu o maior número de exemplares, seguindo-se a vaca, o homem, o galo e o carneiro, sendo que o sapo não foi atacado. A isca humana foi a que atraiu mais espécies. Observamos uma tendência zoófila para as espécies locais - An. albitarsis, An. aquasalis, Ae. scapularis, Ae. taeniorhynchus, Cq. venezuelensis, Ma. titillans, Ps. ciliata, Ph. davisi e Ph. deanei sugaram principalemte cavalo e vaca, enquanto os Culex do subgênero Culex pareceram-nos mais ornitófilos e os do subgênero Microculex preferiram animais pecilotérmicos em experimentos que realizamos no laboratório. Ma. titillans foi a espécie preponderante em todas as iscas, demonstrado elevado ecletismo. Para estudar a freqüência domiciliar e peridomiciliar fizemos, mensalmente, de agosto de 1981 a julho de 1982, capturas dentro e fora de uma casa. Excetuando algumas espécies com maior propensão à endofilia principalmente An. aquasalis e Cx. quinquefasciatus, os mosquitos locais mostram-se mais exófilos. Foram visitantes ocasionais do domicílo: Ma. titillans, Ae. scapularis, Ae. taeniorhynchus e Cx. saltanensis.Results are presented on mosquito catches performed between january 1982 and March 1983, in Granjas Calábria, Rio de Janeiro, Brazil, in order to evaluate their host preferences. We used six baits, man, horse, cow, sheep, cock and toad. Horse attracted the greatest number of mosquitoes, followed by cow, man, cock and sheep, no mosquito fed on toad. man was the bait which attracted the largest number of species. Most local species were definetely zoophilic - An. albitarsis, An. aquasalis, Ae. scapularis, Ae. taeniorhynchus, Cq. venezuelensis, Ma. titillans, Ps. ciliata, ph. davisi and Ph. deanei preferred

  5. The impact of CO2 on collection of Aedes aegypti (Linnaeus) and Culex quinquefasciatus Say by BG-Sentinel(r) traps in Manaus, Brazil

    Science.gov (United States)

    de Ázara, Tatiana Mingote Ferreira; Degener, Carolin Marlen; Roque, Rosemary Aparecida; Ohly, Jörg Johannes; Geier, Martin; Eiras, Álvaro Eduardo

    2013-01-01

    Carbon dioxide (CO2) is an important component for activating and attracting host-seeking mosquitoes. The BG-Sentinel(r) trap is a well-established monitoring tool for capturing Culicidae, but CO2 role for the trap effectiveness has not been evaluated in highly urbanised areas. The objective was to evaluate the effectiveness of BG-Sentinel traps baited with and without CO2 for capturing urban mosquitoes. Fifteen areas were selected within the city of Manaus, Brazil, where four BG-Sentinels were operated for 24 h, two of them with CO2 and two without CO2. Captured Aedes aegypti females were dissected for the determination of their parity status. A significantly higher proportion of traps (from 32-79%) were positive for female Ae. aegypti when using the BG-Sentinel with CO2 (χ2 = 11.0271, p ≤ 0.001). Catches of female Culex spp were six times higher in CO2 traps (Mann-Whitney U test = 190.5; p = 0.001). Parity rates were similar for both traps. This study showed that CO2 has primarily an enhancing effect on the efficacy of BG-Sentinel for capturing Culex spp in Manaus. For Ae. aegypti, the positivity rate of the trap was increased, when CO2 was added. PMID:23579804

  6. The impact of CO2 on collection of Aedes aegypti (Linnaeus) and Culex quinquefasciatus Say by BG-Sentinel® traps in Manaus, Brazil.

    Science.gov (United States)

    de Ázara, Tatiana Mingote Ferreira; Degener, Carolin Marlen; Roque, Rosemary Aparecida; Ohly, Jörg Johannes; Geier, Martin; Eiras, Álvaro Eduardo

    2013-04-01

    Carbon dioxide (CO2) is an important component for activating and attracting host-seeking mosquitoes. The BG-Sentinel® trap is a well-established monitoring tool for capturing Culicidae, but CO2 role for the trap effectiveness has not been evaluated in highly urbanised areas. The objective was to evaluate the effectiveness of BG-Sentinel traps baited with and without CO2 for capturing urban mosquitoes. Fifteen areas were selected within the city of Manaus, Brazil, where four BG-Sentinels were operated for 24 h, two of them with CO2 and two without CO2. Captured Aedes aegypti females were dissected for the determination of their parity status. A significantly higher proportion of traps (from 32-79%) were positive for female Ae. aegypti when using the BG-Sentinel with CO2 (χ2 = 11.0271, p ≤ 0.001). Catches of female Culex spp were six times higher in CO2 traps (Mann-Whitney U test = 190.5; p = 0.001). Parity rates were similar for both traps. This study showed that CO2 has primarily an enhancing effect on the efficacy of BG-Sentinel for capturing Culex spp in Manaus. For Ae. aegypti, the positivity rate of the trap was increased, when CO2 was added.

  7. The impact of CO2 on collection of Aedes aegypti (Linnaeus and Culex quinquefasciatus Say by BG-Sentinel(r traps in Manaus, Brazil

    Directory of Open Access Journals (Sweden)

    Tatiana Mingote Ferreira de Ázara

    2013-04-01

    Full Text Available Carbon dioxide (CO2 is an important component for activating and attracting host-seeking mosquitoes. The BG-Sentinel(r trap is a well-established monitoring tool for capturing Culicidae, but CO2 role for the trap effectiveness has not been evaluated in highly urbanised areas. The objective was to evaluate the effectiveness of BG-Sentinel traps baited with and without CO2 for capturing urban mosquitoes. Fifteen areas were selected within the city of Manaus, Brazil, where four BG-Sentinels were operated for 24 h, two of them with CO2 and two without CO2. Captured Aedes aegypti females were dissected for the determination of their parity status. A significantly higher proportion of traps (from 32-79% were positive for female Ae. aegypti when using the BG-Sentinel with CO2 (χ2 = 11.0271, p ≤ 0.001. Catches of female Culex spp were six times higher in CO2 traps (Mann-Whitney U test = 190.5; p = 0.001. Parity rates were similar for both traps. This study showed that CO2 has primarily an enhancing effect on the efficacy of BG-Sentinel for capturing Culex spp in Manaus. For Ae. aegypti, the positivity rate of the trap was increased, when CO2 was added.

  8. Toxicity and Synergistic Activities of Chalcones Against Aedes aegypti (Diptera: Culicidae) and Drosophila melanogaster (Diptera: Drosophilidae).

    Science.gov (United States)

    Gross, Aaron D; Tabanca, Nurhayat; Islam, Rafique; Ali, Abbas; Khan, Ikhlas A; Kaplancikli, Zafer A; Altintop, Mehlika D; Ozdemir, Ahmet; Bloomquist, Jeffrey R

    2017-03-01

    Mosquito-borne illnesses are of great concern throughout the world, and chemical insecticides are commonly employed to decrease mosquito populations. However, the developmental insecticide pipeline for vector control has primarily been filled by repurposed agricultural products, and is hampered by their widespread use and insecticide resistance. The present study was performed in the search for new chemical insecticides or insecticide synergists. Screening of 31 chalcone analogs was performed using Aedes aegypti (Linnaeus) first-instar larval toxicity assay, and oral feeding to Drosophila melanogaster's proper authority should be (Meigen). Synergism studies were performed by topically applying chalcones to adult female Ae. aegypti mosquitoes to examine its impact on activity of carbaryl, which was compared to piperonyl butoxide alone. Fourteen chalcone analogs had LC50 values in the range of 0.4-38 ppm against first-instar Ae. aegypti larvae, and three chalcones displayed toxicity against D. melanogaster via feeding (LC50 values ranged from 146-214 μg/ml). Two chalcones synergized carbaryl toxicity against adult Ae. aegypti with efficacy similar to piperonyl butoxide. As a result, it is concluded that chalcones may serve as novel insecticides and synergists after further structural optimization. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Toxicity and synergistic activities of Chalcones against Aedes aegypti (Diptera: Culicidae) and Drosophila melanogaster (Diptera: Drosophilidae)

    Science.gov (United States)

    Mosquito-borne illnesses are of great concern throughout the world, and chemical insecticides are commonly employed to decrease mosquito populations. However, the developmental insecticide pipeline for vector control has primarily been filled by repurposed agricultural products, and is hampered by t...

  10. ANCAMAN DARI NYAMUK Culex sp YANG TERABAIKAN

    Directory of Open Access Journals (Sweden)

    Zumrotus Sholichah

    2012-11-01

    Full Text Available Nyamuk Culex sp lebih menyukai meletakkan telurnya pada genangan air berpolutan tinggi, berkembang biak di air keruh dan lebih menyukai genangan air yang sudah lama daripada genangan air yang baru. Aktif menggigit pada malam hari. Tempat yang gelap, sejuk dan lembab merupakan tempat yang disukai untuk beristirahat. Nyamuk betina dewasa menggigit dengan abdomen terletak sejajar dengan permukaan induk semang yang sedang digigit.Gangguan yang ditimbulkan oleh nyamuk selain dapat menularkan penyakit juga dapat sangat mengganggu dengan dengungan dan gigitannya sehingga bagi orang-orang tertentu dapat menimbulkan phobi (entomopobhia serta dapat menyebabkan dermatitis dan urticaria.

  11. First Nationwide Surveillance of Culex pipiens Complex and Culex torrentium Mosquitoes Demonstrated the Presence of Culex pipiens Biotype pipiens/molestus Hybrids in Germany

    Science.gov (United States)

    Börstler, Jessica; Melaun, Christian; Jöst, Hanna; von Thien, Heidrun; Badusche, Marlis; Becker, Norbert; Schmidt-Chanasit, Jonas; Krüger, Andreas; Tannich, Egbert; Becker, Stefanie

    2013-01-01

    Mosquitoes and other arthropods may transmit medically important pathogens, in particular viruses such as West Nile virus. The presence of suitable hosts and competent vectors for those zoonotic viruses is essential for an enzootic transmission, which is a prerequisite for epidemics. To establish reliable risk projections, it is an urgent need for an exact identification of mosquito species, which is especially challenging in the case of sibling species, such as Culex. pipiens pipiens biotypes pipiens and molestus. To facilitate detection of different Culex pipiens forms and their hybrids we established a multiplex real-time PCR. Culex pipiens samples were obtained by egg raft collection and rearing until imago stage or adult sampling using CO2 baited traps and gravid traps. In total, we tested more than 16,500 samples collected all over Germany in the years 2011 and 2012. The predominant species in Germany are Culex pipiens pipiens biotype pipiens and Culex. torrentium, but we also detected Culex pipiens pipiens biotype molestus and hybrids of the two pipiens biotypes at sites where both species occur sympatrically. This report of a potentially important bridge vector for West Nile virus might have major impact in the risk projections for West Nile virus in Germany. PMID:24039724

  12. Development of a Multiplexed Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) Assay to Identify Common Members of the Subgenera Culex (Culex) and Culex (Phenacomyia) in Guatemala

    OpenAIRE

    Kent, Rebekah J.; Deus, Stephen; Williams, Martin; Savage, Harry M.

    2010-01-01

    Morphological differentiation of mosquitoes in the subgenera Culex (Culex) and Culex (Phenacomyia) in Guatemala is difficult, with reliable identification ensured only through examination of larval skins from individually reared specimens and associated male genitalia. We developed a multiplexed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay to identify common Cx. (Cux.) and Cx. (Phc.). Culex (Cux.) chidesteri, Cx. (Cux.) coronator, Cx. (Cux.) interrogator...

  13. Occurrence of Borrelia burgdorferi s.l. in different genera of mosquitoes (Culicidae) in Central Europe.

    Science.gov (United States)

    Melaun, Christian; Zotzmann, Sina; Santaella, Vanesa Garcia; Werblow, Antje; Zumkowski-Xylander, Helga; Kraiczy, Peter; Klimpel, Sven

    2016-03-01

    Lyme disease or Lyme borreliosis is a vector-borne infectious disease caused by spirochetes of the Borrelia burgdorferi sensu lato complex. Some stages of the borrelial transmission cycle in ticks (transstadial, feeding and co-feeding) can potentially occur also in insects, particularly in mosquitoes. In the present study, adult as well as larval mosquitoes were collected at 42 different geographical locations throughout Germany. This is the first study, in which German mosquitoes were analyzed for the presence of Borrelia spp. Targeting two specific borrelial genes, flaB and ospA encoding for the subunit B of flagellin and the outer surface protein A, the results show that DNA of Borrelia afzelii, Borrelia bavariensis and Borrelia garinii could be detected in ten Culicidae species comprising four distinct genera (Aedes, Culiseta, Culex, and Ochlerotatus). Positive samples also include adult specimens raised in the laboratory from wild-caught larvae indicating that transstadial and/or transovarial transmission might occur within a given mosquito population. Copyright © 2015 Elsevier GmbH. All rights reserved.

  14. X-ray diffraction pattern from the flight muscle of Toxorhynchites towadensis reveals the specific phylogenic position of mosquito among Diptera.

    Science.gov (United States)

    Iwamoto, Hiroyuki

    2015-01-01

    The Diptera are a group of insects with only a single pair of wings (forewings), and are considered monophyletic (originating from a common ancestor). The flight muscle in Diptera has features not observed in other insects, such as the long Pro-Ala-rich peptide associated with tropomyosin, not with troponin-I as in other insects, and the formation of a superlattice by myosin filaments analogous to that in vertebrate skeletal muscle. Here we describe X-ray diffraction patterns from the flight muscle of a mosquito, Toxorhynchites towadensis (Culicidae), belonging to a primitive group of Diptera. The diffraction pattern indicates that myosin filaments in the flight muscle of this species do not form a superlattice. X-ray diffraction also shows meridional reflections that are not observed in other dipterans, but are present in the patterns from bumblebee (Hymenoptera) flight muscle. These observations suggest that the superlattice structure evolved after the common ancestor of Diptera had diverged from other insects. The flight muscle of mosquito may retain primitive structural features that are shared by Hymenoptera.

  15. Composição da fauna de Anopheles (Díptera : Culicidae) da reserva indígena do Ocoy

    OpenAIRE

    Araujo, Roderlei de

    2012-01-01

    Resumo: A malária no Estado do Paraná deve-se principalmente ao fluxo de pessoas advindas de áreas endêmicas de outras regiões do país, e a manutenção do vetor transmissor em algumas regiões do estado onde, o risco para ocorrência de casos autóctones da doença inspira cuidado. O presente estudo teve por objetivo descrever a composição da fauna de Anopheles (Diptera: Culicidae) da Reserva Indígena do Ocoy, foco ativo de malária no município de São Miguel do Iguaçu. As análises foram feitas atr...

  16. Occurrence of immature forms of culicids (Insecta: Diptera in the northeastern region of Brazil

    Directory of Open Access Journals (Sweden)

    Cristiane Maia da Silva

    Full Text Available The Culicidae family is represented by approximately 3,610 species, among which many are involved in transmission of pathogens and parasites, thus presenting great medical-veterinary importance. In Brazil, the state of Pernambuco is considered an endemic area for many diseases vectored by mosquitoes, such as human and canine filariasis, caused by Wuchereria bancrofti and Dirofilaria immitis, respectively. The aim of this study was to evaluate the occurrence of immature forms of culicids, over an one-year period, in a specific area of northeastern region of Brazil. Culicids larvae were collected from traps located on the ground and in treetops, between october 2012 and september 2013. Ten different species of culicids were identified. The greatest number of larvae were collected in september 2013 and the lowest number in december 2012. Stegomyia (Stegomyia albopicta (46.45%; 5,908/12,718, Culex (Culex maxi (35.56%; 4,523/12,718 and Limatus durhamii (12.58%; 1,600/12,718 were the most frequent species. The human and animal populations living in the study area are exposed to culicids and transmission agents throughout the year, especially after the rains. Therefore, control and prevention measures against culicids must be adopted in the study area.

  17. Pond dyes are Culex mosquito oviposition attractants

    Directory of Open Access Journals (Sweden)

    Natali Ortiz Perea

    2017-05-01

    Full Text Available Background British mosquito population distribution, abundance, species composition and potential for mosquito disease transmission are intimately linked to the physical environment. The presence of ponds and water storage can significantly increase the density of particular mosquito species in the garden. Culex pipiens is the mosquito most commonly found in UK gardens and a potential vector of West Nile Virus WNV, although the current risk of transmission is low. However any factors that significantly change the distribution and population of C. pipiens are likely to impact subsequent risk of disease transmission. Pond dyes are used to control algal growth and improve aesthetics of still water reflecting surrounding planting. However, it is well documented that females of some species of mosquito prefer to lay eggs in dark water and/or containers of different colours and we predict that dyed ponds will be attractive to Culex mosquitoes. Methods Black pond dye was used in oviposition choice tests using wild-caught gravid C. pipiens. Larvae from wild-caught C. pipiens were also reared in the pond dye to determine whether it had any impact on survival. An emergence trap caught any adults that emerged from the water. Water butts (80 L were positioned around university glasshouses and woodland and treated with black pond dye or left undyed. Weekly sampling over a six month period through summer and autumn was performed to quantified numbers of larvae and pupae in each treatment and habitat. Results Gravid female Culex mosquitoes preferred to lay eggs in dyed water. This was highly significant in tests conducted under laboratory conditions and in a semi-field choice test. Despite this, survivorship in black dyed water was significantly reduced compared to undyed water. Seasonal analysis of wild larval and pupal numbers in two habitats with and without dye showed no impact of dye but a significant impact of season and habitat. Mosquitoes were more

  18. Fauna de Culicidae da Serra da Cantareira, São Paulo, Brasil Culicidae fauna of Serra da Cantareira, Sao Paulo, Brazil

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    Joyce Montes

    2005-08-01

    estimated using Simpson and Shannon indexes. The correlation between species dominance and climatic factors was estimated by Spearman's coefficient. RESULTS: There were collected 2,219 Culicidae mosquitoes of 11 genera and 21 species. The forest environment showed the highest species richness (Mg=3.64 and the anthropic environment presented the most dominant species (d=0.85. Temperature showed the greatest positive correlation (Rs=0.747; p<0.0001 when analyzing the relationship between climatic factors and number of individuals caught in the study area. CONCLUSIONS: As the Serra da Cantareira State Park is a forest patch inserted in an urban environment, this may have changed the ecological relationships in the Culicidae breeding sites. The absence of Kerteszia subgenus and Culex quinquefasciatus species, in addiction to the presence of Sabethini Tribe specimens and Cx. (Mel. vaxus species indicate that the Serra da Cantareira State Park is a forest section with sylvan features but show some anthropic interference.

  19. Fauna europaea: Diptera - brachycera.

    Science.gov (United States)

    Pape, Thomas; Beuk, Paul; Pont, Adrian Charles; Shatalkin, Anatole I; Ozerov, Andrey L; Woźnica, Andrzej J; Merz, Bernhard; Bystrowski, Cezary; Raper, Chris; Bergström, Christer; Kehlmaier, Christian; Clements, David K; Greathead, David; Kameneva, Elena Petrovna; Nartshuk, Emilia; Petersen, Frederik T; Weber, Gisela; Bächli, Gerhard; Geller-Grimm, Fritz; Van de Weyer, Guy; Tschorsnig, Hans-Peter; de Jong, Herman; van Zuijlen, Jan-Willem; Vaňhara, Jaromír; Roháček, Jindřich; Ziegler, Joachim; Majer, József; Hůrka, Karel; Holston, Kevin; Rognes, Knut; Greve-Jensen, Lita; Munari, Lorenzo; de Meyer, Marc; Pollet, Marc; Speight, Martin C D; Ebejer, Martin John; Martinez, Michel; Carles-Tolrá, Miguel; Földvári, Mihály; Chvála, Milan; Barták, Miroslav; Evenhuis, Neal L; Chandler, Peter J; Cerretti, Pierfilippo; Meier, Rudolf; Rozkosny, Rudolf; Prescher, Sabine; Gaimari, Stephen D; Zatwarnicki, Tadeusz; Zeegers, Theo; Dikow, Torsten; Korneyev, Valery A; Richter, Vera Andreevna; Michelsen, Verner; Tanasijtshuk, Vitali N; Mathis, Wayne N; Hubenov, Zdravko; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera-Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists. Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera-Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger number of small

  20. Abundância de culicídeos em área metropolitana preservada e suas implicações epidemiológicas Culicidae mosquito abundance in a preserved metropolitan area and its epidemiological implications

    Directory of Open Access Journals (Sweden)

    Carmen Beatriz Taipe-Lagos

    2003-06-01

    Full Text Available OBJETIVO: Estudar a fauna de culicídeos adultos em uma área de reserva na periferia urbana para definir as espécies de interesse em saúde pública. MÉTODOS: O estudo foi realizado no Parque Ecológico do Tietê, localizado na periferia urbana da Grande São Paulo, Brasil. Realizaram-se coletas mensais em três locais e horários distintos, com o uso de aspiradores elétricos, armadilhas CDC e de Shannon no período de agosto de 1996 até março de 1998. O tratamento dos dados baseou-se na estimativa de freqüências e abundâncias. RESULTADOS: Coletaram-se 53.496 exemplares, tendo sido reconhecidas 25 espécies ou grupos genéricos. As espécies Ochlerotatus scapularis, Culex quinquefasciatus e Culex declarator foram as mais freqüentes e abundantes. CONCLUSÕES: As espécies mais freqüentes e abundantes têm demonstrado eficiência na transmissão de agentes patogênicos ao homem em outras regiões. Atenção deve ser dada a esses culicídeos, pois o o local investigado, ao lado de um complexo urbano, reúne condições favoráveis à disseminação de doenças por vetores.OBJECTIVE: To study the adult Culicidae fauna in a preserved area in urban outskirts for describing species of public health concern. METHODS: This study was developed in the Tietê Ecological Park located in the outskirt of the city of São Paulo, Brazil. Monthly collections were undertaken in three habitats at different times using electric aspirators and CDC and Shannon traps from August 1996 to March 1998. Data analysis was based on estimates of frequencies and abundance. RESULTS: Twenty-five species or generic groups were identified among 53,496 specimens collected. Ochlerotatus scapularis, Culex quinquefasciatus, and Culex declarator were the most frequent and abundant species. CONCLUSIONS: The most frequent and abundant species have been implicated in disease transmission to man in other regions. Attention must be given to these Culicidae since the study area is

  1. Culex flavivirus and West Nile virus in Culex quinquefasciatus populations in the southeastern United States.

    Science.gov (United States)

    Crockett, Rebekah Kent; Burkhalter, Kristen; Mead, Daniel; Kelly, Rosmarie; Brown, Jeffrey; Varnado, Wendy; Roy, Alma; Horiuchi, Kalanthe; Biggerstaff, Brad J; Miller, Barry; Nasci, Roger

    2012-01-01

    Little is known of the interactions between insect-only flaviviruses and other arboviruses in their mosquito hosts, or the potential public health significance of these associations. The specific aims of this study were to describe the geographic distribution, prevalence, and seasonal infection rates of Culex flavivirus (CxFV) and West Nile virus (WNV) in Culex quinquefasciatus Say in the Southeastern United States, investigate the potential association between CxFV and WNV prevalence in Cx. quinquefasciatus and describe the phylogenetic relationship among CxFV and WNV isolates from the Southeastern United States and around the world. Using ArboNET records, 11 locations were selected across Georgia, Mississippi, and Louisiana that represented a range of WNV human case incidence levels. Cx. quinquefasciatus were trapped weekly throughout the summer of 2009 and pools were screened for flavivirus RNA by reverse transcriptase polymerase chain reaction. Cx. quinquefasciatus from Georgia had significantly higher CxFV infection rates than either Mississippi or Louisiana. CxFV was not detected in Mississippi after July, and no CxFV was detected in Cx. quinquefasciatus in Louisiana. In Georgia, CxFV infection rates were variable between and within counties and over time. WNV infection rates were not significantly different across states or months, and WNV sequences from all three states were identical to each other in the envelope and NS5 gene regions. Phylogenetically, NS5 and E gene sequences from Georgia CxFV isolates clustered with CxFV from Japan, Iowa, and Texas. Multiple CxFV genetic variants were found circulating simultaneously in Georgia. No evidence was found supporting an association between WNV and CxFV infection prevalence in Cx. quinquefasciatus.

  2. Transmission of West Nile virus by Culex quinquefasciatus say infected with Culex Flavivirus Izabal.

    Directory of Open Access Journals (Sweden)

    Rebekah J Kent

    Full Text Available BACKGROUND: The natural history and potential impact of mosquito-specific flaviviruses on the transmission efficiency of West Nile virus (WNV is unknown. The objective of this study was to determine whether or not prior infection with Culex flavivirus (CxFV Izabal altered the vector competence of Cx. quinquefasciatus Say for transmission of a co-circulating strain of West Nile virus (WNV from Guatemala. METHODS AND FINDINGS: CxFV-negative Culex quinquefasciatus and those infected with CxFV Izabal by intrathoracic inoculation were administered WNV-infectious blood meals. Infection, dissemination, and transmission of WNV were measured by plaque titration on Vero cells of individual mosquito bodies, legs, or saliva, respectively, two weeks following WNV exposure. Additional groups of Cx. quinquefasciatus were intrathoracically inoculated with WNV alone or WNV+CxFV Izabal simultaneously, and saliva collected nine days post inoculation. Growth of WNV in Aedes albopictus C6/36 cells or Cx. quinquefasciatus was not inhibited by prior infection with CxFV Izabal. There was no significant difference in the vector competence of Cx. quinquefasciatus for WNV between mosquitoes uninfected or infected with CxFV Izabal across multiple WNV blood meal titers and two colonies of Cx. quinquefasciatus (p>0.05. However, significantly more Cx. quinquefasciatus from Honduras that were co-inoculated simultaneously with both viruses transmitted WNV than those inoculated with WNV alone (p = 0.0014. Co-inoculated mosquitoes that transmitted WNV also contained CxFV in their saliva, whereas mosquitoes inoculated with CxFV alone did not contain virus in their saliva. CONCLUSIONS: In the sequential infection experiments, prior infection with CxFV Izabal had no significant impact on WNV replication, infection, dissemination, or transmission by Cx. quinquefasciatus, however WNV transmission was enhanced in the Honduras colony when mosquitoes were inoculated simultaneously with

  3. ( Euphorbiaceae ) leaf and seed aqueous extracts against Culex ...

    African Journals Online (AJOL)

    In this context, the purpose of the present search was to explore the larvicidal properties of Jatropha curcas L. leaf and seed extracts against Culex pipiens L. The larvicidal activity was evaluated in eight different provenances recently introduced in Tunisia (Tanzania (ARU), Mozambique (MOZ), Surinam (SUR) and Brazil ...

  4. Partial cloning and estimation of the Culex pipiens (SELAX strain ...

    African Journals Online (AJOL)

    The mechanism of resistance towards organophosphate insecticides in Culex complex mosquitoes has been shown to be associated with amplification of the structural esterase gene. The cloned portion of the SELAX strain A2-B2 amplicon was compared to that of the B1 amplicon which had been partially characterized.

  5. Vector competence of Anopheles and Culex mosquitoes for Zika virus

    Directory of Open Access Journals (Sweden)

    Brittany L. Dodson

    2017-03-01

    Full Text Available Zika virus is a newly emergent mosquito-borne flavivirus that has caused recent large outbreaks in the new world, leading to dramatic increases in serious disease pathology including Guillain-Barre syndrome, newborn microcephaly, and infant brain damage. Although Aedes mosquitoes are thought to be the primary mosquito species driving infection, the virus has been isolated from dozens of mosquito species, including Culex and Anopheles species, and we lack a thorough understanding of which mosquito species to target for vector control. We exposed Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes to blood meals supplemented with two Zika virus strains. Mosquito bodies, legs, and saliva were collected five, seven, and 14 days post blood meal and tested for infectious virus by plaque assay. Regardless of titer, virus strain, or timepoint, Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes were refractory to Zika virus infection. We conclude that Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes likely do not contribute significantly to Zika virus transmission to humans. However, future studies should continue to explore the potential for other novel potential vectors to transmit the virus.

  6. Species\\' identification of Anopheles and Culex mosquitoes and its ...

    African Journals Online (AJOL)

    Indoor and outdoor bites' collections of gravid Anopheles and Culex mosquitoes were made with plastic aspirator from residential areas within Jimeta-Yola metropolis for three years (between March and May; August and October 2003 to 2005). They were identified using standard morphological keys and polymerase chain ...

  7. Yeasts Associated with Culex pipiens and Culex theileri Mosquito Larvae and the Effect of Selected Yeast Strains on the Ontogeny of Culex pipiens.

    Science.gov (United States)

    Steyn, A; Roets, F; Botha, A

    2016-04-01

    The success of mosquitoes in nature has been linked to their microbiota and bacteria in particular. Yet, knowledge on their symbioses with yeasts is lacking. To explore possible associations, culturable yeasts were isolated from wild larvae of Culex pipiens and Culex theileri. These yeasts were classified using restriction fragment length polymorphism (RFLP) analyses and identified by sequencing the D1/D2 region of the 26S rRNA gene. Representative strains of Candida, Cryptococcus, Galactomyces, Hannaella, Meyerozyma, Pichia, Rhodosporidium, Rhodotorula, Trichosporon and Wickerhamomyces were isolated. Our results provide, to our knowledge, the first records of the yeast microbiota from wild mosquito larvae and show that they may harbour potential clinically relevant yeast species, including the well-known opportunistic human pathogen Candida albicans. Also, diminished numbers of yeast isolates originating from adults, compared to larvae, support the hypothesis of microbial reduction/elimination during adult emergence and extend it to include yeasts. In addition, strains of Candida albicans, Candida glabrata, Candida pseudolambica, Cryptococcus gattii, Metschnikowia bicuspidata, Saccharomyces cerevisiae and Wickerhamomyces anomalus were tested as sole feed during a 21-day feeding experiment wherein cumulative larval growth, survival and pupation of Cx. pipiens were recorded. Although most yeasts supported larval growth in a similar manner to the positive control S. cerevisiae strain, the different yeast strains impacted differently on Culex pipiens ontogeny. Notably, survival and pupation of larvae were negatively impacted by a representative strain of the primary pathogen C. gattii - signifying some yeasts to be natural antagonists of mosquitoes.

  8. Development of a multiplexed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay to identify common members of the Subgenera Culex (Culex) and Culex (Phenacomyia) in Guatemala.

    Science.gov (United States)

    Kent, Rebekah J; Deus, Stephen; Williams, Martin; Savage, Harry M

    2010-08-01

    Morphological differentiation of mosquitoes in the subgenera Culex (Culex) and Culex (Phenacomyia) in Guatemala is difficult, with reliable identification ensured only through examination of larval skins from individually reared specimens and associated male genitalia. We developed a multiplexed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay to identify common Cx. (Cux.) and Cx. (Phc.). Culex (Cux.) chidesteri, Cx. (Cux.) coronator, Cx. (Cux.) interrogator, Cx. (Cux.) quinquefasciatus, Cx. (Cux.) nigripalpus/Cx. (Cux.) thriambus, and Cx. (Phc.) lactator were identified directly with a multiplexed primer cocktail comprising a conserved forward primer and specific reverse primers targeting ribosomal DNA (rDNA). Culex nigripalpus and Cx. thriambus were differentiated by restriction digest of homologous amplicons. The assay was developed and optimized using well-characterized specimens from Guatemala and the United States and field tested with unknown material from Guatemala. This assay will be a valuable tool for mosquito identification in entomological and arbovirus ecology studies in Guatemala.

  9. Redescripción de la Larva y la Pupa de Toxorhynchites ( Lynchiella guadeloupensis (Diptera: Culicidae Redescription of the larva and pupa of Toxorhynchites ( Lynchiella guadeloupensis (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Lucrecia M. Augier

    2003-07-01

    Full Text Available El objetivo de la presente contribución es redescribir, en forma completa, la quetotaxia de larva y pupa de Toxorhynchites guadeloupensis (Dyar & Knab. Además se describe por primera vez el aparato bucal de la larva. El material estudiado procede de la provincia de Tucumán en el noroeste argentino.The objetive of the present contribution is to redescribe the quetotaxia of the larva and the pupa of Toxorhynchites guadeloupensis (Dyar & Knab. The larval mouthpart is described for the first time. The material examined is from Tucumán province in the Argentina northwestern.

  10. Observações sobre os mosquitos Culex da cidade de São Paulo, Brasil Observations on Culex mosquitoes of S. Paulo City, Brazil

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    Oswaldo Paulo Forattini

    1973-12-01

    Full Text Available São apresentados os resultados obtidos na coleta de mosquitos do gênero Culex na área urbana da cidade de São Paulo, Brasil. Foram empregadas armadilhas luminosas automáticas tipo "New Jersey 50". Os resultados revelaram a presença de outras populações representadas principalmente por Culex chidesteri, C. dolosus e C. bidens as quais, em conjunto, chegaram algumas vezes a sobrepujar a de Culex pipiens fatigans. O maior rendimento foi obtido em áreas com abastecimento de água mas sem rede de esgotos. As coletas intradomiciliares revelaram franca predominância de C. pipiens fatigans.With the use of New Jersey-50 light traps, a survey of Culex mosquitoes was made in the urban área of São Paulo City, Brazil. Beside Culex pipiens fatigans several other species were found, mainly represented by Culex chidesteri, C. dolosus and C. bidens. The combined incidence of these three populations follows nearly the fatigans one and frequently exceeding it. The most high levels of density were found at areas with water treatment but without sewage disposal. Domiciliary collections showed great Culex pipiens fatigans predominancy.

  11. Detection of Orthobunyavirus in mosquitoes collected in Argentina.

    Science.gov (United States)

    Tauro, L B; Batallan, G P; Rivarola, M E; Visintin, A; Berrón, C I; Sousa, E C; Diaz, L A; Almiron, W R; Nunes, M R; Contigiani, M S

    2015-09-01

    Bunyamwera virus (BUNV) (Bunyaviridae, genus Orthobunyavirus, serogroup Bunyamwera) is considered an emerging pathogen for humans and animals in American countries. The CbaAr-426 strain of BUNV was recovered from mosquitoes Ochlerotatus albifasciatus (Diptera: Culicidae) collected in Córdoba province (Argentina), where serological studies detected high seroprevalences in humans and animals. Molecular detection of Orthobunyavirus was performed in mosquitoes collected in Córdoba province. Seventeen mosquito pools of Oc. albifasciatus, Ochlerotatus scapularis and Culex quinquefasciatus (Diptera: Culicidae) showed positive results; four of these positive pools, all of Oc. scapularis, were sequenced. All amplicons grouped with BUNV in the Bunyamwera serogroup. The findings highlight the circulation of BUNV in Córdoba province and represent the first report of BUNV-infected Oc. scapularis mosquitoes in Argentina. © 2015 The Royal Entomological Society.

  12. [PCR-RFLP and sequencing studies of malaria vectors (Diptera, Culicidae, Anopheles) in Kyrgyzstan].

    Science.gov (United States)

    Goriacheva, I I; Zvantsov, A B; Gordeev, M I; Bezzhonova, O V; Usenbaev, N T; Ezhov, M N

    2011-01-01

    The results of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis, obtained after treatment of PCR-products with restriction endonuclease CfoI, could identify two members of the Anopheles maculipennis complex: An. maculipennis and An. artemievi. Treatment of amplification products with restriction endonuclease BsuI gave rise to fragment lengths of 192 and 218 bp, characteristic of An. artemievi, in the populations of the Talas (settlement of Kizil-Adyr, Kara-Bura District), Dzhelalabad (towns of Tashkumyr and Kara-Kul), and Osh (town of Gulcha, Alai District; village of Langar, Kara-Suisky District) Regions. After treatment of PCR-products with restriction endonuclease BstACI, fragment lengths of 292 and 150 bp, characteristic of An. messeae, were obtained for the mosquitoes of Issyk-Kul (town of Balykchi) and Naryn (settlement of Kochkorka, Kochkor District) Regions. To identify the molecular forms of An. superpictus, the investigators sequenced the amplification products obtained by PCR with 5.8S and 28S rRNA gene-specific primers. Analysis of the primary structure of the second internal transcribed spacer, by using the international databases, has indicated that molecular form X is prevalent in the study districts of Kyrgyzstan. The COI-COII region of the mitochondrial genome of the vector also underwent PCR-RFLP analysis. Three new haplotypes with restriction patterns of about 540, 420, 200, 150, 140 bp, about 540, 360, 280, 150, 140 bp, and about 580, 540, and 150, 140 bp have been identified along with the previously described haplotype X characterized by restriction products of 540, 420, 260, 150, and 140 bp in length.

  13. Diterpenos de Copaifera reticulata Ducke com atividade larvicida contra Aedes aegypti (L. (Diptera, Culicidae

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    Regina Geris

    2008-02-01

    Full Text Available The objective of this study was to evaluate the larvicidal activity of diterpenoids obtained from the oil-resin of Copaifera reticulata against Aedes aegypti larvae, the principal vector of dengue and urban yellow fever. Four diterpenes were obtained from oil-resin extraction with organic solvents and subsequent chromatographic and spectroscopic procedures allowed to isolation and identification of these compounds as 3-b-acetoxylabdan-8(17-13-dien-15-oic acid (1, alepterolic acid (2, 3-b-hidroxylabdan-8(17-en-15-oic acid (3, and ent-agatic acid (4. Each compound was previously dissolved in dimethylsulphoxide, and distilled water was added to obtain the desired concentrations. Twenty larvae of third instars were placed into plastic beckers, containing the solution test (25 mL, in a five repetitions scheme, and their mortality, indicated by torpor and darkening of the cephalic capsule, was recorded after 48h. Probit analyses were used to determine lethal concentrations (LC50 and LC90 and their respective 95% confidence intervals. This study showed that only diterpenoids 1 and 2 exhibited larvicidal properties with LC50 of 0.8 ppm and 87.3 ppm, respectively, revealing the former as the most toxic compound against third instars of Ae. aegypti. Therefore, this compound seems to be an interesting source for new metabolite to be exploited.O objetivo deste trabalho foi avaliar a atividade larvicida de diterpenos isolados do óleo-resina de Copaifera reticulata sobre Aedes aegypti, principal vetor de dengue e febre amarela urbana. Quatro diterpenóides foram obtidos a partir da extração do óleo-resina com solventes orgânicos e, subseqüentes procedimentos cromatográficos e espectroscópicos permitiram o isolamento e a identificação desses compostos como ácido 3-b-acetoxylabdan-8(17-13-dien-15-óico (1, ácido alepterólico (2, ácido 3-b-hidroxylabdan-8(17-en-15-óico (3 e ácido ent-agático (4. Cada um desses compostos foi previamente solubilizado em dimetilsulfóxido, acrescentando-se água, até se obterem as concentrações desejadas. Em cada bioensaio foram utilizadas 20 larvas de 3° estádio de Ae. aegypti colocadas em 25 mL da solução-teste. Foram feitas cinco repetições, e a mortalidade avaliada 48 h após a exposição, indicada pela ausência de movimentos e escurecimento da cápsula cefálica. Os dados obtidos da mortalidade x concentração (ppm foram analisados, em gráfico de Probit para avaliar as concentrações letais (CL50 e CL90. Este estudo revelou que os diterpenóides 1 e 2 mostraram atividade larvicida com CL50 de 0,8 e 87,3 ppm, respectivamente, sendo o diterpeno 1 o composto mais promissor a ser usado como larvicida para o controle de Ae. aegypti.

  14. Enzyme polymorphism of the malaria vector, An. balabacensis (Diptera: Culicidae) revisited--why sample natural populations?

    Science.gov (United States)

    Hii, J L; Chew, M; Vun, Y S; Nasir, M; Chang, M S

    1988-12-01

    Two separate observations from recent electrophoretic studies of the systematics and population genetics of laboratory-reared populations which had a long history of colonization in various laboratories, were found to be inconsistent with the present study which used wild-caught populations from East Malaysia. Reanalysis of the two data sets generally indicated a low amount of genetic variation in laboratory colonies. The latter is characterized by higher frequency of monomorphic loci, low average heterozygosity values and, in one extreme case, no variability at two loci. However, natural populations of An. balabacensis and An. leucosphyrus showed more protein variability by the use of polyacrylamide gel electrophoresis. Since laboratory-maintained mosquitoes are genetically and phenotypically different from those in the field, results of laboratory studies on the systematics and population genetics of Anopheles species complexes may be biased.

  15. Nepenthes ampullaria (Nepenthaceae) Pitchers Are Unattractive to Gravid Aedes aegypti and Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Chou, Lee Yiung; Dykes, Gary A; Wilson, Robyn F; Clarke, Charles M

    2016-02-01

    Nepenthes pitcher plants are colonized by a variety of specialized arthropods. As Aedes mosquitoes are container breeders, Nepenthes pitchers are a potential candidate oviposition site for vector species, such as Aedes aegypti (L.) and Aedes albopictus (Skuse). However, Aedes spp. are not commonly encountered in Nepenthes pitchers, and the environment inside the pitchers of some species is lethal to them. One exception is Nepenthes ampullaria Jack, whose pitchers are known to be colonized by Ae. albopictus on very rare occasions. Given that Ae. albopictus larvae can survive in N. ampullaria pitcher fluids, we sought to determine why pitcher colonization is rare, testing the hypothesis that gravid Aedes mosquitoes are deterred from ovipositing into container habitats that have similar characteristics to N. ampullaria pitchers. Using plastic ovitraps of different sizes, colors, and with different types of fluids (based on the characteristics of N. ampullaria pitchers), we compared oviposition rates by Aedes mosquitoes in urban and rural areas within the geographical range of N. ampullaria near Kuala Lumpur, Malaysia. Ovitraps that were black and large (>250-ml capacity) accumulated significantly more eggs than ovitraps that were smaller, or green in color. In terms of size and color, small, green ovitraps are analogous to N. ampullaria pitchers, indicating that these pitchers are not particularly attractive to gravid Ae. albopictus. Although Aedes spp. are capable of colonizing N. ampullaria pitchers, the pitchers are relatively unattractive to gravid females and do not represent a significant habitat for larvae of dengue vectors at present. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Bio-Pesticides: New Tool for the Control of Aedes (Stegomyia albopictus (Culicidae: Diptera in Pakistan

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    Hazrat Bilal

    2017-06-01

    Full Text Available Background: Application of plant extracts as mosquito control strategy was practiced from centuries. These are easily available, non-toxic, biodegradable and exhibit broad-spectrum target specific activities against larval stages of mosquitoes.Method: Different potential parts of locally grown plants, seeds of nutmeg (Myristica fragrans, peel of musambi (Citrus sinensis, leaves of babuna (Matricaria chamomilla, mint (Mentha spicata and ginger rhizome (Zingiber officinale selected and evaluated for their larvicidal properties against Aedes (Stegomyis albopictus. Oils were ex­tracted through steam distillation process and extracts were evaluated as per WHO 2005 guidelines for testing of insecticides against larvae of mosquitoes.Result: Among the five plant extracts, C. sinensis had the lowest LC50 (400.81ppm while M. fragrans had the high­est LC50 value (710.30ppm respectively after 24h of exposure. In terms of % age mortality, a series of con­centra­tions (300–800ppm gave high % mortality in case of C. sinensis while M. fragrans gave low % age mortality.Conclusion: All the five plant species have larvicidal effects to certain extant and C. sinensis had great potential. Further small-scale field trials with the extracts of the most promising one (C. sinensis shall be conducted to deter­mine operational feasibility.    

  17. Potential Distribution of Two Species in the Medically Important Anopheles minimus Complex (Diptera: Culicidae)

    Science.gov (United States)

    2008-09-01

    and the DDT house- spray malaria control program may have eliminated this taxon from some areas. Jambulingam et al. (2005) reported that An. minimus...Shackelford, and S. Sarkar. 2007. Malaria in Africa: vector speciesÕ niche models and relative risk maps. PloS ONE 2: e824. (doi:10.1371

  18. Comparative effectiveness of monomolecular surface film on Aedes aegypti (L. and Anopheles minimus (Theobald (Diptera: Culicidae

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    Chutipong Sukkanon

    2016-11-01

    Full Text Available Silicone-based surfactants have become of interest for mosquito control in Thailand. When this non-ionic surfactant is applied in mosquito habitats, a monomolecular film (MMF forms on the water surface and disrupts the ability of larvae and pupae to breathe. In this study, a laboratory bioassay was conducted to determine the mosquito control potential of MMF against Aedes aegypti (L. and Anopheles minimus (Theobald, and to compare its efficacy with other larvicides consisting of temephos (an organophosphate, Bacillus thuringiensis israelensis (Bti and pyriproxyfen (an insect growth regulator. It was determined that the percentage mortality of Ae. aegypti and An. minimus treated with MMF at a recommended dosage of 1 mL/m2 was significantly greater in pupae (99.2% and 100%, respectively than old stage larvae (L3–L4, age 46 d; 70.8% and 97.5%, respectively and young stage larvae (L1–L2, age 1–2 d; 8.3% and 58.0%, respectively. Small larvae and prolonged stage transformations indicated MMF growth inhibition activity. MMF also displayed oviposition deterrence behavior and caused female mosquitoes to drown during egg laying. In comparison, temephos and Bti were highly effective in larval control while pyriproxyfen and MMF provided excellent control effects against the pupal stage. Based on the results, MMF showed promise as an alternative larvicide for mosquito control in Thailand. Further studies on the environmental effects of MMF are needed.

  19. [Taxonomic composition of metagenomic community in the larval gut of mosquito Anopheles sinensis (Diptera: Culicidae)].

    Science.gov (United States)

    Nan, Chun-Yan; Ma, Ya-Jun; Xu, Jian-Nong; Liang, Jian

    2013-04-01

    To investigate the bacteria diversity in larval gut of field-collected Anopheles sinensis. The 16S rDNA V4 region of An. sinensis larvae collected from paddy on Jiading District of Shanghai (L1/L2) and small seeping water on Wenchang City of Hainan (AS) was sequenced by high-throughput pyrosequencing. Using Qiime and Mothur softwares, the number of sequences and operational taxonomic units (OTUs) for each sample was sorted and calculated, the species abundance and distribution, Alpha diversity index and difference times of species abundance among samples were analyzed. The number of sequences and OTUs for each sample were 253 724/3 930 (L1), 225 203/4 312 (L2) and 73 990/2 380 (AS). The rarefaction curves showed that adequate sampling was achieved. The number of OTUs was close to actual situation. The value of richness index was 5 942.61/6 534.88 (L1), 6 328.17/7 235.89 (L2) and 4228.66/5 651.20 (AS); diversity index was 4.63/0.03 (L1), 5.10/0.02 (L2) and 0.14/3.94 (AS). The dominant species of An. sinensis larvae gut microbiota all belonged to the phylum Proteobacteria, with a percentage of 87% (AS) and 90% (L). In addition, the dominant phyla among them were Firmicutes, Bacteroidetes and Actinobacteria. The comparison of bacterial abundance between L and AS showed that there were 18 phyla with significant difference, except the Proteobacteria and Deinococcus-Thermus; only 9 phyla were different significantly between L1 and L2. Evenness and richness of bacteria flora in the An. sinensis larvae gut collected from paddy and small seeping waters were obtained.

  20. The role of midgut symbiotic bacteria in resistance of Anopheles stephensi (Diptera: Culicidae) to organophosphate insecticides.

    Science.gov (United States)

    Soltani, Aboozar; Vatandoost, Hassan; Oshaghi, Mohammad Ali; Enayati, Ahmad Ali; Chavshin, Ali Reza

    2017-09-01

    In the current study, the effects of the presence of symbiotic bacteria on the activity of the enzymes involved in An. stephensi resistance to temephos are evaluated for the first time. Four different strains (I. susceptible strain, II. resistant strain, III. resistant strain + antibiotic, and IV. resistant strain + bacteria) were considered in order to determine the possible effects of the symbiotic bacteria on their hosts' resistance to temephos. The median values of all enzymes of susceptible strain were compared with those of other resistant strains. The results of this study indicated a direct relationship between the presence of bacteria in the symbiotic organs of An. stephensi and resistance to temephos. The profile of enzymatic activities in the resistant strain changed to a susceptible status after adding antibiotic. The resistance of An. stephensi to temephos could be completely broken artificially by removing their bacterial symbionts in a resistant population.

  1. Effectiveness of synthetic versus natural human volatiles as attractants for Anopheles gambiae (Diptera: Culicidae) sensu stricto

    NARCIS (Netherlands)

    Smallegange, R.C.; Knols, B.G.J.; Takken, W.

    2010-01-01

    Females of the African malaria vector, Anopheles gambiae Giles sensu stricto, use human volatiles to find their blood-host. Previous work has shown that ammonia, lactic acid, and aliphatic carboxylic acids significantly affect host orientation and attraction of this species, In the current study,

  2. Modelling the spatial distribution of the nuisance mosquito species Anopheles plumbeus (Diptera Culicidae) in the Netherlands

    NARCIS (Netherlands)

    Ibañez-Justicia, Adolfo; Cianci, Daniela

    2015-01-01

    BACKGROUND: Landscape modifications, urbanization or changes of use of rural-agricultural areas can create more favourable conditions for certain mosquito species and therefore indirectly cause nuisance problems for humans. This could potentially result in mosquito-borne disease outbreaks when the

  3. Chemical Constituents and Combined Larvicidal Effects of Selected Essential Oils against Anopheles cracens (Diptera: Culicidae

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    Jitrawadee Intirach

    2012-01-01

    Full Text Available A preliminary study on larvicidal activity against laboratory-colonized Anopheles cracens mosquitos revealed that five of ten plant oils at concentration of 100 ppm showed 95–100% larval mortality. The essential oils of five plants, including Piper sarmentosum, Foeniculum vulgare, Curcuma longa, Myristica fragrans, and Zanthoxylum piperitum, were then selected for chemical analysis, dose-response larvicidal experiments, and combination-based bioassays. Chemical compositions analyzed by gas chromatography coupled to mass spectrometry demonstrated that the main component in the oil derived from P. sarmentosum, F. vulgare, C. longa, M. fragrans, and Z. piperitum was croweacin (71.01%, anethole (63.00%, ar-turmerone (30.19%, safrole (46.60%, and 1,8-cineole (21.27%, respectively. For larvicidal bioassay, all five essential oils exerted promising efficacy in a dose-dependent manner and different performances on A. cracens after 24 hours of exposure. The strongest larvicidal potential was established from P. sarmentosum, followed by F. vulgare, C. longa, M. fragrans, and Z. piperitum, with LC50 values of 16.03, 32.77, 33.61, 40.00, and 63.17 ppm, respectively. Binary mixtures between P. sarmentosum, the most effective oil, and the others at the highest ratio were proved to be highly efficacious with a cotoxicity coefficient value greater than 100, indicating synergistic activity. Results of mixed formulations of different essential oils generating synergistic effects may prove helpful in developing effective, economical, and ecofriendly larvicides, as favorable alternatives for mosquito management.

  4. Anopheles plumbeus (Diptera: Culicidae in Europe: a mere nuisance mosquito or potential malaria vector?

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    Schaffner Francis

    2012-11-01

    Full Text Available Abstract Background Anopheles plumbeus has been recognized as a minor vector for human malaria in Europe since the beginning of the 20th century. In recent years this tree hole breeding mosquito species appears to have exploited novel breeding sites, including large and organically rich man-made containers, with consequently larger mosquito populations in close vicinity to humans. This lead to investigate whether current populations of An. plumbeus would be able to efficiently transmit Plasmodium falciparum, the parasite responsible for the most deadly form of malaria. Methods Anopheles plumbeus immatures were collected from a liquid manure pit in Switzerland and transferred as adults to the CEPIA (Institut Pasteur, France where they were fed on P. falciparum gametocytes produced in vitro. Anopheles gambiae mosquitoes served as controls. Development of P. falciparum in both mosquito species was followed by microscopical detection of oocysts on mosquito midguts and by sporozoite detection in the head/thorax by PCR and microscopy. Results A total of 293 wild An. plumbeus females from four independent collections successfully fed through a membrane on blood containing P. falciparum gametocytes. Oocysts were observed in mosquito midguts and P. falciparum DNA was detected in head-thorax samples in all four experiments, demonstrating, on a large mosquito sample, that An. plumbeus is indeed receptive to P. falciparum NF54 and able to produce sporozoites. Importantly, the proportion of sporozoites-infected An. plumbeus was almost similar to that of An. gambiae (31 to 88% An. plumbeus versus 67 to 97% An. gambiae. However, the number of sporozoites produced was significantly lower in infected An. plumbeus. Conclusion The results show that a sample of field-caught An. plumbeus has a moderate to high receptivity towards P. falciparum. Considering the increased mobility of humans between Europe and malaria endemic countries and changes in environment and climate, these data strongly suggest that An. plumbeus could act as a vector for malaria and thus significantly contribute to increasing the malaria transmission risk in Central-Western Europe. In locations showing high vulnerability to the presence of gametocyte carriers, the risk of transmission of malaria by An. plumbeus should be considered.

  5. Wolbachia and dengue virus infection in the mosquito Aedes fluviatilis (Diptera: Culicidae.

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    Jéssica Barreto Lopes Silva

    Full Text Available Dengue represents a serious threat to human health, with billions of people living at risk of the disease. Wolbachia pipientis is a bacterial endosymbiont common to many insect species. Wolbachia transinfections in mosquito disease vectors have great value for disease control given the bacterium's ability to spread into wild mosquito populations, and to interfere with infections of pathogens, such as dengue virus. Aedes fluviatilis is a mosquito with a widespread distribution in Latin America, but its status as a dengue vector has not been clarified. Ae. fluviatilis is also naturally infected by the wFlu Wolbachia strain, which has been demonstrated to enhance infection with the avian malarial parasite Plasmodium gallinaceum. We performed experimental infections of Ae. fluviatilis with DENV-2 and DENV-3 isolates from Brazil via injection or oral feeding to provide insight into its competence for the virus. We also examined the effect of the native Wolbachia infection on the virus using a mosquito line where the wFlu infection had been cleared by antibiotic treatment. Through RT-qPCR, we observed that Ae. fluviatilis could become infected with both viruses via either method of infection, although at a lower rate than Aedes aegypti, the primary dengue vector. We then detected DENV-2 and DENV-3 in the saliva of injected mosquitoes, and observed that injection of DENV-3-infected saliva produced subsequent infections in naïve Ae. aegypti. However, across our data we observed no difference in prevalence of infection and viral load between Wolbachia-infected and -uninfected mosquitoes, suggesting that there is no effect of wFlu on dengue virus. Our results highlight that Ae. fluviatilis could potentially serve as a dengue vector under the right circumstances, although further testing is required to determine if this occurs in the field.

  6. Variation in the hatching response of Ochlerotatus albifasciatus egg batches (Diptera: Culicidae in temperate Argentina

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    Raúl Ernesto Campos

    2006-02-01

    Full Text Available Egg hatching of winter-collected Ochlerotatus albifasciatus was studied for six months. Batches of eggs were divided into two groups, one of them was stored in the laboratory at 23°C and 12:12 photoperiod, and the other in the field under dead leaves. Every month, from July to December, eggs from the two groups were flooded under both laboratory and field conditions. Unhatched eggs were returned to the original condition and flooded two more times separated by ten-day intervals. Results show that egg diapause is expressed in different intensities, not only on eggs exposed to different conditions but also in those exposed to the same condition, even when they were laid by the same female. Successive inundations yielded incomplete hatches of eggs, and favored the hatching response in the next flooding. Low environmental temperatures before and during the flooding depressed hatching response. This shows that eggs need a warm period before flooding as well as warm temperatures during flooding, to hatch. As drought period was longer hatching response increased, but this was also accompanied by warmer environmental conditions. The experiment performed in laboratory did not show that increment. Field studies showed that a layer of dead leaves protected eggs from extreme temperatures.

  7. Photoperiodic Diapause and the Establishment of Aedes albopictus (Diptera: Culicidae) in North America.

    Science.gov (United States)

    Armbruster, Peter A

    2016-09-01

    The invasion and range expansion of Aedes albopictus (Skuse) in North America represents an outstanding opportunity to study processes of invasion, range expansion, and climatic adaptation. Furthermore, knowledge obtained from such research is relevant to developing novel strategies to control this important vector species. Substantial evidence indicates that the photoperiodic diapause response is an important adaptation to climatic variation across the range of Ae. albopictus in North America. Photoperiodic diapause is a key determinant of abundance in both space and time, and the timing of entry into and exit out of diapause strongly affects seasonal population dynamics and thus the potential for arbovirus transmission. Emerging genomic technologies are making it possible to develop high-resolution, genome-wide genetic markers that can be used for genetic mapping of traits relevant to disease transmission and phylogeographic studies to elucidate invasion history. Recent work using next-generation sequencing technologies (e.g., RNA-seq), combined with physiological experiments, has provided extensive insight into the transcriptional basis of the diapause response in Ae. albopictus Applying this knowledge to identify novel targets for vector control represents an important future challenge. Finally, recent studies have begun to identify traits other than diapause that are affected by photoperiodism. Extending this work to identify additional traits influenced by photoperiod should produce important insights into the seasonal biology of Ae. albopictus. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Evidence for Arbovirus Dissemination Conduits from the Mosquito (Diptera: Culicidae) Midgut

    National Research Council Canada - National Science Library

    Romoser, William

    2004-01-01

    .... Experiments using Venezuelan equine encephalitis viral replicon particles, which express the green fluorescent protein gene in cells, indicate the operation of tissue conduits, possibly involving...

  9. Genetic variability in geographical populations of Aedes aegypti (Diptera, Culicidae in Brazil elucidated by molecular markers

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    Karina dos Santos Paduan

    2006-01-01

    Full Text Available The tropical mosquito, Aedes aegypti is the most important domestic vector of urban yellow fever and dengue. Genetic population studies on this vector are important because they may lead to new tools for surveillance. An analysis of genetic structure was conducted among populations of A. aegypti from 11 localities in four demographic regions within six Brazilian federal states. Markers included 21 random amplified polymorphic DNA (RAPD loci. RAPD markers were detected among populations and cluster analysis revealed two main groups. We found high genetic polymorphism (H S = 0.224 and high levels of genetic differentiation between populations from different states (G ST = 0.430, as well as in populations from cities in the same state (G ST = 0.410. These results indicate significant differentiation in A. aegypti populations in Brazil. Regression analyses of geographic distances and pairwise F ST values estimated from RAPD markers showed that there is a correlation between genetic structure and geographic localization.

  10. Susceptibility of larval Aedes aegypti and Aedes albopictus (Diptera: Culicidae) to dengue virus.

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    Bara, J J; Clark, T M; Remold, S K

    2013-01-01

    Mosquitoes vertically transmit many arthropod borne viruses, and as a consequence arboviruses are often present within the larval environment. We tested the hypothesis that Aedes aegypti (L.) and Aedes albopictus (Skuse) larvae were susceptible to dengue virus through two infection methods: exposure to dengue in the larval growth environment via viral supernatant, and exposure to infected tissue culture along with viral supernatant. In addition to investigating for the first time the susceptibility of larval Ae. albopictus to dengue virus, we analyzed the infection rate and viral titer of infected pools of Ae. aegypti when exposed to multiple serotypes of dengue. We found that both Ae. aegypti and Ae. albopictus larvae were susceptible to the three dengue virus serotypes to which they were exposed regardless of the exposure method and that there were significant differences between the serotypes in infection titer and infection rate. The finding that larval Ae. aegypti and Ae. albopictus are susceptible to dengue indicates that dengue might be able to spread among larvae within the larval habitat potentially contributing to the persistence of dengue in the environment.

  11. Susceptibility of Aedes albopictus Skuse (Diptera: Culicidae) to permethrin in Kuala Lumpur, Malaysia

    National Research Council Canada - National Science Library

    Othman Wan-Norafikah; Wasi Ahmad Nazni; Han Lim Lee; Pawanchee Zainol-Ariffin; Mohd Sofian-Azirun

    2013-01-01

    ...: The susceptibility status of laboratory susceptible strain, permethrin-selected strain, and four field strains of Aedes albopictus collected from Kuala Lumpur were determined using three standard...

  12. Larval environmental temperature and the susceptibility of Aedes albopictus Skuse (Diptera: Culicidae) to Chikungunya virus.

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    Westbrook, Catherine J; Reiskind, Michael H; Pesko, Kendra N; Greene, Krystle E; Lounibos, L Philip

    2010-04-01

    A key feature in the recent widespread epidemic of the mosquito-borne alphavirus chikungunya virus (CHIKV) was the important role of Aedes albopictus, formerly regarded as a secondary vector, compared to the presumed primary vector Aedes aegypti. Ae. albopictus, a container-inhabiting mosquito, is an invasive species that occurs over a wide geographic range spanning tropical and temperate latitudes. In this study we examine the effects of a broad range of larval rearing temperatures on CHIKV infection, dissemination, and viral titer in Florida F(1) Ae. albopictus. Adults from larvae reared at 18 degrees C, 24 degrees C, and 32 degrees C differed significantly in size, development time, and CHIKV infection rate. Adult females with the largest body size were produced from the coolest temperature, took the longest to mature, and six times more likely to be infected with CHIKV than females reared at 32 degrees C. There was also a significant effect of rearing temperature on viral dissemination, resulting in an increase in population dissemination at the coolest temperature. This study indicates that climate factors, such as temperature, experienced at the larval stage, can influence the competence of adult females to vector arboviruses.

  13. Invasion of Aedes albopictus (Diptera: Culicidae) into central Africa: what consequences for emerging diseases?

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    Ngoagouni, Carine; Kamgang, Basile; Nakouné, Emmanuel; Paupy, Chistophe; Kazanji, Mirdad

    2015-03-31

    Aedes albopictus, a mosquito native to Asia, has invaded all five continents during the past three decades. It was reported in central Africa in the 2000s, first in Cameroon, and, since then, has colonised almost all countries of the region. The species, originally considered a secondary vector of dengue viruses, has been showed to play a major role in transmission of chikungunya virus in numerous countries, including in the central African region. We review the current spread of Ae. albopictus in central Africa, its larval ecology and its impact on indigenous species such as Ae. aegypti. We explore the potential of Ae. albopictus to affect the epidemiology of emerging or re-emerging arboviruses and discuss the conventional means for its control, while emphasizing the importance of data on its susceptibility to insecticides to cope with potential outbreaks.

  14. Aedes albopictus (Diptera: Culicidae) and Mosquito-Borne Viruses in the United States.

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    Vanlandingham, Dana L; Higgs, Stephen; Huang, Yan-Jang S

    2016-09-01

    The Asian tiger mosquito Aedes albopictus (Skuse), is a highly invasive species that continues to expand its geographic distribution both in the United States and in countries on other continents. Studies have demonstrated its susceptibility to infection with at least 32 viruses, including 13 that are present in the United States. Despite this susceptibility, its role as a significant competent vector in natural transmission cycles of arboviruses, has been limited. However, with the recent introductions of chikungunya and Zika viruses into the Americas, for which Ae. albopictus is a recognized vector, it is possible that the species may contribute to the transmission of these viruses to humans and perhaps other susceptible vertebrates. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Frequency of pyrethroid resistance in Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in Thailand.

    Science.gov (United States)

    Chuaycharoensuk, Thipwara; Juntarajumnong, Waraporn; Boonyuan, Wasana; Bangs, Michael J; Akratanakul, Pongthep; Thammapalo, Suwit; Jirakanjanakit, Nuananong; Tanasinchayakul, Somchai; Chareonviriyaphap, Theeraphap

    2011-06-01

    Thirty-two Aedes aegypti populations collected throughout Thailand and five populations of Aedes albopictus from southern Thailand were subjected to standard WHO contact bioassays to assess susceptibility to three commonly used synthetic pyrethroids: permethrin, deltamethrin, and lambda-cyhalothrin. A wide degree of physiological response to permethrin was detected in Ae. aegypti, ranging from 56.5% survival (Lampang, northern Thailand) to only 4% (Kalasin in northeastern and Phuket in southern Thailand). All 32 populations of Ae. aegypti were found to have evidence of incipient resistance (62.5%) or levels of survival deemed resistant (37.5%) to permethrin. Four populations of Ae. albopictus were found with incipient resistance (97 - 80% mortality) and one with resistance (susceptible (> 98% mortality) to deltamethrin, with incipient resistance (observed 97-82% mortality) in other localities. In contrast, all populations of Ae. aegypti were completely susceptible (100% mortality) to the recommended operational dosage of lambda-cyhalothrin. All five populations of Ae. albopictus were found completely susceptible to both deltamethrin and lambda-cyhalothrin. Evidence of defined incipient or resistance to synthetic pyrethroids mandates appropriate response and countermeasures to mitigate further development and spread of resistance. In light of these findings, we conclude that routine and comprehensive susceptibility monitoring of dengue mosquito vectors to synthetic pyrethroids should be a required component of resistance management policies and disease control activities. © 2011 The Society for Vector Ecology.

  16. Can pesticides and larval competition alter susceptibility of Aedes mosquitoes (Diptera: Culicidae) to arbovirus infection?

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    Muturi, Ephantus J; Costanzo, Katie; Kesavaraju, Banugopan; Alto, Barry W

    2011-03-01

    Density-dependent processes such as larval competition may be important regulatory factors among some mosquito species. The application of pesticides used for control may alter these density-dependent interactions with consequences for the number of survivors and associated sublethal and chronic effects on these individuals. We examined how intraspecific competition among larvae and low concentrations of malathion alter Aedes aegypti L. and Aedes albopictus Skuse adult life history traits and competence for arboviruses using Sindbis virus as a model system. Larvae were reared at densities of 150 and 300 larvae per container and in the absence or presence of 0.04 parts per million of malathion, before surviving females were exposed to an infectious blood meal containing 10(5) plaque-forming units/ml Sindbis virus. For both species, competition and the presence of malathion reduced survival to adulthood. The presence of malathion eliminated the negative effects of competition that resulted in lengthened development time and smaller-sized adults. For Ae. aegypti, but not Ae. albopictus, high competition conditions and the presence of malathion independently and not interactively led to an increase in virus dissemination from the midgut. Our results suggest that larval competition and chemical contaminants may influence disease transmission directly by altering adult mosquito fitness and indirectly by altering vector interactions with arboviruses.

  17. Intra-instar larval cannibalism in Anopheles gambiae (s.s. and Anopheles stephensi (Diptera: Culicidae

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    Daniele Porretta

    2016-11-01

    Full Text Available Abstract Background Cannibalism has been observed in a wide range of animal taxa and its importance in persistence and stability of populations has been documented. In anopheline malaria vectors the inter-instar cannibalism between fourth- and first-instar larvae (L4-L1 has been shown in several species, while intra-instar cannibalism remains poorly investigated. In this study we tested the occurrence of intra-instar cannibalism within larvae of second-, third- and fourth-instar (L2, L3 and L4 of Anopheles gambiae (s.s. and An. stephensi. Experiments were set up under laboratory conditions and the effects of larval density, duration of the contact period among larvae and the presence of an older larva (i.e. a potential cannibal of bigger size on cannibalism rate were analysed. Cannibalism was assessed by computing the number of missing larvae after 24 and 48 h from the beginning of the experiments and further documented by records with a GoPro videocamera. Results Intra-instar cannibalism was observed in all larval instars of both species with higher frequency in An. gambiae (s.s. than in An. stephensi. In both species the total number of cannibalistic events increased from 0–24 to 0–48 h. The density affected the cannibalism rate, but its effect was related to the larval instar and to the presence of older larvae. Interestingly, the lower cannibalism rate between L4 larvae was observed at the highest density and the cannibalism rate between L3 larvae decreased when one L4 was added. Conclusions The present study provides experimental evidence of intra-instar cannibalism in the malaria vectors An. gambiae (s.s. and An. stephensi and highlights the possible occurrence of complex interactions between all larval instars potentially present in the breeding sites. We hypothesize that the high density and the presence of a potential cannibal of bigger size could affect the readiness to attack conspecifics, resulting into low risk larval behavior and lower cannibalism rate. The understanding of cannibalistic behavior and the factors affecting it is of utmost importance for malaria vectors, as nutrition during larval development can strongly affect the fitness of adult female mosquitoes and ultimately their vector ability.

  18. Intra-instar larval cannibalism in Anopheles gambiae (s.s.) and Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Porretta, Daniele; Mastrantonio, Valentina; Crasta,