Canavoso,Lilián E; Stariolo,Raúl; Rubiolo,Edilberto R
The metabolism of lipids and carbohydrates related to flight activity in Panstrongylus megistus was investigated. Insects were subjected to different times of flight under laboratory conditions and changes in total lipids, lipophorin density and carbohydrates were followed in the hemolymph. Lipids and glycogen were also assayed in fat body and flight muscle. In resting insects, hemolymph lipids averaged 3.4 mg/ml and significantly increased after 45 min of flight (8.8 mg/ml, P < 0.001). High-...
Lilián E Canavoso
Full Text Available The metabolism of lipids and carbohydrates related to flight activity in Panstrongylus megistus was investigated. Insects were subjected to different times of flight under laboratory conditions and changes in total lipids, lipophorin density and carbohydrates were followed in the hemolymph. Lipids and glycogen were also assayed in fat body and flight muscle. In resting insects, hemolymph lipids averaged 3.4 mg/ml and significantly increased after 45 min of flight (8.8 mg/ml, P < 0.001. High-density lipophorin was the sole lipoprotein observed in resting animals. A second fraction with lower density corresponding to low-density lipophorin appeared in insects subjected to flight. Particles from both fractions showed significant differences in diacylglycerol content and size. In resting insects, carbohydrate levels averaged 0.52 mg/ml. They sharply declined more than twofold after 15 min of flight, being undetectable in hemolymph of insects flown for 45 min. Lipid and glycogen from fat body and flight muscle decreased significantly after 45 min of flight. Taken together, the results indicate that P. megistus uses carbohydrates during the initiation of the flight after which, switching fuel for flight from carbohydrates to lipids.
Nadir Francisca Sant'Anna Nogueira
Full Text Available In this study we analyzed the microanatomy of the dorsal vessel of the triatomine Panstrongylus megistus. The organ is a tuble anatomically divided into an anterior aorta anad a posterior heart, connected to the body wall through 8 pairs of alary muscles. The heart is divided in 3 chambers by means of 2 pairs of cardiac valves. a pair of ostia can be observed in the lateral wall of each chamber. A bundle of nerve fibers was found outside the organ, running dorsally along its major axis. A group of longitudinal muscular fibers was found in the ventral portion of the vessel. The vessel was found to be lined both internally and externally by pericardial cells covered by a thin laminar membrane. Inseide the vessel the pericardial cells were disposed in layers and on the outside they formed clusters or rows.
Barros Falcao, P.H. de.
The duration of intermolt, in nymphs of the fourth instar, of P. megistus, submitted to irradiation with Cobalt 60, 24 hs after the blood meal is studied. The insects were divided in four groups of 40 and were irradiated with doses of 10, 20, 40 and 80 Gray, respectively. (M.A.C.) [pt
Maria José Costa Schuetz
Full Text Available When 4th instar nymphs of Panstrongylus megistus are fed with a saturant blood meal, there is an intense proliferation of the spermatogonia. At the end of the intermoult, the older spermatogonial cysts differentiate into 1st primary spermatocyte cysts. In the nymphs deprived of the blood meal this evolution is not observed, but a small growth of the testicular follicles occurs, due to a few mitotic divisions. This growth is observed at least, until 25 days after ecdysis. Since day 15, an autolytic process starts in the older spermatogonial cysts. The presence of exogenous juvenile hormone III (JH III does not promote the development of the germ cells in the fasting insects. There is only a small growth of the testicular follicles and the autolytic process is also observed. In the precocious adults obtained by allatectomy or precocene II treatment, germ cells are observed in all development stages, except packed and elongated spermatozoa bundels.
Garcia Simone L
Full Text Available Thermal shocks induce changes in the nuclear phenotypes that correspond to survival (heterochromatin decondensation, nuclear fusion or death (apoptosis, necrosis responses in the Malpighian tubules of Panstrongylus megistus. Since thermal tolerance increased survival and molting rate in this species following sequential shocks, we investigated whether changes in nuclear phenotypes accompanied the insect survival response to sequential thermal shocks. Fifth instar nymphs were subjected to a single heat (35 or 40°C, 1 h or cold (5 or 0°C, 1 h shock and then subjected to a second shock for 12 h at 40 or 0°C, respectively, after 8, 18, 24 and 72 h at 28°C (control temperature. As with specimen survival, sequential heat and cold shocks induced changes in frequency of the mentioned nuclear phenotypes although their patterns differed. The heat shock tolerance involved decrease in apoptosis simultaneous to increase in cell survival responses. Sequential cold shocks did not involve cell/nuclear fusion and even elicited increase in necrosis with advancing time after shocks. The temperatures of 40 and 0ºC were more effective than the temperatures of 35 and 5ºC in eliciting the heat and cold shock tolerances, respectively, as shown by cytological analysis of the nuclear phenotypes. It is concluded that different sequential thermal shocks can trigger different mechanisms of cellular protection against stress in P. megistus, favoring the insect to adapt to various ecotopes.
Justi, Silvia Andrade; Russo, Claudia A M; Mallet, Jacenir Reis dos Santos; Obara, Marcos Takashi; Galvão, Cleber
The Triatomini and Rhodniini (Hemiptera: Reduviidae) tribes include the most diverse Chagas disease vectors; however, the phylogenetic relationships within the tribes remain obscure. This study provides the most comprehensive phylogeny of Triatomini reported to date. The relationships between all of the Triatomini genera and representatives of the three Rhodniini species groups were examined in a novel molecular phylogenetic analysis based on the following six molecular markers: the mitochondrial 16S; Cytochrome Oxidase I and II (COI and COII) and Cytochrome B (Cyt B); and the nuclear 18S and 28S. Our results show that the Rhodnius prolixus and R. pictipes groups are more closely related to each other than to the R. pallescens group. For Triatomini, we demonstrate that the large complexes within the paraphyletic Triatoma genus are closely associated with their geographical distribution. Additionally, we observe that the divergence within the spinolai and flavida complex clades are higher than in the other Triatoma complexes. We propose that the spinolai and flavida complexes should be ranked under the genera Mepraia and Nesotriatoma. Finally, we conclude that a thorough morphological investigation of the paraphyletic genera Triatoma and Panstrongylus is required to accurately assign queries to natural genera.
Schaefer, Carl W.
Why are the subfamily relationships of Triatominae (Hemiptera: Reduviidae) important?-This question is really two: Is Triatominae a phylogenetically valid monophyletic subfamily; and, if it is, to what other reduviid subfamilies is it most closely related? If the answer to the first question is Yes, then what one knows about one member of Triatominae may be true for other members; if the answer is No, then no such prediction can be made. Because many members of Triatominae are of medical impo...
Galvão, Cleber; Justi, Silvia A
Chagas disease, the American trypanosomiasis, is an important neglected tropical illness caused by the flagellate protozoan Trypanosoma cruzi (Kinetoplastida, Trypanosomatidae) and transmitted by insects of the subfamily Triatominae (Hemiptera: Reduviidae). Here we provide an overview on the current knowledge about Triatominae ecology, its association with human, T. cruzi infection and the immediate consequences of habitat fragmentation. We also discuss the geographic distribution of the species and the importance of predicting their distributions to control programs. Copyright © 2015 Elsevier B.V. All rights reserved.
Y. M. Gomes
Full Text Available The haemolymph of Panstrongylus megistus showed a natural lectin activity for a wide range of vertebrate erythocytes. Agglutination was observed against all vertebrate erythrocytes tested (human ABO, duck, rabbit, mouse, sheep, chicken and cow. Cow erythrocytes showed the lowest titre. Concerning human erythrocytes, the lectin activity was similar in the types A+,B+ and AB+ while the highest activity was observed in the type O+. Determination of minimal inhibitory concentrations was carried out with human erythrocytes type O+. Agglutination was inhibited by several carbohydrates (rhamnose. D-galatose, raffinose, D-lactose and D-fucose. Rhamnose wasreported as the strongest inhibitor (0.78mM. The results suggest the presence of more than one lection in the haemolymph of P. megistus.A hemolinfa de Panstrongylus megistus mostrou uma atividade lectínica natural para eritrócitos de vários vertebrados e não mostrou especificidade para os diversos tipos de eritrócitos testados (humano ABO, pato, coelho,c amundongo,carneiro, galinha e boi. Com relação aos eritrócitos humanos a atividade lectínica foi similar nos tipos A+, B+ e AB+ enquanto a atividade mais alta foi observada no tipo O+. O título de aglutinação entre eritrócitos animais não mostrou diferença apreciável, excluindo eritrócitos de boi, que apresentaram o título mmais baixo. A determinação da concentração mínima de inibição foi realizada com eritrócitos humanos O+. A aglutinação foi inibida por vários carboidratos (ramnose, D-dalactose, rafinose, D-lactose e D-fucose. A ramnose foi o inibidor mais potente (0,78 mM. Os resultados sugerem a presença de mais de uma lectina na hemolinfa de P. megistus.
Chen, Zhuo; Zhu, Guangxiang; Wang, Jianyun; Cai, Wanzhi
Epidaus wangi Chen, Zhu, Wang & Cai, sp. nov. (Hemiptera: Heteroptera: Reduviidae: Harpactorinae) from Tibet, China, is described and illustrated based on male and female specimens. The new species is morphologically similar to E. tuberosus Yang, 1940. The new species represents the first record of Epidaus species from Tibet.
Panzera, F; Pérez, R; Panzera, Y; Ferrandis, I; Ferreiro, M J; Calleros, L
The subfamily Triatominae (Hemiptera, Reduviidae), vectors of Chagas disease, includes over 140 species. Karyotypic information is currently available for 80 of these species. This paper summarizes the chromosomal variability of the subfamily and how it may reveal aspects of genome evolution in this group. The Triatominae present a highly conserved chromosome number. All species, except 3, present 20 autosomes. The differences in chromosome number are mainly caused by variation in the number of sex chromosomes, due to the existence of 3 sex systems in males (XY, X(1)X(2)Y and X(1)X(2)X(3)Y). However, inter- and intraspecific differences in the position, quantity and meiotic behavior of constitutive heterochromatin, in the total genome size, and in the location of ribosomal 45S rRNA clusters, have revealed considerable cytogenetic variability within the subfamily. This cytogenetic diversity offers the opportunity to perform cytotaxonomic and phylogenetic studies, as well as structural, evolutionary, and functional analyses of the genome. The imminent availability of the complete genome of Rhodnius prolixus also opens new perspectives for understanding the evolution and genome expression of triatomines. The application of fluorescence in situ hybridization for the mapping of genes and sequences, as well as comparative analyses of genome homology by comparative genomic hybridization will be useful tools for understanding the genomic changes in relation to evolutionary processes such as speciation and adaptation to different environments. Copyright 2010 S. Karger AG, Basel.
Calderón-Fernández, Gustavo M; Moriconi, Débora E; Dulbecco, Andrea B; Juárez, M Patricia
The insect integument, formed by the cuticle and the underlying epidermis, is essential for insect fitness, regulation of lipid biosynthesis and storage, insect growth and feeding, together with development progress. Its participation in insecticide resistance has also been outlined. Triatoma infestans Klug (Hemiptera: Reduviidae) is one of the major vectors of Chagas disease in South America; however, genomic data are scarce. In this study, we performed a transcriptome analysis of the nymph integument in order to identify which genes are expressed and their putative role. Using the 454 GS-FLX sequencing platform, we obtained approximately 144,620 reads from the integument tissue. These reads were assembled into 6,495 isotigs and 8,504 singletons. Based on BLAST similarity searches, about 8,000 transcripts were annotated with known genes, conserved domains, and/or Gene Ontology terms.The most abundant transcripts corresponded to transcription factors and nucleic acid metabolism, membrane receptors, cell signaling, and proteins related to cytoskeleton, transport, and cell energy processes, among others. More than 10% of the transcripts-encoded proteins putatively involved in the metabolism of fatty acids and related components (fatty acid synthases, elongases, desaturases, fatty alcohol reductases), structural integument proteins, and the insecticide detoxification system (among them, cytochrome P450s, esterases, and glutathione transferases). Real-time qPCR assays were used to investigate their putative participation in the resistance mechanism. This preliminary study is the first transcriptome analysis of a triatomine integument, and together with prior biochemical information, will help further understandthe role of the integument in a wide array of mechanisms. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Justi, Silvia A.; Galv?o, Cleber; Schrago, Carlos G.
Background The family Reduviidae (Hemiptera: Heteroptera), or assassin bugs, is among the most diverse families of the true bugs, with more than 6,000 species. The subfamily Triatominae (kissing bugs) is noteworthy not simply because it is the only subfamily of the Reduviidae whose members feed on vertebrate blood but particularly because all 147 known members of the subfamily are potential Chagas disease vectors. Due to the epidemiological relevance of these species and the lack of an effici...
G. A. Marti
Full Text Available A survey of the fungal microbiota of the digestive tract of Triatoma infestans (Klug (Hemiptera: Reduviidae adults was carried out. Insects captured in the field from different provinces in Argentina, as well as individuals reared in artificial colonies, were used for dissection. Axenic cultures of the fungal species were identified and were deposited with mycological collections at La Plata , Argentina. A total of 33 fungal species, with the exception of three that were mycelia sterilia, belonging to 11 genera were identified. Thirty two species belonged to Ascomycota (Eurotiomycetes and Sordariomycetes and one to Zygomycota (Zygomycetes. The genera with the greatest number of species were Penicillium (15, Aspergillus (5, and Cladosporium (2. Among the isolated fungi, some of the species were entomopathogenic or pathogens of humans and other animals.En el presente estudio se realizó un relevamiento de la flora fúngica microbiana en tractos digestivos de adultos de Triatoma infestans (Klug (Hemiptera: Reduviidae. Se disecaron insectos capturados del campo en diferentes provincias Argentinas, así como también se utilizaron individuos de una colonia artificial. Fueron realizados cultivos axénicos de las especies fúngicas aisladas, los que fueron identificados y luego depositados en las colecciones de hongos entomopatógenos del CEPAVE La Plata , Argentina. Fueron identificadas 33 especies fúngicas perteneciente a 11 géneros. Treinta y dos especies pertenecen a Ascomycota (Eurotiomycetes y Sordariomycetes y una a Zygomycota (Zygomycetes. Los géneros con mayor número de especies fueron Penicillium (15, Aspergillus (5, y Cladosporium (2. Entre los aislamientos fúngicos, algunas de las especies encontradas son entomopatogénicas o patógenas de humanos y otros animales.
Alexandre Coletto da Silva
Full Text Available The present work shows the occurrence of an intense predatory activity on adults working Meliponinae bees (Hymenoptera, Apidae, by Apiomerus pilipes (Fabricius, 1787 (Hemiptera, Reduviidae, Harpactorinae, Apiomerini at a meliponary in the Instituto Nacional de Pesquisas da Amazônia (INPA, Manaus, Amazonas State, Brazil.O presente trabalho registra a ocorrência de intensa atividade predatória de Apiomerus pilipes (Fabricius, 1787 (Hemiptera, Reduviidae, Harpactorini, Apiomerini sobre operárias adultas de meliponíneos (Hymenoptera, Apidae, no meliponário experimental do Instituto Nacional de Pesquisas da Amazônia (INPA, Manaus, Estado do Amazonas, Brasil. O meliponário se encontra num fragmento de vegetação secundária no próprio INPA.
María L. HERNÁNDEZ
Full Text Available Triatoma infestans es el vector más importante de la enfermedad de Chagas de la Argentina. Se cita por primera vez la presencia de T. infestans (Klug (Hemiptera: Reduviidae asociado a nidos de loro barranquero Cyanoliseus patagonus (Psittasiformes: Psittacidae construidos en viviendas de adobe abandonadas. Se discuten las posibles implicancias de este hallazgo para la vigilancia entomológica del vector.
Ana Laura Carbajal de la Fuente
Full Text Available INTRODUCTION: Triatoma pseudomaculata and T. wygodzinskyi (Hemiptera: Reduviidae: Triatominae are two Brazilian vectors of Chagas disease. The first is an arboricolous species in sylvatic environment and considered a vector of T. cruzi in peridomestic structures; the second, a rupicolous species in the wild environment of no epidemiological importance. In order to test the assumption that sister species share biological traits, comparative studies of their development cycle and blood ingestion were conducted. METHODS: Eggs laid by five field females of each species were randomly selected. The nymphs were observed daily and fed on mice weekly. The time required to pass through the different stages to adulthood was recorded in days. The triatomines were weighed individually before and after feeding. The mortality rate according to each nymphal stage was calculated. RESULTS AND CONCLUSIONS: Analysis of the results shows that they display only minor biological differences even though they exhibit a distinct ecology. This suggests that the biological traits are important criteria to determine the relationship between species.INTRODUÇÃO: Triatoma pseudomaculata e T. wygodzinskyi (Hemiptera: Reduviidae: Triatominae são dois vetores Brasileiros da doença de Chagas. A primeira é uma espécie arborícola em ambiente silvestre e considerada vetor do T. cruzi em estruturas peridomesticas. A segunda é rupícola em ambientes silvestres e sem importância epidemiológica. Com o objetivo de testar a hipótese que espécies irmãs compartilham características semelhantes, realizamos um estudo comparativo do ciclo biológico e ingesta alimentar. MÉTODOS: Ovos pertencentes a cinco fêmeas de cada espécie provenientes do campo foram selecionados aleatoriamente. As ninfas foram observadas diariamente e alimentadas com camundongos semanalmente. O tempo requerido para passar até o estágio adulto foi registrado em dias. Os triatomíneos foram pesados
André A. M. Coelho
Full Text Available A transmissão da doença de Chagas ocorre, principalmente, por meio de fezes de hemípteros hematófagos (Triatominae, os quais ingerem o Trypanosoma cruzi ao se alimentarem do sangue de pessoas ou outros mamíferos infectados. Para o controle dos triatomíneos, os piretróides são os principais inseticidas utilizados. Entretanto, algumas populações de insetos demonstraram resistência a determinados piretróides, indicando a necessidade do desenvolvimento de novos inseticidas eficazes no controle desses vetores. Assim, foi avaliada a atividade inseticida de 83 extratos vegetais, pertencentes a 35 espécies diferentes, em ninfas do primeiro estádio de Dipetalogaster maxima (Uhler, 1894 (Hemiptera: Reduviidae, triatomíneo encontrado no México. Para o teste tópico, foram aplicados 50 ìg de cada extrato nos tergitos abdominais de dez ninfas, em duplicata. Como controles, foram utilizados insetos tratados com etanol, acetona ou sem nenhum tipo de tratamento. Os triatomíneos foram observados durante 28 dias. Nenhum extrato apresentou atividade inseticida significativa, entretanto, o extrato hexânico do fruto e o etanólico da casca do caule de Simarouba versicolor (Simaroubaceae inibiram a taxa de ecdise em D. maxima (40% e 25%, respectivamente. Sugere-se que estes extratos sejam quimicamente investigados e monitorados por ensaios biológicos a fim de determinar os componentes, para que estes possam ser utilizados como modelos moleculares ou como compostos biorracionais nos programas de controle de insetos.Chagas disease, also known as American Trypanosomiasis, is chiefly transmitted by faeces of haematophagous bugs (Triatominae that ingested Trypanosoma cruzi from blood of infected people or other mammals. Pyrethroids have been the main insecticides used against these insects. However, some populations of insects have shown significant levels of resistance to several pyrethroids, indicating the need of new insecticides for the control of
Walker, Andrew A; Madio, Bruno; Jin, Jiayi; Undheim, Eivind A B; Fry, Bryan G; King, Glenn F
Assassin bugs (Hemiptera: Heteroptera: Reduviidae) are venomous insects, most of which prey on invertebrates. Assassin bug venom has features in common with venoms from other animals, such as paralyzing and lethal activity when injected, and a molecular composition that includes disulfide-rich peptide neurotoxins. Uniquely, this venom also has strong liquefying activity that has been hypothesized to facilitate feeding through the narrow channel of the proboscis-a structure inherited from sap- and phloem-feeding phytophagous hemipterans and adapted during the evolution of Heteroptera into a fang and feeding structure. However, further understanding of the function of assassin bug venom is impeded by the lack of proteomic studies detailing its molecular composition.By using a combined transcriptomic/proteomic approach, we show that the venom proteome of the harpactorine assassin bug Pristhesancus plagipennis includes a complex suite of >100 proteins comprising disulfide-rich peptides, CUB domain proteins, cystatins, putative cytolytic toxins, triabin-like protein, odorant-binding protein, S1 proteases, catabolic enzymes, putative nutrient-binding proteins, plus eight families of proteins without homology to characterized proteins. S1 proteases, CUB domain proteins, putative cytolytic toxins, and other novel proteins in the 10-16-kDa mass range, were the most abundant venom components. Thus, in addition to putative neurotoxins, assassin bug venom includes a high proportion of enzymatic and cytolytic venom components likely to be well suited to tissue liquefaction. Our results also provide insight into the trophic switch to blood-feeding by the kissing bugs (Reduviidae: Triatominae). Although some protein families such as triabins occur in the venoms of both predaceous and blood-feeding reduviids, the composition of venoms produced by these two groups is revealed to differ markedly. These results provide insights into the venom evolution in the insect suborder
Justi, Silvia A.; Galvão, Cleber; Schrago, Carlos G.
Background The family Reduviidae (Hemiptera: Heteroptera), or assassin bugs, is among the most diverse families of the true bugs, with more than 6,000 species. The subfamily Triatominae (kissing bugs) is noteworthy not simply because it is the only subfamily of the Reduviidae whose members feed on vertebrate blood but particularly because all 147 known members of the subfamily are potential Chagas disease vectors. Due to the epidemiological relevance of these species and the lack of an efficient treatment and vaccine for Chagas disease, it is more common to find evolutionary studies focusing on the most relevant vectors than it is to find studies aiming to understand the evolution of the group as a whole. We present the first comprehensive phylogenetic study aiming to understand the events that led to the diversification of the Triatominae. Methodology/Principal Findings We gathered the most diverse samples of Reduviidae and Triatominae (a total of 229 Reduviidae samples, including 70 Triatominae species) and reconstructed a robust dated phylogeny with several fossil (Reduviidae and Triatominae) calibrations. Based on this information, the possible role of geological events in several of the major cladogenetic events within Triatominae was tested for the first time. We were able to not only correlate the geological changes in the Neotropics with Triatominae evolution but also add to an old discussion: Triatominae monophyly vs. paraphyly. Conclusions/Significance We found that most of the diversification events observed within the Rhodniini and Triatomini tribes are closely linked to the climatic and geological changes caused by the Andean uplift in South America and that variations in sea levels in North America also played a role in the diversification of the species of Triatoma in that region. PMID:27058599
Justi, Silvia A; Galvão, Cleber; Schrago, Carlos G
The family Reduviidae (Hemiptera: Heteroptera), or assassin bugs, is among the most diverse families of the true bugs, with more than 6,000 species. The subfamily Triatominae (kissing bugs) is noteworthy not simply because it is the only subfamily of the Reduviidae whose members feed on vertebrate blood but particularly because all 147 known members of the subfamily are potential Chagas disease vectors. Due to the epidemiological relevance of these species and the lack of an efficient treatment and vaccine for Chagas disease, it is more common to find evolutionary studies focusing on the most relevant vectors than it is to find studies aiming to understand the evolution of the group as a whole. We present the first comprehensive phylogenetic study aiming to understand the events that led to the diversification of the Triatominae. We gathered the most diverse samples of Reduviidae and Triatominae (a total of 229 Reduviidae samples, including 70 Triatominae species) and reconstructed a robust dated phylogeny with several fossil (Reduviidae and Triatominae) calibrations. Based on this information, the possible role of geological events in several of the major cladogenetic events within Triatominae was tested for the first time. We were able to not only correlate the geological changes in the Neotropics with Triatominae evolution but also add to an old discussion: Triatominae monophyly vs. paraphyly. We found that most of the diversification events observed within the Rhodniini and Triatomini tribes are closely linked to the climatic and geological changes caused by the Andean uplift in South America and that variations in sea levels in North America also played a role in the diversification of the species of Triatoma in that region.
Eduardo G. Virla
Full Text Available The corn leafhopper Dalbulus maidis (Hemiptera: Cicadellidae, is an important corn pest in most of tropical and subtropical America. This leafhopper has a rich natural enemy complex of which parasitoids and pathogens are the most studied; knowledge on its predators is limited. We noted the presence of the native assassin bug Zelus obscuridorsis (Hemiptera: Reduviidae predating diverse motile insects, including the corn leafhopper, on corn plants cultivated in household vegetable gardens in San Miguel de Tucumán (Argentina; in order to verify its predatory actions, we exposed lab-bred individuals of D. maidis to adults of Z. obscuridorsis. The predators were starved for 24 h before trials in which the corn leafhopper in different developmental stages were exposed. Zelus obscuridorsis is highly skilled in catching specimens in motion, but it was not able to prey on eggs. The predator was capable to catch and prey on nymphs and adults.
Marcio B. P. Lopes
Full Text Available Bioactivity of the latex from Parahancornia amapa (Apocynaceae on the development of Rhodnius nasutus (Hemiptera, Reduviidae, Triatominae under laboratory conditions. The aim of this study was to verify the effects of the methanolic fraction of the latex from Parahancornia amapa (Apocynaceae (PALAM on individuals of the species Rhodnius nasutus Stål (Hemiptera, Triatominae. Many of the insects treated with the substance presented deformities and these may interfere in the feeding and possibly hinder the reproductive capacity. They also presented significant mortality during the molt when compared to the control group, noting a gradual increase in mortality. The treated insects also presented delayed nymphal development (5th instar and higher adult longevity.
Palottini, Florencia; González, Andrés; Manrique, Gabriel
The filling dynamics of exocrine defensive glands is an important component of the defensive capacity of an insect in its natural environment. We studied the filling state and reloading rate of the Brindley's glands in the haematophagous Chagas disease vector Triatoma infestans (Hemiptera: Reduviidae). Quantitative analyses of isobutyric acid, the main secretion component, were carried out with glands dissected from adults under different scenarios of development, number of discharging events and feeding conditions. The alarm-pheromone function of the gland secretion was also assessed in bioassays with conspecific nymphs. Although pharate adults have their glands completely developed, these were not full until imaginal ecdysis. If kept undisturbed, the adults maintained a constant gland load, and discharged about 75% of the gland contents upon one disturbance event. While the glands can be discharged several times, full replenishing was not complete after one week, unless the insect had access to food. The escape behavior of nymphs in bioassays correlated with the chemical analyses, with nymphs showing significant avoidance only toward gland discharges from undisturbed or disturbed/fed adults. The results are discussed in reference to the feeding frequency and gregarious behavior of T. infestans under natural conditions, which suggest a relevant role of the filling dynamics of the Brindley's glands in the intraspecific communication of the insect. Copyright © 2014 Elsevier Ltd. All rights reserved.
Panzera, Francisco; Pita, Sebastián; Nattero, Julieta; Panzera, Yanina; Galvão, Cleber; Chavez, Tamara; Rojas De Arias, Antonieta; Cardozo Téllez, Lourdes; Noireau, François
Chagas disease vectors (Hemiptera-Reduviidae) comprise more than 140 blood-sucking insect species of the Triatominae subfamily. The largest genus is Triatoma, subdivided in several complexes and subcomplexes according to morphology, ecology and genetic features. One of them is the sordida subcomplex, involving four species: Triatoma sordida, T. guasayana, T. garciabesi and T. patagonica. Given the great morphological similarity of these species, their taxonomic identification, evolutionary relationships and population differentiation have been controversial for many years and even today remain under discussion. We simultaneously analyzed two chromosomal markers, C-heterochromatin distribution and 45S ribosomal genes chromosomal position, of 139 specimens from several sordida subcomplex populations from Argentina, Bolivia, Brazil and Paraguay, collected both in nature and from several established insectaries. Our results were compared with COI sequences deposited in GenBank. We recognized five chromosomal taxa with putative hybrids, which each differ in at least one chromosome marker. Most of them present significant differences in their mtDNA sequences. The chromosomal taxa here show a significant chromosome differentiation involving changes in the C-heterochromatin content and in the ribosomal clusters position. This paper identifies several erroneously classified populations by morphological methods, delimits the geographical distribution of each taxon and proposes the existence of a new cryptic species, widely distributed in Argentina. We also suggest that sordida sibling species involve closely related as well as evolutionary distant species. Taxonomic status of each chromosomal taxon is discussed considering phenotypic and genetic results previously published.
Calderón-Fernández, Gustavo Mario; Juárez, Marta Patricia
The cuticular hydrocarbons of the Triatoma sordida subcomplex (Hemiptera: Reduviidae: Triatominae) were ana-lysed by gas chromatography and their structures identified by mass spectrometry. They comprised mostly n-alkanes and methyl-branched alkanes with one-four methyl substitutions. n-alkanes consisted of a homologous series from C21-C33 and represented 33-45% of the hydrocarbon fraction; n-C29 was the major component. Methyl-branched alkanes showed alkyl chains from C24-C43. High molecular weight dimethyl and trimethylalkanes (from C35-C39) represented most of the methyl-branched fraction. A few tetramethylalkanes were also detected, comprising mostly even-numbered chains. Several components such as odd-numbered 3-methylalkanes, dimethylalkanes and trimethylalkanes of C37 and C39 showed patterns of variation that allowed the differentiation of the species and populations studied. Triatoma guasayana and Triatoma patagonica showed the most distinct hydrocarbon patterns within the subcomplex. The T. sordida populations from Brazil and Argentina showed significantly different hydrocarbon profiles that posed concerns regarding the homogeneity of the species. Triatoma garciabesi had a more complex hydrocarbon pattern, but it shared some similarity with T. sordida. The quantitative and qualitative variations in the cuticular hydrocarbons may help to elucidate the relationships between species and populations of this insect group.
Batista, V S P; Fernandes, F A; Cordeiro-Estrela, P; Sarquis, O; Lima, M M
Triatoma brasiliensis (Hemiptera: Reduviidae) is an important vector of Chagas' disease in both sylvatic and peridomestic ecotopes. Discriminating between these populations of Triatominae has been proposed as a means of investigating re-infestation rates of human dwellings. Geometric morphometrics have been widely applied in the study of Triatominae polymorphisms at species and population levels. This study characterizes morphometric differences between sylvatic and peridomestic populations, as well as between sexes in T. brasiliensis specimens from Jaguaruana, Ceará, in northeastern Brazil. No differences in either the shape or size of the cephalic capsule were apparent between sexes or ecotopes. However, the wings showed differentiation in shape and size. Sexual dimorphism was detected, with females presenting significantly higher values and conformations. Size differentiation was also evident, with sylvatic specimens being generally larger than peridomestic examples. These results indicate that differences in the wings of T. brasiliensis may be related to the existence of phenotypic plasticity, and variations in size and shape may be associated with different ecotopes, possibly as a result of conditions in each micro-habitat, such as temperature, relative humidity, food supply and density. © 2012 The Royal Entomological Society.
Germano, Mónica D; Picollo, María I
Triatoma infestans Klug (Hemiptera: Reduviidae) is the main vector of Chagas disease in Latin America. This insect has been controlled with pyrethroids since the 1980s, although the emergence of resistance to deltamethrin has decreased control success in some areas of the Gran Chaco ecoregion. The response of T. infestans to deltamethrin was evaluated per developmental stage. In addition, we evaluated the possible stage-dependent expression of deltamethrin resistance. The bioassays were conducted by topical application of the insecticide in acetone. The drop size, age at the time of exposure, and mortality measuring time were standardized per stage. The lethal dose of deltamethrin moderately increased with the developmental stage. The resistance to deltamethrin was expressed in every instar, and was the highest in the fourth- and fifth-instar nymphs. While increasing, weight plays a relevant role in lethal dose stage dependency, a number of contributing factors such as degradative metabolism are probably involved in the variability of insecticide effect and resistance described for different T. infestans developmental stages. Possible explanations for these differences and their implications on resistance management and chemical control are discussed.
Edith Natalia Gómez-Melendro
Full Text Available Introduction. Knowledge of vector insect species, their habitat and geographical distribution is crucial for determining the risk of transmission of the etiologic agents that cause disease in humans, which allows defining strategies for prevention, surveillance and control in line with the characteristics of each area. Objective. To determine the presence and public health importance of vectors of Chagas disease in the indigenous settlements of Marbacella and El Horno of the Wayúu ethnic group in the municipality of Riohacha, La Guajira, Colombia. Materials and methods. From active search, installation and inspection of biosensors and occasional catches, Hemiptera: Reduviidae: Triatomini were collected intra and in the peridomicile housing of the indigenous settlements of El Horno and Marbacella of the the Wayúu ethnic group. Indices of intra and peridomestic infestation, colonization, density, dispersion and natural infection with Trypanosoma cruzi Chagas, 1909 were calculated. Results. 79.6% (n = 90 of the specimens were collected around the homes and 20.3% (n = 23 inside the homes, all corresponding to Triatoma maculata (Erichson, 1848. The natural infection indices with T. cruzi accounted for 43.5% for Marbacella and 36% for El Horno. Conclusion. This is the first reported capture of individuals of T. maculata, considered a secondary vector of Chagas disease in Colombia, naturally infected with T. cruzi in the municipality of Riohacha expanding the geographical distribution of the species in the department of La Guajira.
Bardella, Vanessa Bellini; Pita, Sebastián; Vanzela, André Luis Laforga; Galvão, Cleber; Panzera, Francisco
The subfamily Triatominae (Hemiptera, Reduviidae) includes 150 species of blood-sucking insects, vectors of Chagas disease or American trypanosomiasis. Karyotypic information reveals a striking stability in the number of autosomes. However, this group shows substantial variability in genome size, the amount and distribution of C-heterochromatin, and the chromosome positions of 45S rDNA clusters. Here, we analysed the karyotypes of 41 species from six different genera with C-fluorescence banding in order to evaluate the base-pair richness of heterochromatic regions. Our results show a high heterogeneity in the fluorescent staining of the heterochromatin in both autosomes and sex chromosomes, never reported before within an insect subfamily with holocentric chromosomes. This technique allows a clear discrimination of the heterochromatic regions classified as similar by C-banding, constituting a new chromosome marker with taxonomic and evolutionary significance. The diverse fluorescent patterns are likely due to the amplification of different repeated sequences, reflecting an unusual dynamic rearrangement in the genomes of this subfamily. Further, we discuss the evolution of these repeated sequences in both autosomes and sex chromosomes in species of Triatominae. PMID:27759763
Gustavo Mario Calderon-Fernandez
Full Text Available The cuticular hydrocarbons of the Triatoma sordida subcomplex (Hemiptera: Reduviidae: Triatominae were ana-lysed by gas chromatography and their structures identified by mass spectrometry. They comprised mostly n-alkanes and methyl-branched alkanes with one-four methyl substitutions. n-alkanes consisted of a homologous series from C21-C33 and represented 33-45% of the hydrocarbon fraction; n-C29 was the major component. Methyl-branched alkanes showed alkyl chains from C24-C43. High molecular weight dimethyl and trimethylalkanes (from C35-C39 represented most of the methyl-branched fraction. A few tetramethylalkanes were also detected, comprising mostly even-numbered chains. Several components such as odd-numbered 3-methylalkanes, dimethylalkanes and trimethylalkanes of C37 and C39 showed patterns of variation that allowed the differentiation of the species and populations studied. Triatoma guasayana and Triatoma patagonica showed the most distinct hydrocarbon patterns within the subcomplex. The T. sordida populations from Brazil and Argentina showed significantly different hydrocarbon profiles that posed concerns regarding the homogeneity of the species. Triatoma garciabesi had a more complex hydrocarbon pattern, but it shared some similarity with T. sordida. The quantitative and qualitative variations in the cuticular hydrocarbons may help to elucidate the relationships between species and populations of this insect group.
Vanessa Bellini Bardella
Full Text Available The subfamily Triatominae (Hemiptera, Reduviidae includes 150 species of blood-sucking insects, vectors of Chagas disease or American trypanosomiasis. Karyotypic information reveals a striking stability in the number of autosomes. However, this group shows substantial variability in genome size, the amount and distribution of C-heterochromatin, and the chromosome positions of 45S rDNA clusters. Here, we analysed the karyotypes of 41 species from six different genera with C-fluorescence banding in order to evaluate the base-pair richness of heterochromatic regions. Our results show a high heterogeneity in the fluorescent staining of the heterochromatin in both autosomes and sex chromosomes, never reported before within an insect subfamily with holocentric chromosomes. This technique allows a clear discrimination of the heterochromatic regions classified as similar by C-banding, constituting a new chromosome marker with taxonomic and evolutionary significance. The diverse fluorescent patterns are likely due to the amplification of different repeated sequences, reflecting an unusual dynamic rearrangement in the genomes of this subfamily. Further, we discuss the evolution of these repeated sequences in both autosomes and sex chromosomes in species of Triatominae.
Cohen, Justin M; Wilson, Mark L; Cruz-Celis, Adriana; Ordoñez, Rosalinda; Ramsey, Janine M
Long-term control of Chagas disease requires not only interruption of the human transmission cycle of Trypanosoma cruzi Schyzotrypanum, Chagas, 1909 by controlling its domestic triatomine vectors but also surveillance to prevent reinfestation of residences from sylvatic or persistent peridomestic populations. Although a number of potential risk factors for infestation have been implicated in previous studies, the explanatory power of resulting models has been low. Two years after cessation of triatomine vector control efforts in the town of Chalcatzingo, Morelos, 78 environmental, socioecological, and spatial variables were analyzed for association with infestation by Triatoma pallidipennis Stal 1872 (Hemiptera: Reduviidae: Triatominae), the principal vector of T. cruzi. We studied 712 residences in this rural community to identify specific intradomestic and peridomestic risk factors that predicted infestation with T. pallidipennis. From numerous characteristics that were identified as correlated with infestation, we derived multivariate logistic regression models to predict residences that were more or less likely to be infested with T. pallidipennis. The most important risk factors for infestation included measurements of house age, upkeep, and spatial location in the town. The effects of certain risk factors on infestation were found to be modified by spatial characteristics of residences. The results of this study provide new information regarding risk factors for infestation by T. pallidipennis that may aid in designing sustainable disease control programs in rural Mexico.
Martinez Avandano, Eddy; Chávez Espada, Tamara; Sossa Gil, Dino; Aranda Asturizaga, Roberto; Vargas Mamani, Benigno; Vidaurre Pietro, Pablo
International audience; Triatoma bolivianasp. n. (Hemiptera: Reduviidae: Triatominae) from Sub Andean valleys of La Paz - Bolivia, related to Triatoma nigromaculata Stål, 1859. We present the description of Triatoma boliviana sp. n. based on morphological external characters of 3 males and 3 females following the keys of Lent and Wygodzinsky (1979) and Carcavallo et al. (1997). The new species are very similar to Triatoma nigromaculata and was captured in Sub Andean valleys from Muñecas Provi...
Maicon Hitoshi Maeda
Full Text Available INTRODUCTION: Entomological surveillance of Chagas disease in the Federal District of Brazil (DF, has recorded the following triatomine species: Panstrongylus megistus, P. geniculatus, P. diasi, Rhodnius neglectus, Triatoma pseudomaculata, and T. sordida. We aimed to analyze the spatial and temporal occurrence of triatomine species collected in DF, and their indices of natural infection with trypanosomes. METHODS: The Health State Secretariat of DF recorded triatomines between 2002 and 2010 in 20 administrative regions. This retrospective analysis considered the number of adults and nymphs of each species collected and infected in both intradomicile and peridomicile. RESULTS: A total of 754 triatomines were collected in 252 reported domiciles. Panstrongylus megistus was the most frequent species (65%, followed by T. pseudomaculata (14%. Of the 309 examined insects, only 3 (1% specimens of P. megistus were infected with flagellates morphologically similar to Trypanosoma cruzi. The spatial occurrence indicated a higher diversity of triatomines and frequency of T. sordida in rural areas. Moreover, there was a predominance of P. megistus in urban areas. The number of records of P. megistus in the rainy season was two times higher than that during the dry season. The largest number of triatomines was collected in November. CONCLUSIONS: The presence of P. megistus specimens infected with trypanosomes in domiciles, shows the potential risk of human infection in DF. Thus, it is essential to continue entomological surveillance, intensifying it in the rainy season and in regions of greater occurrence.
Kieran, Troy J; Gottdenker, Nicole L; Varian, Christina P; Saldaña, Azael; Means, Nicolas; Owens, Darlisha; Calzada, Jose E; Glenn, Travis C
Accurate blood meal identification is critical to understand hematophagous vector-host relationships. This study describes a customizable Next-Generation Sequencing (NGS) approach to identify blood meals from Rhodnius pallescens (Hemiptera: Reduviidae) triatomines using multiple barcoded primers and existing software to pick operational taxonomic units and match sequences for blood meal identification. We precisely identified all positive control samples using this method and further examined 74 wild-caught R. pallescens samples. With this novel blood meal identification method, we detected 13 vertebrate species in the blood meals, as well as single and multiple blood meals in individual bugs. Our results demonstrate the reliability and descriptive uses of our method. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please email: email@example.com.
Sandoval, C M; Ortiz, N; Jaimes, D; Lorosa, E; Galvão, C; Rodriguez, O; Scorza, J V; Gutiérrez, R
Belminus ferroae (Hemiptera: Reduviidae) was collected from houses in the localities of San Alberto and Santa Catalina in the municipality of Toledo, Department of Norte de Santander, Colombia. Precipitin tests revealed that the main hosts of B. ferroae are insects belonging to the order Blattodea, whose haemolymph serves as food (89.43%). A low rate of haematophagy was indicated on rodents, dogs and humans (7.32%) and no natural infection with Trypanosoma cruzi was found by either microscopic examination or polymerase chain reaction. The finding of B. ferroae inside houses, feeding primarily on Blattodea with only a minor tendency to feed on vertebrate blood, is indicative of both the evolutionary path from predator to blood-sucker taken by Triatominae and their tendency to adapt from silvatic to domestic habitats.
Background Among the vectors of Chagas disease (Hemiptera: Reduviidae:Triatominae), there are eighteen Rhodnius species described and some are difficult to identify. The aim of this article is to contribute to the specific identification of fourteen Rhodnius spp. through morphological characters of the external female genitalia. Methods Female abdomens were cut transversely. The specimens were then prepared for examination by using scanning electron microscopy. Results The careful examination of the dorsal, posterior and ventral sides revealed characteristics that allowed the identification of each of the fourteen species. Conclusion The use of external female genitalia as characteristics are proposed as a tool for specifically identifying Rhodnius species, and an identification key for these species is presented. PMID:24405517
Cinco especies nuevas de Pselliopus (Hemiptera: Heteroptera: Reduviidae: Harpactorinae: Harpactorini para México Five new species of Pselliopus (Hemiptera: Heteroptera: Reduviidae: Harpactorinae from Mexico
Full Text Available Se describen 5 especies nuevas de Pselliopus Bergroth (Reduviidae: Harpactorinae recolectadas en México (Guerrero, Hidalgo, Jalisco, Michoacán, Nayarit, Nuevo León, Oaxaca, Puebla, Querétaro, San Luis Potosí, Sinaloa, Sonora y Tamaulipas y en los Estados Unidos de América (Arizona. Pselliopus karlenae Hussey se registra por primera vez para la República Mexicana. Se ilustran caracteres diagnósticos del pronoto, del borde posterior del segmento abdominal VII, de la cápsula genital del macho (pigóforo y parámeros. Se incluye una clave para la identificación de las especies basada principalmente en los genitales masculinos.Five new species of Pselliopus Bergroth (Reduviidae: Harpactorinae from Mexico (Guerrero, Hidalgo, Jalisco,Michoacán, Nayarit, Nuevo León, Oaxaca, Puebla, Querétaro, San Luis Potosí, Sinaloa, Sonora and Tamaulipas and from the United States of America (Arizona are described. Pselliopus karlenae Hussey is a new record for Mexico. Diagnostic taxonomic characters of pronotum, posterior border of abdominal segment VII, male genital capsule (pygophore and parameres are illustrated. An identification key based mainly on the male genitalia is included.
Description of the male genitalia of Belminus rugulosus Stål and Belminus corredori Galvão & Angulo, and comments on the holotype of Parabelminus yurupucu Lent & Wygodzinsky (Hemiptera: Heteroptera: Reduviidae: Triatominae: Bolboderini).
Gil-Santana, Hélcio R; Galvão, Cleber
The male genitalia of Belminus rugulosus Stål and Belminus corredori Galvão & Angulo are described and illustrated for the first time. Comments on the holotype of Parabelminus yurupucu Lent & Wygodzinsky are presented (Hemiptera: Heteroptera: Reduviidae: Triatominae: Bolboderini). A discussion on previous data in the literature on male genitalia of species of Belminus Stål is provided.
Ibarra-Cerdeña, Carlos N; Zaldívar-Riverón, Alejandro; Peterson, A Townsend; Sánchez-Cordero, Víctor; Ramsey, Janine M
The niche conservatism hypothesis states that related species diverge in niche characteristics at lower rates than expected, given their lineage divergence. Here we analyze whether niche conservatism is a common pattern among vector species (Hemiptera: Reduviidae: Triatominae) of Trypanosoma cruzi that inhabit North and Central America, a highly heterogeneous landmass in terms of environmental gradients. Mitochondrial and nuclear loci were used in a multi-locus phylogenetic framework to reconstruct phylogenetic relationships among species and estimate time of divergence of selected clades to draw biogeographic inferences. Then, we estimated similarity between the ecological niche of sister species and tested the niche conservatism hypothesis using our best estimate of phylogeny. Triatoma is not monophyletic. A primary clade with all North and Central American (NCA) triatomine species from the genera Triatoma, Dipetalogaster, and Panstrongylus, was consistently recovered. Nearctic species within the NCA clade (T. p. protracta, T. r. rubida) diverged during the Pliocene, whereas the Neotropical species (T. phyllosoma, T. longipennis, T. dimidiata complex) are estimated to have diverged more recently, during the Pleistocene. The hypothesis of niche conservatism could not be rejected for any of six sister species pairs. Niche similarity between sister species best fits a retention model. While this framework is used here to infer niche evolution, it has a direct impact on spatial vector dynamics driven by human population movements, expansion of transportation networks and climate change scenarios.
Pita, Sebastián; Panzera, Francisco; Vela, Jesús; Mora, Pablo; Palomeque, Teresa; Lorite, Pedro
The complete mitogenome of Triatoma infestans, the main vector of Chagas disease in South America, was obtained by combining Illumina and Sanger sequencing sequence data. The 17,301bp long genome contains 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, and a control region. The number, order and orientation of mitochondrial genes are the same as in T. dimidiata, the only Triatominae mt genome published so far. The main differences between both mitogenomes are found in the control region and in the intergenic spacer between the nd1 gene and the tRNA-Ser. Comparative analysis with other Reduviidae species shows high conservation in the mt genome organization. Molecular phylogeny using all available complete mt genomes from Reduviidae species confirms the close relationship between Triatominae and Stenopodainae. Copyright © 2017 Elsevier B.V. All rights reserved.
João Aristeu da Rosa
Full Text Available The aim of this paper is to present the analysis of sexual morphological differences observed in 5th instar nymphs of the following species: Panstrongylus megistus; Rhodnius neglectus; Triatoma brasiliensis; T. infestans; T. matogrosensis and T. tibiamaculata. Male and female nymphs were examined and photographed with a Scanning Electron Microscope. The 9th segment dimensions of dorsal and ventral faces were determined through a Profile Projector. Results and statistical analysis showed significant differences: the 9th sternite is significantly broader in male than female nymphs, while in five species; tergites in female nymphs are broad and in male are narrow.
Insects found in birds' nests from Argentina. Pseudoseisura lophotes Reichenbach, 1853 and Anumbius annumbi (Vieillot, 1817) (Aves: Furnariidae), hosts of Triatoma platensis Neiva, 1913 (Hemiptera: Reduviidae: Triatominae).
The insect fauna of the nests of Pseudoseisura lophotes (Reichenbach, 1853) (Aves: Furnariidae) from Argentina was investigated. A total of 110 species (68 identified to species, 22 identified to genus, 20 identified to family) in 40 families of 10 orders of insects was found in these nests. Triatoma platensis Neiva, 1913 (Hemiptera: Reduviidae) was found again in nests of P. lophotes, corroborating after 73 years the first observations made by Mazza in 1936. The occurrence of the insects in nests of P. lophotes is compared with the previously known insect fauna in nests of A. annumbi, Furnarius rufus (Furnariidae), and Myiopsitta monachus (Psittacidae). The insect fauna in additional nests of Anumbius annumbi from the same and/or different localities is given, and used in comparisons. The first occurrence of Cuterebridae (Diptera) in birds' nests, their pupae as the overwintering stage, and the second simultaneous infestation by two species of Philornis (Diptera: Muscidae) on the same nestlings are presented. Other simultaneous infestations of different hematophagous arthropods (Hemiptera: Cimidae; Reduviidae: Triatominae, and Acari: Argasidae) are remarked and discussed.
Martínez-Ibarra, José Alejandro; Nogueda-Torres, Benjamín; Licón-Trillo, Ángel; Alejandre-Aguilar, Ricardo; Salazar-Schettino, Paz María; Vences-Blanco, Mauro Omar
The degree of reproductive isolation between Triatoma recurva (Stål) (Hemiptera: Reduviidae: Triatominae) and the six species of the genus Meccus plus T. mexicana (Herrich-Schaeffer) (Hemiptera: Reduviidae) was examined. Fertility and the segregation of morphological characteristics were examined in two generations of hybrids from crosses between these species. The percentage of couples with offspring (fertile) was low in the vast majority of sets of crosses, with the exception of that between T. recurva female and M. phyllosomus male. In all studied sets of crosses, no first- (F1) or second- (F2) generation individuals were morphologically similar to T. recurva but instead shared the morphology of the other parental species. A similar phenomenon was observed in the three successful sets of backcrosses. These results indicated that different recorded levels of reproductive fitness among T. recurva and the species of Meccus involved in this study, plus T. mexicana, are present and that they were apparently influenced by differing mechanisms of isolation. The presence of some degree of reproductive compatibility between studied triatomines of distinct genera (Meccus spp. and Triatoma spp.) reinforces the need for generic revision of the tribe Triatomini. © 2015 The Society for Vector Ecology.
Hwang, Wei Song; Weirauch, Christiane
Assassin bugs are one of the most successful clades of predatory animals based on their species numbers (∼6,800 spp.) and wide distribution in terrestrial ecosystems. Various novel prey capture strategies and remarkable prey specializations contribute to their appeal as a model to study evolutionary pathways involved in predation. Here, we reconstruct the most comprehensive reduviid phylogeny (178 taxa, 18 subfamilies) to date based on molecular data (5 markers). This phylogeny tests current hypotheses on reduviid relationships emphasizing the polyphyletic Reduviinae and the blood-feeding, disease-vectoring Triatominae, and allows us, for the first time in assassin bugs, to reconstruct ancestral states of prey associations and microhabitats. Using a fossil-calibrated molecular tree, we estimated divergence times for key events in the evolutionary history of Reduviidae. Our results indicate that the polyphyletic Reduviinae fall into 11–14 separate clades. Triatominae are paraphyletic with respect to the reduviine genus Opisthacidius in the maximum likelihood analyses; this result is in contrast to prior hypotheses that found Triatominae to be monophyletic or polyphyletic and may be due to the more comprehensive taxon and character sampling in this study. The evolution of blood-feeding may thus have occurred once or twice independently among predatory assassin bugs. All prey specialists evolved from generalist ancestors, with multiple evolutionary origins of termite and ant specializations. A bark-associated life style on tree trunks is ancestral for most of the lineages of Higher Reduviidae; living on foliage has evolved at least six times independently. Reduviidae originated in the Middle Jurassic (178 Ma), but significant lineage diversification only began in the Late Cretaceous (97 Ma). The integration of molecular phylogenetics with fossil and life history data as presented in this paper provides insights into the evolutionary history of reduviids and clears
Martínez-Ibarra, José Alejandro; Nogueda-Torres, Benjamín; Licón-Trillo, Ángel; Villagrán-Herrera, María Elena; de Diego-Cabrera, José Antonio; Montañez-Valdez, Oziel Dante; Rocha-Chávez, Gonzalo
The values of biological parameters related to the life cycles of four populations of Meccus longipennis (Reduviidae: Triatominae) were evaluated. Cohorts of each of the four studied populations from different geographical areas of Mexico were maintained under similar laboratory conditions and then compared. The population from El Saucito de Araujo was different from the other three studied populations, which could help explain the secondary importance of M. longipennis in the state of Chihuahua. This paper also supports the proposition that biological traits are important criteria for determining relationships between populations.
Rocha, D da S; da Fonseca, A H; Costa, F A; Jurberg, J; Galvão, C
Rhodnius pictipes (Hemiptera, Reduviidae) from Serra Norte, State of Pará, Brazil, acclimatized in an insectary at the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Departamento de Entomologia, Instituto Oswaldo Cruz, were fed through a silicone membrane. In order to know the viability and the efficiency of this membrane compared with insects fed on mice, the number of bloodmeals taken, period of development of the five nymphal instars, longevity of adults, average amount of blood intake in each meal and percent of mortality were observed. A total of 310 insects, were used, comprising 50 nymphs of each instar, as well as 30 male and 30 female adults. Insects fed artificially had reduced minimal and maximal periods of development than the group fed on mice. The largest relative increase of body weight was observed in the 2nd instar followed by the 1st, and the amount of blood ingested increased during the development, to the 5th instar for both groups. There were no significant differences between the groups fed artificially and in vivo according to Tukey's test for p > 0.05. The percent of mortality in the 1st instar was 18% for artificially fed and 16% for the group fed on mice; these percentages decreased as insects developed until the 4th instar, without mortality, returning to increase in the 5th instar. R. pictipes was shown to be easily adaptable to artificial feeding, and could be considered as an important and viable experimental model.
Weeks, E N I; Davies, C; Rosales, C Cordón; Yeo, M; Gezan, S A; Parra-Henao, G; Cameron, M M
In Guatemala, the most widespread vector of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae), the causative agent of Chagas disease, is Triatoma dimidiata (Latreille) (Hemiptera: Reduviidae: Triatominae). T. dimidiata is native to Guatemala and is present in both domestic and sylvatic habitats. Consequently, control of T. dimidiata is difficult because after successful elimination from homes, individual insects can recolonize homes from the surrounding environment. Therefore, intensive long-term surveillance of this species is essential to ensure adequate control is achieved. Manual inspection for signs of infestation, the current method used to monitor Triatominae throughout Central and South America, is labor and time-consuming, so cost-effective alternatives are needed. The current study compared the effectiveness of the current method of surveillance of T. dimidiata with community-based techniques of G6mez-Nuñez sensor boxes, collection and observation of bugs by householders, and presence of triatomine-like feces on walls. Although manual inspection was the most sensitive method when used alone, collection by householders also was sensitive and specific and involved less effort. Sensor boxes were not sensitive indicators of T. dimidiata infestation when used alone. Two recorded variables, visual inspection for feces and the sighting of bugs by householders, were sensitive and specific indicators of infestation, and in combination with collection by householders and sensor boxes these methods were significantly more likely to detect infestations than manual inspection alone. A surveillance program that combines multiple community-based techniques should have low cost and involve minimal effort from the government and at the same time promote sustainable community involvement in disease prevention.
Piccinali, Romina V; Gaunt, Michael W; Gürtler, Ricardo E
Prevention of vector-borne transmission of Chagas disease mainly relies on residual insecticide spraying. Despite significant success at a regional scale, house infestation with Triatoma infestans (Klug) (Hemiptera: Reduviidae) still persists in the Gran Chaco ecoregion. One key aspect is the identification of the sources of reinfestant triatomines. After detecting fine-scale genetic structure in two rural villages of Pampa del Indio, Argentine Chaco, we tested hypotheses on the putative origins of the triatomines collected at 4, 8, and 12 mo after insecticide house spraying. We genotyped 10 microsatellite loci in 262 baseline and 83 postspraying triatomines from different houses. Genetic variability was similar between baseline and postspraying populations, but 13 low-frequency alleles were not detected at postspraying. FSTs were not significant between insects collected before and after insecticide spraying at the same house in all but one case, and they clustered together in a neighbor-joining tree. A clustering algorithm detected seven genetic groups, four of them mainly composed of baseline and postspraying insects from the same house. Assignment tests suggested multiple putative sources (including the house of collection) for most postspraying insects but excluded a house located more than 9 km from the study area. The origin of three triatomines was attributed to immigration from other unaccounted sources. Our study is compatible with the hypothesis that house reinfestations in the Argentine Chaco are mostly related to residual foci (i.e., survival of insects within the same community), in agreement with field observations, spatial analysis, and morphometric studies previously published. © The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Full Text Available Assassin bugs (Reduviidae are voracious insects that prey on other arthropods. Recent evidences have pointed out that these predators also feed on plant derived substances in rare opportunities. The present study describes the feeding behavior of the reduviid Atopozelus opsimus on extrafloral nectaries of Inga vera (Fabaceae in a Neotropical savanna area. It was investigated if the insects feed more frequently of extrafloral nectar or prey, and if individuals of different stages of development vary according to feeding behavior. Notably, the results suggest that the diet of all instars and adults consist mainly of extrafloral nectar (N = 1013, in detriment of captured prey ingestion (N = 18. Also, there was no variation on feeding behavior and life stage.
Perfil electroforético de proteínas presentes en la saliva de Triatoma dimidiata (Hemiptera: Reduviidae:Triatominae Electrophoretic profile of salivary proteins of Triatoma dimidiata (Hemiptera: Reduviidae:Triatominae
Full Text Available Introducción: Los triatominos (Hemiptera: Reduviidae:Triatominae son insectos hematófagos que secretan una saliva rica en proteínas con propiedades anticoagulantes, antihistamínicas, vasodilatadoras y antiplaquetarias que facilitan su proceso de alimentación en el huésped vertebrado y favorecen la transmisión a éste de los protozoarios que se desarrollan en sus glándulas salivales. Estas proteínas son características de cada especie de triatomino y pueden ayudar a diferenciar especies, incluso aquellas fenotípicamente similares. Objetivo: Describir los perfiles electroforéticos de las proteínas salivales de Triatoma dimidiata encontrados en el intradomicilio, peridomicilio y extradomicilio en un área endémica en Santander. Materiales y métodos: Se disectaron las glándulas salivales de insectos adultos de T. dimidiata de tres municipios de Santander procedentes de colonias de laboratorio y de campo. Los perfiles de proteínas se visualizaron realizando una electroforesis de una dimensión en geles de poliacrilamida tenidos con azul de Coomassie. Resultados: Los perfiles electroforéticos de las proteínas presentes en la saliva de T. dimidiata muestran hasta 33 bandas en el rango de 23,7 a 228,8 kDa, con una alta concentración en la región 41 a 99,7 kDa. El índice de polimorfismo para T. dimidiata fue de 0,9646. Conclusión: El perfil electroforético de las proteínas salivares de T. dimidiata mostró una composición proteica compleja, donde las bandas más prominentes tienen pesos moleculares menores de 45 KDa. No se pudieron establecer agrupamientos basados en las regiones geográficas y lugares de captura, a pesar de la gran variabilidad intraespecífica observada. Sin embargo, se pudieron establecer diferencias claras a nivel de especie entre T. dimidiata y el grupo externo utilizado, P. geniculatus. Salud UIS 2009; 41: 121-127.Introduction: The triatomines (Heteroptera, Reduviidae, Triatominae are hematophagous insects
Levantamento da fauna de Triatominae (Hemiptera: Reduviidae em ambiente domiciliar e infecção natural por Trypanosomatidae no Estado de Mato Grosso do Sul Survey of Triatominae (Hemiptera: Reduviidae fauna in domestic environments and natural infection by Trypanosomatidae in the State of Mato Grosso do Sul
Paulo Silva de Almeida
Full Text Available Entre 2000 a 2004, foi realizado levantamento da fauna de Triatominae (Hemiptera: Reduviidae e exame de infecção natural por Trypanosomatidae, no Estado de Mato Grosso do Sul. Um total de 13.671 espécimes foram capturados. Na análise faunística das espécies capturadas, Triatoma sordida foi caracterizada como muito abundante, muito freqüente, constante e dominante. Os índices de infecção natural para Trypanosoma cruzi apresentaram os valores de 3,2% para Panstrongylus geniculatus, 0,6% para Rhodnius neglectus e 0,1% para Triatoma sordida, apesar do Estado de Mato Grosso do Sul apresentar-se livre da transmissão vetorial endêmica.Between 2000 and 2004, a survey of Triatominae fauna (Hemiptera: Reduviidae and examination of natural infection caused by Trypanosomatidae in the State of Mato Grosso do Sul, Brazil, was conducted. A total of 13,671 specimens were collected. Through fauna analysis on the insects that were caught, Triatoma sordida was characterized as very abundant, very frequent, constant and dominant. The rates of natural infection with Trypanosoma cruzi were 3.2% for Panstrongylus geniculatus, 0.6% for Rhodnius neglectus and 0.1% for Triatoma sordida. Nevertheless, the State of Mato Grosso do Sul is free from endemic vector transmission.
Nascimento, Juliana Damieli; Ribeiro, Aline Rimoldi; Almeida, Larissa Aguiar; de Oliveira, Jader; Mendonça, Vagner José; Cilense, Mário; da Rosa, João Aristeu
Trypanosoma cruzi, the etiological agent of Chagas disease, is transmitted by triatomines that have been described in a large number of studies. Most of those studies are related to external morphology and taxonomy, but some biochemical, genetic and physiological studies have also been published. There are a few publications in the literature about the internal organs of Triatominae, for instance the spermathecae, which are responsible for storing and maintaining the viability of the spermatozoids until the fertilization of the oocytes. This work aims to study the spermathecae of twelve species of triatomines obtained from the Triatominae Insectarium of the Faculty of Pharmaceutical Sciences, UNESP, Araraquara, using optical microscopy and scanning electron microscopy. The spermathecae of the twelve species studied showed three morphological patterns: a) P. herreri sn, P. lignarius, P. megistus, Triatoma brasiliensis, T. juazeirensis, T. sherlocki and T. tibiamaculata have spermathecae with a thin initial portion and an oval-shaped final portion; b) R. montenegrensis, R. nasutus, R. neglectus, R. pictipes and R. prolixus have tubular and winding spermathecae; c) T. infestans has oval spermathecae. In addition to the three morphological patterns, it was noted that each of the twelve species has particular features that differentiate them. Copyright © 2017 Elsevier B.V. All rights reserved.
Forero, Dimitri; Choe, Dong-Hwan; Weirauch, Christiane
Apiomerini (Reduviidae: Harpactorinae) collect plant resins with their forelegs and use these sticky substances for prey capture or maternal care. These behaviors have not been described in detail and morphological structures involved in resin gathering, transfer, and storage remain virtually undocumented. We here describe these behaviors in Apiomerus flaviventris and document the involved structures. To place them in a comparative context, we describe and document leg and abdominal structures in 14 additional species of Apiomerini that represent all but one of the 12 recent genera in the tribe. Based on these morphological data in combination with the behavioral observations on A. flaviventris, we infer behavioral and functional hypotheses for the remaining genera within the tribe Apiomerini. Setal abdominal patches for resin storage are associated with maternal care so far only documented for species of Apiomerus. Based on the occurrence of these patches in several other genera, we propose that maternal care is widespread within the tribe. Ventral abdominal glands are widespread within female Apiomerini. We propose that their products may prevent hardening of stored resins thus providing long-term supply for egg coating. Judging from the diverse setal types and arrangements on the front legs, we predict six different behavioral patterns of resin gathering within the tribe. Copyright © 2010 Wiley-Liss, Inc.
Gutiérrez-Cabrera, Ana E; Alejandre-Aguilar, Ricardo; Hernández-Martínez, Salvador; Espinoza, Bertha
Hemipterans and thysanopterans (Paneoptera: Condylognatha) differ from other insects by having an intestinal perimicrovillar membrane (PMM) which extends from the base of the microvilli to the intestinal lumen. The development and composition of the PMM in hematophagous Reduviidae depend on factors related to diet. The PMM may also allow the human parasite Trypanosoma cruzi, the etiological agent of human Chagas Disease, to establish and develop in this insect vector. We studied the PMM development in the Mexican vector of Chagas Disease, Triatoma (Meccus) pallidipennis. We describe changes in the midgut epithelial cells of insects in response to starvation, and at different times (10, 15 and 20 days) after bloodfeeding. In starved insects, the midguts showed epithelial cells closely connected to each other but apparently free of PMM with some regions being periodic acid-Schiff (PAS-Schiff) positive. In contrast, the PMM was evident and fully developed in the midgut region of insects 15 days after feeding. After this time, the PMM completely covered the microvilli and reached the midgut lumen. At 15 days following feeding the labeled PAS-Schiff increased in the epithelial apex, suggesting an increase in carbohydrates. Lectins as histochemical reagents show the presence of a variety of glycoconjugates including mannose, glucose, galactosamine, N-acetyl-galactosamine. Also present were N-acetyl-glucosamine and sialic acid which contribute to the successful establishment and replication or T. cruzi in its insect vectors. By means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the formation and structure of the PMM is confirmed at 15 days post feeding. Our results confirmed the importance of the feeding processes in the formation of the PMM and showed the nature of the biochemical composition of the vectors' intestine in this important Mexican vector of Chagas disease. Copyright © 2014 Elsevier Ltd. All rights reserved.
Full Text Available Se presenta una revisión actualizada sobre los triatominos, vectores de la enfermedad de Chagas, en aspectos como la ubicación taxonómica de las especies actualmente reconocidas, asi como de las especies encontradas en los domicilios en Colombia y del ciclo de vida del grupo en general, todo lo cual involucra el tamaño de las poblaciones, su dispersión y situaciones antrópicas que las están llevando a procesos de domiciliación. Igualmente, se hace un llamado de atención sobre las consecuencias epidemiológicas que pueden derivarse de dichas alteraciones. En Colombia, el Trypanosoma cruziafecta el 3,3% de la población y, aproximadamente, el 10% se encuentra en riesgo de adquirir la infección. En esta parasitosis intervienen tres componentes biológicos: el protozoo T.cruzi, el vector triatomino Reduviidae y el reservorio vertebrado. Debido a la alteración de los ecótopos naturales a la acción devastadora de la tala de bosques, a la construcción de viviendas con hojas de palmas y a la cacería indiscriminada de animales silvestres, entre otros, la conducta de los triatominos, insectos originalmente silvestres, ha sufrido cambios con el resultado de invasiones esporádicas o permanentes a las viviendas, lo cual está originando un cambio sustancial del comportamiento de la triada vector-huésped-parásito y, consecuentemente. de la enfermedad.
Full Text Available Mepraia spinolai is an endemic species in Chile that lives in wild and domestic habitats. It is the only species of the Reduviidae family that shows alate polymorphism; females are always wingless, but males can be found with and without wings. The M. spinolai karyotype consists of 10 pairs of autosomes and a complex sex determination system. Males from the northernmost regions I and II (latitude 18°-26° South are always winged (braquipterous and are X1X2Y, with a large Y chromosome. From region III to the metropolitan region (latitude 26°-33° South, males may be either winged or wingless but appear to be polymorphic for a small neo-Y chromosome, which may have originated by fracture of the large holocentric Y chromosome found in populations from farther north. Experimental crosses suggest that the genes for wings are linked in the Y chromosome and also that there are two cytologically indistinguishable types of neo-Y chromosomes. One form (Y1 bears a gene or genes for wings while the other (Y2 lacks such genes. Males that are X1X2Y1, X1X2Y1Y1 and X1X2Y1Y2 are winged, while the absence of Y1 (X1X2Y2 and X1X2Y2Y2 results in a wingless male. These chromosomes and morphological changes are correlated with a shift of the southern population into more arid habitats of the interior in the metropolitan region and region III.
Hart, Elwood R; Weirauch, Christiane
Abstract The New World assassin bug genus Zelus Fabricius, 1803 (Insecta: Hemiptera: Heteroptera: Reduviidae: Harpactorinae: Harpactorini) is revised based on more than 10,000 specimens. Seventy-one species are recognized and twenty-four described as new: Zelus aithaleos sp. n., Zelus amblycephalus sp. n., Zelus antiguensis sp. n., Zelus auralanus sp. n., Zelus bahiaensis sp. n., Zelus banksi sp. n., Zelus casii sp. n., Zelus championi sp. n., Zelus cordazulus sp. n., Zelus fuliginatus sp. n., Zelus gilboventris sp. n., Zelus gracilipes sp. n., Zelus grandoculus sp. n., Zelus kartaboides sp. n., Zelus lewisi sp. n., Zelus panamensis sp. n., Zelus paracephalus sp. n., Zelus rosulentus sp. n., Zelus russulumus sp. n., Zelus spatulosus sp. n., Zelus truxali sp. n., Zelus umbraculoides sp. n., Zelus umbraculus sp. n., and Zelus xouthos sp. n. Five species, Zelus araneiformis Haviland, 1931, Zelus gradarius Bergroth, 1905, Zelus modestus (Stål, 1862), Zelus subfasciatus Stål, 1860 and Zelus vittaticeps Stål, 1866, are removed from Zelus and placed incertae sedis within Harpactorini. Nine new synonyms are recognized (senior synonym in parentheses): Zelus atripes Champion, 1898 syn. nov. (=Zelus conjungens [Stål, 1860]), Zelus dispar Fabricius, 1803 syn. nov. (=Zelus pedestris Fabricius, 1803), Zelus formosus Haviland, 1931 syn. nov. (=Zelus laticornis Herrich-Schaeffer, 1853), Zelus obscuridorsis (Stål, 1860) syn. nov. (=Zelus pedestris), Zelus pallidinervus Haviland, 1931 syn. nov. (=Zelus kartabensis Haviland, 1931), Zelus personatus Berg, 1879 syn. nov. (=Zelus versicolor Herrich-Schaeffer, 1848), Zelus trimaculatus Champion, 1898 syn. nov. (=Zelus means Fabricius, 1803), Zelus trimaculicollis (Stål, 1855) syn. nov. (=Zelus means), and Zelus tristis Haviland, 1931 syn. nov. (=Zelus laticornis). Zelus conjungens (Stål, 1860) stat. rev. Is resurrected from junior synonymy with zealous armillatus (Lepeletier & Seville, 1825). Zelus ambulans Stål, 1862 stat. rev
Laura E. Fichera
Full Text Available This study reports the embryogenesis of T. infestans (Hemiptera, Reduviidae. Morphological parameters of growth sequences from oviposition until hatching (12-14 d 28ºC were established. Five periods, as percent of time of development (TD, were characterized from oviposition until hatching. The most important morphological features were: 1 formation of blastoderm within 7% of TD; 2 germ band and gastrulation within 30% of TD; 3 nerve cord, limb budding, thoracic and abdominal segmentation and formation of body cavity within 50% of TD; 4 nervous system and blastokinesis end, and development of embryonic cuticle within 65% of TD; 5 differentiation of the mouth parts, fat body, and Malphigian tubules during final stage and completion of embryo at day 12 to day 14 around hatching. These signals were chosen as appropriate morphological parameters which should enable the evaluation of embryologic modifications due to the action/s of different insecticidesEn este estudio se caracterizó el desarrollo embrionario del T. infestans (Hemiptera Reduviidae. Se establecieron parámetros morfológicos secuenciales de crecimiento desde la oviposición hasta la eclosión, (12-14 d 28ºC. Cinco períodos de crecimiento fueron determinados y expresados como fracciones porcentuales del tiempo total del desarrollo (TD hasta la eclosión. Los eventos morfológicos mas importantes fueron: 1 La formación del blastodermo hasta el 7% del TD; 2 La aparición de la banda germinativa y su gastrulación transcurridos un 30% del TD; 3 El comienzo de la formación del cordón nervioso, de las extremidades, la segmentación torácica y abdominal y la formación del mixocele cuando la embriogénesis alcanzó el 50% del TD; 4 La terminación de la blastoquinesis, el desarrollo completo del sistema nervioso y la aparición de la cutícula embrionaria hasta el 65% del TD; 5 En la etapa final de la embriogenesis se observó la diferenciación del aparato mandibular, el cuerpo graso
Full Text Available Activities of hexokinase (HK, glucose-6-phosphate dehydrogenase (G6PDH, fructose-6-phosphate kinase (F6PK, glutamate dehydrogenase (GlutDH, aspartate aminotransferase (AAT, malate dehydrogenase (MDH and glycerol-3-phosphate dehydrogenase (GPDH were determined in tissue extracts of testes and ovaries of adult Dipetalogaster maximus (Uhler and Triatoma infestans (Klug (Hemiptera: Reduviidae, insect vectors of Chagas disease. The fine structure organization of the same organs were studied by electron microscopy. Results allow the following inferences: in testes from both species, most of the glucose would be utilized through the glycolytic pathway. Amino acid catabolism for energy purposes appears to be unimportant. The number of mitochondria and the development of the rough endoplasmic reticulum in cells of the spermatogenic line indicate the occurrence of active oxidative metabolism and protein synthesis; in ovaries, levels of G6PDH indicate the existence of an active pentose pathway which would supply the NADPH required for fat and ecdysteroid synthesis. Amino acid catabolism appears to be relatively more important in ovary than in testis. Fat and glycogen are stored in follicular cells of D. maximus; oocytes of both species contain numerous fat droplets. Abundant mitocondria are present in follicular cells and oocytes. A well developed rough endoplasmic reticulum and free ribosomes are also conspicuous in these cells. The malate/aspartate H-transfer system seemed to be relatively more important than the glycerophosphate shuttle in ovaries as well in testes.
Detección de triatominos (Hemiptera: Reduviidae en ambientes domésticos y extradomésticos. Corrientes, Argentina Detection of triatomines (Hemiptera: Reduviidae in domiciliary and extra-domiciliary ecotopes. Corrientes, Argentina
Miryam Pieri Damborsky
Full Text Available Esta investigación tiene como objetivo identificar los triatominos que predominan en ambientes domésticos y extradomésticos de diferentes departamentos de la Provincia de Corrientes mediante muestreos llevados a cabo desde 1985 hasta 1995. En los ecótopos domiciliarios se detectaron Triatoma infestans (Klug, 1834, Triatoma sordida (Stål, 1859, Panstrongylus geniculatus (Latreille, 1811 y Panstrongylus megistus (Burmeister, 1835. T. infestans y T. sordida se hallaron también en ambientes peridomésticos. Triatoma platensis (Neiva, 1913, Psammolestes coreodes (Bergroth, 1911, T. sordida y Triatoma rubrovaria (Blanchard, 1843 se colectaron en biótopos silvestres. En los domicilios, se confirmó el predominio de T. infestans. Esta especie fue la única parasitada por tripanosomas cruziformes. Si bien T. sordida fue más frecuente en los ecótopos extradomésticos, se demostró su tendencia a colonizar los ambientes domésticos.In order to identify intra- and extra-domiciliary triatomines, a study in different counties of Corrientes Province, Argentina, was conducted from 1985 to 1995. Triatoma infestans (Klug, 1834, Triatoma sordida (Stål, 1859, Panstrongylus geniculatus (Latreille, 1811, and Panstrongylus megistus (Burmeister, 1835 were detected in domestic ecotopes. T. infestans and T. sordida were also found in the peridomicile. Triatoma platensis (Neiva, 1913, Psammolestes coreodes (Bergroth, 1911, T. sordida, and Triatoma rubrovaria (Blanchard, 1843 were collected in sylvatic biotopes. T. infestans was confirmed as the predominant species in the domestic environment and was the only species infected with Trypanosoma cruzi-like parasites. T. sordida was most frequent in extra-domiciliary ecotopes, but could be considered capable of colonizing human dwellings.
Toxicological, Enzymatic, and Molecular Assessment of the Insecticide Susceptibility Profile of Triatoma infestans (Hemiptera: Reduviidae, Triatominae) Populations From Rural Communities of Santa Cruz, Bolivia.
Santo-Orihuela, Pablo L; Vassena, Claudia V; Carvajal, Guillermo; Clark, Eva; Menacho, Silvio; Bozo, Ricardo; Gilman, Robert H; Bern, Caryn; Marcet, Paula L
A wide range of insecticide resistance profiles has been reported across Bolivian domestic and sylvatic populations of Triatoma infestans (Klug, 1834) (Hemiptera, Reduviidae), including some with levels proven to be a threat for vector control. In this work, the insecticide profile of domestic T. infestans was studied with standardized toxicological bioassays, in an area that has not undergone consistent vector control. F1 first-instar nymphs hatched in laboratory from bugs captured in three communities from the Santa Cruz Department were evaluated with different insecticides. Moreover, the enzymatic activity of esterases and cytochrome P450 monooxygenases was measured in individual insects to evaluate the possible mechanism of metabolic resistance to pyrethroids. In addition, the DNA sequence of sodium channel gene (kdr) was screened for two point mutations associated with pyrethroid resistance previously reported in T. infestans.All populations showed reduced susceptibility to deltamethrin and α-cypermethrin, albeit the RR50 values varied significantly among them. Increased P450 monooxygenases and permethrate esterases suggest the contribution, as detoxifying mechanisms, to the observed resistance to deltamethrin in all studied populations. No individuals presented either mutation associated to resistance in the kdr gene. The level of susceptibility to α-cypermethrin, the insecticide used by the local vector control program, falls within an acceptable range to continue its use in these populations. However, the observed RR50 values evidence the possibility of selection for resistance to pyrethroids, especially to deltamethrin. Consequently, the use of pyrethroid insecticides should be closely monitored in these communities, which should be kept under entomological surveillance and sustained interventions. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email
Di Iorio, Osvaldo; Gürtler, Ricardo E
Flight dispersal of Triatominae is affected by climatic conditions and determines the spatiotemporal patterns of house invasion and transmission of Trypanosoma cruzi Chagas (Kinetoplastida: Trypanosomatidae). We investigated the detailed time structure and temperature dependencies of flight occurrence of Triatoma infestans Klug (Hemiptera: Reduviidae) and other triatomine species in a rural village of western Argentina by taking advantage of the attraction of adult triatomines to artificial light sources. Most of the village's streetlight posts were systematically inspected for triatomines twice between sunset and midnight over 425 nights in the spring-summer seasons of 1999-2002, an unprecedented light-trap sampling effort for any triatomine species. In total, 288 adults were captured, including 122 Triatoma guasayana Wygodzinsky and Abalos, 89 T. infestans, 72 Triatoma eratyrusiformis Del Ponte, and 5 Triatoma garciabesi Carcavallo et al. Adult sex ratios were balanced in T. infestans and strongly male-biased in other species. Nearly all flight-dispersing triatomines were caught when temperatures at sunset were >20 °C (range, 16.6-31.7 °C), suggesting a putative threshold around 17-18 °C. Triatomine catches were rare on rainy days. Logistic regression analysis revealed that the proportion of nights in which at least an adult T. infestans was caught increased highly significantly with increasing temperature at sunset and was modified by collection month, with greater catches in early spring and no sex differential. This study confirms that spring represents a previously overlooked, important dispersal period of T. infestans, and shows large variations among and within Triatominae in their temporal patterns of flight occurrence, abundance, and sex ratio. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Miridae, Reduviidae and Lygaeoidea (Hemiptera collected in Colonia Carlos Pellegrini (Iberá watershed, Corrientes, Argentina Reduviidae, Miridae y Lygaeoidea (Hemiptera recolectados en Colonia Carlos Pellegrini (Esteros de Iberá, Corrientes, Argentina
María C. Melo
Full Text Available With the intention of contributing to the knowledge of the biodiversity in the protected areas of Argentina, terrestrial Heteroptera were collected in the Natural Reserve of the Iberá. The sampling site was the locality of Colonia Carlos Pellegrini (28° 32'S 57° 09'W and the following collection methods were used: sweeping, beating, fogging and light-trapping. A list is presented, with 90 species belonging to the superfamilies Reduvioidea (Reduviidae, Mirioidea (Miridae, and Lygaeoidea (Berytidae, Colobathristidae, Cymidae, Lygaeidae, Blissidae, Geocoridae, Pachygrontidae and Rhyparochromidae, 13 of them are new records for the Argentine Republic (Debilia fusciventris, Sindala granuligera, Pnirontis (Centromelus tabida, Cymoninus notabilis, Ochrimnus (Phaeochrimnus limbatipennis, Oncopeltus luctuosus, Ischnodemus gayi, Oedancala nana, Cistalia signoretii, Paracholula picta, Cholula lympha, Cholula maculatus, Pseudopachybrachius vinctus and 36 new records for the province of Corrientes.Con el objeto de contribuir al conocimiento de la biodiversidad en las áreas protegidas de la Argentina, se realizaron recoleccciones de Heteroptera terrestres en la Reserva Natural del Iberá. El sitio de muestreo fue la localidad de Colonia Carlos Pellegrini (28° 32'S 57°09'W y se utilizaron los siguientes métodos de recoleccion: rastreo, golpeteo, fogging y trampa de luz. Se presenta una lista con 90 especies pertenecientes a las superfamilias Reduvioidea (Reduviidae, Mirioidea (Miridae y Lygaeoidea (Berytidae, Colobathristidae, Cymidae, Lygaeidae, Blissidae, Geocoridae, Pachygrontidae y Rhyparochromidae, de las cuales 13 representan primeras citas para la República Argentina (Debilia fusciventris, Sindala granuligera, Pnirontis (Centromelus tabida, Cymoninus notabilis, Ochrimnus (Phaeochrimnus limbatipennis , Oncopeltus luctuosus , Ischnodemus gayi , Oedancala nana , Cistalia signoretii, Paracholula picta, Cholula lympha, Cholula maculatus
Insects found in birds' nests from Argentina: Coryphistera alaudina Burmeister, 1860 (Aves: Furnariidae), their inquiline birds and mammals, new hosts for Psammolestes coreodes Bergroth, 1911 and Triatoma platensis Neiva, 1913 (Hemiptera: Reduviidae: Triatominae).
Turienzo, Paola; Di Iorio, Osvaldo
The insect fauna in nests of Coryphistera alaudina Burmeister, 1860 (Aves: Furnariidae) were studied in the provinces of Santiago del Estero, Chaco, Córdoba, and La Pampa in Argentina. A total of 7364 insect specimens comprising 77 taxa in a total of 29 families and 7 orders was found in their nests: 40 identified to species, 23 identified to genus, and 14 identified to family. Coryphistera alaudina and some of their vertebrate inquilines are new host records for the triatomine bugs Psammolestes coreodes Bergroth, 1911 and/or Triatoma platensis Neiva, 1913 (Hemiptera: Reduviidae). The insects in the nests of C. alaudina are separated by functional guilds, and their permanence time inside the nests are presented in a new manner and discussed.
Full Text Available Geographical Distribution and Alti-latitudinal Dispersion of Some Genera and Species of the Tribe Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae - With the currently known distribution of genera and species of the tribe Triatomini Jeannel, 1919, maps and diagrams were prepared, showing the geographical area occupied by the species and their respective dispersion in grades of latitude and altitude. Two genera are not treated: Panstrongylus Berg, 1879, already published and Triatoma Laporte, 1832, that is being published partially in several articles. Genus Eratyrus Stal, 1859, has two species, while Dipetalogaster Usinger, 1939, Mepraia Mazza, Gajardo & Joerg, 1940, Paratriatoma Barber, 1938 and recently created genus Hermanlentia Jurberg & Galvão, 1997, have only one each. The study of these maps and diagrams permits a better knowledge about some ecological requirements of Chagas' disease vectors and detects gaps in the geographical distribution, where the species were not found but probably they could be prevalent
Teresa Cristina M Gonçalves
Full Text Available Biology of Triatoma pseudomaculata Corrêa & Espínola, 1964, under Laboratory Conditions (Hemiptera:Reduviidae:Triatominae - Observations were made on the evolutive cycle of Triatoma pseudomaculata, held under laboratory conditions, fed weekly on bird (pigeon. Of 60 eggs obtained, only 34 nymphs reached the adult stage in a period of X(S=398±76 days. The following parameters were observed: the time immature stages took to develop from egg to adult emergence; the occurrence of the first meal; the time-lapse between the presenting of the blood-meal and the begining of feeding; time of feeding; amount of blood ingested; variation of weight 24 hr after the blood-meal and until the next blood-meal; and the defecation pattern. The experiment was carried out for 20 months, held in BOD incubator with the average of temperature and humidity of 28±1ºC and 80±5% RU, respectively
Cantillo-Barraza, Omar; Gómez-Palacio, Andrés; Salazar, Diego; Mejía-Jaramillo, Ana María; Calle, Jaime; Triana, Omar
Information concerning to triatomine diversity and some eco-epidemiologic aspects on Margarita Island has been recorded only from two of the five counties on the island. Knowledge about species habitat and their natural infection is essential to establish the risk for Chagas disease in endemic areas. The distribution of triatomine insect fauna and its infection with Trypanosoma cruzi was described in order to establish and to stratify the risk of Chagas disease transmission. Each of the 5 counties on Margarita Island were surveyed for triatomid insects inside and outside each dwelling. In the extradomicilary area, searches were conducted in the palms and bird nests located within forests and in pastures near domiciles. Infection with T. cruzi was determined amplifying by PCR the DNA extracted from triatomine feces. Five species of Reduviidae were recovered among the 1,154 triatomines captured in the 5 counties. Triatoma maculata and Rhodnius pallescens showed high infection rates within dwellings and as well as in the peridomestic areas in Mompós and Talaigua Nuevo. On the palm trees, only R. pallescens and Eratyrus cuspidatus were found infected, and only in San Fernando and Margarita. In Cicuco, only R. pallescens was infected. Presence of Triatoma dimidiata was also ascertained. Infected triatomines were present in houses and on palm trees in all counties on the island. These observations indicate a potential risk of Chagas across the entire island; furthermore the presence of T. dimidiata, a very efficient Chagas vector, emphasizes the need to establish its epidemiological status on the island.
Costa, Jane; Peterson, A Townsend; Dujardin, Jean Pierre
All known significant insect vectors of Trypanosoma cruzi are members of the Reduviidae, subfamily Triatominae. Infections with this parasite are the cause of Chagas disease, the single most costly parasitic disease in the Western Hemisphere. The Triatominae are almost completely restricted to the Americas, with >130 species distributed in several foci of species richness and endemism; nevertheless, the processes involved in the diversification of this group remain poorly understood. The Triatoma brasiliensis species complex was recently proposed based on geography, morphology, ecology, and molecular data, and is believed to comprise two species and two subspecies. Here, we report results from a broad series of studies, in which first-generation offspring of experimental crosses were studied in terms of wing morphometry and phylogenetic position. Morphometrics, morphological, ecological and geographic analyses were consistent with the hypothesis of T. brasiliensis macromelasoma as a product of hybridization between two others (T. brasiliensis brasiliensis and T. juazeirensis). Although evidence is supportive of the hypothesis of speciation via hybridization as a mode of triatomine diversification, the case is not as-yet conclusive, and confirmation via molecular markers is necessary.
Kalsi, M; Seal, D R; Nuessly, G S; Capinera, J L; Martin, C G
The milkweed assassin bug, Zelus longipes (L.) (Hemiptera: Reduviidae), is a generalist predator and a potential biological control agent of picture-winged flies (Diptera: Ulidiidae), which cause considerable economic damage to sweet corn yields in Florida. We studied the potential of Z. longipes as a biocontrol agent of four ulidiid pests in corn fields: Euxesta stigmatias Loew, Euxesta eluta Loew, Euxesta annonae F., and Chaetopsis massyla Walker. Within-plant and within-field distributions of Z. longipes and ulidiids and functional responses of Z. longipes to ulidiid prey were determined. Highest numbers of Z. longipes and ulidiids in the R1, R2, and R3 corn stages were generally in the basal or middle leaves at 09:00 h EST, ears at 13:00 h EST, and top and tassel at 17:00 h EST. Hence, there seemed to be a coordinated migration of Z. longipes and ulidiids from the lowest to the highest parts of the corn plant during the day. Within the corn field, aggregated (clumped) distributions were most common for Z. longipes and ulidiids especially in the later R2 and R3 stages based on Taylor's power law, Iwao's patchiness regression, index of dispersion, and Lloyd's patchiness indices of dispersion. However, predator and prey populations were lower in the R1 stage, and there were inconsistent results for dispersion indices among times of day and between predators and prey. Ulidiid distributions in R1 were mostly regular (uniform) at 13:00 h EST, but aggregated at 09:00 h and 17:00 h. However, Z. longipes R1 distributions were mostly aggregated at 13:00 h, but random or regular at 09:00 h and 17:00 h EST. Handling times for male and female Z. longipes were 1.0-1.39 h and 0.67-0.97 h, respectively, and each had a type II functional response to E. stigmatias, E. eluta, and E. annonae and consumed about five flies per day. Although the population abundance of Z. longipes can vary between seasons, it appears to be a promising biocontrol agent of ulidiid flies in corn.
Full Text Available In the present work, we analysed the male meiosis, the content and distribution of heterochromatin and the number and location of nucleolus organizing regions in Microtomus lunifer (Berg, 1900 by means of standard technique, C- and fluorescent bandings, and fluorescent in situ hybridization with an 18S rDNA probe. This species is the second one cytogenetically analysed within the Hammacerinae. Its male diploid chromosome number is 31 (2n=28+X1X2Y, including a minute pair of m-chromosomes. The diploid autosomal number and the presence of m-chromosomes are similar to those reported in M. conspicillaris (Drury, 1782 (2n=28+XY. However, M. lunifer has a multiple sex chromosome system X1X2Y (male that could have originated by fragmentation of the ancestral X chromosome. Taking into account that M. conspicillaris and M. lunifer are the only two species within Reduviidae that possess m-chromosomes, the presence of this pair could be a synapomorphy for the species of this genus. C- and fluorescent bandings showed that the amount of heterochromatin in M. lunifer was small, and only a small CMA3 bright band was observed in the largest autosomal pair at one terminal region. FISH with the 18S rDNA probe demonstrated that ribosomal genes were terminally placed on the largest autosomal pair. Our present results led us to propose that the location of rDNA genes could be associated with variants of the sex chromosome systems in relation with a kind of the sex chromosome systems within this family. Furthermore, the terminal location of NOR in the largest autosomal pair allowed us to use it as a chromosome marker and, thus, to infer that the kinetic activity of both ends is not a random process, and there is an inversion of this activity.
Full Text Available The evolutionary history and times of divergence of triatomine bug lineages are estimated from molecular clocks inferred from nucleotide sequences of the small subunit SSU (18S and the second internal transcribed spacer (ITS-2 of the nuclear ribosomal DNA of these reduviids. The 18S rDNA molecular clock rate in Triatominae, and Prosorrhynchan Hemiptera in general, appears to be of 1.8% per 100 million years (my. The ITS-2 molecular clock rate in Triatominae is estimated to be around 0.4-1% per 1 my, indicating that ITS-2 evolves 23-55 times faster than 18S rDNA. Inferred chronological data about the evolution of Triatominae fit well with current hypotheses on their evolutionary histories, but suggest reconsideration of the current taxonomy of North American species complexes.
Sandoval, Claudia Magaly; Nieves, Elsa; Angulo, Víctor Manuel; Aldana, Elis
The cave organ is a sensory receptor in the antenna pedicel of some Reduviidae. This paper describes this organ for the first time in three species of the genus Belminus, Belminus corredori, Belminus ferroae and Belminus herreri, by optical and scanning electron microscopy. The structures presented a general pattern similar to one reported for other species of Triatominae.
Diez, Fernando; Coscarón, María del Carmen
Abstract In Argentina, 10 genera and 33 species of Stenopodainae (Hemiptera: Reduviidae) have been recorded. Diagnoses of the genera, subgenera and species are given, and an illustrated key to genera is provided. Six species are new records for Argentina and an additional seven species represent new records for provinces. PMID:25493054
Silva, Maria Beatriz Araújo; Barreto, Ana Virgínia Matos Sá; Silva, Helker Albuquerque da; Galvão, Cleber; Rocha, Dayse; Jurberg, José; Gurgel-Gonçalves, Rodrigo
The present study shows a descriptive analysis of triatomine occurrence and its natural Trypanosoma infection rates in the state of Pernambuco, Brazil, between 2006 and 2007. Entomological data for the species, such as specimens captured in both intra and peridomiciles and natural infection index, were obtained via domiciliary capture in 147 municipalities from 11 Regional Managements of Health. The database was obtained from a sample of insects (100% infected and 20% non-infected) sent to the Central Laboratory of Pernambuco. A total of 18,029 triatomines were analyzed from 138 municipalities of the state. Triatoma pseudomaculata (35%), Triatoma brasiliensis (34%), and Panstrongylus lutzi (25%) were the most captured species. These species also showed a widespread geographical distribution in the state. Panstrongylus megistus, Triatoma petrocchiae, Triatoma melanocephala, Triatoma sordida, Rhodnius nasutus, Rhodnius neglectus, and Triatoma infestans showed more limited geographical distribution and lower relative abundance. The parasitological research showed that 8.8% of the triatomines were naturally infected with flagellates morphologically similar to Trypanosoma cruzi and 91.3% of them were captured inside houses in 113 municipalities. P. lutzi showed the highest rates of natural infection. After the control of T. infestans, synanthropic species, such as T. brasiliensis, T. pseudomaculata, and P. lutzi, maintain the risk of T. cruzi transmission to humans in the state of Pernambuco. These species are widely distributed, and infected specimens have been found inside houses. Thus, an enhanced surveillance and vector control of Chagas disease is recommended in Pernambuco.
Maria Beatriz Araújo Silva
Full Text Available INTRODUCTION: The present study shows a descriptive analysis of triatomine occurrence and its natural Trypanosoma infection rates in the state of Pernambuco, Brazil, between 2006 and 2007. METHODS: Entomological data for the species, such as specimens captured in both intra and peridomiciles and natural infection index, were obtained via domiciliary capture in 147 municipalities from 11 Regional Managements of Health. The database was obtained from a sample of insects (100% infected and 20% non-infected sent to the Central Laboratory of Pernambuco. RESULTS: A total of 18,029 triatomines were analyzed from 138 municipalities of the state. Triatoma pseudomaculata (35%, Triatoma brasiliensis (34%, and Panstrongylus lutzi (25% were the most captured species. These species also showed a widespread geographical distribution in the state. Panstrongylus megistus, Triatoma petrocchiae, Triatoma melanocephala, Triatoma sordida, Rhodnius nasutus, Rhodnius neglectus, and Triatoma infestans showed more limited geographical distribution and lower relative abundance. The parasitological research showed that 8.8% of the triatomines were naturally infected with flagellates morphologically similar to Trypanosoma cruzi and 91.3% of them were captured inside houses in 113 municipalities. P. lutzi showed the highest rates of natural infection. CONCLUSIONS: After the control of T. infestans, synanthropic species, such as T. brasiliensis, T. pseudomaculata, and P. lutzi, maintain the risk of T. cruzi transmission to humans in the state of Pernambuco. These species are widely distributed, and infected specimens have been found inside houses. Thus, an enhanced surveillance and vector control of Chagas disease is recommended in Pernambuco.
Functional Response of the Predators Alloeocranum biannulipes (Hemiptera: Reduviidae) and Teretrius nigrescens (Coleoptera: Histeridae) Feeding on Dinoderus porcellus (Coleoptera: Bostrichidae) Infesting Yam Chips.
Loko, Y L; Djagoun, A D; Dannon, E A; Datinon, B; Dansi, A; Thomas-Odjo, A A; Tamo, M
The functional response and some predation parameters of the predators Alloeocranum biannulipes Montrouzier & Signoret (Hemiptera: Reduviidea) and Teretrius nigrescens Lewis (Coleoptera: Histeridae) were evaluated at five different densities of larvae and pupae of Dinoderus porcellus Lesne (Coleoptera: Bostrichidae) with the aim to understand their roles in the biological control of this major pest of stored yam chips. Experiments were performed in petri dishes at 25 ± 1 °C, 60 ± 10% RH, and a photoperiod of 12:12 (L:D) h in a controlled temperature room. Both predators showed Type II of functional response with respect to larvae, determined by a logistic regression model. However, T. nigrescens significantly killed more larvae of D. porcellus compared with A. biannulipes. This behavior, however, changed to a linear functional response (Type I), when pupae of D. porcellus were offered to both predators, possibly because of their immobility. In addition, there was no significant difference between T. nigrescens and A. biannulipes in terms of the killed pupae. Parameters of the Holling disc equation for both predators were estimated. Estimated handling time on larvae of D. porcellus for T. nigrescens and A. biannulipes was 0.254 and 0.677 h and the rate of searching efficiency was 0.289 and 0.348 h-1, respectively. Results indicated that T. nigrescens was a more suitable candidate for augmentative release for D. porcellus control than A. biannulipes. However, semifield studies are required to draw firm conclusions. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Ítalo A. Sherlock
Full Text Available O Malathion concentrado (0-0 dimetilfosforo ditioato de dietil mercapto - succinato foi usado para combater o Panstrongylus megistus, principal vector da doença de Chagas, numa zona endêmica do Estado da Bahia. A eficácia do malathion no controle desse triatomíneo foi constatada após ter sido aplicado três vezes, no período de um ano e meio, em intervalos senjestrais. A ação letal do inseticida tanto se faz sobre as formas ambulantes, como sobre os ovos de P. megistus. Em vista da eficácia para o controle do triatomíneo, de não terem sido observados efeitos tóxicos colaterais para o homem e do custo operacional ser relativamente baixo, os Autores concluem que o malathion é uma arma valiosa para uso nas campanhas contra os transmissores da doença de Chagas.Concentrated Malathion was used against Panstrongylus megistus, the principal local vector of Chagas' Disease, in an endemic area in the State of Bahia, Brasil. The efficacy of malathion in the controle of this triatominae was demonstrated after three applications six months apart. The insecticide is lethal to all stages of vector including the eggs. In view of its effectiveness in the control of the triatomine, the absence of any noticeable signs of intoxication in the personnel applying the insecticide and in residents of the treated houses or domestic animals, and the relatively low operational cost, the Authors conclude that malathion is a valuable weapon in campaigns to control the veçtors of Chagas Disease.
Ítalo A. Sherlock
Full Text Available O Malathion concentrado (0-0 dimetilfosforo ditioato de dietil mercapto - succinato foi usado para combater o Panstrongylus megistus, principal vector da doença de Chagas, numa zona endêmica do Estado da Bahia. A eficácia do malathion no controle desse triatomíneo foi constatada após ter sido aplicado três vezes, no período de um ano e meio, em intervalos senjestrais. A ação letal do inseticida tanto se faz sobre as formas ambulantes, como sobre os ovos de P. megistus. Em vista da eficácia para o controle do triatomíneo, de não terem sido observados efeitos tóxicos colaterais para o homem e do custo operacional ser relativamente baixo, os Autores concluem que o malathion é uma arma valiosa para uso nas campanhas contra os transmissores da doença de Chagas.
Hélcio R. Gil-Santana
Full Text Available Uma sinopse da taxonomia dos Chryxinae com chaves para os gêneros e espécies da subfamília são apresentados. Chryxus bahianus sp. nov. e o macho de Wygodzinskyella travassosi (Lent & Wygodzinsky, 1944 são descritos.Synopsis of the Chryxinae with keys to the genera and species of the subfamily are presented. Chryxus bahianus sp. nov. and the male of Wygodzinskyella travassosi (Lent & Wygodzinsky, 1944 are described.
Ribeiro, J.M.C.; Schwarz, Alexandra; Francischetti, I.M.B.
Roč. 52, č. 3 (2015), s. 351-358 ISSN 0022-2585 R&D Projects: GA MŠk LH12002; GA ČR GPP302/11/P798 Institutional support: RVO:60077344 Keywords : Chagas disease * vector biology * salivary gland * transcriptome * medical entomology Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 1.712, year: 2015
Vendrami, Daniel Pagotto; Obara, Marcos Takashi; Gurgel-Gonçalves, Rodrigo; Ceretti-Junior, Walter; Marrelli, Mauro Toledo
Triatoma sordida has a widespread distribution in Argentina, Bolivia, Brazil, Paraguay, and Uruguay and is frequently found in peridomestic environments. We investigated size and shape variability of T. sordida wings across Brazil. Field-collected adults from twelve populations were studied. For each individual female, seven landmarks on the right wing were digitalized. Shape variables derived from Procrustes superimposition were used in Principal Component Analysis (PCA). Wing size and shape variations among populations was explored by means of ANOVA. Wing centroid size was significantly different among T. sordida populations; specimens from Bahia (East) were larger than those of Mato Grosso do Sul (West). PCA based on wing shape variables showed low wing shape variability. These results reinforce previous data showing low genetic variability among T. sordida populations from Brazil. Copyright © 2017 Elsevier B.V. All rights reserved.
Esteban, Lyda; Montes, José Mauricio; Angulo, Víctor Manuel
Domestic and wild triatomines in the department of Santander have an epidemiological impact, as recently they have been linked to outbreaks of acute Chagas disease. The analysis of their diversity and temporal variation contributes to the understanding of their biology and ecology in one of the most endemic areas of the country. To analyze triatominae diversity in two regions of Santander. We analyzed the triatomine records for Santander contained in the CINTROP-UIS entomology lab database. We grouped the information for two regions: the Middle Magdalena area and the Andean region, and for each one we designed species accumulation and range-abundance curves, we calculated diversity and equality indices, and we analyzed colonization and temporal variation or persistence of the community. Ninety five percent of triatomines came from the Andean area and 4.57% from Magdalena Medio, with nine and ten species each. The dominant species in the Andean area were Rhodnius prolixus and Triatoma dimidiata while in Magdalena Medio they were Rhodnius pallescens and Panstrongylus geniculatus. We found a greater diversity and richness in Middle Magdalena compared to the Andean area. The temporal variation showed persistence of communities over time. Results revealed differences in the diversity of the two regions and the potential of wild species to occupy artificial ecotopes. Triatomines intrusion and the recent involvement of wild species in the transmission of Trypanosoma cruzi emphasize the need to further investigate the ecology of these vectors in order to guide population control strategies.
da Rosa, João Aristeu; Justino, Hernany Henrique Garcia; Nascimento, Juliana Damieli; Mendonça, Vagner José; Rocha, Claudia Solano; de Carvalho, Danila Blanco; Falcone, Rossana; Oliveira, Maria Tercília Vilela de Azeredo; Alevi, Kaio Cesar Chaboli; de Oliveira, Jader
Abstract A colony was formed from eggs of a Rhodnius sp. female collected in Taquarussu, Mato Grosso do Sul, Brazil, and its specimens were used to describe R. taquarussuensis sp. n. This species is similar to R. neglectus, but distinct characters were observed on the head, thorax, abdomen, female external genitalia and male genitalia. Chromosomal differences between the two species were also established. PMID:28769676
Guilherme Ana Lucia Falavigna
Full Text Available Em resposta a denúncias de triatomíneos em ilhas do Alto Rio Paraná foram investigados 145 ecótopos artificiais e 4 (2,8% deles encontravam-se infestados: residência, "clube", ex-escola e monte de madeira. Foram analisados 17 de 35 P. megistus coletados; 12 (70,6% apresentavam-se infectados por Trypanosoma cruzi. Ave e roedor constituíram as fontes alimentares mais comuns. Todos os exames sorológicos (56 de humanos, 18 de cães e 10 de gatos foram negativos.
Poggio, María Georgina
El presente trabajo de Tesis Doctoral se basa en el estudio citogenético clásico, molecular y evolutivo de especies de insectos hematófagos y predadores pertenecientes a las familias Cimicidae y Reduviidae del infraorden Cimicomorpha (Hemiptera: Heteroptera), que se caracterizan por presentar cromosomas holocinéticos. Se analizó el complemento cromosómico, el desarrollo meiótico masculino, el contenido, distribución y composición de la heterocromatina y el número y la localización de los gene...
Moreno, Mariana Laura; Gorla, David; Catalá, Silvia
Mepraia spinolai and Mepraia gajardoi (Hemiptera, Reduviidae) are only found in the arid regions of northern Chile. Mepraia is the only genus of Triatominae with marked wing polymorphism. Females of both species are micropterous, males of M. spinolai may be micropterous, brachypterous or macropterous, while males of M. gajardoi are always brachypterous. Because of this wing polymorphism, Mepraia can be used as a model to analyze morphological adaptations related to the flying activity and evolutionary relationships in the Triatominae. The study presented here analyses the antennal phenotype of the Mepraia species and carries out a comparison with the two species of Triatoma included in the spinolai complex (Triatoma eratyrusiformis and Triatoma breyeri). The analysis of the antennal phenotype of Mepraia showed a marked intraspecific phenotypic variability related with sex and wing condition. The number and length of multiporous trichoid sensilla (TH) on the pedicel are significantly higher and longer in winged males and are strongly reduced in females. The great length of the TH sensillum is an infrequent characteristic within Triatominae. The results show that phenetic distances between sexes are greater than between the two species. Similarity between the Mepraia species and T. eratyrusiformis was found as they all show long bristles (BR) and TH and two sized basiconic receptors (BA), a pattern that have not been observed in other species of Triatominae. These characters are not present in T. breyeri.
Jamian, Syari; Norhisham, Ahmad; Ghazali, Amal; Zakaria, Azlina; Azhar, Badrul
Integrated pest management (IPM) is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as curb economic loss with less dependency on chemical pesticides. One practice in IPM is the use of biological control agents such as predatory insects. In this study, we assessed the response of predatory natural enemies to pest outbreak and water stress, and document the habitat associations of potential pest predators. The abundances of 2 predatory insect species, namely Sycanus dichotomus and Cosmolestes picticeps (Hemiptera: Reduviidae), were compared bagworm outbreak sites and nonoutbreak sites within oil palm plantations. We also examined habitat characteristics that influence the abundances of both predatory species. We found that the abundance of C. picticeps was significantly higher in bagworm outbreak sites than in nonoutbreak sites. There were no significant differences in the abundance of S. dichotomus among outbreak and non-outbreak sites. Both species responded negatively to water stress in oil palm plantations. Concerning the relationship between predatory insect abundance and in situ habitat quality characteristics, our models explained 46.36% of variation for C. picticeps and 23.17% of variation for S. dichotomus. Both species of predatory insects thrived from the planting of multiple beneficial plants in oil palm plantations. The results suggest that C. picticeps can be used as a biological agent to control bagworm populations in oil palm plantations, but S. dichotomus has no or little potential for such ecosystem service. © 2015 Institute of Zoology, Chinese Academy of Sciences.
Triatoma melanosoma, novo status para Triatoma infestans melanosoma Martinez, Olmedo & Carcavallo, 1987 (Hemiptera: Reduviidae Triatoma melanosoma, new status for Triatoma infestans melanosoma Martinez, Olmedo & Carcavallo, 1987 (Hemiptera: Reduviidae
Full Text Available Triatoma infestans melanosoma was described in 1987 by Martinez, Olmedo & Carcavallo. In the present work the authors make a redescription, adding new characters, and based on biological and morphological aspects raise up to the level of species and being identified as Triatoma melanosoma. A detailed morphological study of the external male genitalia was made.
Carolina Magalhães dos Santos
Full Text Available The subfamily Triatominae is actually represented by 137 species distributed among 6 tribes and 19 genera. Within this subfamily, the genus Panstrongylus, Berg 1879, is composed by 13 species widespread in sylvatic, peridomestic, and domestic habitats of Neotropical regions. These species are vectors of Chagas disease and consequently are found associated with its main hosts, such as birds and mammals. Interest in species of this genus has been increasing in the last few years. Reports of several authors indicate these Triatominae to invade and colonize houses, increasing their epidemiological significance. Morphometry was used in this study to investigate correlations among possible closely related species. We measured 224 specimens among 13 species through a set of metric variables of the head. The results indicated that the genus Panstrongylus seems to be homogeneous since 10 of the 14 species were shown to be closely related.
Full Text Available Os autores descreveram as características morfológicas de Triatoma klugi Carcavallo, Jurberg, Lent & Galvão, 2001 pertencente ao grupo de espécies que compõem o "complexo T. oliveirai". Até o presente tem sido difícil separar essas espécies com base nas características ninfais, o que justifica o desenvolvimento deste trabalho. Os espécimes foram coletados em frestas de rochas no morro Malavok na localidade de Linha Brasil, município de Nova Petrópolis, no Estado do Rio Grande do Sul. O local de captura dos triatomíneos situa-se entre 700 e 800 m de altitude (29º18'38''S, 51º04'57''W. Juntamente com T. oliveirai (Neiva, Pinto & Lent, 1939, espécie morfologicamente mais próxima, são as únicas do complexo que não foram encontradas, até o momento, no Estado do Mato Grosso, Mato Grosso do Sul e Goiás, Brasil. Em condições experimentais, já foi testada e comprovada a sua susceptibilidade à infecção pelo Trypanosoma cruzi (Chagas, 1909 e Trypanosoma rangeli (Tejera, 1920. A análise comparativa das ornamentações do exocório dos ovos e de três estádios ninfais de T. klugi por microscopia óptica e microscopia eletrônica de varredura mostrou algumas particularidades morfológicas, com destaque para: a face ventral da cabeça, o sulco estridulatório e os últimos segmentos abdominais (IX, X - futura genitália e XI - tubo anal. Esses dados contribuem para a ampliação dos parâmetros diferenciais visando à diagnose de T. klugi durante o seu desenvolvimento ninfal.The authors had described the morphologic characteristics of Triatoma klugi Carcavallo, Jurberg, Lent & Galvão, 2001 to the group of species belonging to "T. oliveirai complex". Until the moment it has been difficult to separate on the nymphs characteristics basis these species, what it justifies the development of this work. The specimens had been collected in openings of rocks in the Malavok mount in the locality of Linha Brazil, city of Nova Petrópolis, in the State of Rio Grande do Sul. The local of capture of the Triatominae is placed enters 700 and 800 m of altitud (29º18'38''S, 51º04'57''W. Together with T. oliveirai (Neiva, Pinto & Lent, 1939, its morphologically related species, is the only ones of the complex that had not been found, until the moment, in the State of Mato Grosso, Mato Grosso do Sul and Goiás, Brazil. In experimental conditions, already it was tested and proven its susceptibilities to the infection for Trypanosoma cruzi (Chagas, 1909 and Trypanosoma rangeli (Tejera, 1920. The comparative analysis of the ornaments of the exocorium of eggs and of three nymphs of T. klugi by optic microscopy and scanning electron microscopy showed some morphologic particularities, with prominence for: the ventral face of the head, the stridulatory sulcus and the last abdominal segments (IX, X - future genitalia and XI - anal duct. These data contribute for the magnifying of the distinguishing parameters aiming at diagnosis of T. klugi during its nymphal development.
Performance of yeast-baited traps with Triatoma sordida, Triatoma brasiliensis, Triatoma pseudomaculata, and Panstrongylus megistus in laboratory assays Rendimiento de trampas cebadas con levaduras en la captura de Triatoma sordida, Triatoma brasiliensis, Triatoma pseudomaculata y Panstrongylus megistus en experimentos de laboratorio
Herton H. R. Pires
Full Text Available The effectiveness of a trap for triatomines baited with yeast cultures has been previously demonstrated for Triatoma infestans in laboratory assays. We report here results from laboratory assays testing yeast traps for Triatoma sordida, Triatoma brasiliensis, Triatoma pseudomaculata, and Panstrongylus megistus. All assays were conducted in an open experimental arena 100 cm X 100 cm, with two traps placed at opposite sides of the arena. One of the traps contained a yeast culture, and the other trap contained a saccharose solution as a control. Two series of experiments were done, one without a refuge for the insects and one with a refuge. The results obtained clearly demonstrated that the yeast-baited traps were effective in the laboratory in capturing both T. sordida and P. megistus. For T. sordida, yeast-baited traps captured significantly more bugs than did the control traps (t test P value = 0.03. For P. megistus, when a refuge was provided during the assay, yeast-baited traps also captured significantly more bugs than did the control traps (t test P value = 0.006. In the experiments with T. brasiliensis and T. pseudomaculata, both traps captured some insects, but the yeast traps captured many fewer bugs than was true with the T. sordida and P. megistus bugs. These results indicate that, in the laboratory, yeast traps can capture considerable numbers of T. sordida and P. megistus in one night. We discuss the potential use of yeast traps for detecting and capturing both triatomine species.Con anterioridad se ha demostrado la eficacia de las trampas cebadas con cultivos de levaduras (TCL para capturar Triatoma infestans en experimentos de laboratorio. En el presente estudio se describen los resultados obtenidos con estas trampas para capturar T. sordida, T. brasiliensis, T. pseudomaculata y Panstrongylus megistus, también en experimentos de laboratorio. Todos los experimentos fueron realizados en un recinto experimental abierto de 100 cm por
Jose Eloy dos Santos Jr
Full Text Available Introduction Panstrongylus megistus is commonly found in wild environments of the State of Rio Grande do Sul, Brazil. The aim of this study was to characterize the network of refuges used by triatomine in a forest fragment of Porto Alegre and to identify Trypanosoma cruzi infection, associated hosts and the epidemiological importance of both hosts and triatomines. Methods Techniques including the spool-and-line method and active searching (transects were used to identify natural foci. Results The food source for each triatomine was determined using the precipitin test, and the infection of marsupials was determined by xenodiagnosis. A total of 33 adults (domestic environment and 27 nymphs (wild environment of P. megistus were found in addition to 43 Didelphis albiventris specimens. The infection rates of triatomine adults, triatomine nymphs and opossums with T. cruzi I were 64%, 73% and 69%, respectively. Birds, rodents and opossums were the main resources used by triatomine. Conclusions This work presents the first characterization of a natural focus of P. megistus in Rio Grande do Sul. The natural characteristics of this focus and its implication in the transmission of T. cruzi are discussed.
Marina Vianna Braga
Full Text Available Os efeitos da privação alimentar sobre a oogênese de P. megistus foram estudados em laboratório. Imediatamente após a ecdise imaginária, foram formados seis grupos (GI a GVI de 15 casais, que receberam alimentação da seguinte maneira: GI -- no 5º e no 25º dias de jejum; GII -- no 5º e 35º dias; GIII -- no 5º e no 45º dias; GIV -- no 20º dia; GV -- no 30º dia; GVI -- no 40º dia de jejum. Após esses períodos, todos os grupos receberam alimentação a cada 15 dias. O grupo de controle foi formado por 15 casais, alimentados no 5º dia após a ecdise imaginária e, subseqüentemente, a cada 15 dias. GI apresentou o maior número de acasalamentos, produziu mais ovos e maior fertilidade. GII teve maior vida média, maior fecundidade e maior número de eclosões. GIII apresentou o menor período de sobrevivência, baixas fecundidade, fertilidade e eclosões. GVI apresentou os resultados menos favoráveis em todos os parâmetros, exceto em relação ao período de pré-ovipostura. O grupo de controle apresentou os melhores resultados em todos os parâmetros.The effects of various levels of food deprivation on the oogenesis of P. megistus was studied. Immediately after the imaginal ecdysis, six groups (GI to GVI of 15 couples each were formed. Each group was fed as follows: GI -- on days 5 and 25; G-II -- on days 5 and 35; GIII -- on days 5 and 45; GIV -- on day 20; GV -- on day 30; GVI -- on day 40 after the imaginal ecdysis. After the established fasting period, all groups were fed fortnightly. Fifteen couples were in the control group (CG, which was fed on the day 5 after the imaginal ecdysis and subsequently fortnightly. GI produced more eggs, matings and fertile eggs. GII had longer life spans, higher fecundity and hatchings. GIII had a shorter life span, low fecundity, fertility and hatchings. GVI presented the least favorable results for all parameters, except for the pre-oviposition period. The CG had the best results in all
Determinantes do processo de infestação domiciliar por Panstrongylus megistus: o papel da habitação e do desmatamento Determinants of the dwelling infestation process by Panstrongylus megistus: the role of housing and deforesting
Full Text Available A qualidade das habitações e o desmatamento foram estudados em Caconde e São José do Rio Pardo, municípios paulistas com taxas diferenciadas de infestação domiciliar por Panstrongylus megistus, e com desenvolvimento sócio-econômico dessemelhante. Para o conhecimento da qualidade das habitações recorreu-se a dados registrados na Superintendência de Controle de Endemias (SUCEN durante a década de 70; o estudo do desmatamento foi realizado em mapas, construídos por nós a partir de fotografias aéreas, obtidas em vôos realizados pela Secretaria de Agricultura em 1972 e 1983. A análise sócio-econômica baseou-se nas informações do Censo Agro-pecuário e em entrevistas com agrônomos dos municípios. O estudo mostrou uma situação de maior precariedade das casas em Caconde. Essa situação decorre do menor desenvolvimento sócio-econômico deste município, confirmando assim uma tendência já demonstrada em pesquisas anteriores. O desmatamento foi mais intenso em São José, onde o desenvolvimento social é maior e no qual à taxa de infestação é menor, fato que mostra um comportamento oposto entre os dois determinantes nestes municípios. Os vínculos entre o desmatamento e o maior desenvolvimento sócio-econômico pode também ser demonstrado na medida em que se pode relacionar a atividade produtiva com a destruição da cobertura vegetal natural. Cabe sublinhar que esta tendência de efeito oposto do desmatamento não inverteu o resultado final, ou seja, que o confronto dessas forças determinantes resultou ainda numa taxa de infestação superior em Caconde, área de menor desenvolvimento social. A existência dessas tendências opostas entre os determinantes revela, desse modo, uma maior complexidade no processo de infestação por P. megistus, sem produzir, no entanto, reversão do resultado final.This study investigates the housing conditions and deforesting in Caconde and São José do Rio Pardo, neighbouring towns
Martins, Luciamáre P A; Castanho, Roberto E P; Therezo, Altino L S; Ribeiro, Aline R; Lima, Luciana; Teixeira, Marta M G; Sperança, Márcia A; Rodrigues, Vera L C; da Rosa, João A
An isolate of Trypanosoma cruzi obtained from P. megistus captured in the peridomicile area of a home in Santo Antonio do Jardim city in the State of Sao Paulo, denominated T. cruzi Mogi, was characterized biologically and molecularly. The RFLP analysis of the D7 divergent domain in the 24Sα rDNA and of the mini-exon positioned the T. cruzi isolate within the TcI group. Phylogenetic analysis performed with the trypanosomatid barcode confirmed that the isolate belongs to the TcI group, with high homology to the 3014 c1 T.cruzi strain. The biological characterization of the isolate in rats showed a prepatent period of about 8 days, low parasitemia and tropism for cardiac, skeletal and colonic muscles. In Swiss mice the T. cruzi Mogi isolate showed a prepatent period of about 22 days, intermittent parasitemia in some animals, and tropism for cardiac and colonic muscles. Despite the inherent difficulty of identifying correlations amongst the molecular and biological characteristics of different T. cruzi groups, the tropism for colonic muscle demonstrated by T. cruzi Mogi represented a peculiarity of this isolate within the TcI group.
Conclusion: Synthetic girgensohnine analogues, and C. flexuosus and C. sinensis essential oils showed insecticidal activity in R. prolixus. Analogue 3 showed the greatest insecticidal activity among all molecules and oils evaluated under our laboratory conditions.
Lima-Neiva, Vanessa; Gonçalves, Teresa C M; Bastos, Leonardo S; Gumiel, Marcia; Correia, Nathália C; Silva, Catia C; Almeida, Carlos E; Costa, Jane
Triatoma sherlocki Papa, Jurberg, Carcavallo, Cerqueira & Barata was described in 2002, based on specimens caught in the wild in the municipality of Gentio do Ouro, Bahia, Brazil. In 2009, nymphs and adults were detected inside homes and sylvatic specimens were positive for Trypanosoma cruzi (Chagas). No information on the bionomics of T. sherlocki exists, although such data are considered essential to estimate its vector and colonization potential in domestic environments. Herein, the biological cycle of T. sherlocki was studied based on 123 eggs, with nymphs and adults fed on Mus musculus (Linnaeus). Nymphal development time phases, number of meals consumed, and stage-specific mortality rates were analyzed. Survival time under starvation conditions was measured between ecdysis and death among 50 nymphs (first to fifth instar) and 50 male and female adults. The median development time from egg to adult was 621.0 (CI: 489-656) d. The number of meals consumed ranged from 1 to 20 for nymphs of the first to fifth instar. The fifth instar showed the greatest resistance to starvation, with a mean of 156.5 d. The high number of meals consumed by T. sherlocki favored infection with and transmission of T. cruzi. The full development of this species under laboratory conditions with a low mortality rate indicates that this vector presents biological characteristics that may contribute to its adaptation to artificial human ecotopes. Its high resistance to starvation emphasizes the importance of entomological surveillance for this species. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Pessoa, Grasielle Caldas D'Ávila; Sousa, Tais Nóbrega de; Sonoda, Ivan Vieira; Diotaiuti, Liléia
Triatoma sordida is a species that transmits Trypanosoma cruzi to humans. In Brazil, T. sordida currently deserves special attention because of its wide distribution, tendency to invade domestic environments and vectorial competence. For the planning and execution of control protocols to be effective against Triatominae, they must consider its population structure. In this context, this study aimed to characterise the genetic variability of T. sordida populations collected in areas with persistent infestations from Minas Gerais, Brazil. Levels of genetic variation and population structure were determined in peridomestic T. sordida by sequencing a polymorphic region of the mitochondrial cytochrome b gene. Low nucleotide and haplotype diversity were observed for all 14 sampled areas; π values ranged from 0.002-0.006. Most obtained haplotypes occurred at low frequencies, and some were exclusive to only one of the studied populations. Interpopulation genetic diversity analysis revealed strong genetic structuring. Furthermore, the genetic variability of Brazilian populations is small compared to that of Argentinean and Bolivian specimens. The possible factors related to the reduced genetic variability and strong genetic structuring obtained for studied populations are discussed in this paper.
Alevi, K C C; Imperador, C H L; Moreira, F F F; Jurberg, J; Azeredo-Oliveira, M T V
Using classic morphometric techniques to examine the head and thorax of Triatoma specimens, researchers identified a possible taxonomic problem involving T. arthurneivai (Lent & Martins) and T. wygodzinskyi (Lent). A recent geometric morphometric study indicated that the insects captured outside the Serra do Cipó region, State of Minas Gerais, Brazil, were T. wygodzinskyi. The misidentification of T. arthurneivai as T. wygodzinskyi could result in several problems associated with entoepidemiological lifting, the biological characterization of the species, and phylogenetic reconstruction. For the first time, we describe the use of cytogenetic analysis as a tool for differentiation between T. arthurneivai and T. wygodzinskyi. The results indicated that both species had the same number of chromosomes 2n = 22 (20A + XY). However, analyses of spermatocytes during early prophase indicated that it was possible to differentiate T. arthurneivai and T. wygodzinskyi, because only T. arthurneivai exhibited heteropycnotic blocks distributed in the chromatin. Therefore, we highlight the analysis of spermatocytes as a taxonomic tool for the characterization of T. arthurneivai and T. wygodzinskyi, and suggest that the technique can be used for entoepidemiological lifting in vector control programs. Thus, the results presented here, in conjunction with morphometric analyses, are of utmost taxonomic and epidemiological importance for the identification of T. arthurneivai and T. wygodzinskyi specimens.
Nattero, Julieta; Pita, Sebastián; Calleros, Lucía; Crocco, Liliana; Panzera, Yanina; Rodríguez, Claudia S; Panzera, Francisco
The epidemiological importance of Chagas disease vectors largely depends on their spreading ability and adaptation to domestic habitats. Triatoma patagonica is a secondary vector of Chagas disease endemic of Argentina, and it has been found colonizing domiciles and most commonly peridomiciliary structures in several Argentine provinces and morphological variation along its distribution range have been described. To asses if population differentiation represents geographic variants or true biological species, multiple genetic and phenotypic approaches and laboratory cross-breeding were performed in T. patagonica peridomestic populations. Analyses of chromatic variation of forewings, their size and the content of C-heterochromatin on chromosomes revealed that populations are structured following a North-South latitudinal variation. Cytochrome c oxidase I mitochondrial gene (COI) nucleotide analysis showed a mean genetic distance of 5.2% between the most distant populations. The cross-breeding experiments suggest a partial reproductive isolation between some populations with 40% of couples not laying eggs and low hatching efficiency. Our findings reveal phenotypic and genetic variations that suggest an incipient differentiation processes among T. patagonica populations with a pronounced phenotypic and genetic divergence between the most distant populations. The population differentiation here reported is probably related to differential environmental conditions and it could reflect the occurrence of an incipient speciation process in T. patagonica.
Nogueira Brito, Raíssa; Diotaiuti, Liléia; Celencina Fagundes Gomes, Anália; de Cássia Moreira de Souza, Rita; Abad-Franch, Fernando
Triatoma costalimai Verano & Galvão, a little-known vector of Trypanosoma cruzi Chagas, occupies rocky environments in the Brazilian Cerrado and occasionally infests man-made habitats. Entomological surveillance records show that T. costalimai occurs fairly often inside and around houses in south-eastern Tocantins, Brazil, with 859 specimens reported in 2005-2014. Most adults were caught indoors, and breeding colonies were found inside and around houses. Trypanosoma cruzi was detected in 13.7% of 839 bugs. These data suggest that T. costalimai can contribute to T. cruzi transmission in human environments, underscoring the need for long-term entomological-epidemiological surveillance wherever native Chagas disease vectors occur. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Waniek, Peter J; Araújo, Catarina A C; Momoli, Marisa M; Azambuja, Patricia; Jansen, Ana M; Genta, Fernando A
Using specific oligonucleotides, 5'- and 3'-RACE and sequencing, two cDNAs encoding serine carboxypeptidases (tbscp-1 and tbscp-2) from the midgut of the blood sucking heteropteran Triatoma brasiliensis were identified. Both cDNAs with an open reading frame of 1389bp, encode serine carboxypeptidase precursors of 463 amino acid residues, which possess a signal peptide cleavage site after Ala19. Analysis of tbscp-1 and tbscp-2 genomic DNA showed an absence of introns in both sequences and the presence of a further intron-free SCP encoding gene (tbscp-2b). By reverse transcription polymerase chain reaction (RT-PCR), tbscp-1 and tbscp-2 transcript abundance was found similarly in fifth instar nymphs at different days after feeding (daf), high in the posterior midgut (small intestine), lower in the anterior midgut (stomach) and fat body and almost undetectable in the salivary glands. In the anterior, middle and posterior regions of the small intestine at 5daf the transcript abundance of both genes was almost identical. Also in adult female and male insects at 5daf both genes showed the strongest signal in the posterior midgut. Molecular modeling suggested that TBSCP-1 has carboxypeptidase D activity; activities against Hippuryl-Phenylalanine and Hippuryl-Arginine were also located at the posterior midgut, both were induced after blood feeding. Treatment of the posterior midgut extracts with the serine protease inhibitor PMSF strongly reduced carboxypeptidase activity. These findings suggest that triatomines might use serine carboxypeptidases, which are usually found in lysosomes, as digestive enzymes in the posterior midgut lumen, from which TBSCP-1 and TBSCP-2 are possible candidates to fulfill this function. Copyright © 2014 Elsevier Ltd. All rights reserved.
De Oliveira, Jader; Mendonça, Vagner J; De Araújo, Renato Freitas; Nascimento, Eliane Góes; Da Rosa, João Aristeu
Triatoma melanocephala Neiva & Pinto is found in the Brazilian states of Bahia, Paraíba, Pernambuco, Rio Grande do Norte, and Sergipe. In addition to the species' specific description, eight other articles on this insect were found in the literature. In this study, data was obtained on the morphology, morphometry, and life cycle of T. melanocephala, since this vector is of epidemiological and taxonomic importance. The specimens studied were obtained from a colony that has been kept at the Triatomine Insectarium of the College of Pharmaceutical Sciences of São Paulo State University's in Brazil. The morphological studies were performed using scanning electron microscopy. These studies characterized the eggs, the external adult female genitalia, and the ninth ventral abdominal segments of male and female nymphs. The morphometric studies characterized the five nymphal instars and the adult stage by measuring the head, thorax, abdomen, antennae, and mouthparts parameters. The life cycle of T. melanocephala was developed starting by 15 couples in the fifth instar. They were fed on Swiss mice every two weeks and observed daily. During daily observation, minimum temperature, maximum temperature, and relative humidity of the laboratory were measured. The results of the biological, morphometric, and morphological studies have increased the knowledge available on T. melanocephala.
João A da Rosa
Full Text Available OBJETIVO: Estudar morfologicamente ovos de T. circummaculata e T. rubrovaria. MÉTODOS: Quarenta ovos das duas espécies foram mensurados por meio de projetor de perfil Nikon modelo 6C, e utilizado o teste Student, para execução da análise estatística. As observações morfológicas foram feitas em microscópio eletrônico de varredura JEOL, modelo JSM-T330A. RESULTADOS/CONCLUSÕES: A análise estatística revelou que os ovos e as cascas de ovos de T. rubrovaria são significativamente maiores que os de T. circummaculata. Observações microscópicas mostraram que a borda corial, assim como a goteira espermática, são bem mais evidentes nos ovos de T. rubrovaria que nos de T. circummaculata. O exocório das duas espécies é formado por áreas poligonais, que são hexagonais em sua maioria. Foram observados também o momento da eclosão do embrião e os detalhes das exúvias embrionárias.
Liu, Qin; Guo, Yun-Hai; Zhang, Yi; Zhou, Zheng-Bin; Zhang, Liang-Liang; Zhu, Dan; Zhou, Xiao-Nong
Triatomines, also known as kissing bugs, which are found throughout the world and especially in Latin America, are well known natural vectors that transmit American trypanosomiasis, also called Chagas disease. In China, the presence of two species of Triatoma (Triatoma rubrofasciata and T. sinica) was recorded in the past. Due to the growing population and the increasing risk of the global spread of Chagas disease, triatomines became a potential public health nuisance, and in 2016, we started monitoring triatomine activities in southern China. Triatomine specimens were collected by the National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, and identified by their morphological characteristics under a dissecting microscope. In addition to morphological analysis, the genomic DNA of the specimens was extracted, and the mitochondrial 16S rRNA, the cytochrome b (CytB) gene and the nuclear ribosomal 28S rRNA gene were PCR-amplified to analyze and confirm the species genetically. One female adult insect and one male adult insect were collected in a dwelling in the rural area of Shunde County, Foshan City, Guangdong Province, China (22°42'44.63″N, 113°08'45.34″E). The results from the morphological and genetic analyses indicated that these triatomines were T. rubrofasciata. This is the first time that the occurrence of T. rubrofasciata has been confirmed in Foshan City, Guangdong Province in southern China. Further studies are needed to reach a clearer understanding of the ecology of this species of triatomine, since it has been found to be naturally infected by Trypanosoma cruzi and T. conorhini and there is evidence of its domiciliation capabilities.
Alevi, Kaio Cesar Chaboli; de Oliveira, Jader; de Azeredo-Oliveira, Maria Tercília Vilela; da Rosa, João Aristeu
Triatomines have been grouped into complexes and subcomplexes based largely on morphological and geographical distribution. Although these groupings are not formally recognised as taxonomic ranks, they are likely monophyletic. However, recent studies have demonstrated that some subcomplexes from South America did not form monophyletic groups, and reorganisations have been suggested. One suggested reorganisation is to exclude Triatoma vitticeps, T. melanocephala, and T. tibiamaculata from the T. brasiliensis subcomplex. However, T. vitticeps and T. melanocephala exhibit several similar characteristics, including morphologic, cytogenetic, and phylogenetic features, a factor which supports the creation of a new subcomplex. Thus, this study aimed to describe the T. vitticeps subcomplex. T. vitticeps and T. melanocephala are sister species and share a phylogenetic relationship, several similar morphological characteristics, the same composition of constitutive heterochromatin (Xs CG-rich and Y AT-rich), the same karyotype (2n = 20A + X 1 X 2 X 3 Y), and the same meiotic behaviour during spermatogenesis. Based on karyosystematics, for example, the T. vitticeps subcomplex may differ from all of the other subcomplexes from South America, as well as from the Rhodniini tribe and the genus Panstrongylus. We argue that the case of agmatoploidy involving the X chromosome was responsible for the karyotype divergence of this subcomplex in relation to the other South America subcomplexes. Based on the phenotypic characteristics (morphology) and genotypes (cytogenetics and molecular features), we propose the creation of the monophyletic T. vitticeps subcomplex, which we believe is distinct from all other subcomplexes from South America.
Gómez-Palacio, Andrés; Triana, Omar; Jaramillo-O, Nicolás; Dotson, Ellen M; Marcet, Paula L
Triatoma dimidiata is currently the main vector of Chagas disease in Mexico, most Central American countries and several zones of Ecuador and Colombia. Although this species has been the subject of several recent phylogeographic studies, the relationship among different populations within the species remains unclear. To elucidate the population genetic structure of T. dimidiata in Colombia, we analyzed individuals from distinct geographical locations using the cytochrome c oxidase subunit 1 gene and 7 microsatellite loci. A clear genetic differentiation was observed among specimens from three Colombian eco-geographical regions: Inter Andean Valleys, Caribbean Plains and Sierra Nevada de Santa Marta mountain (SNSM). Additionally, evidence of genetic subdivision was found within the Caribbean Plains region as well as moderate gene flow between the populations from the Caribbean Plains and SNSM regions. The genetic differentiation found among Colombian populations correlates, albeit weakly, with an isolation-by-distance model (IBD). The genetic heterogeneity among Colombian populations correlates with the eco-epidemiological and morphological traits observed in this species across regions within the country. Such genetic and epidemiological diversity should be taken into consideration for the development of vector control strategies and entomological surveillance. Copyright © 2013. Published by Elsevier B.V.
Full Text Available Triatoma nitida was found in 14 (0.4% out of 3,726 houses located in six departments across Guatemala, which were surveyed from 1994 to 1998 by the man-hour collection method. Compared to previous information, the distribution of T. nitida in Guatemala has increased from five to nine departments; the species is present in mild climates at altitudes from 960 to 1,500 m. Fourteen percent of the intradomestic T. nitida were infected with Trypanosoma cruzi. The species was often found in conjunction with other triatomines (T. dimidiata and Rhodnius prolixus. The domestic and peridomestic presence of T. nitida in Guatemala was rare, but occasionally this species was colonizing human-made constructions. T. nitida appears to have a low importance as Chagas disease vector in Guatemala, as indicated by its scarce presence in the domestic habitats and defecation patterns. However, it clearly has potential to become a Chagas vector so we recommend an on-going study of the intradomestic presence of T. nitida following the control programs in Guatemala. Morphometric analysis of 47 T. nitida males from three localities showed quantitative differences between the populations, which indicates that geographic distance is an important factor in the structuring of T. nitida populations.
Gonçalves, Teresa Cristina Monte; Teves-Neves, Simone Caldas; dos Santos-Mallet, Jacenir Reis; Carbajal-de-la-Fuente, Ana Laura; Lopes, Catarina Macedo
Triatoma jatai sp. nov. is the first new species of triatomine to be described in the state of Tocantins, in the northern region of Brazil. It was caught on rock outcrops in the wild environment and, more recently, invading homes. While T. jatai sp. nov. is morphologically similar to Triatoma costalimai, it is distinguished by its general colouring, differences in the blotches on the connexivum, wing size in females and external structures of the male genitalia. The type series has been deposited in the Entomological Collection and Herman Lent Collection, Oswaldo Cruz Institute-Oswaldo Cruz Foundation, Rio de Janeiro, Brazil. PMID:23828010
Full Text Available Se propone para R. prolixus un mecanismo antidiurético, cuya actividad se pone de manifiesto una vez transcurrido el periodo diurético y se mantiene hasta que el insecto es alimentado nuevamente. Presumiblemente este mecanismo actua a nivel del esfinter rectal proximal y es inhibido por la ingesta, distención mecanica del buche y desinhibición central por decapitación. Se sugiere que la actividad antidiurética es mantenida por vía nerviosa y se modifica cuando hay distensión del buche o canudo es interrumpida la senãl nerviosa por decapitación. Se pone de manifiesto que la excreción de orina en R. prolixus no es controlada exclusivamente por la hormona diurética, sino que factores no ligados a la hemolinfa mantienen en estado diurético y no diurético a los insectos.An antidiuretic mechanism is proposed for Rhodnius prolixus, whose activity is manifested when the diuretic phase has terminated and is maintained until the insect has fed again. Presumably this mechanism acts at the level of the proximal rectal sphincter and is inhibited by ingestion, mechanical distension of the gut and central desinhibition by decapitation. It is suggested that the antidiuretic activity is maintained by the nervous system and is modified when there is distention of the gut or when the nervous signal is interrupted by decapitacion. It is demonstrated that the excretion of urine in R. prolixus is not controlled exclusively by the diuretic hormone, but rather that factors not linked to the haemolvmph maintain the insects in a diuretic or nondiuretic state.
Conclusiones. Los resultados evidenciaron diferencias en la diversidad de las dos regiones, además del potencial de las especies silvestres para ocupar ecótopos artificiales. La intrusión de triatominos y la reciente incriminación de especies silvestres en la transmisión de Trypanosoma cruzi, indican la necesidad de un mayor conocimiento de la ecología de estos vectores para orientar las estrategias de control.
Carcavallo, Rodolfo U.; Barata, José M. S.; Costa, Antônio I. P. da; Serra, Oswaldo P.
Sobre Alberprosenia malheiroi n. sp. deu-se a conhecer uma diagnose resumida em 1980, porém sem valor bibliográfico. Em 1987 publicou-se a mesma diagnose anexando uma foto e alguns comentários, porém sem realizar uma descrição formal. Descreve-se para esta espécie, os adultos, os estádios imaturos, determina-se a série sintípica e apresenta-se dados bionômicos e de criação em insetário. As diferenças mais evidentes com A. goyovargasi, a única espécie que se conhecia do gênero até então, são a...
Abad-Franch, Fernando; Pavan, Márcio G; Jaramillo-O, Nicolás; Palomeque, Francisco S; Dale, Carolina; Chaverra, Duverney; Monteiro, Fernando A
Rhodnius barretti , a new triatomine species, is described based on adult specimens collected in rainforest environments within the Napo ecoregion of western Amazonia (Colombia and Ecuador). R. barretti resembles Rhodnius robustus s.l. , but mitochondrial cytochrome b gene sequences reveal that it is a strongly divergent member of the “robustus lineage”, i.e., basal to the clade encompassing Rhodnius nasutus , Rhodnius neglectus , Rhodnius prolixus and five members of the R. robustus species complex. Morphometric analyses also reveal consistent divergence from R. robustus s.l. , including head and, as previously shown, wing shape and the length ratios of some anatomical structures. R. barretti occurs, often at high densities, in Attalea butyracea and Oenocarpus bataua palms. It is strikingly aggressive and adults may invade houses flying from peridomestic palms. R. barretti must therefore be regarded as a potential Trypanosoma cruzi vector in the Napo ecoregion, where Chagas disease is endemic. PMID:24473808
Obara, Marcos T; da Rosa, João A; da Silva, Nilza N; Ceretti, Walter; Urbinatti, Paulo R; Barata, José M S; Jurberg, José; Galvão, Cleber
The objective of this study was to analyze the morphological and histological characteristics of eggs from six triatomine species in order to obtain a generic and specific characterization of this group of Trypanosoma cruzi vectors and better understand their phylogenetic and taxonomic aspects. The eggs of the respective species came from the collection of the Laboratório de Triatomíneos e Culicídeos da Faculdade de Saúde Pública/USP, from the Insetário do Serviço Especial de Saúde de Araraquara - SESA and from the Triatomine insectary of the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos (FIOCRUZ), in Rio de Janeiro. Morphological studies were done with optical microscopy and scanning electron microscopy. Histological analyses used only optical microscopy. All of the species analyzed showed a predominance of hexagonal cells. The exchorion of Triatoma breyeri Del Ponte, T. costalimai Verano Galvão, and T. tibiamaculata (Pinto) consists of unornamented cells, overlapping or slightly separated, with a smooth, padded appearance. Meanwhile, in T. matogrossensis Leite Barbosa, T. sherlocki Papa, Juberg, Carcavallo, Cerqueira Barata, and T. williami Galvão, Souza Lima, the exchorion cells are ornamented on their entire surface with perforations and fissures. Egg histology showed undulations, pores, and orifices. The study helps to expand the generic and specific knowledge of the Triatominae subfamily. The characteristics identified in the exchorion of the eggshells can help separate close species. These new parameters will back the elaboration of future dichotomous keys, help to determine each vector species role and expand knowledge of the various species.
Patricia de Azambuja
Full Text Available Precocene II, added to the meal of fourth-instar larvae of Rhodnius prolixus (25 mug/ml of blood, induced an in crease in the duration of the molting cycle. This effect was related to the decrease of both the nuclear area of the prothoracic gland cells and the mitotic activity in epidermal cellS. juvenile hormone analogue applied topically (60 mug/insect together with Precocene II treatment avoided atrophy of the prothoracic glands and induced a higher number of epidermal mitosis accelerating the time of subsequent ecdysis. A possible relationship between juvenile hormone and production of ecdysone is discussed.Adicionado ao sangue alimentar na dose de 25 mug/ml o precoceno II causou um aumento no período de intermuda em ninfas de 4o. estadio de Rhodnius prolixus. Este atraso da muda foi relacionado com a diminuição da área dos núcleos das celulas das glandulas protoracicas e com a queda da atividade mitotica das células da epiderme do inseto. Um análogo de hormônio juvenil aplicado topicamente (60 mug/inseto junto com o tratamento oral com precoceno II preveniu a atrofia das glândulas protorácicas e induziu um aumento no número de mitoses nas células da epiderme, diminuindo o período de intermuda nestes insetos.A possivel relação entre a ação do hormônio juvenil e a producao de ecdisona pelas glândulas protorácicas e discutida.
Braga, M V; Pinto, Z T; Lima, M M
The life cycle and reproductive patterns of Triatoma rubrofasciata were studied along with laboratory conditions for the establishment of a prolific colony. The insects were divided into four groups: two of them were maintained at room temperature (20.5 degrees C to 33 degrees C and 85% +/- 5% of relative humidity), the other two in a climatic chamber (CC) (temperature: 29 degrees C, humidity: 80% +/- 5%). The groups were fed weekly or fortnightly on Swiss mice. The females from the group kept in the CC and fed weekly had longer life span, as well as a higher number of eggs, fertile eggs and hatchings; the group kept in the CC and fed fortnightly had a shorter life span for the 1st, 2nd and 3rd instars and a lower mortality rate for all instars. It was concluded that a constant high temperature (CC at 29 degrees C) is the most suitable condition for the maintenance of a colony of T. rubrofasciata regardless of the interval between repasts.
Nicolás J. Schweigmann
Full Text Available This paper compares the predation pressure that ducks and chickens exert on triatomines. For the tests, these birds were placed in individual boxes together with a known number of Triatoma infestans and left to interact from 6 p.m. till the next morning, involving a long lasting period of complete darkness limited by two short-term periods of semi-darkness. There was a shelter which could prevent the bugs from being predated. The number of live and dead triatomines was recorded, considering missing bugs as predated by the birds. Ducks exhibited a greater predatory activity than chickens, that could be due to a long term active period at night while chickens sleep motionless from sunset to dawn. Surviving triatomines that had fed on chickens outnumbered those fed on ducks suggesting that these were less accessible to the triatomine biting. If ducks are better than chickens to detect and eat bugs and to interfere with their feeding in the field, an increase in duck number might help to diminish triatomine density. Further research is needed to determine the feasibility of application of these experimental results.
Grasielle Caldas D`avila Pessoa
Full Text Available INTRODUCTION: Despite years of efforts towards the elimination of Triatoma infestans in Brazil, residual foci still persist in some areas of the States of Bahia and Rio Grande do Sul. The persistence of these T. infestans populations in the country has two different origins of equal concern: operational failures or insecticide resistance. Thus, the objective of this study was to characterize the susceptibility profile of the residual Brazilian populations of T. infestans to deltamethrin. METHODS: The susceptibility reference lineage was derived from Cipein/Argentina. The populations studied were manually collected using a dislodging agent in peridomiciles in the States of Bahia (Novo Horizonte and of Rio Grande do Sul (Santa Rosa and Doutor Maurício Cardoso. Serial dilutions of deltamethrin were prepared and applied at the dorsal abdomen of first instar nymphs. The control group received only pure acetone. Mortality was evaluated after 72h. Qualitative tests assessed the mortality of a diagnostic dose of 1xLD99 (2.76ng a.i./nymph determined for the susceptibility reference lineage. RESULTS: The susceptibility profile characterization of the T. infestans populations revealed an RR50 ranging from 1.73 to 3.26. The mortality percentage in response to a diagnostic dose was 100%. The results obtained in the quantitative and qualitative assays corresponded for all populations. CONCLUSIONS: The results of this study indicate that the persistence of residual foci of T. infestans in Bahia and Rio Grande do Sul is not related to insecticide resistance but may be associated with operational failures. In Rio Grande do Sul, we must consider the possibility of continuous reinfestation by Argentinian individuals, which justifies active and efficient epidemiological surveillance.
Ramsey, Janine M; Peterson, A Townsend; Carmona-Castro, Oscar; Moo-Llanes, David A; Nakazawa, Yoshinori; Butrick, Morgan; Tun-Ku, Ezequiel; de la Cruz-Félix, Keynes; Ibarra-Cerdeña, Carlos N
Chagas disease is one of the most important yet neglected parasitic diseases in Mexico and is transmitted by Triatominae. Nineteen of the 31 Mexican triatomine species have been consistently found to invade human houses and all have been found to be naturally infected with Trypanosoma cruzi. The present paper aims to produce a state-of-knowledge atlas of Mexican triatomines and analyse their geographic associations with T. cruzi, human demographics and landscape modification. Ecological niche models (ENMs) were constructed for the 19 species with more than 10 records in North America, as well as for T. cruzi. The 2010 Mexican national census and the 2007 National Forestry Inventory were used to analyse overlap patterns with ENMs. Niche breadth was greatest in species from the semiarid Nearctic Region, whereas species richness was associated with topographic heterogeneity in the Neotropical Region, particularly along the Pacific Coast. Three species, Triatoma longipennis, Triatoma mexicana and Triatoma barberi, overlapped with the greatest numbers of human communities, but these communities had the lowest rural/urban population ratios. Triatomine vectors have urbanised in most regions, demonstrating a high tolerance to human-modified habitats and broadened historical ranges, exposing more than 88% of the Mexican population and leaving few areas in Mexico without the potential for T. cruzi transmission. PMID:25993505
Ângela Pinheiro Carneiro
Full Text Available The use of synthetic insecticides for insect control may lead to different kind of problems, such as vector resistance to insecticides. To avoid these problems, a new research area to study botanical products as possible disease vectors controls, has become a feasible alternative. The purpose of this research was to evaluate the biocide activity of the ethanol extract of seeds of Annona coriacea on Rhodnius neglectus (Chagas disease vector nymphs and adults. For this, different concentrations extracts were evaluated: 25, 50, 100 and 200mg/ mL, and water in DMSO (20% was used as control. The experimental design was completely randomized and we conducted the bioassay with nymphs and adults, with 10 nymphs and 10 adults (five males and five females per treatment. Extract action was evaluated in both bioassays, in order to identify possible effects of mortality and life cycle interruption of nymphs and adults during a 28-day-period. The results obtained showed that the extract of A. coriacea was able to disrupt the development of nymphs and adults of R. neglectus, with a mortality rate of more than 90%, 36% and 100%, at the highest concentrations, respectively. There was also molting inhibition in nymphs, lower reproductive capacity in females, feeding deterrence and morphological changes in nymphs and adults. We concluded that the extract of A. coriacea has insecticide action on nymphs and adults of R. neglectus.La enfermedad de Chagas se convirtió en un problema de salud debido a su importancia epidemiológica, es producida por el protista Trypanosoma cruzi, cuyos insectos vectores son del género Triatoma y Panstrongylus. El objetivo de este estudio fue evaluar la actividad biocida del extracto de Annona coriacea en las ninfas de Rhodnius neglectus y en sus adultos. Se evaluaron 14 concentraciones de 25, 50, 100 y 200mg/ml del extracto etanólico, así como el control, en este caso agua de DMSO (20%. Se utilizo un diseño completamente aleatorizado con tres repeticiones para el bioensayo con 10 ninfas y 10 adultos (cinco machos y cinco hembras para cada tratamiento. La acción del extracto se observo durante 28 días en ambos bioensayos. Los resultados obtenidos mostraron que el extracto de A. coriacea fue capaz de interrumpir el desarrollo de las ninfas y adultos de R. neglectus, con una mortalidad de más del 90%, 36% y 100%, correspondiendo a las concentraciones más altas. También hubo inhibición de la muda de las ninfas, una menor capacidad reproductiva de las hembras, disuasión alimentaria y cambios morfológicos en las ninfas y adultos. Se concluye que el extracto de A. coriacea presentó acción insecticida en ninfas y adultos de R. neglectus.
Gurgel-Goncalves, Rodrigo; Cuba, César Augusto Cuba
Rhodnius neglectus is frequently found in palm trees and bird nests in sylvatic environments. However, adult specimens infected by Trypanosoma cruzi have been invading houses in central Brazil. Analyzing and predicting the geographical distribution of this species may improve vector surveillance strategies for Chagas disease. Ecological niche modeling using the genetic algorithm for rule-set production (GARP) was applied to predict the geographical distribution of R. neglectus from occurrence records and a set of 23 predictor variables (e.g., temperature, precipitation, altitude, and vegetation). Additionally, the geographical distribution of R. neglectus was compared with the geographical distribution of four species of palm trees and two species of birds from the study region. The models were able to predict, with high probability, the occurrence of R. neglectus as a regular (although nonendemic) species of the Cerrado biome in central Brazil. Caatinga, Amazonian savanna, Pantanal, and the Bolivian Chaco appear as areas with lower probabilities of potential occurrence for the species. A great overlap was observed between the distribution of R. neglectus, palm trees (Acrocomia aculeata and Syagrus oleracea), and birds (Phacellodomus ruber and Pseudoseisura cristata). By including new records for R. neglectus (from both sylvatic and domestic environments), our study showed a distribution increase toward the west and northeast areas of Brazil in the "diagonal of open/dry ecoregions of South America". These results should aid Chagas disease vector surveillance programs, given that household invasion by Rhodnius species maintains the risk of disease transmission and limits control strategies.
Ramsey, Janine M; Peterson, A Townsend; Carmona-Castro, Oscar; Moo-Llanes, David A; Nakazawa, Yoshinori; Butrick, Morgan; Tun-Ku, Ezequiel; la Cruz-Félix, Keynes de; Ibarra-Cerdeña, Carlos N
Chagas disease is one of the most important yet neglected parasitic diseases in Mexico and is transmitted by Triatominae. Nineteen of the 31 Mexican triatomine species have been consistently found to invade human houses and all have been found to be naturally infected with Trypanosoma cruzi. The present paper aims to produce a state-of-knowledge atlas of Mexican triatomines and analyse their geographic associations with T. cruzi, human demographics and landscape modification. Ecological niche models (ENMs) were constructed for the 19 species with more than 10 records in North America, as well as for T. cruzi. The 2010 Mexican national census and the 2007 National Forestry Inventory were used to analyse overlap patterns with ENMs. Niche breadth was greatest in species from the semiarid Nearctic Region, whereas species richness was associated with topographic heterogeneity in the Neotropical Region, particularly along the Pacific Coast. Three species, Triatoma longipennis, Triatoma mexicana and Triatoma barberi, overlapped with the greatest numbers of human communities, but these communities had the lowest rural/urban population ratios. Triatomine vectors have urbanised in most regions, demonstrating a high tolerance to human-modified habitats and broadened historical ranges, exposing more than 88% of the Mexican population and leaving few areas in Mexico without the potential for T. cruzi transmission.
Souza, Eder dos Santos; Von Atzingen, Noé Carlos Barbosa; Furtado, Maria Betânia; de Oliveira, Jader; Nascimento, Juliana Damieli; Vendrami, Daniel Pagotto; Gardim, Sueli; da Rosa, João Aristeu
Abstract Rhodnius marabaensis sp. n. was collected on 12 May 2014 in the Murumurú Environmental Reserve in the city of Marabá, Pará State, Brazil. This study was based on previous consultation of morphological descriptions of 19 Rhodnius species and compared to the identification key for the genus Rhodnius. The examination included specimens from 18 Rhodnius species held in the Brazilian National and International Triatomine Taxonomy Reference Laboratory in the Oswaldo Cruz Institute in Rio de Janeiro, Brazil. The morphological characteristics of the head, thorax, abdomen, genitalia, and eggs have been determined. Rhodnius prolixus and Rhodnius robustus were examined in more detail because the BLAST analysis of a cyt-b sequence shows they are closely related to the new species, which also occurs in the northern region of Brazil. The most notable morphological features that distinguish Rhodnius marabaensis sp. n. are the keel-shaped apex of the head, the length of the second segment of the antennae, the shapes of the prosternum, mesosternum and metasternum, the set of spots on the abdomen, the male genitalia, the posterior and ventral surfaces of the external female genitalia, and the morphological characteristics of the eggs. Rhodnius jacundaensis Serra, Serra & Von Atzingen (1980) nomen nudum specimens deposited at the Maraba Cultural Center Foundation - MCCF were examined and considered as a synonym of Rhodnius marabaensis sp. n. PMID:27833419
Parra-Henao, Gabriel; Suárez-Escudero, Laura C; González-Caro, Sebastián
Ecological niche modeling of Triatominae bugs allow us to establish the local risk of transmission of the parasite Trypanosoma cruzi, which causes Chagas disease. This information could help to guide health authority recommendations on infection monitoring, prevention, and control. In this study, we estimated the geographic distribution of triatomine species in Colombia and identified the relationship between landscape structure and climatic factors influencing their occurrence. A total of 2451 records of 4 triatomine species ( Panstrongylus geniculatus , Rhodnius pallescens , R. prolixus , and Triatoma maculata ) were analyzed. The variables that provided more information to explain the ecologic niche of these vectors were related to precipitation, altitude, and temperature. We found that the species with the broadest potential geographic distribution were P. geniculatus , R. pallescens , and R. prolixus . In general, the models predicted the highest occurrence probability of these vectors in the eastern slope of the Eastern Cordillera, the southern region of the Magdalena valley, and the Sierra Nevada of Santa Marta.
Costa, J; Freitas-Sibajev, M G; Marchon-Silva, V; Pires, M Q; Pacheco, R S
Triatoma brasiliensis is one of the most important vectors of Chagas disease in the semiarid zone of the northeast of Brazil. Intraspecific morphological and behavioural variation has been reported for different populations. Results for four distinct populations using eight isoenzymes are reported here. The literature describes three subspecies: T. brasiliensis brasiliensis Neiva, 1911; T. brasiliensis melanica Neiva & Lent, 1941 and T. brasiliensis macromelasoma Galvão, 1956. These subspecies differ mainly in their cuticle colour pattern and were regarded as synonyms by Lent and Wygodzinsky (1979). In order to evaluate whether the chromatic pattern is a morphological variation of different melanic forms within T. brasiliensis or due to interspecific variation, field collections were performed in localities where these three subspecies have been described: Caicó (Rio Grande do Norte), the type-locality for T. b. brasiliensis; Petrolina (Pernambuco) for T. b. macromelasoma and Espinosa (Minas Gerais) for T. b. melanica. A fourth distinct chromatic pattern was found in Juazeiro (Bahia). A total of nine loci were studied. Values of Nei's genetic distance (D) were calculated. T. b. brasiliensis and T. b. macromelasoma are the closest populations with a D = 0.295. T. b. melanica had a D > or = 0.537 when compared to the others, a distance in the range of interspecific variation for other triatomine species.
Triatoma brasiliensis Neiva, 1911 is now considered the most important Chagas disease vector in the semiarid zones of northeastern Brazil. Four distinct populations of T. brasiliensis have been identified by multidisciplinary studies: brasiliensis (Caicó, RN), melânica (Espinosa, MG), macromelasoma (Petrolina, PE), and juazeiro (Juazeiro, BA). By scanning electron microscopy of egg exochorion, each population displayed a distinct ornamentation pattern. The brasiliensis, macromelasoma, and juazeiro populations were found in both artificial ecotopes and the wild, while the mel anica population was collected only in the wild. Isoenzymatic analysis detected phenotypic and genetic differences among them, with the melânica population being the most distinct. The brasiliensis population is the most important one from an epidemiological point of view, with the widest geographic distribution, the highest Trypanosoma cruzi infection rate, and occupying a wide variety of ecotopes.
Costa, J; de Almeida, J R; Britto, C; Duarte, R; Marchon-Silva, V; Pacheco, R da S
Triatoma brasiliensis is considered as one of the most important Chagas disease vectors in the northeastern Brazil. This species presents chromatic variations which led to descriptions of subspecies, synonymized by Lent and Wygodzinsky (1979). In order to broaden bionomic knowledge of these distinct colour patterns of T. brasiliensis, captures were performed at different sites, where the chromatic patterns were described: Caicó, Rio Grande do Norte (T. brasiliensis brasiliensis Neiva, 1911), it will be called the "brasiliensis population"; Espinosa, Minas Gerais (T. brasiliensis melanica Neiva & Lent 1941), the "melanica population" and Petrolina, Pernambuco (T. brasiliensis macromelasoma, Galvão 1956), the "macromelasoma population". A fourth chromatic pattern was collected in Juazeiro, Bahia the darker one in overall cuticle coloration, the "Juazeiro population". At the sites of Caicó, Petrolina and Juazeiro, specimens were captured in peridomiciliar ecotopes and in wilderness. In Espinosa the specimens were collected only in wilderness, even though several exhaustive captures have been performed in peridomicile at different sites of this municipality. A total of 298 specimens were captured. The average registered infection rate was 15% for "brasiliensis population" and of 6.6% for "melanica population". Specimens of "macromelasoma" and of "Juazeiro populations" did not present natural infection. Concerning trophic resources, evaluated by the precipitin test, feeding eclecticism for the different colour patterns studied was observed, with dominance of goat blood in household surroundings as well as in wilderness.
Full Text Available Sete espécies da tribo bolboderini, pertencentes aos gêneros Bolbodera, Belminus, Microtriatoma e Parabelminus, duas das quais já encontradas naturalmente infectadas com Trypanosoma cruzi, foram analisadas e comparadas tendo como enfoque oito estruturas da genitália externa dos machos: Processo mediano do pigóforo (PrP, Processo da conjuntiva (PrCj, Extensão mediana da placa basal (EPIb, Processo do endosoma (PrEn, Suporte do falosoma (SPh, Falosoma (Ph, Processo do gonoporo (PrG e a Vesica (V. Microtriatoma trinidadensis (lent, 1951 e M. borbai Lent & Wygodzinsky, 1979 mostraram um plano estrutural morfológico semelhante a Parabelminus yurupucu Lent & Wygodzinsky, 1979 e P. carioca Lent, 1943 e deferindo nitidamente de Belminus peruvianus Herrer, Lent & Wygodzinsky, 1954 e B. herreri Lent & Wygodzinsky, 1979 e de Bolbodera scabrosa, Valdés, 1910, não só pela ausência como pela forma de determinadas estruturas. Estas observações comparativas confirmam as afinidades entre Microtriatoma e Parabelminus e suas relações com belminus e Bolbodera.Seven species of the Bolboderini tribe belonging to the genera bolbodera, Belminus, Microtriatoma and Parabelminus, two of them found naturally infected with Trypanosoma cruzi, were analysed and compared emphasizing eight structures of the male external genitalia: median process of pygophore (PrP, conjunctiva process (PrCj, pedicel (EP1b, endosoma process (PrEn, struts (SPh, phallosoma (Ph, medium bridge (PrG and vesica (V. Microtriatoma trinidadensis (Lent, 1951 and M. borbai Lent & Wygodzinsky, 1979 have shown a structural morphological aspect similar to Parabelminus yurupucu Lent & Wygodzinsky, 1979 and P. carioca Lent, 1943 differing clearly from Belminus peruvianus Herrer, Lent & Wygodzinsky, 1954, B. herreri Lent & Wygodzinsky, 1979 and Bolbodera scabrosa valdés, 1910, not only by the absence but by the shape of some structures. These comparative observations confirm the affinity between Microtriatoma and Parabelminus and their relations with Belminus and Bolbodera.
Moretti, A N; Seccacini, E A; Zerba, E N; Canale, D; Alzogaray, R A
Monoterpenes are the main components of essential oils. Some members of this chemical family present insecticidal activity. Triatoma infestans (Klug) is the main vector of Chagas disease in Argentina, Bolivia, Paraguay, and Perú. The objective of this work was to evaluate the effect of six monoterpenes (1,8-cineole, eugenol, linalool, menthol, α-terpineol, and thymol) on the locomotor and flushing out activity of T. infestans. A video tracking technique was used to evaluate the locomotor activity of nymphs exposed to different concentrations of these chemicals applied as films on filter paper. Papers treated with acetone alone were used as negative controls, while solutions of tetramethrin were applied as positive controls. Only linalool and menthol produced hyperactivation. Flushing out was assessed under laboratory conditions using a standardized aerosolization method. All monoterpenes were applied at 1.5 g/m3. 1,8-Cineole, α-terpineol, and thymol flushed out 10% or less nymphs. The average flushing out produced by eugenol was 36.7%. Values of median flushing out time (FT50) could only be calculated for linalool and menthol (16.67 and 42.98 min, respectively). The FT50 value for the positive control tetramethrin (applied at 0.006 g/m3) was 8.29 min. Following these results, the flushing out activity of a mixture of linalool and eugenol was evaluated. The FT50 of this 2:1 linalool:eugenol mixture was 40.73 min. Finally, flushing out assays performed in semifield conditions showed similar results to those obtained at the laboratory. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Farfán-García, Ana E; Angulo-Silva, Víctor M
Determining Triatoma dimidiata's feeding behaviour in domiciliary and extra-domiciliary habitats in an endemic area of the Santander department in Colombia. The ELISA technique was used for processing the intestinal contents of 367 insects captured in rural areas around the municipalities of Capitanejo and Macaravita. 12 anti-animal species specific polyclonal anti-sera were used in ELISA. T. dimidiata hosts were determined by reactivity to each anti-serum; host percentages were established. 42.2% of the intestinal content processed by ELISA was reactive for blood proteins from one or more than 10 hosts. Domestic animal proteins were identified in all reactive intra-domiciliary and peridomestic insects, most often chicken blood, followed by that from goats, canines and humans. Blood from domestic animals like goats, chicken and horses was also detected in wild insects. Blood from animals such as armadillo and fara were identified in intra-domiciliary insects. Human host protein was found in 11% of intra-domiciliary and peri-domiciliary insects. The vector's eclectic nature in domiciliary and extra-domiciliary habitats was determined by identifying human blood in wild and domestic animals. The wild populations' mobility towards domiciliary and peri-domiciliary areas was demonstrated by finding domestic animals' blood in them and wild animals' blood in domestic and peri-domestic insects. These results contribute towards understanding Trypanosoma cruzi transmission-cycles.
Suárez-Escudero, Laura C.; González-Caro, Sebastián
Ecological niche modeling of Triatominae bugs allow us to establish the local risk of transmission of the parasite Trypanosoma cruzi, which causes Chagas disease. This information could help to guide health authority recommendations on infection monitoring, prevention, and control. In this study, we estimated the geographic distribution of triatomine species in Colombia and identified the relationship between landscape structure and climatic factors influencing their occurrence. A total of 2451 records of 4 triatomine species (Panstrongylus geniculatus, Rhodnius pallescens, R. prolixus, and Triatoma maculata) were analyzed. The variables that provided more information to explain the ecologic niche of these vectors were related to precipitation, altitude, and temperature. We found that the species with the broadest potential geographic distribution were P. geniculatus, R. pallescens, and R. prolixus. In general, the models predicted the highest occurrence probability of these vectors in the eastern slope of the Eastern Cordillera, the southern region of the Magdalena valley, and the Sierra Nevada of Santa Marta. PMID:28115946
Alevi, Kaio Cesar Chaboli; Borsatto, Kelly Cristine; Moreira, Felipe Ferraz Figueiredo; Jurberg, José; De Azeredo-Oliveir, Maria Tercília Vilela
Triatoma rubrofasciata (De Geer) is the first species of triatomine described, and little is known on its vector biology. Studies are restricted to starvation resistance, interspecific morphometric variability, morphometry of testis follicles, coloration of the testicular peritoneal sheath, ultrastructure of the male accessory glands, phylogeny and cytogenetics. Thus, this study aims to address the karyosystematics of T. rubrofasciata and the possible events related to karyotype evolution of this species. Four adult males were analyzed cytogenetically. The analysis of meiotic metaphases of T. rubrofasciata allowed to confirm the karyotype of species, out more, 2n = 25 (22A + X1X2Y). This number is very important for taxonomic and evolutionary inferences on the species, because of the 88 triatomine species with described karyotype, only T. rubrofasciata exhibits 25 chromosomes. Based on the hypothesis of the karyotype 2n = 22 (20A + XY) as ancestral for triatomines, we propose three evolutionary hypotheses for the emergence of the karyotype of T rubrofasciata, all supported by agmatoploidy events (fission). Basically the hypotheses are 1) fission for a pair of autosomes, resulting in 22 autosomes and later fission of sex chromosome X; 2) fission of pair of autosomes and the sex chromosome X concomitantly; 3) fission of sex chromosome X and subsequently fission of pair of autosomes. Thus, this study highlights for the first time the importance of the number of chromosomes of T. rubrofasciata as characteristic diagnosis in Triatominae subfamily and describes three evolutionary hypotheses that possibly led the emergence of karyotype of this insect of global importance.
da Rosa, João Aristeu; Souza, Eder Santos; da Costa Teixeira, Adelson; Barbosa, Rosenildo Ribeiro; de Souza, Aecildo José; Belintani, Tiago; Nascimento, Juliana Damieli; Gil-Santana, Hélcio Reinaldo; de Oliveira, Jader
Rhodnius amazonicus Almeida et al. (1973) is a triatomine of rare occurrence. This species was found for the third time in Breves city, Pará state, Brazil. Morphometric and morphological studies were carried out on one male and one female. Lent and Wygodzinsky (1979) considered this species as a synonym of R. pictipes, until its revalidation after 23 years by Bérenger and Pluot-Sigwalt (2002). Considering the synonym mentioned above, a comparative study between these two species was performed in order to report the third encounter of this species, and increase the number of morphological characters that distinguish R. amazonicus from R. pictipes. The dorsal side of the head, the dorsal and ventral portions of the thorax, the dorsal, ventral and posterior sides of the female genitalia, eggs and the median process of the pygophore were examined by scanning electronic microscopy (SEM). The head, thorax, abdomen and egg parameters of these two species were also measured. The identification of characters on the head, stridulatory sulcus, mesosternum, metasternum, scutellum, process of urotergite I, external female genitalia, pygophore and eggs made the distinction between R. amazonicus and R. pictipes possible. This study has shown the new characters recorded and described for the first time for R. amazonicus and R. pictipes by SEM here made it possible to confirm the morphological separation between these two species. The morphometric analysis also confirmed that the above two taxa are different at specific level. Copyright © 2017. Published by Elsevier B.V.
Alevi, Kaio C C; Rosa, João A; Azeredo-Oliveira, Maria Tercília V
We analyzed the classical cytotaxonomy of the Brasiliensis subcomplex (Triatoma brasiliensis Neiva, T. juazeirensis Costa & Felix, T. melanica Costa, Argolo & Felix, T. melanocephala Neiva & Pinto, T. petrochiae Pinto & Barreto, T. lenti Sherlock & Serafim, T. sherlocki Papa, Jurberg, Carcavallo, Cerqueira & Barata, T. tibiamaculata Pinto and T. vitticeps Stal) and the T. brasiliensis complex (T. b. brasiliensis, T. b. macromelasoma Neiva & Lent, T. juazeirensis, T. melanica and T. sherlocki). The five members of the T. brasiliensis complex share the same cytogenetic characteristics. Merely T. sherlocki show differences in spermatids, which confirms the status of more differentiated member of the complex. T. lenti also presented the same cytogenetic characteristics described for the species of the T. brasiliensis complex, which supports possible grouping of the species as sixth member of the complex, although further analysis as molecular and experimental crosses are needed to corroborate this hypothesis. T. petrochiae, T. vitticeps, T. tibiamaculata and T. melanocephala presented one or more characteristics that allow questioning grouping in the proposed Brasiliensis subcomplex. Thus, we suggested that Brasiliensis subcomplex and T. brasiliensis complex should be constituted by the same triatomines (T. b. brasiliensis, T. b. macromelasoma, T. juazeirensis, T. melanica and T. sherlocki). However, we draw attention to T. lenti and suggest that although new analyzes should be performed, possibly this species is the sixth member of the T. brasiliensis complex.
Meneguetti, Dionatas Ulises de Oliveira; Tojal, Simone Delgado; Miranda, Pedro Raimundo Mathias de; Rosa, João Aristeu da; Camargo, Luis Marcelo Aranha
This paper reports, for the first time, the presence of Rhodnius montenegrensis in the State of Acre, Brazil. Two female R. montenegrensis were collected in a dwelling in the rural area of Rio Branco, Acre, Brazil. The occurrence of this species was confirmed, and the number of Triatominae species in the State of Acre increased from four to five. Further studies should be performed to reach a clearer understanding of the ecology of this arthropod, its possible role in transmitting Chagas' disease and rangeliosis, and its current geographical distribution in the region.
Martínez-Ibarra, José Alejandro; Ventura-Rodríguez, Luz Verónica; Meillon-Isais, Karla; Barajas-Martínez, Héctor; Alejandre-Aguilar, Ricardo; Lupercio-Coronel, Patricia; Rocha-Chávez, Gonzalo; Nogueda-Torres, Benjamín
The present work is a thorough investigation of the degree of reproductive isolation between Meccus mazzottii and Meccus longipennis, Meccus picturatus, Meccus pallidipennis and Meccus bassolsae, as well as between M. longipennis and M. picturatus. We examined fertility and segregation of morphological characteristics in two generations of hybrids derived from crosses between these species. The percentage of pairs with (fertile) offspring was highest in the set of crosses between M. longipennis and M. picturatus, and lowest between M. mazzottii and M. picturatus. Most first-generation (F1) individuals from crosses involving M. mazzottii were morphologically similar to this species, while only F1 x F1 progeny of parental crosses between M. mazzottii and M. longipennis had offspring second generation that looked like M. mazzottii. The results indicate that different degrees of reproductive isolation apparently exist among the species of the Phyllosoma complex examined in this study. The biological evidence obtained in this study does not support the proposal that M. longipennis and M. picturatus are full species. It could indicate on the contrary, that both could be considered as subspecies of a single polytypic species. On the other hand, biological evidence supports the proposal that M. mazzottii is a full species.
Rabinovich, Jorge Eduardo; Kitron, Uriel Dan; Obed, Yamila; Yoshioka, Miho; Gottdenker, Nicole; Chaves, Luis Fernando
Host use by vectors is important in understanding the transmission of zoonotic diseases, which can affect humans, wildlife and domestic animals. Here, a synthesis of host exploitation patterns by kissing-bugs, vectors of Chagas disease, is presented. For this synthesis, an extensive literature review restricted to feeding sources analysed by precipitin tests was conducted. Modern tools from community ecology and multivariate statistics were used to determine patterns of segregation in host use. Rather than innate preferences for host species, host use by kissing-bugs is influenced by the habitats they colonise. One of the major limitations of studies on kissing-bug foraging has been the exclusive focus on the dominant vector species. We propose that expanding foraging studies to consider the community of vectors will substantially increase the understanding of Chagas disease transmission ecology. Our results indicate that host accessibility is a major factor that shapes the blood-foraging patterns of kissing-bugs. Therefore, from an applied perspective, measures that are directed at disrupting the contact between humans and kissing-bugs, such as housing improvement, are among the most desirable strategies for Chagas disease control.
Martínez-Ibarra, José Alejandro; Grant-Guillén, Yunuen; Ventura-Rodríguez, Luz Verónica; Osorio-Pelayo, Paola Denisse; Macías-Amezcua, Michael Dassaejv; Meillón-Isáis, Karla; Alejandre-Aguilar, Ricardo; Rodríguez-Bataz, Elvia; Nogueda-Torres, Benjamín
The degree of reproductive isolation between Meccus phyllosomus and the remaining five species of the genus Meccus, as well as between Meccus bassolsae and Meccus pallidipennis, Meccus longipennis and Meccus picturatus, was examined. Fertility and the segregation of morphological characteristics were examined in two generations of hybrids from crosses between these species. The percentage of couples with offspring (fertile) was high in the vast majority of sets of crosses, with the exception of that between ♀M. phyllosomus and ♂Meccus mazzottii. In sets of crosses involving M. bassolsae specimens, no first-generation (F1) individuals were morphologically similar to M. bassolsae, but instead shared the morphology of the other parental species. A similar phenomenon was observed in most sets of crosses involving M. phyllosomus. These results indicated that different degrees of reproductive isolation exist among the species of Meccus involved in this study. The biological evidence obtained in this study does not support the proposal that M. bassolsae is a full species. It could indicate that, on the contrary, it should be considered a subspecies of a single polytypic species. The biological evidence does support the proposal that M. phyllosomus is a full species.
Pessoa, Grasielle Caldas D‘Ávila; de Sousa, Tais Nóbrega; Sonoda, Ivan Vieira; Diotaiuti, Liléia
Triatoma sordida is a species that transmits Trypanosoma cruzi to humans. In Brazil, T. sordida currently deserves special attention because of its wide distribution, tendency to invade domestic environments and vectorial competence. For the planning and execution of control protocols to be effective against Triatominae, they must consider its population structure. In this context, this study aimed to characterise the genetic variability of T. sordida populations collected in areas with persistent infestations from Minas Gerais, Brazil. Levels of genetic variation and population structure were determined in peridomestic T. sordida by sequencing a polymorphic region of the mitochondrial cytochrome b gene. Low nucleotide and haplotype diversity were observed for all 14 sampled areas; π values ranged from 0.002-0.006. Most obtained haplotypes occurred at low frequencies, and some were exclusive to only one of the studied populations. Interpopulation genetic diversity analysis revealed strong genetic structuring. Furthermore, the genetic variability of Brazilian populations is small compared to that of Argentinean and Bolivian specimens. The possible factors related to the reduced genetic variability and strong genetic structuring obtained for studied populations are discussed in this paper. PMID:27143491
Rivas, Nancy; Sánchez-Cordero, Victor; Camacho, Alejandro D; Alejandre-Aguilar, Ricardo
Triatomine classification is based on morphological characteristics. Studies have been conducted to improve their identification by observing many characteristics. However, there are problems of differentiating among highly interrelated species and new criteria are required. The purpose of this study was to determine the morphological differences in the external female genitalia of M. pallidipennis, M. longipennis, M. picturatus, M. bassolsae, M. mazzottii, and M. phyllosomus in order to distinguish among species using scanning electron microscopy. Observations were made of the dorsal, posterior, lateral, and ventral views of the female external genitalia for each species. In the six species we studied, relevant differences were observed in the dorsal view of the X segment, as well as the IX, VIII, and VII tergites. In the posterior and lateral view, the most visible differences were registered in the gonocoxite size of the segments VIII, IX, and X. Finally, in the ventral view of the VII sternite, differences among species were observed in the size of the inflection in the top and upper corner. Our results show that it was possible to differentiate among the triatominae species for each of the four views by using a scanning electron microscope to analyze morphological characteristics of the VII, VIII, IX, and X abdomen segments. © 2017 The Society for Vector Ecology.
Brenière, Simone Frédérique; Waleckx, Etienne; Magallón-Gastélum, Ezequiel; Bosseno, Marie-France; Hardy, Xavier; Ndo, Cyrille; Lozano-Kasten, Felipe; Barnabé, Christian; Kengne, Pierre
The originally wild species of the Meccus complex are important vectors of Chagas disease in Mexico. In West Mexico, Meccus longipennis plays an important epidemiological role. To understand the genetic structure of the domestic and wild populations of this species, a preliminary study with five polymorphic microsatellite loci was conducted. The population genetics analysis showed high structuring between peridomestic biotopes, with breeding subunits detected in a single peridomestic structure. In the wild environment, two genetic patterns were observed according to the biotope, possible breeding subunits in large rocky formations and a larger panmictic unit in agropastoral areas, suggesting considerable dispersal of bugs in this biotope. Moreover, the discovery of two foci of wild populations at the edge of Guadalajara city raises the question of new urban areas where the phenomenon of bug incursions into households could constitute a risk of transmission of Chagas disease. Copyright © 2011 Elsevier B.V. All rights reserved.
Pita, Sebastián; Lorite, Pedro; Vela, Jesús; Mora, Pablo; Palomeque, Teresa; Thi, Khoa Pham; Panzera, Francisco
The analysis of the chromosomal and genome evolution in organisms with holocentric chromosomes is restricted by the lack of primary constriction or centromere. An interesting group is the hemipteran subfamily Triatominae, vectors of Chagas disease, which affects around 6 to 7 million people worldwide. This group exhibits extensive variability in the number and chromosomal location of repeated sequences such as heterochromatin and ribosomal genes. This paper tries to reveal the significant differences of the repeated sequences among Triatoma species through the use of genomic DNA probes. We analysed the chromosomal distribution and evolution of repeated sequences in Triatoma species by genomic in situ hybridization (GISH) using genomic DNA probes from two North American Triatoma species. These genomic probes were hybridized both on their own chromosomes and on other Triatoma species from North and South America, with different amounts and chromosome location of C-heterochromatin. The results were compared with those previously described using South American Triatoma genomic probes. We observed two chromosomal hybridization patterns: (i) very intense hybridization signals concentrated on specific chromosomal regions or particular chromosomes; and (ii) lower intensity hybridization signals dispersed along all chromosomes. Self-GISH on T. rubrofasciata and T. dimidiata chromosomes presented strong hybridization signals on all C-heterochromatin regions. However, when we perform genomic cross-hybridizations, only strong signals are detected on the Y chromosome, leaving the C-heterochromatic autosomal regions unmarked. We confirm that repeated DNA of the Y chromosome is shared among Triatoma species and probably represents an ancestral character of the Triatomini tribe. On the contrary, autosomal heterochromatic regions are constituted by species-specific DNA repeats, most probably satDNA families, suggesting that Triatoma speciation involved the amplification of diverse types of autosomal repeats. Molecular characterization of principal repetitive DNAs seems to be an appropriate approach to infer evolutionary relationships in triatomines.
Full Text Available A female of Triatoma guazu Lent & Wygodzinsky, 1979, a rare species from which the allotype was recently described, was studied by scanning electronic microscopy and videomicroscope. Some structures of the head and the thorax are shown. Some of them could have taxonomic importance, as the oculo-ocellar region, the buccula, the anterolateral angle of the collar, the scutellum, wings and the stridulatory sulcus, which has an unusual lateral high rim
Martínez-Ibarra, José Alejandro; Alejandre-Aguilar, Ricardo; Paredes-González, Edgar; Martínez-Silva, Miguel Alejandro; Solorio-Cibrián, Miriam; Nogueda-Torres, Benjamín; Trujillo-Contreras, Francisco; Novelo-López, Mónica
Aspects related to hatching, lifetime, number of blood meals for molting, mortality, feeding time, and postfeeding defecation delay were evaluated and compared in each instar of three North American Triatominae: Triatoma gerstaeckeri, Triatoma lecticularia and Triatoma protracta, all of them fed on rabbits. No significant differences (p > 0.05) were found among the three species regarding mean hatching rate, which was close to 20 days. Egg-to-adult development times were significantly shorter (p < 0.05) for T. lecticularia. Number of blood meals for molting to next instar ranged from one to five for T. protracta, and from one to six for T. gerstaeckeri and T. lecticularia. Mortality rates were higher in younger nymphs of T. lecticularia and T. protracta, while rates in T. gerstaeckeri were higher in fifth-instar nymphs. Mean feeding time was longest in T. gerstaeckeri, followed by T. lecticularia. More than twice the number of T. gerstaeckeri nymphs completed the development process, if compared to the nymphs from the other two species. Defecation delay was less than 10 min for T. lecticularia, T. protracta and the youngest nymphs of T. gerstaeckeri. Results point out that these three species may be important potential vectors of Trypanosoma cruzi for human populations, in areas of Mexico where these species are currently present.
Teresa Cristina Monte Goncalves
Full Text Available Triatoma jatai sp. nov. is the first new species of triatomine to be described in the state of Tocantins, in the northern region of Brazil. It was caught on rock outcrops in the wild environment and, more recently, invading homes. While T. jatai sp. nov. is morphologically similar to Triatoma costalimai, it is distinguished by its general colouring, differences in the blotches on the connexivum, wing size in females and external structures of the male genitalia. The type series has been deposited in the Entomological Collection and Herman Lent Collection, Oswaldo Cruz Institute-Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
Full Text Available Triatoma brasiliensis is considered as one of the most important Chagas disease vectors in the northeastern Brazil. This species presents chromatic variations which led to descriptions of subspecies, synonymized by Lent and Wygodzinsky (1979. In order to broaden bionomic knowledge of these distinct colour patterns of T. brasiliensis, captures were performed at different sites, where the chromatic patterns were described: Caicó, Rio Grande do Norte (T. brasiliensis brasiliensis Neiva, 1911, it will be called the "brasiliensis population"; Espinosa, Minas Gerais (T. brasiliensis melanica Neiva & Lent 1941, the "melanica population" and Petrolina, Pernambuco (T. brasiliensis macromelasoma, Galvão 1956, the "macromelasoma population". A fourth chromatic pattern was collected in Juazeiro, Bahia the darker one in overall cuticle coloration, the "Juazeiro population". At the sites of Caicó, Petrolina and Juazeiro, specimens were captured in peridomiciliar ecotopes and in wilderness. In Espinosa the specimens were collected only in wilderness, even though several exhaustive captures have been performed in peridomicile at different sites of this municipality. A total of 298 specimens were captured. The average registered infection rate was 15% for "brasiliensis population" and of 6.6% for "melanica population". Specimens of "macromelasoma" and of "Juazeiro populations" did not present natural infection. Concerning trophic resources, evaluated by the precipitin test, feeding eclecticism for the different colour patterns studied was observed, with dominance of goat blood in household surroundings as well as in wilderness
Abad-Franch, Fernando; Pavan, Márcio G; Jaramillo-O, Nicolás; Palomeque, Francisco S; Dale, Carolina; Chaverra, Duverney; Monteiro, Fernando A
Rhodnius barretti, a new triatomine species, is described based on adult specimens collected in rainforest environments within the Napo ecoregion of western Amazonia (Colombia and Ecuador). R. barretti resembles Rhodnius robustus s.l., but mitochondrial cytochrome b gene sequences reveal that it is a strongly divergent member of the "robustus lineage", i.e., basal to the clade encompassing Rhodnius nasutus, Rhodnius neglectus, Rhodnius prolixus and five members of the R. robustus species complex. Morphometric analyses also reveal consistent divergence from R. robustus s.l., including head and, as previously shown, wing shape and the length ratios of some anatomical structures. R. barretti occurs, often at high densities, in Attalea butyracea and Oenocarpus bataua palms. It is strikingly aggressive and adults may invade houses flying from peridomestic palms. R. barretti must therefore be regarded as a potential Trypanosoma cruzi vector in the Napo ecoregion, where Chagas disease is endemic.
Abstract. Rhodnius robustus Larrousse, is a sylvatic species found in northern Brazil (Acre, Amazonas and Pará, Guyana, Bolivia, Colombia, Ecuador, Peru and Venezuela. This species has been found in and around the dwellings, have been data collection of this species naturally infected with Trypanossoma cruzi Chagas, Trypanossoma rangeli Tejera and mixed infections. From observations made in the laboratory, we evaluated the ability of flight, correlating this activity with the amount of ingested blood, sex and fasting period. Despite the high temperature (33º C, 26% of the insects flew suggesting the influence of intrinsic factors in flight capacity of R. robustus.
Bar María Esther
Full Text Available Several palms species provide an important habitat for triatomines and associate vertebrates in tropical America. The objective of this work is to identify the triatomine species living in the palms of rural areas in the Province of Corrientes, and to estimate the potential epidemiological risk they represent for the residents of nearby houses. The survey was carried out in a palm community in Colonia Laurel, Department San Roque, Province of Corrientes, Argentina. Samplings were performed in October, November and December 1998; January, February and March 1999; May and June 1999. Thirty palms: 27 (90% Butia yatay (Mart. Becc. and 3 Acrocomia aculeata (Jacq. Lodd ex Mart. were dissected. Triatoma sordida Stål 1859 was found in 96.2% of B. yatay and in all the A. aculeata palms. A total of 272 live T. sordida was collected; 36 of them (13.2% were found in bird nests in the frond and the remainder in other locations of the tree. The mean number of triatomines per palm was 9.6 (range 1-60, mode 2. T. sordida was collected during all the sampling months and all stages were present at all seasons. The highest population density was reached in spring and the lowest in autumn. Trypanosoma cruzi was detected in 38.5% in feces of 174 examined insects and identified as such, both by microscopical examination and PCR. This is the first finding of T. sordida populations in B. yatay, an endemic palm of South America distributed in southern Brazil, Uruguay and northeastern Argentina. The high infection prevalence found in this work suggests that T. sordida plays an essential role in the maintenance of the wild T. cruzi transmission cycle in northeastern Argentina.
Full Text Available Among the vectors of Chagas disease, Triatoma patagonica is a species in the process of adaptation to the human environment being recently registered in urban and suburban zones. However, its importance as a vector of Chagas disease is unknown. The aim of this work was to evaluate two aspects of vectorial competence: the feeding behaviour and the defaecation pattern. These processes were studied in females of T. patagonica fed ad libitum on a restrained pigeon. The results showed that the blood meal size was negatively correlated with the time of first defaecation (r = -0.42. The first defaecation was emitted before the first 10 min and defaecations during feeding were frequent. A total of 73% of females, defaecated during the first 30 min post-feeding. These results suggest that if this species subsequently colonizes the domicile, it would be capable of transmitting Trypanosoma cruzi.
Rojas Cortéz Mirko G
Full Text Available The present work aims at learning the period of resistance to starvation (molting/death of Triatoma rubrofasciata in different stages of development and the respective loss of weight until death. Eggs of specimens from the greater area of the city of São Luis in the State of Maranhão, Brazil, yielded approximately 300 nymphs. These nymphs were placed in labelled Borrel glasses, in which they were weekly fed on rats (Rattus norvegicus, until reaching the stage to be observed. The experiments were conducted in a climatic chamber regulated at 29 ± 1° C, 70% relative humidity and 12 hr photoperiod. The resistance to starvation increased according to the stage of development, except for adult bugs, whose results were similar to the 3rd stage nymphs. In all these development stages there was an abrupt loss of weight in the first week, followed by a gradual loss until death. Comparing this work with those of other authors, it was observed that T. rubrofasciata is among the less resistant triatomine species.
Daniel R Cabello
Full Text Available The period of resistance to starvation and the loss of weight until death of Rhodnius neivai in all stages of development were studied. Work was based on experiments conducted under controlled laboratory conditions. One hundred specimens of each nymphal instar were observed: 50 were fed on chicken and 50 on rabbit. Adult females and males were kept together and fed on each host. All bugs were weighed weekly until death. Laid eggs were collected weekly and observed during five weeks to obtain hatchability. Resistance to starvation was similar with both hosts and increased with the evolutionary stage, excepting the 5th nymphal instar and adults. With both hosts, loss of weight was abrupt in the first week and steady in the following weeks. In adults, on the first weeks after eating, there was little or no mortality, after which mortality increased rapidly with the starving time. Reproductive output was higher in the bugs fed on rabbit. R. neivai is among the least resistant triatomine species.
José Alejandro Martínez-Ibarra
Full Text Available Aspects related to hatching, lifetime, number of blood meals for molting, mortality, feeding time, and postfeeding defecation delay were evaluated and compared in each instar of three North American Triatominae: Triatoma gerstaeckeri, Triatoma lecticularia and Triatoma protracta, all of them fed on rabbits. No significant differences (p > 0.05 were found among the three species regarding mean hatching rate, which was close to 20 days. Egg-to-adult development times were significantly shorter (p < 0.05 for T. lecticularia. Number of blood meals for molting to next instar ranged from one to five for T. protracta, and from one to six for T. gerstaeckeri and T. lecticularia. Mortality rates were higher in younger nymphs of T. lecticularia and T. protracta, while rates in T. gerstaeckeri were higher in fifth-instar nymphs. Mean feeding time was longest in T. gerstaeckeri, followed by T. lecticularia. More than twice the number of T. gerstaeckeri nymphs completed the development process, if compared to the nymphs from the other two species. Defecation delay was less than 10 min for T. lecticularia, T. protracta and the youngest nymphs of T. gerstaeckeri. Results point out that these three species may be important potential vectors of Trypanosoma cruzi for human populations, in areas of Mexico where these species are currently present.
Salazar-Schettino Paz Maria
Full Text Available Vectors of Trypanosoma cruzi, parasite responsible for Chagas disease, are divided in intradomestic, peridomestic and sylvatic. The intradomestic are Triatoma barberi and Triatoma dimidiata, two species that represent the highest health risk among the Mexican population. Triatoma dimidiata is a species found mainly inside human habitats, but in Yucatan, it corresponds to the peridomicile vectors. Also in the peridomicile most of Chagas disease vectors are found: Meccus bassolsae, M. longipennis, M. mazzottii, M pallidipennis, M. phyllosomus, M picturata, Triatoma gerstaeckeri, T mexicana, T rubida, Dipetalogaster máxima (the last two are in the process of becoming adapted to the domicile, Panstrongylus rufotuberculatus which occasionally enters the domicile in its adult stage, and Rhodnius prolixus, which is practically controlled in the country. Peridomestic vectors are of lower risk in the transmission dynamics, as compared to the intradomestic ones. For the control of the intradomestic vectors, health education programs, improvements of housing, and the use of pesticides are essential To control the peridomestic vectors, health education programs are required, as well as the use of mosquito nets on doors and windows and around beds, aside from cementing the stone wall fences.
Salazar Schettino, Paz María; Rosales Piña, José Santiago; Rojas Wastavino, Gloria; Cabrera Bravo, Margarita; Vences Blanco, Mauro; López Cárdenas, Jorge
Triatoma mexicana was described by Herrich-Schaeffer in 1848. In 1940, a male specimen was found in Hidalgo. In 1970, this species was recorded in the state of Queretaro. Later, it was registered in Guanajuato and San Luis Potosi. In the present paper we performed an investigation in 545 dwellings from three counties in the state of Guanajuato, Mexico, from March 2003 to May 2004. The search and capture of triatomines were seasonally performed indoors and outdoors. Entomological indexes were calculated. The risk and no risk relations between triatomine presence and housing construction materials were analyzed. Fourteen triatomines were collected indoors and 151 outdoors. The vectors were collected in houses built with either risky and non-risky materials. Adults go indoors but do not settle there, hence, no relationship was found between the building materials and infestation of houses. Conventional interventions like house improvement or insecticide spraying are not efficient for the control of T. mexicana, because its developmental cycle is accomplished outdoors in the area surrounding the houses.
Full Text Available Triatoma brasiliensis is the most important vector of Chagas disease in the semiarid zone of the Northeast of Brazil. Several authors have reported the occurrence of four chromatic patterns with morphological, ecological, and genetic differences. In order to determine the existence of cytogenetic differentiation between these chromatic forms, we analyzed their karyotypes and the chromosome behavior during the male meiotic process. Triatoma brasiliensis shows distinct and specific chromosome characteristics, which differ from those observed in all other triatomine species. However, no cytogenetic differences were observed between the four chromatic forms of T. brasiliensis. The lack of chromosome differentiation among them could indicate that the populations of this species are in a process of differentiation that does not involve their chromosomal organization.
Ceballos, L A; Piccinali, R V; Berkunsky, I; Kitron, U; Gürtler, R E
Triatoma infestans (Klug), the most important vector of Chagas disease in southern South America, is a highly domiciliated species with well-known sylvatic foci only in the Bolivian Andean valleys and in the Bolivian Chaco, where melanic insects designated as "dark morphs" were found. After the tentative identification of two melanic bugs collected from parrot nests in a forest reserve in the Argentine Chaco as T. infestans, we conducted an intensive search there using mouse-baited sticky traps in summer 2006 and 2007. Four live T. infestans bugs were collected in trees without parrot nests in 288 trap-nights, whereas no bug was collected from inside trees with active parrot nests in 51 trap-nights. To increase bug captures, hollow tree trunks that recently had had Amazona aestiva (Berlepsch) and Aratinga acuticaudata (Vieillot) parrot nests were treated with insecticide fumigant canisters exhibiting strong knockdown power. Four (22%) of 18 trees were positive for T. infestans with a dark phenotype. A fragment of the mitochondrial gene COI of 8 of the 14 triatomine bugs collected was successfully sequenced and confirmed as T. infestans. Most of the bugs were captured from Aspidosperma quebracho-blanco (Schlechter) hollow tree trunks harboring parrot nests. All of the T. infestans collected from the nearest house located at 10 km from the sylvatic foci displayed normal chromatic characters. The repeated finding of T. infestans in sylvatic habitats, albeit at very low density, shows that this species is capable of maintaining viable sylvatic foci in the absence of human hosts and immigration from domestic populations. These are the first confirmed findings of sylvatic T. infestans colonies in Argentina and of dark morphs in the Argentine Chaco.
José Alejandro Martínez-Ibarra
Full Text Available Aspects related to hatching, time-lapse between presenting the blood-meal and beginning of feeding, feeding time, postfeed defecation delay, mortality, and fecundity for each stage of Meccus longipennis life-cycle were evaluated. The bugs were maintained in a dark incubator at 27 ± 1ºC and 80 ± 5% rh, were fed weekly and checked daily for ecdysis or death. The hatching rate observed for 300 eggs was 76.7% and the average time of hatching was 19.8 days. Mean time-lapse between presentation of the blood meal and the beginning of feeding was under 5 min in nymphal stages and postfeed defecation delay was under 10 min in most stages, except in fourth and fifth stages. Mean feeding time was longer than 10 min in most stages, except in fourth stage. One hundred thirty-one nymphs (N (65.5% completed the cycle and the average time from NI to adult was 192.6 ± 34.8 days. The average span in days for each stage was 18.1 for NI, 21.4 for NII, 29.5 for NIII, 45.5 for NIV and 55.9 for NV. The number of bloodmeals at each nymphal stage varied from 1 to 5. The mortality rate was 3.29 for NI, 6.8 for NII, 2.92 for NIII 3.76 for NIV, and 10.16 for NV nymphs. The average number of eggs laid per female in a 9-month period was 615.6. Based on our results, we conclude that M. longipennis has some biological and behavioral characteristics which influence its capacity of becoming infected and transmitting Trypanosoma cruzi to human populations in those areas of Mexico where it is currently present.
Cabello Daniel R
Full Text Available A statistical evaluation of the population dynamics of Panstrongylus geniculatus is based on a cohort experiment conducted under controlled laboratory conditions. Animals were fed on hen every 15 days. Egg incubation took 21 days; mean duration of 1st, 2nd, 3rd, 4th, and 5th instar nymphs was 25, 30, 58, 62, and 67 days, respectively; mean nymphal development time was 39 weeks and adult longevity was 72 weeks. Females reproduced during 30 weeks, producing an average of 61.6 eggs for female on its lifetime; the average number of eggs/female/week was 2.1. Total number of eggs produced by the cohort was 1379. Average hatch for the cohort was 88.9%; it was not affected by age of the mother. Age specific survival and reproduction tables were constructed. The following population parameters were evaluated, generation time was 36.1 weeks; net reproduction rate was 89.4; intrinsic rate of natural increase was 0.125; instantaneous birth and death rates were 0.163 and 0.039 respectively; finite rate of increase was 1.13; total reproductive value was 1196 and stable age distribution was 31.2% eggs, 64.7% nymphs and 4.1% adults. Finally the population characteristics of P. geniculatus lead to the conclusion that this species is a K strategist.
Brenière Simone F
Full Text Available In Mexico, Triatoma longipennis (Usinger, Triatoma picturata (Usinger, and Triatoma pallidipennis (Stal, primary Chagas disease vector species of the phyllosoma complex, were analyzed by randomly amplified polymorphic DNA (RAPD. Sixteen decametric primers resolved individual profiles not identical, but partially discriminative between species. Analysis based on pairwise presence/absence comparisons between the three species was performed using three primers and two outgroup species Triatoma infestans (Klug and Triatoma barberi (Usinger. Fifty-three bands in total were scored, although only two bands were constant among the three phyllosoma complex species. Two other bands were constant only for T. longipennis and T. picturata together, and not present in T. pallidipennis. Neighbor Joining tree and the multiple correspondence analysis discriminated T. pallidipennis clearly from the other two species, although there was overlap between T. longipennis and T. picturata. The results indicate a close relationship between the studied species and support the hypothesis of their recent evolution. The suitability of RAPD to discern populations within the species is discussed.
Janine M Ramsey
Full Text Available Chagas disease is one of the most important yet neglected parasitic diseases in Mexico and is transmitted by Triatominae. Nineteen of the 31 Mexican triatomine species have been consistently found to invade human houses and all have been found to be naturally infected with Trypanosoma cruzi. The present paper aims to produce a state-of-knowledge atlas of Mexican triatomines and analyse their geographic associations with T. cruzi, human demographics and landscape modification. Ecological niche models (ENMs were constructed for the 19 species with more than 10 records in North America, as well as for T. cruzi. The 2010 Mexican national census and the 2007 National Forestry Inventory were used to analyse overlap patterns with ENMs. Niche breadth was greatest in species from the semiarid Nearctic Region, whereas species richness was associated with topographic heterogeneity in the Neotropical Region, particularly along the Pacific Coast. Three species, Triatoma longipennis, Triatoma mexicana and Triatoma barberi, overlapped with the greatest numbers of human communities, but these communities had the lowest rural/urban population ratios. Triatomine vectors have urbanised in most regions, demonstrating a high tolerance to human-modified habitats and broadened historical ranges, exposing more than 88% of the Mexican population and leaving few areas in Mexico without the potential for T. cruzi transmission.
Paz María Salazar Schettino
Full Text Available Triatoma mexicana was described by Herrich-Schaeffer in 1848. In 1940, a male specimen was found in Hidalgo. In 1970, this species was recorded in the state of Queretaro. Later, it was registered in Guanajuato and San Luis Potosi. In the present paper we performed an investigation in 545 dwellings from three counties in the state of Guanajuato, Mexico, from March 2003 to May 2004. The search and capture of triatomines were seasonally performed indoors and outdoors. Entomological indexes were calculated. The risk and no risk relations between triatomine presence and housing construction materials were analyzed. Fourteen triatomines were collected indoors and 151 outdoors. The vectors were collected in houses built with either risky and non-risky materials. Adults go indoors but do not settle there, hence, no relationship was found between the building materials and infestation of houses. Conventional interventions like house improvement or insecticide spraying are not efficient for the control of T. mexicana, because its developmental cycle is accomplished outdoors in the area surrounding the houses.
Danila Blanco de Carvalho
Full Text Available Chagas disease is one of the main parasitic diseases found in Latin America and it is estimated that between six and seven million people are infected worldwide. Its etiologic agent, the protozoan Trypanosoma cruzi, is transmitted by triatomines, some of which from the genus Rhodnius. Twenty species are currently recognized in this genus, including some closely related species with low levels of morphological differentiation, such as Rhodnius montenegrensis and Rhodnius robustus. In order to investigate genetic differences between these two species, we generated large-scale RNA-sequencing data (consisting of four RNA-seq libraries from the heads and salivary glands of males of R. montenegrensis and R. robustus. Transcriptome assemblies produced for each species resulted in 64,952 contigs for R. montenegrensis and 70,894 contigs for R. robustus, with N50 of approximately 2,100 for both species. SNP calling based on the more complete R. robustus assembly revealed 3,055 fixed interspecific differences and 216 transcripts with high levels of divergence which contained only fixed differences between the two species. A gene ontology enrichment analysis revealed that these highly differentiated transcripts were enriched for eight GO terms related to AP-2 adaptor complex, as well as other interesting genes that could be involved in their differentiation. The results show that R. montenegrensis and R. robustus have a substantial quantity of fixed interspecific polymorphisms, which suggests a high degree of genetic divergence between the two species and likely corroborates the species status of R. montenegrensis.
Raúl A Alzogaray
Full Text Available Symptoms of poisoning for deltamethrin and cis-permethrin on nymphs III of Triatoma infestans were described. The time required for incoordination and paralysis were determined. Deltamethrin was equal or more rapid in the onset of the first effect (accordingly to dose, and cis-permethrin in the onset of the second one. There were no significant differences between incoordination doses 50% (IncD50s at different times for the two pyrethroids. They showed equivalent incoordination power, but the nymphs treated with deltamethrin recovered slightly more rapid and in greater amount than the nymphs treated with cis-permethrin. The recovery was inhibited by the simultaneus application of piperonyl butoxide. This result suggests that biotransformation by mixed-function microsomal oxidases are involved in the process of recovery
Amelotti, Ivana; Catal?, Silvia S; Gorla, David E
Abstract Background Triatoma infestans is the main vector of Chagas disease in the Gran Chaco region of South America. The traditional spraying technique used for the application of pyrethroid insecticides has shown low efficiency in the elimination of the vector species populations occupying peridomestic structures of rural houses in the endemic area of Argentina. As part of studies looking for better alternatives, we evaluated the residual effect of insecticidal paints on the mortality of f...
Amelotti, Ivana; Catalá, Silvia S; Gorla, David E
Triatoma infestans is the main vector of Chagas disease in the Gran Chaco region of South America. The traditional spraying technique used for the application of pyrethroid insecticides has shown low efficiency in the elimination of the vector species populations occupying peridomestic structures of rural houses in the endemic area of Argentina. As part of studies looking for better alternatives, we evaluated the residual effect of insecticidal paints on the mortality of fourth instar nymphs of T. infestans. The study was based on an experimental design that included two groups treated with an organophosphate (Inesfly 5A IGR) and a pyrethroid (Inesfly 5A IGR NG) formulations of the paint, that were applied on wood, cement blocks and adobe bricks under natural climatic conditions. A third group was an untreated control. Both paint formulations showed very long residual activity, producing mortality of 84% and 98% (pyrethroid and organophosphate formulations, respectively) after 12 months of the paint application. After eight months, nymphs exposed during 6 hours to the painted surfaces with the pyrethroid and organophosphate formulations showed 81.33% and 100% mortality, respectively. The organophosphate- and pyrethroid-based insecticidal paints showed a very long residual activity on the mortality of fourth instar nymphs of T infestans, compared with the traditional spraying technique used for the application of pyrethroid insecticides in peridomestic structures of rural houses in the endemic region for Chagas disease in the Gran Chaco of Argentina. The application of the paints by trained personnel of the vector control programmes could be considered as an alternative control tool in areas where the traditional methods have failed or showed low efficacy.
Gorla David E
Full Text Available Abstract Background Triatoma infestans is the main vector of Chagas disease in the Gran Chaco region of South America. The traditional spraying technique used for the application of pyrethroid insecticides has shown low efficiency in the elimination of the vector species populations occupying peridomestic structures of rural houses in the endemic area of Argentina. As part of studies looking for better alternatives, we evaluated the residual effect of insecticidal paints on the mortality of fourth instar nymphs of T. infestans. Results The study was based on an experimental design that included two groups treated with an organophosphate (Inesfly 5A IGR™ and a pyrethroid (Inesfly 5A IGR NG™ formulations of the paint, that were applied on wood, cement blocks and adobe bricks under natural climatic conditions. A third group was an untreated control. Both paint formulations showed very long residual activity, producing mortality of 84% and 98% (pyrethroid and organophosphate formulations, respectively after 12 months of the paint application. After eight months, nymphs exposed during 6 hours to the painted surfaces with the pyrethroid and organophosphate formulations showed 81.33% and 100% mortality, respectively. Conclusion The organophosphate- and pyrethroid-based insecticidal paints showed a very long residual activity on the mortality of fourth instar nymphs of T infestans, compared with the traditional spraying technique used for the application of pyrethroid insecticides in peridomestic structures of rural houses in the endemic region for Chagas disease in the Gran Chaco of Argentina. The application of the paints by trained personnel of the vector control programmes could be considered as an alternative control tool in areas where the traditional methods have failed or showed low efficacy.
Grasielle Caldas DÁvila Pessoa
Full Text Available Abstract:INTRODUCTION:Despite the recommendations by interpretation of resistance ratios obtained in laboratory bioassays, little is known about the actual impact of these results in the effectiveness of vector control activities in the field. In this context, our objective was to determine the mean value of different resistance ratios obtained by laboratory bioassays performed as part of the chemical control strategies of Triatoma sordida in the field.METHODS:Field bioassays were developed in Monte Azul and Coração de Jesus (Southeast, Brazil. In each location, samples were formed with three domestic units treated with alpha-cypermethrin 20.0% (Alfatek (r 200 SC. One day after spraying, 10 fifth-instar nymphs remained in contact with the surfaces treated (adobe with plaster, adobe without plaster, or wood with insecticide in plastic cones for 72h. Three cones were exposed inside the intradomicile and the peridomicile. The insects in the control group were exposed to an insecticide-free piece of cardboard. Mortality was measured 72h after removal of the insects from the treated surfaces. The tests were realized in triplicate.RESULTS:Mortality was 100.0% in all locations, except for Monte Azul; Landinho (96.6% and Coração de Jesus; Barriguda (96.6%.CONCLUSIONS:Although the resistant populations in laboratory tests proved to be susceptible in the field, this observation is not sufficient to suggest that the cut-off points used to justify the resistance ratio should be changed. In this sense, we recommend that laboratory and field bioassays are carried out with a greater number of Triatominae populations to allow more in-depth consideration of the subject.
Santos, Filipe Martins; Jansen, Ana Maria; Mourão, Guilherme de Miranda; Jurberg, José; Nunes, Alessandro Pacheco; Herrera, Heitor Miraglia
The transmission cycle of Trypanosoma cruzi in the Brazilian Pantanal region has been studied during the last decade. Although considerable knowledge is available regarding the mammalian hosts infected by T. cruzi in this wetland, no studies have investigated its vectors in this region. This study aimed to investigate the presence of sylvatic triatomine species in different habitats of the Brazilian Pantanal region and to correlate their presence with the occurrences of vertebrate hosts and T. cruzi infection. The fieldwork involved passive search by using light traps and Noireau traps and active search by visual inspection. The light traps were placed at five selected points along forested areas for seven nights during each of the nine excursions. At each point where a light trap was set, eight Noireau traps were placed in palm trees and bromeliads. In all, 88 triatomine bugs were collected: two and one individuals from light traps and Noireau traps, respectively; three from peridomestic areas; 23 in coati nests; and 59 in thornbird nests. In this study, active search in microhabitats showed higher efficiency than passive search, since 95% of the triatomine bugs were caught in nests. Further, triatomine bugs were only found to be infected by T. cruzi in coati nests. Coati nests might act as a point of convergence and dispersion for triatomine bugs and mammal hosts infected by T. cruzi, thereby playing an important role in the sylvatic cycle of T. cruziin the Pantanal region.
Calderón-Fernández, Gustavo M; Girotti, Juan R; Juárez, M Patricia
Triatoma dimidiata Latreille is a major vector of Chagas disease with an extensive geographic distribution from Central Mexico, through Central America, to northern South America. As a result of its variability in phenetic and genetic characters, disagreement concerning its taxonomic status has been raised. In this study, the cuticular hydrocarbon pattern of T. dimidiata populations from Mexico, Belize, Guatemala, Honduras, Costa Rica, and Colombia was analyzed by capillary gas chromatography coupled to mass spectrometry; linear discriminant analysis was used to help elucidate population structure. Vector populations segregated into five distinct groups; specimens from Yucatan Peninsula, together with those from Central Mexico, Central America, and Colombia corresponded to different T. dimidiata subspecies, a putative different species comprising insects from Belize, together with an isolated population collected at bat caves in Guatemala. The analysis revalidates the earlier division of T dimidiata into three subspecies, T. d. maculipennis, T. d. dimidiata, and T. d. capitata; and an additional subspecies and a distinct species are proposed.
Parra-Henao, Gabriel; Angulo, Víctor Manuel; Osorio, Lisardo; Jaramillo-O, Nicolás
Triatoma dimidiata Latreille is the second most important vector of Chagas' disease in Colombia and is found in urban and periurban areas. From January 2007 to June 2008, we performed field work in 8 departments, 18 municipalities, and 44 rural villages, covering most of its known distribution and all of its ecological zones in the country. The goal was to determine the geographical distribution, the ecology, and house infestation indices of T. dimidiata over its range and hence the Chagas' disease transmission risk. In Colombia, T. dimidiata occupies a wide variety of ecosystems, from transformed ecosystems in the Andean biome with shrub and xerofitic vegetation to very dense forests in the humid tropical forests in the Sierra Nevada of Santa Marta. According to genetic and ecological criteria, at least two T. dimidiata forms of this species are present: populations from the northwest of the country (Caribbean plains) are restricted to palm tree habitats, and domestic involvement is limited to sporadic visits because of attraction by light; and populations of the east region (Andean mountains) presenting a complex distributional pattern including sylvatic, peridomestic, and domiciliated ecotopes, and occupying a great variety of life zones. The latter population is of epidemiological importance due to the demonstrated migration and genetical flow of individuals among the different habitats. Control, therefore, must take into account its diversity of habitats. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Martínez-Ibarra, J A; Grant-Guillén, Y; Morales-Corona, Z Y; Haro-Rodríguez, S; Ventura-Rodríguez, L V; Nogueda-Torres, B; Bustos-Saldaña, R
The epidemiological risk of infection by Trypanosoma cruzi Chagas in human populations of western Mexico is still under study. Although most vectors in this region and their vector capability are already known, new studies estimating the risk and the importance of individual Triatominae species (Hemiptera: Reduviidae) for T. cruzi transmission are necessary. For 1 yr, every month, > 400 human dwellings and their surroundings in eight communities of two western Mexico states were searched for triatomines. More than 1,000 specimens representing four species were collected and checked for T. cruzi infection. Based on the usual entomological indices, only the inhabitants of Gavilán El Progreso-La Villita are at serious risk of vectorial infection by T. cruzi. A population of Meccus longipennis (Usinger) was found living in peridomestic rock pile boundary walls after an insecticide spraying. It was confirmed the major role of peridomestic habitats as shelter areas for triatomines, particularly in rock pile boundary walls and chicken roosts. Triatominae presence also was verified in certain sylvatic habitats, including primarily heaps of stones. The important role of M. longipennis in the potential transmission of T. cruzi in the region and the secondary role of M. picturatus (Usinger) and Triatoma barberi Usinger also were confirmed. Null colonization of houses by T. barberi, which was collected primarily in peridomestic habitats, differs from its common intradomiciliary collection in other studies. Meccus pallidipennis (Stål) most probably does not exist in Nayarit. Meccus mazzottii (Usinger) and Meccus phyllosomus (Burmeister) are no longer found in Nayarit and Jalisco. Additional studies are necessary to determine the current epidemiological situation in other areas of western Mexico.
Full Text Available Helopeltis spp. (Hemiptera: Miridae are major sucking pests of cashew (Anacardium occidentale L. in India. Cydnocoris gilvus Brum. (Heteroptera: Reduviidae: Harpactorinae is recorded as a potential predator of Helopeltis spp. Biology, mating behaviour and functional response of C. gilvus were studied by rearing in the laboratory (temperature 26-28 0C; relative humidity 89-94 % with wax moth, Galleria mellonella, larvae. Based on laboratory rearing, the fecundity was 56.33 eggs in 8.67 batches per female. The average stadial period was 37.3 days, with a maximum of 11 days for V instar and a minimum of 4.5 days for III instars. C. gilvus took 45.5 days to complete a generation. The innate capacity of natural increase was 0.07 with a gross reproduction of 67.8 females per female. The adult exhibited a pin and jab mode of predation in a sequence of actions. The sequential action of mating comprised arousal (1.32 min, approach (12.30 min, riding over (140.48 min and copulation (85.40 min. The predator responded to increasing prey density by killing more prey than at lower prey densities
Colonização de ecótopos artificiais pelo Panstrongylus megistus na ilha de Santa Catarina, Florianópolis, Santa Catarina, Brasil Colonization of artificial ecotopes by Panstrongylus megistus at Santa Catarina Island, Florianópolis, Santa Catarina, Brazil
Full Text Available Objetivando verificar a colonização de Panstrongylus megistus em ecótopos artificiais em Florianópolis foram examinados, de 1985 a 1992, 779 anexos peridomiciliares (524 galinheiros, 46 currais e 209 ranchos em 9 localidades e 443 domicílios no distrito de Lagoa, todos na Ilha de Santa Catarina. Todo o ecótopo, incluindo forro e porão das casas, era examinado após aplicação de líquido insentífugo (Pirisa a 5%. A pesquisa nos anexos peri-domiciliares revelou 3 galinheiros e um rancho positivo no distrito de Lagoa, onde foram também encontrados 2 domicílios colonizados pelo P. megistus, com a captura de ovos, ninfas e adultos em todos os ecótopos. Pesquisas dirigidas foram realizadas em dois outros domicílios e em uma escola, nos quais os moradores haviam detectado anteriormente exemplares de P. megistus e, em todos os 3, foi confirmada a colonização pelo triatomíneo. Nos 9 ecótopos artificiais foram coletados 559 ovos, 305 ninfas e 24 adultos de P. megistus, com um índice de infecção pelo T. cruzi de 53,3% (182/329. Índice de infecção semelhante, de 56,5% (78/ 138, foi também encontrado nos adultos de P. megistus oriundos dos ecótopos silvestres e capturados nos domicílios pelos moradores, no período de 1983 a 1991. Os testes de precipitina revelaram, em 94,0% dos insetos examinados (170/181, sangue de uma única fonte alimentar e presença de sangue humano em 80,6% (25/31 dos adultos e em 5,8% (1/17 das ninfas capturados nos domicílios. Os resultados encontrados sugerem a necessidade de adoção de medidas de vigilância epidemiológica com a participação da comunidade, face o risco potencial de domiciliação do P. megistus.The aim of this work was to verify the colonization of Panstrongylus megistus on artificial ecotopes in Florianópolis, in the Santa Catarina Island, South Brazil. For this purpose 443 houses of the Lagoa district and 779 house annexes (524 chicken-houses, 46 corrals and 209 storage-houses in
Bérenger, Jean-Michel; Pluot-Sigwalt, Dominique; Pagès, Frédéric; Blanchet, Denis; Aznar, Christine
An annotated list of the triatomine species present in French Guiana is given. It is based on field collections carried out between 1993-2008, museum collections and a literature review. Fourteen species, representing four tribes and six genera, are now known in this country and are illustrated (habitus). Three species are recorded from French Guiana for the first time: Cavernicola pilosa, Microtriatoma trinidadensis and Rhodnius paraensis. The two most common and widely distributed species are Panstrongylus geniculatus and Rhodnius pictipes. The presence of two species (Panstrongylus megistus and Triatoma maculata) could be fortuitous and requires confirmation. Also, the presence of Rhodnius prolixus is doubtful; while it was previously recorded in French Guiana, it was probably mistaken for R. robustus. A key for French Guiana's triatomine species is provided.
Aspectos ecológicos da tripanossomíase americana: X - Dados populacionais das colônias de Panstrongylus megistus e de Triatoma sordida espontaneamente desenvolvidas em ecótopos artificiais Ecological aspects of South American Trypanosomiasis: X - Populational data on colonies of Panstrogylus megistus and Triatoma sordida spontaneously developed in artificial ecotopes
Oswaldo Paulo Forattini
Full Text Available São determinados alguns aspectos da dinâmica populacional de Panstrongylus megistus e Triatoma sordida. Foram utilizados os dados obtidos nas colônias espontaneamente desenvolvidas em ecótopos artificiais representados por galinheiros experimentais. Aplicou-se o método de análise de distribuições de insetos em seus vários estádios. Os resultados permitiram confirmar informações anteriores sobre a mobilidade de adultos, determinando o período anual de sua dispersão. Pelo menos para essa região sudeste do Brasil, no nordeste do Estado de São Paulo, essas épocas correspondem ao período de setembro a novembro para P. megistus e de janeiro a março para T. sordida. Foi possível medir a duração média dos estádios, bem como a sobrevivência dentro de cada um e através a passagem para todos eles. Os dados obtidos permitem sua aplicação no controle e na vigilância de infestações domiciliares por esses triatomíneos.Spontaneous colonizations of Panstrogylus magistus and Triatoma sordida in experimental fowl houses made possible the stage-frequency analysis so as to obtain some populational parameters. So adult mobility, average stage period, daily and stage survival rates were estimated. Annual period of adult dispersal was defined as Steptember-November for P. magistus and January-March for T. sórdita, at least in this region of Southeastern Brazil. It seems that T. sordida presents higher survival rates than P. megistus. Although the nymph stages periods were very variable, the total value was 298 days for P. megistus and 294 days for T. sordida. The authors presume that these data will be useful for control and surveillance of dweling infestations by these bugs.
Full Text Available No combate à doença de Chagas no Brasil, foi utilizado como primeira medida o controle químico, erradicando o Triatoma infestans, o mais importante vetor, tal combate vem favorecendo o aparecimento de vetores secundários, como Triatoma sordida and Panstrongylus megistus, espécies que podem eventualmente ser encontradas no domicílio, como os triatomíneos provenientes de Bernardino de Campos e Sete Barras por nós examinados que foram encontrados no domicílio e positivos para o T. cruzi, sugerindo que, apesar da doença de Chagas estar controlada no Estado de São Paulo, existe a necessidade de aprimorar os conhecimentos sobre o comportamento destes vetores para que mudanças nas medidas de controle sejam introduzidas.
Aspectos ecológicos da Tripanossomíase americana: VIII - Domiciliação de Panstrongylus megistus e sua presença extradomiciliar Ecological aspects of South American Trypanosomiasis: VIII - Local domiciled and wild pattern of Panstrongylus megistus
Oswaldo Paulo Forattini
Full Text Available São apresentados os resultados iniciais de observações destinadas a evidenciar a presença de Panstrongylus megistus domiciliado e silvestre em uma mesma localidade. Os resultados sugerem a domiciliacão desse triatomíneo ao lado de seus hábitos extradomiciliares. Estes estão localmente predominantes como ocos de árvores que servem de abrigos a animais silvestres. A presença desses focos naturais ocorre nas manchas de florestas residuais e a capacidade invasiva em relação aos ecótopos naturais evidenciou-se através da colonização de galinheiros experimentais instalados nesses locais.Local pattern of domiciled and wild distribution of Panstrongylus megistus was observed through artificial and natural ecotopes investigation. The bug was found inhabiting periodomestic dwellings and hollow trees in the sylvatic environment serving as shelters for wild animals. This was mainly represented by spots of remaining forests. Colonization of experimental chicken houses was obtained suggesting that interchange occurs between natural and artificial ecotopes. So it seems suitable to atribute high ecological valence to this bug population.
Cobben, R.H.; Wygodzinsky, P.
A survey is given of the assassin bugs (Reduviidae) collected on the six Netherlands Antilles. All together 22 species were sampled: 6 Emesinae, 1 Saicinae, 8 Harpactorinae, 1 Piratinae, 4 Stenopodinae, 1 Triatominae and 1 Phymatinae. Sixteen species were captured on the three islands of the Leeward
Morrone, J.J.; Coscarón, M. del C.
The assassin bug genus Rasahus Amyot & Serville (Heteroptera: Reduviidae: Peiratinae) comprises 26 Neotropical species. A cladistic analysis of the genus was carried out using 63 characters from external morphology, body vestiture, and male and female genitalia, with the species considered as
Fungal flora of the digestive tract of Rhodnius prolixus, Rhodnius neglectus, Diptelanogaster maximus and Panstrongylus megistus, vectors of Trypanosoma cruzi, Chagas, 1909 Flora fúngica do trato digestivo de Rhodnius prolixus, Rhodnius neglectus, Diptelanogaster maximus e Panstrongylus megistus vetores de Trypanosoma cruzi, Chagas 1909
Aurea Maria Lage de Moraes
Full Text Available This paper reports a study on the mycobiota in the digestive tract of four important species of triatomines: Rhodnius prolixus, R. neglectus, Diptelanogaster maximus and Panstrongylus megistus. The digestive tracts of 90 adults and 425 nymphs of these four triatomine species were studied and 365 fungal strains were isolated. The genera with the greatest number of species were Aspergillus, Penicillium (14 species in each genus, Acremonium and Cladosporium (three species in each genus, and the most frequent species, in decreasing order, were Aspergillus awamori, Penicillium corylophilum, Cladosporium herbarum and Aspergillus niger. It was concluded that, among the isolated fungi, Aspergillus niger and Penicillium corylophilum might be part of the natural flora of the digestive tract of triatomines.Um estudo da micobiota do trato digestivo de quatro importantes espécies de triatomíneos, Rhodnius prolixus, R. neglectus, Diptelanogaster maximus e Panstrongylus megistus, foi realizado. Foram examinados os tratos digestivos de 90 adultos e 425 ninfas destas espécies de triatomíneos e 365 cepas fúngicas foram isoladas. Os gêneros com o maior número de espécies encontradas foram Aspergillus, Penicillium (14 espécies cada, Acremonium e Cladosporium (3 espécies cada e as espécies mais freqüentes, em ordem decrescente, foram Aspergillus awamori, Penicillium corylophilum, Cladosporium herbarum e Aspergillus niger. Dentre os fungos isolados, concluímos que Aspergillus niger e Penicillium corylophilum possam fazer parte da flora natural do trato digestivo destes triatomíneos.
Psyllids (Hemiptera: Pyslloidea) harbor bacterial symbionts in specialized organs called bacteriomes. Bacteriomes may be subject to manipulation to control psyllid pests including Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) and Cacopsylla pyricola (Forster) (Hemiptera: Psyllidae) if the bi...
La aerotermia como alternativa para el control de Triatoma infestans (Hemiptera, Reduviidae resistentes a deltametrina Air temperature elevation as an alternative for the control of deltamethrin-resistant Triatoma infestans (Hemiptera, Reduviidae
Alberto G. Gentile
Full Text Available Se exploraron los efectos de la elevación artificial de la temperatura del aire sobre las formas embrionarias, ninfales y adultas de Triatoma infestansresistentes a Deltametrina. En laboratorio, se expuso a temperaturas crecientes del aire la progenie completa de T. infestans, para determinar viabilidad de huevos y supervivencia en ninfas y adultos; sobre el terreno, la experimentación se llevó a cabo en una vivienda tipo rancho previamente evaluada como colonizada. Durante la fase de laboratorio se comprobó la inviabilidad del 100% de los huevos y la mortalidad del 100% de las ninfas y adultos expuestos a temperaturas del aire estanco de entre 45ºC y 55ºC, mientras que en la fase de terreno se logró reproducir el efecto ovicida del calor, como así también la negativización de las evaluaciones entomológicas de la vivienda de experimentación, llevadas a cabo a las 72 horas, a los 30, 60 y 90 días. La elevación artificial de la temperatura del aire estanco en las habitaciones resultó ser un método de control de eficacia aceptable, inocuo y técnicamente sencillo.This study explores the effects of artificial air temperature elevation on the embryonic, nymphal, and adult forms of deltamethrin-resistant Triatoma infestans. In the laboratory, complete offspring of T. infestanswere exposed to increasing air temperatures to determine the viability of eggs and survival of nymphs and adults; in the field, the experiment was conducted in a poor rural dwelling previously identified as infested with the vector. The laboratory phase showed 100% non-viability of eggs and 100% mortality of nymphs and adults exposed to airtight temperatures from 45ºC to 55ºC, while the field phase succeeded in reproducing the heat's ovicidal effect and negative conversion of entomological assays in the experimental dwelling, as conducted over the course of 72 hours at 30, 60, and 90 days from the baseline evaluation. Artificial elevation of airtight temperature on dwellings proved to be an acceptable, harmless, and technically simple control method.
Avaliação de óleos essenciais de plantas aromáticas com atividade inseticida em Triatoma infestans (Klug, 1834 (Hemiptera: Reduviidae = Evaluation of essential oils with insecticidal activity in Triatoma infestans (Klug, 1834 (Hemiptera: Reduviidae
Suellem Petilim Gomes
Full Text Available A doenca de Chagas e um dos maiores problemas de saude publica na America Latina. Neste trabalho, foi avaliada a acao inseticida de oleos essenciais de Anacardium humile Cymbopogon nardus, Ocimum basilicum e Eucalyptus urograndis em ninfas do 3‹ e 4‹ estadios dedesenvolvimento de Triatoma infestans por acao topica e pressao a vapor (fumigacao. Para o teste topico foram realizadas duas repeticoes cada uma com cinco ninfas de 3‹ e 4‹ estadios de desenvolvimento de T. infestans. Foi aplicado 1ƒÊL de cada concentracao na regiao dorsal de cada individuo. Para o teste de fumigacao foram utilizados potes de 2 L com tampa vedante. Os oleos essenciais de O. gratissimum e E. urograndis apresentaram atividadeinseticida para T. infestans, e A. humile e C. nardus apresentaram em media 5 e 15% de mortalidade, respectivamente. Para fumigacao, somente o oleo de E. urograndis teve efeito, com 100% de mortalidade sobre T. infestans , sendo que para os outros oleos nao foiobservado efeito de fumigacao. Esse trabalho relata pela primeira vez a acao inseticida de E. urograndis em potes fumigenos para o controle de triatomineos. Os resultados sao importantes devido a busca por novos modelos moleculares com acao inseticida em triatomineos resistentes aos inseticidas sinteticos.Chagas disease is a major public health problem in Latin America. This work aimed to evaluate the insecticide action of essential oils of Anacardium humile, Cymbopogon nardus, Ocimum basilicum and Eucalyptus urograndis on Triatoma infestans nymphs of third and fourth stages of development by topic action and steam pressure (fumigation. Two repetitions were performed at the topic test with five nymphs of third and fourth stages of development of T. infestans. It was applied 1ƒÊL of each concentration on the dorsal region of each nymph. Two-liter pots with sealing covers were used at the fumigation test. The essential oils of O. gratissimum and E. urograndis showed insecticidal activity against T. infestans and A. humile and C. nardus showed an average of 5 and 15% mortality, respectively. For the fumigation, only the E. urograndis oil had effect with 100% of mortality on T. infestans and for the other oils it was not observed any effect of the steam pressure. This paper describes for the first time the insecticidal action of E. urograndis in smoke canister to control bugs. The results are important to the search for new molecular models with insecticidal action in bugs which are resistant to synthetic insecticides.
Avaliação de óleos essenciais de plantas aromáticas com atividade inseticida em Triatoma infestans (Klug, 1834 (Hemiptera: Reduviidae Evaluation of essential oils with insecticidal activity in Triatoma infestans (Klug, 1834 (Hemiptera: Reduviidae
Full Text Available A doença de Chagas é um dos maiores problemas de saúde pública na América Latina. Neste trabalho, foi avaliada a ação inseticida de óleos essenciais de Anacardium humile Cymbopogon nardus, Ocimum basilicum e Eucalyptus urograndis em ninfas do 3° e 4° estádios de desenvolvimento de Triatoma infestans por ação tópica e pressão a vapor (fumigação. Para o teste tópico foram realizadas duas repetições cada uma com cinco ninfas de 3° e 4° estádios de desenvolvimento de T. infestans. Foi aplicado 1µL de cada concentração na região dorsal de cada indivíduo. Para o teste de fumigação foram utilizados potes de 2 L com tampa vedante. Os óleos essenciais de O. gratissimum e E. urograndis apresentaram atividade inseticida para T. infestans, e A. humile e C. nardus apresentaram em média 5 e 15% de mortalidade, respectivamente. Para fumigação, somente o óleo de E. urograndis teve efeito, com 100% de mortalidade sobre T. infestans, sendo que para os outros óleos não foi observado efeito de fumigação. Esse trabalho relata pela primeira vez a ação inseticida de E. urograndis em potes fumígenos para o controle de triatomíneos. Os resultados são importantes devido à busca por novos modelos moleculares com ação inseticida em triatomíneos resistentes aos inseticidas sintéticos.Chagas disease is a major public health problem in Latin America. This work aimed to evaluate the insecticide action of essential oils of Anacardium humile, Cymbopogon nardus, Ocimum basilicum and Eucalyptus urograndis on Triatoma infestans nymphs of third and fourth stages of development by topic action and steam pressure (fumigation. Two repetitions were performed at the topic test with five nymphs of third and fourth stages of development of T. infestans. It was applied 1µL of each concentration on the dorsal region of each nymph. Two-liter pots with sealing covers were used at the fumigation test. The essential oils of O. gratissimum and E. urograndis showed insecticidal activity against T. infestans and A. humile and C. nardus showed an average of 5 and 15% mortality, respectively. For the fumigation, only the E. urograndis oil had effect with 100% of mortality on T. infestans and for the other oils it was not observed any effect of the steam pressure. This paper describes for the first time the insecticidal action of E. urograndis in smoke canister to control bugs. The results are important to the search for new molecular models with insecticidal action in bugs which are resistant to synthetic insecticides.
Observações sôbre o ciclo evolutivo do Triatoma arthurneivai, em condições de laboratório (Hemiptera, Reduviidae Studies on the evolution cycle of Triatoma arthurneivai under laboratory conditions (Hemiptera, Reduviidae
Full Text Available A partir de ovos de fêmeas de Triatoma arthurneivai capturadas no ecótopo natural observou-se o tempo de evolução, em condições de laboratório mantidas à temperatura de 25°C e 60-70% de umidade relativa do ar. Foram oferecidos repastos sanguíneos em camundongo albino, semanalmente. A taxa de eclosão de ovos foi de 92,8%. Observaram-se diferenças entre o tempo de evolução desde a eclosão do ôvo até a muda para adulto, quando os triatomíneos foram criados isoladamente ou em grupos de 2-9 espécimes. O tempo médio dêstes foi de 228,3 dias e o daqueles, de 314,4 dias. O mesmo tempo, também apresentou diferenças quando se levou em consideração o sexo; os machos tiveram um tempo médio de 205,4 dias enquanto para as fêmeas o tempo foi de 274,3 dias. Algumas hipóteses são apresentadas, porém nenhuma ofereceu possibilidades de confirmação. Conclue-se pela necessidade de novos trabalhos para elucidar as dúvidas e, sugere-se possibilidade de novos conhecimentos a serem utilizados no estudo da tripanossomose americana em seus focos naturais.Data about Triatoma arthurneivai reared in laboratory from eggs laids by sylvatic females are reported. Laboratory conditions were maintaned at 25°C of temperature and 60-70% of relative humidity. Blood meal were furnished weekly from white mice sources. Eggs ecloded at a proportion of 92.8%. Differences were observed between triatomid reared in a individual or in a jointly manner. They were maintened in groups of 2-9 specimens each. The egg to adult times were 314.4 and 228.3 days for these two groups. Males reared more faster spent 205.4 days from egg to adult; females took 274.3 days. Some hypotesis were presented for explaining these differences, but no conclusions were reached. It was concluded that new investigations to explain the phenomena and help to understand better the dynamics of the South American trypanosomiasis in their natural foci should be performed.
Sobrevivência e ocorrência de muda em Triatoma infestans Klug (Hemiptera, Reduviidae após choque de temperatura Survival and molting occurrence in Triatoma infestans Klug (Hemiptera, Reduviidae after temperature shocks
Vera Lúcia C.C. Rodrigues
Full Text Available A sobrevivência e a ocorrência de mudas em espécimes de Triatoma infestans foram estudados num período de 30 dias após choques de temperatura. Foi demonstrado que choques hipertérmico e hipotérmico interferem nesses processos, na dependência da temperatura do choque, tempo de sua duração, fase de desenvolvimento e sexo dos espécimes. Dentre as situações experimentais utilizadas, o choque a 0°C por 12 h pareceu produzir a ação mais deletéria, porém choques a 40°C e 0°C mesmo por uma hora são admitidos como afetando o desenvolvimento hormonal que controla a muda. Casos de aumento de sobrevivência pós-choque são sugeridos como tendo sido favorecidos por ação de proteínas de choque térmico.Survival and molting occurrence were studied in specimens of Triatoma infestans over 30 days after temperature shocks. Hyperthermal and hypotermal shocks could be found to affect both survival and molting incidence as a function of temperature and period of the developement phase and sex of the specimens. Considering the various test conditions, the shock at 0°C for 12 h was found to elicit the most deleterious effect, whereas shocks at 40°C and 0°C even for 1 h are interpreted as affecting the hormonal balance which controls molting. Cases of a rise in post-shock survival are suggested to have been favored by heat-shock protein action.
Ocorrência de Psammolestes coreodes Bergroth, 1911 (Hemiptera: Reduviidae: Triatominae no Estado de Mato Grosso do Sul Occurrence of Psammolestes coreodes Bergroth, 1911 (Hemiptera: Reduviidae: Triatominae, in the State of Mato Grosso do Sul
Paulo Silva de Almeida
Full Text Available Neste trabalho, relata-se a ocorrência de Psammolestes coreodes Bergroth, 1911 pela primeira vez no Estado de Mato Grosso do Sul. Em 2006, um espécime foi capturado em um ambiente peridomiciliar do município de Miranda, incluindo o Estado de Mato Grosso do Sul, na distribuição geográfica dessa espécie.This paper describes the occurrence of Psammolestes coreodes Bergroth, 1911, for the first time in the State of Mato Grosso do Sul. In 2006, a specimen was caught in a peridomestic environment in the municipality of Miranda, thereby including Mato Grosso do Sul within the geographical distribution of this species.
Estudos sobre a resistência ao jejum e aspectos nutricionais de Cavernicola lenti Barrett & Arias, 1985 (Hemiptera, Reduviidae, Triatominae Studies on the resistance to fasting and nutritional aspects of Cavernicola lenti Barret & Arias, 1985 (Hemiptera, Reduviida, Triatominae
Jane Margaret Costa
Full Text Available In order to widen the present knowledge on the biology of this species, a study on the resistance to starvation was carried out among all nymphal stages and the adult stage (male and female. All evolutive stages were weighed on precision scale in three different nutritional situations: fed, non-fed and death registered after starvation. This procedure has allowed us to calculate the amount of blood taken in each stage and during the whole cycle, the average loss of weight during starvation and its relations with the initial weight. The insects were fed on mice and after eclosion or ecdisis they were isolated for observation of the starving period. Throuhout the whole experiment they were kept in a B. O. D./DOB incubator (28ºC and 90%R.U.. The resistance to starvation of the insects has grown from the first stage on (average of 15.5 days to the fifth stage (average of 75.64 days; on the adult stage, the resistance period was equal to the third stage with an average of 41.76 for the males and 44.82 for the females. The amount of ingested blood was greater at the fifth stage worth 34.14 mg, corresponding to 2,04 times its initial weight. The average weight loss during the starvation was greater at the adult stage (23.95 mg, corresponding to 61.52% of the total weight.
Estudos sobre a resistência ao jejum e aspectos nutricionais de Triatoma lecticularia (Stal, 1859 (Hemiptera, Reduviidae, Triatominae Studies on the resistance to fasting and nutritional aspects of Triatoma lecticularia (Stal, 1859 (Hemiptera, Reduviidae, Triatominae
Full Text Available Foi feito um estudo sobre a resistência ao jejum em todas as fases evolutivas e pesagens em diferentes situações nutricionais de Triatoma lecticularia (alimentado; não alimentado; na morte após o jejum com temperatura e umidade registradas. Observou-se que os períodos de resistência das fases ninfais apresentaram médias (dias crescentes: 1º: 45,84; 2º: 61; 3º: 88,74; 4º: 123,47; 5º 162,30. Na fase adulta as médias foram aproximadas à do 3º estádio (para os machos 88,94 e para as fêmeas 83,66. O procedimento de pesagens permitiu registrar a quantidade de sangue ingerido, a perda de peso durante o jejum e o respectivo percentual em relação ao peso inicial. Esta espécie tem assinalada sua distribuição geográfica na região Neártica, onde tem sido encontrda infectada com Trypanosoma cruzi associada a Neotoma micropus Baird e Spermophilus variagatus (Erxeleben.The resistance to fasting of Triatoma lecticularia was studied in all phases of the life cycle and the insect weighed in different nutritional situations (fed, not fed, death after starvation. The temperature and humidity level were also recorded. The nymphal phases showed increasing resistance to fasting as demonstrated by the following averages (days 1st 45.84; 2nd 61; 3rd 88.74; 4th 123.44; 5th 162.30. Upon the adult phase, the averages were similar to those of the 3rd stage for the male insects 88.94 and for females 83.66. The weighing technique allowed for the measeurement of the quantity of blood ingested, the weight loss during the fast and the percentage weight lost as related to the initial weight. The species is found in the Neartic region where it has been found infected with Trypanosoma cruzi and is associated with the terrestial rodents Neotoma micropus Baird and Spermophilus variagatus (Erxelebem.
Triatoma vandae sp. n. do complexo oliveirai encontrada no estado de Mato Grosso, Brasil (Hemiptera: Reduviidae: Triatominae Triatoma vandae sp.n. of the oliveirai complex from the State of Mato Grosso, Brazil (Hemiptera: Reduviidae: Triatominae
Rodolfo U Carcavallo
Full Text Available There are several specific complexes belonging to the genus Triatoma Laporte, 1832, which are generally associated to specific geographic areas. Recent publications have linked the oliveirai complex to ecosystems of Mato Grosso, which are also present in other Brazilian states and even in other bordering countries as eastern Paraguay. The study of the abundant material collected during the last years allowed the description of several new species of the oliveirai complex: T. jurbergi Carcavallo, Galvão & Lent, 1998; T. baratai Carcavallo & Jurberg, 2000 and T. klugi Carcavallo, Jurberg, Lent & Galvão, 2001. Another new species belonging to the same complex is described here as T. vandae sp.n. It originates from the state of Mato Grosso, and has been reared in the insectary of the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Departamento de Entomologia, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro.
Alberprosenia malheiroi Serra, Atzingen & Serra, 1987 (Hemiptera, Reduviidae: redescrição e bionomia Alberprosenia malheiroi Serra, Atzingen & Serra, 1987 (Hemiptera, Rediviidae: redescription and bionomics
Rodolfo U. Carcavallo
Full Text Available Sobre Alberprosenia malheiroi n. sp. deu-se a conhecer uma diagnose resumida em 1980, porém sem valor bibliográfico. Em 1987 publicou-se a mesma diagnose anexando uma foto e alguns comentários, porém sem realizar uma descrição formal. Descreve-se para esta espécie, os adultos, os estádios imaturos, determina-se a série sintípica e apresenta-se dados bionômicos e de criação em insetário. As diferenças mais evidentes com A. goyovargasi, a única espécie que se conhecia do gênero até então, são a coloração geral negra, o espaço interocular maior que o tamanho de um olho visto dorsalmente, os tubérculos do colar com o ápice agudo e o tamanho maior, na nova espécie, quase o dobro do da primeira espécie. Os ovos são pequenos, fixados ao substrato em grupos de 3 ou 4, elipsóides, não achatados lateralmente, com o opérculo proeminente, convexo, sem estruturas evidentes. As ninfas apresentam em todos os estádios caracteres típicos do gênero e da tribo, com região anteocular menos longa que a post-ocular e característica pilosidade do tegumento que vai se acentuando a cada estádio. A. malheiroi n. sp. foi capturado em ecótopos silvestres em palmeiras em floresta no Estado do Pará, associados com morcegos ou aves. Nenhum dos exemplares estava infectado com Trypanosoma cruzi. Esses triatomíneos foram mantidos em insetários a ± 25°C e ± 60% UR, são insetos ágeis e voam com relativa facilidade. Alimentaram-se bem em pombos e morcegos e não aceitaram alimentação em ratos, camundongos ou hamsters. O período de incubação dos ovos foi em média treze dias e o tempo de evolução do período ninfal foi em média cento e trinta e dois dias.Alberprosenia malheiroi n. sp. first became known through an informal publication of a paper submitted a Congress, in 1980. The same diagnosis with a photograph was published in 1987, but no formal description has yeet been made. The present authors describe adults and immature instars, establish a sintypical series and introduce bionomic data and data on the rearing of this species in insectary.The most evident differences between A. malheiroi n. sp. and A. goyovargasi, the former generic species, are the general colour pattern which is completely black; the interocular area, wider than an eye in dorsal view; the acute apex in collar tubercules and the significantly larger size, almost double that of the latter specie. The eggs are small attach themselves to the substratum in groups of either 3 or 4, are elipsoid with no lateral flattening, having a convex and prominent operculum, without conspicuous structures. Nymphs have the typical tribal and generic characteristics in each stage, the anteocular region being shorter than the postocular one. Pilosity appears in the second instar and becomes more evident with instar development. A. malheiroi n. sp. was captured in a forest, in wild (palm-tree ecotopes associated with bats or birds, in the State of Para, Brazil. Trypanosoma cruzi was not found in any specimens. These triatomines were reared in ± 25°C and ± 60 % RH, the insects are quick and fly without difficulty. They fed well on pigeons and bats but not on rats, mice or hamsters. The eggs incubation period was thirteen days on average, and the evolution time of the nymphal period was a hundred and thirty two days on average.
Full Text Available The aim of the currrent investigation was to evaluate (a the toxicity of three pyrethroids (deltamethrin, lambda-cyhalothrin, and tetramethrin; (b the effect of these insecticides on the locomotor activity; and (c the repellent effect of N,N-diethyl-m-toluamide (DEET on two deltamethrin-resistant strains of Triatoma infestans from Argentina (El Chorro and La Toma, and one susceptible strain. The resistance ratios (RRs obtained for the La Toma strain were: > 10,769, 50.7, and > 5.2 for deltamethrin, lambda-cyhalothrin, and tetramethrin respectively. The RRs for the El Chorro strain were: > 10,769, 85.8, and > 5.2 for deltamethrin, lambda-cyhalothrin, and tetramethrin respectively. The hyperactivity usually caused by the three pyrethroids was in both the deltamethrin-resistant strains compared to the susceptible reference strain. No differences were observed in the repellent effect of DEET between the three groups. These results indicate that the deltamethrin-resistant insects have a cross resistance to lambda-cyhalothrin and tetramethrin, and are also resistant to the first symptom of pyrethroid poisoning (hyperactivity. However, the sensorial process related to DEET repellency does not appear to be altered.
Full Text Available The aim of the work was to investigate the pattern of chemoreceptor sensilla in adults and fifth stage nymphs of Rhodnius prolixus, R. neglectus, Triatoma infestans and T. sordida in order to study differences and similarities between genera and species. Three types of sensilla were analyzed by light microscopy: thin-walled trichoidea, thick-walled trichoidea and basiconica. The number of sensilla of each three types were counted. The length of the antennal segments were also used as a variable for the analysis. The statistical analysis showed that the number of these antennal chemoreceptors had significant differences between species and between adults and nymphs of each species. Discriminant analysis separates incompletely the fifth stage nymphs of the four species and showed similarity between them. Discriminant analysis performed with 12 variables of the antennae, allowed a complete separation of the adults of the four species.
Roca-Acevedo, G; Picollo, M I; Capriotti, N; Sierra, I; Santo-Orihuela, P L
Chagas disease is a zoonosis transmitted to man by blood-sucking triatomine bugs found in the Americas. Triatoma infestans (Klug, 1834) is the main vector of Chagas' disease in Argentina. The control of this illness relies heavily on vector control through the use of insecticide. However, resistance to pyrethroid insecticides associated with ineffective field treatments has been increasingly reported in T. infestans from Argentina and Bolivia. There are few reports on the expression and causes of resistance in eggs of resistant populations, and even fewer studies on insecticide resistance throughout embryonic development. In this study, we explore the biochemical and molecular mechanisms potentially associated with the deltamethrin resistance assessed in the developing eggs of the Argentinean (Campo Largo) and Bolivian (Entre Ríos) T. infestans populations.We found measurable activity of monooxigenases and pyrethroid esterases throughout embryonic development. The pyrethroid esterase activity grew steadily throughout development in all the studied populations and was highest in eggs 12 d old. Mean enzyme activity increased from 13.6 to 16.3 and 22.2 picomol 7-hydroxycoumarin/min (7-OHC) in eggs of 4-, 7-, and 12 d old from the susceptible reference bug colony. Mean activity of resistant populations increased from 16.0 to 25.9 picomol 7-OHC/min in eggs of 4- to 12 d old in Entre Ríos population, and from 15.9 to 28.9 picomol 7-OHC/min in Campo Largo population. Molecular analysis of susceptible and resistant developing eggs detected L1014F mutation in both resistant populations, but no L925I mutation was found in any of the studied populations.Higher esterase activity and L1014F presence justify the resistance to pyrethroid throughout developing eggs of both studied T. infestans populations. The description of resistance profiles including resistance mechanisms involved will allow a rational design of campaigns for the control of Chagas disease transmission. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Carlos Brisola Marcondes
Full Text Available We compared, for Triatoma brasiliensis, the egg-laying process and the mortality of adults under conditions of almost permanent darkness and with normal laboratory luminosity. Mortality did not differ between groups. The egg-laying per vial and per female was significantly greater in the group of normal luminosity. We consider that it is not recommendable to keep the adults of this species under complete darkness. Other biological aspects should be analysed in relation to luminosity.
Juliana Chedid Nogared Rossi
Full Text Available This study estimates the factors of artificial environments (houses and peridomestic areas associated with Triatoma sordida occurrence. Manual searches for triatomines were performed in 136 domiciliary units (DUs in two rural localities of Central-West Brazil. For each DU, 32 structural, 23 biotic and 28 management variables were obtained. Multiple logistic regression analysis was performed in order to identify statistically significant variables associated with occurrence of T. sordida in the study areas. A total of 1,057 specimens (99% in peridomiciles, mainly chicken coops of T. sordida were collected from 63 DUs (infestation: 47%; density: ~8 specimens/DU; crowding: ~17 specimens/infested DU; colonisation: 81%. Only six (0.6% out of 945 specimens examined were infected with Trypanosoma cruzi. The final adjusted logistic regression model indicated that the probability of T. sordida occurrence was higher in DU with wooden chicken coops, presence of > 30 animals in wooden corrals, presence of wood piles and presence of food storeroom. The results show the persistence of T. sordida in peridomestic habitats in rural localities of Central-West Brazil. However, the observed low intradomestic colonisation and minimal triatomine infection rates indicate that T. sordida has low potential to sustain high rates of T. cruzi transmission to residents of these localities.
Rodríguez-Planes, L I; Vazquez-Prokopec, G M; Cecere, M C; Canale, D M; Gürtler, R E
The control of nondomiciliated triatomine species adapted to peridomestic habitats represents a challenge because they are connected to sylvatic colonies, and pyrethroid insecticides have limited effects outdoors. The effects of residual insecticide spraying have rarely been assessed on secondary triatomines. Triatoma garciabesi (Carcavallo, Martinez, Cichero, Prosen & Ronderos, 1967) is a nontarget vector that inhabits the dry western Chaco region, and a member of the Triatoma sordida Stål 1859 complex. Little is known on the capacity of T. garciabesi to invade and establish viable domestic or peridomestic colonies, and on its response to residual insecticide sprays directed against Triatoma infestans Klug 1834. The presence and abundance of triatomines were assessed by timed manual collections annually or biannually (spring and fall) during 10 yr after a community-wide insecticide spraying campaign and selective insecticide sprays directed against T. infestans in a rural village of northwestern Argentina. T. garciabesi mainly occupied peridomestic habitats associated with chickens, and was unable to colonize human sleeping quarters. Trees with chickens occurred in nearly all houses and were infested in >25% of the occasions. The abundance of bugs at house-compound level was best explained by a generalized estimating equation model that included selective insecticide sprays during the previous semester (negative effects), chicken abundance (positive effects), seasonality, and their interactions. Our results suggest that insecticide applications targeting T. infestans affected the abundance of T. garciabesi, and reduced the likelihood of future infestation. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Rossi, Juliana Chedid Nogared; Duarte, Elisabeth C; Gurgel-Gonçalves, Rodrigo
This study estimates the factors of artificial environments (houses and peridomestic areas) associated with Triatoma sordida occurrence. Manual searches for triatomines were performed in 136 domiciliary units (DUs) in two rural localities of Central-West Brazil. For each DU, 32 structural, 23 biotic and 28 management variables were obtained. Multiple logistic regression analysis was performed in order to identify statistically significant variables associated with occurrence of T. sordida in the study areas. A total of 1,057 specimens (99% in peridomiciles, mainly chicken coops) of T. sordida were collected from 63 DUs (infestation: 47%; density: ~8 specimens/DU; crowding: ~17 specimens/infested DU; colonisation: 81%). Only six (0.6%) out of 945 specimens examined were infected with Trypanosoma cruzi. The final adjusted logistic regression model indicated that the probability of T. sordida occurrence was higher in DU with wooden chicken coops, presence of > 30 animals in wooden corrals, presence of wood piles and presence of food storeroom. The results show the persistence of T. sordida in peridomestic habitats in rural localities of Central-West Brazil. However, the observed low intradomestic colonisation and minimal triatomine infection rates indicate that T. sordida has low potential to sustain high rates of T. cruzi transmission to residents of these localities. PMID:25946242
Martínez-Ibarra, José Alejandro; Paredes-González, Edgar; Licón-Trillo, Ángel; Montañez-Valdez, Oziel Dante; Rocha-Chávez, Gonzalo; Nogueda-Torres, Benjamín
The values of biological parameters related to hatching, lifespan, the number of blood meals between moults, mortality, time lapse before the beginning of feeding, feeding time and defecation delay for each instar of three Mexican-American species of Triatominae, Triatoma recurva, Triatoma protracta (former subspecies protracta) and Triatoma rubida (former subspecies uhleri), were evaluated and compared. No significant (p > 0.05) differences were recorded among the three species with respect to the average time required to hatch. This time was approximately 19 days. The average egg-to-adult development time was significantly (p < 0.05) shorter for T. rubida. The number of blood meals at each nymphal instar varied from one-five for each species. The mortality rates were higher for the first-instar nymphs of the three species studied. The mean time lapse before the beginning of feeding was between 0.3-3 min for most nymphs of all instars of each species studied. The mean feeding time was the longest for T. recurva, followed by T. protracta. The defecation delay was less than 10 min for T. recurva and T. rubida. Given these results, only T. rubida should be considered an important potential vector of Trypanosoma cruzi transmission to humans in areas of Mexico where these species exist, whereas T. recurva and T. protracta would be of secondary importance.
Rivas, Nancy; Sánchez-Espíndola, Esther; Camacho, Alejandro D; Alejandre-Aguilar, Ricardo
We investigated the morphology and morphometry of eggs from the colonies of the Entomology Laboratory at ENCB-IPN belonging to six species of the genus Meccus and Triatoma recurva, using both light and scanning electron microscopy. Egg ornamentation is an important parameter to consider in the differentiation of species. Samples were observed under a scanning electron microscope. Measurements of fifty eggs per species included length, width, and opercular diameter, which were used for the morphometric analysis. The results showed that the seven species display a polygonal ornamentation dominated by hexagons; the operculum shows also a polygonal ornamental characteristic in each species. Morphometry provided valuable information for discriminating between closely related species of the genus Meccus and Triatoma recurva, a species akin to this group, thereby facilitating the complete discrimination of these species. © 2016 The Society for Vector Ecology.
Mendonça, Vagner José; Alevi, Kaio Cesar Chaboli; Pinotti, Heloisa; Gurgel-Gonçalves, Rodrigo; Pita, Sebastián; Guerra, Ana Letícia; Panzera, Francisco; De Araújo, Renato Freitas; Azeredo-Oliveir, Maria Tercília Vilela De; Rosa, João Aristeu Da
Triatoma bahiensis Sherlock & Serafim, 1967, T. lenti Sherlock & Serafim, 1967, and T. pessoai Sherlock & Serafim, 1967 were described based on material collected in the Brazilian state of Bahia. These species were later included in the T. brasiliensis complex based on their geographic distribution. Triatoma bahiensis and T. pessoai were subsequently synonymized with T. lenti. However, the phylogenetic position of T. lenti within the T. brasiliensis complex has remained doubtful. This study aims to assess the taxonomic status of T. bahiensis and to infer the phylogenetic relationships between T. lenti, T. bahiensis and the other members of the T. brasiliensis species complex. The identities of the species in concern were confirmed by comparisons with high resolution photos of the respective type materials; lectotypes are designated for T. pessoai and T. bahiensis. Morphological, morphometric, molecular, and cytogenetic approaches as well as experimental crosses were used. The low viability of experimental crosses combined with morphological and morphometric data allow the differentiation of T. bahiensis and T. lenti. Pairwise cyt b sequence divergence between T. lenti and T. bahiensis was 2.5%. Cytogenetic and molecular analyses grouped T. lenti and T. bahiensis as members of the T. brasiliensis complex. These results revalidate the specific status of T. bahiensis.
Zamora, D; Klotz, S A; Meister, E A; Schmidt, J O
The kissing bugs--Triatoma rubida (Uhler), Triatoma protracta (Uhler), and Triatoma recurva (Stal)--are common hematophagous bugs in southeastern Arizona and responsible for severe allergic reactions in some individuals who are bitten. They also possess the potential to transmit the blood parasite, Trypanosoma cruzi. We previously found the essential oil, citronella, to be an excellent deterrent of feeding of T. rubida on a restrained mouse. In this work, we tested major components--alcohols, aldehydes, and monoterpenes--of citronella oil for repellency against the three common triatome species endemic in southern Arizona. The following citronella oil components--geraniol, citronellol, limonene, and citronellal--in different concentrations and combinations were tested. All components of citronella oil demonstrated some inhibition of feeding, ranging from very weak inhibition (limonene) to significant inhibition (geraniol and citronellol). A mixture of geraniol and citronellol was found to be repellant at concentrations of .165 and .165 vol%, respectively, for all three triatome species. Citronellal and limonene had no significant repellent activity. The repellent activity of citronella oil appears to be acting through direct contact with the bugs rather than diffusion of vapors. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Oscherov Elena B.
Full Text Available Se realizó el seguimiento longitudinal de cuatro cohortes de 100 huevos cada una. Los insectos fueron criados a 28°C ± 3°C y 63 % ± 10% de humedad relativa, y alimentados cada siete días sobre gallina (Gallus domesticus, durante 40 min. Las cohortes fueron controladas una vez por semana. Se observó un valor constante de supervivencia en las cuatro cohortes, sin picos importantes. La expectativa de vida de los machos, en promedio, fue de 37,4 semanas y la de las hembras 36,8. El tiempo generacional demandó 61,7 semanas. La tasa reproductiva neta indica que esta población se incrementará 143,3 veces con cada generación. La tasa intrínseca de crecimiento natural fue de 0,082 por semana. El máximo valor reproductivo se verificó, en promedio, a la tercer semana del ingreso al estado adulto. La distribución estable de edades de T. sordida sería de 32% huevos, 26% ninfas de primer estadio, 19% ninfas de segundo estadio, 13% ninfas de tercer estadio, 6% ninfas de cuarto estadio, 3% ninfas de quinto estadio y 1% de adultos. Es la primera cita para Argentina sobre la tabla de vida de T. sordida. El análisis de estos parámetros permite considerar que esta especie se comporta como "K estratega", en condiciones experimentales.
Leysa Jackeline Gómez-Sucerquia
Full Text Available Previous studies have reported genetic differences between wild-caught sylvatic, domestic and laboratory pop-ulations of several Triatominae species. The differences between sylvatic and laboratory colonies parallel are similar to the differences observed between sylvatic and domestic populations. Laboratory colonies are frequently used as references for field populations, but the consequences of founder events on the genetic makeup of laboratory or domestic populations are rarely quantified. Our goal was to quantify the genetic change in Rhodnius pallescens populations artificially submitted to founder effects via laboratory colonization. We compared the genetic makeup of two sylvatic populations and their laboratory descendants using a panel of 10 microsatellite markers. Both sylvatic populations were initially collected from palm trees, but the colonies differed in the number of founder insects and amount of time kept in the laboratory. We evaluated allelic polymorphism, differences between expected and observed heterozygosity, estimates of population differentiation (Fst and inbreeding (Fis, Fit and cluster analyses based on Nei's distances. We found a unique genetic structure for each sample population, with significant differentiation between the field insects and each of the laboratory generations. These analyses showed strong founder effects and showed that genetic drift had led to a genetic equilibrium over several generations of isolation. Our results suggest that laboratory colonies of R. pallescens have a different genetic structure than their wild relatives and similar processes likely affect other Triatominae laboratory stocks.
Carcavallo, Rodolfo U; Jurberg, José; Rocha, Dayse da Silva; Galvao, Cleber; Noireau, François; Lent, Herman
There are several specific complexes belonging to the genus Triatoma Laporte, 1832, which are generally associated to specific geographic areas. Recent publications have linked the oliveirai complex to ecosystems of Mato Grosso, which are also present in other Brazilian states and even in other bordering countries as eastern Paraguay. The study of the abundant material collected during the last years allowed the description of several new species of the oliveirai complex: T. jurbergi Carcavallo, Galvão Lent, 1998; T. baratai Carcavallo Jurberg, 2000 and T. klugi Carcavallo, Jurberg, Lent Galvão, 2001. Another new species belonging to the same complex is described here as T. vandae sp.n. It originates from the state of Mato Grosso, and has been reared in the insectary of the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Departamento de Entomologia, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro.
García, Mauricio; Menes, Marianela; Dorn, Patricia L; Monroy, Carlota; Richards, Bethany; Panzera, Francisco; Bustamante, Dulce María
Triatoma dimidiata, a Chagas disease vector distributed in Mexico, Central America, Colombia, Venezuela, Peru and Ecuador, has been studied using genetic markers and four groups have been defined by ITS-2 sequences: 1A, 1B, 2 and 3. To gather evidence on the divergence and reproductive isolation among T. dimidiata ITS-2 groups, we carried out 15 crossbreeding experiments with field-collected sylvan and domestic T. dimidiata from Guatemala where three groups are found: 1A, 2 and 3. Reciprocal crosses between individuals from groups 1A and 2, and a cross between group 2 individuals from different habitats, produced an average 129.78±42.29 eggs with hatching success ranging from 31.6 to 90.1%. The offspring of these crosses reached the adult stage, and crosses between F1 insects produced eggs. These results suggest that there are no pre- or post-zygotic reproductive barriers between groups 1A and 2, or within group 2. Crosses between group 3 females and males from groups 1A or 2 produced on average 85.67±30.26 eggs and none of them hatched. These results support the existence of pre-zygotic barriers between T. dimidiata group 3 and groups 1A and 2. The group 3 individuals were collected in sylvatic environments in Yaxha, Peten, Guatemala. Previously, distinct chromosomal characteristics (cytotype 3) were described in individuals from this population. Based on this evidence we suggest that this population is divergent at the species level from other T. dimidiata populations. Copyright © 2013 Elsevier B.V. All rights reserved.
García, Mauricio; Menes, Marianela; Dorn, Patricia L.; Monroy, Carlota; Richards, Bethany; Panzera, Francisco; Bustamante, Dulce María
Triatoma dimidiata, a Chagas disease vector distributed in Mexico, Central America, Colombia, Venezuela, Peru and Ecuador, has been studied using genetic markers and four groups have been defined by ITS–2 sequences: 1A, 1B, 2 and 3. To gather evidence on the divergence and reproductive isolation among T. dimidiata ITS–2 groups, we carried out 15 crossbreeding experiments with field–collected sylvan and domestic T. dimidiata from Guatemala where three groups are found: 1A, 2 and 3. Reciprocal crosses between individuals from groups 1A and 2, and a cross between group 2 individuals from different habitats, produced an average 129.78±42.29 eggs with hatching success ranging from 31.6% to 90.1%. The offspring of these crosses reached the adult stage, and crosses between F1 insects produced eggs. These results suggest that there are no pre– or post– zygotic reproductive barriers between groups 1A and 2, or within group 2. Crosses between group 3 females and males from groups 1A or 2 produced on average 85.67±30.26 eggs and none of them hatched. These results support the existence of pre– zygotic barriers between T. dimidiata group 3 and groups 1A and 2. The group 3 individuals were collected in sylvatic environments in Yaxha, Peten, Guatemala. Previously, distinct chromosomal characteristics (cytotype 3) were described in individuals from this population. Based on this evidence we suggest that this population is divergent at the species level from other T. dimidiata populations. PMID:24041592
García, Mauricio; Menes, Marianela; Dorn, Patricia L.; Monroy, Carlota; Richards, Bethany; Panzera, Francisco; Bustamante, Dulce María
Triatoma dimidiata, a Chagas disease vector distributed in Mexico, Central America, Colombia, Venezuela, Peru and Ecuador, has been studied using genetic markers and four groups have been defined by ITS–2 sequences: 1A, 1B, 2 and 3. To gather evidence on the divergence and reproductive isolation among T. dimidiata ITS–2 groups, we carried out 15 crossbreeding experiments with field–collected sylvan and domestic T. dimidiata from Guatemala where three groups are found: 1A, 2 and 3. Reciprocal ...
Gómez-Palacio, Andrés; Triana, Omar
Background Triatoma dimidiata is one of the most significant vectors of Chagas disease in Central America and Colombia, and, as in most species, its pattern of genetic variation within and among populations is strongly affected by its phylogeographic history. A putative origin from Central America has been proposed for Colombian populations, and high genetic differentiation among three biographically different population groups has recently been evidenced. Analyses based on putatively neutral markers provide data from which past events, such as population expansions and colonization, can be inferred. We analyzed the genealogies of the nicotinamide adenine dinucleotide dehydrogenase 4 (ND4) and the cytochrome oxidase subunit 1-mitochondrial genes, as well as partial nuclear ITS-2 DNA sequences obtained across most of the eco-geographical range in Colombia, to assess the population structure and demographic factors that may explain the geographical distribution of T. dimidiata in this country. Results The population structure results support a significant association between genetic divergence and the eco-geographical location of population groups, suggesting that clear signals of demographic expansion can explain the geographical distribution of haplotypes of population groups. Additionally, empirical date estimation of the event suggests that the population's expansion can be placed after the emergence of the Panama Isthmus, and that it was possibly followed by a population fragmentation process, perhaps resulting from local adaptation accomplished by orographic factors such as geographical isolation. Conclusion Inferences about the historical population processes in Colombian T. dimidiata populations are generally in accordance with population expansions that may have been accomplished by two important biotic and orographic events such as the Great American Interchange and the uplift of the eastern range of the Andes mountains in central Colombia. PMID:24625572
José Alejandro Martínez-Ibarra
Full Text Available The values of biological parameters related to hatching, lifespan, the number of blood meals between moults, mortality, time lapse before the beginning of feeding, feeding time and defecation delay for each instar of three Mexican-American species of Triatominae, Triatoma recurva, Triatoma protracta (former subspecies protracta and Triatoma rubida (former subspecies uhleri, were evaluated and compared. No significant (p > 0.05 differences were recorded among the three species with respect to the average time required to hatch. This time was approximately 19 days. The average egg-to-adult development time was significantly (p < 0.05 shorter for T. rubida. The number of blood meals at each nymphal instar varied from one-five for each species. The mortality rates were higher for the first-instar nymphs of the three species studied. The mean time lapse before the beginning of feeding was between 0.3-3 min for most nymphs of all instars of each species studied. The mean feeding time was the longest for T. recurva, followed by T. protracta. The defecation delay was less than 10 min for T. recurva and T. rubida. Given these results, only T. rubida should be considered an important potential vector of Trypanosoma cruzi transmission to humans in areas of Mexico where these species exist, whereas T. recurva and T. protracta would be of secondary importance.
David Eladio Gorla
Full Text Available Goat production is an important economic activity for rural communities in the Gran Chaco of Argentina. Goat corrals are important for the survival of peridomestic populations of Triatoma infestans. This study evaluated the impact of modifying the traditional structure of goat corrals on T. infestans populations and goat productivity in the region of Los Llanos (La Rioja. Thirty-nine experimental corrals were constructed and 57 traditional corrals were used as controls. We evaluated the infestations of the control and experimental corrals for five years following construction of the structures. The results showed that the new structures did not prevent the colonization, although it enhanced the detection of infestation at low densities of T. infestans. No significant difference was found in T. infestans population abundance between control and experimental corrals, probably because of the different detectability in the two types of structures, especially among the small nymphs. Although goat productivity average was higher in experimental than in control corrals, no significant difference was found because of high variability. The new structures can be used as a complement to promote the development of rural communities. Acceptability and adoption of the new corrals by the owners was high, as the enclosures offered better protection for the goats, increased growth of kids and facilitated herd handling.
Grasielle Caldas D'Ávila Pessoa
Full Text Available INTRODUCTION: Triatoma brasiliensis is the species of greatest epidemiological relevance in the semi-arid region of Brazil. This species is predominantly found in domestic environments, and it has the ability to build large colonies with high levels of natural infection via Trypanosoma cruzi. Thus, T. brasiliensis is one of the most efficient transmitters of Chagas disease (CD to humans. Despite household spraying with residual insecticides, many areas report persistent reinfestations for reasons that remain poorly understood. Therefore, this study sought to characterize the toxicological profile of deltamethrin in T. brasiliensis from areas with persistent reinfestation in State of Ceará, Brazil. METHODS: The susceptibility reference lineage (SRL was derived from Umari. Serial dilutions of deltamethrin were prepared and applied to the dorsal abdomen of first instar nymphs. The control group received only pure acetone. Mortality was evaluated after 72h. Qualitative tests assessed mortality in response to a diagnostic dose of 1xLD99 (0.851 nanograms of active ingredient per treated nymph of the SRL. RESULTS: The susceptibility profile characterization of the T. brasiliensis populations revealed 50% resistance ratios (RR50 that ranged from 0.32 to 1.21. The percentage of mortality in response to the diagnostic dose was 100%. CONCLUSIONS: We demonstrated that T. brasiliensis was highly susceptible to deltamethrin. The control difficulties found might be related to the recolonization of the triatomines originating from neighboring environments and the possible operational failures related to the process of spraying that enabled specimens less susceptible to deltamethrin to survive.
Full Text Available Introducción. A pesar del control de los insectos domiciliados, se siguen presentando casos de enfermedad de Chagas con la participación en la transmisión de especies peridomiciliarias y selváticas,una de las cuales es Rhodnius robustus, especie reportada con infecciones naturales de Trypanosoma cruzi y T. rangeli. Objetivo. Describir el comportamiento de R. robustus durante su alimentación en condiciones delaboratorio.Materiales y métodos. En cada estadio de desarrollo de R. robustus se analizó el tiempo promedio para alcanzar la repleción, número promedio de deyecciones, porcentaje de individuos que defecan durante la comida y ganancia de peso después de la alimentación. Resultados. Rhodnius robustus tardó entre 19:26 y 44:55 (minutos:segundos en alimentarse arepleción; los insectos defecaron en todos sus diferentes estadios durante la alimentación. El porcentaje de individuos que defecan durante la alimentación varía de 13,3 % a 93,3 %. Por otro lado, el consumo promedio de sangre en el quinto estadio, 337,19 mg, duplica la cantidad ingerida por los adultos, 161,25 mg. Conclusiones. En todos los estadios de R. robustus hay defecación durante la alimentación, factor que favorece su competencia vectorial. Sin embargo, el tiempo para la primera deyección, el porcentaje dedeyecciones y los individuos que defecan durante la comida, así como la cantidad de sangre ingerida, varían entre los estadios, lo cual indica que el comportamiento alimenticio está mediado por variables dependientes de la edad/estadio. http://dx.doi.org/10.7705/biomedica.v33i2.743
Stevens, Lori; Monroy, M. Carlota; Rodas, Antonieta Guadalupe; Hicks, Robin M.; Lucero, David E.; Lyons, Leslie A.; Dorn, Patricia L.
Triatoma dimidiata (Latreille, 1811) is the most abundant and significant insect vector of the parasite Trypanosoma cruzi in Central America, and particularly in Guatemala. Tr. cruzi is the causative agent of Chagas disease, and successful disease control requires understanding the geographic distribution and degree of migration of vectors such as T. dimidiata that frequently re-infest houses within months following insecticide application. The population genetic structure of T. dimidiata collected from six villages in southern Guatemala was studied to gain insight into the migration patterns of the insects in this region where populations are largely domestic. This study provided insight into the likelihood of eliminating T. dimidiata by pesticide application as has been observed in some areas for other domestic triatomines such as Triatoma infestans. Genotypes of microsatellite loci for 178 insects from six villages were found to represent five genetic clusters using a Bayesian Markov Chain Monte Carlo method. Individual clusters were found in multiple villages, with multiple clusters in the same house. Although migration occurred, there was statistically significant genetic differentiation among villages (FRT = 0.05) and high genetic differentiation among houses within villages (FSR = 0.11). Relatedness of insects within houses varied from 0 to 0.25, i.e., from unrelated to half-sibs. The results suggest that T. dimidiata in southern Guatemala moves between houses and villages often enough that recolonization is likely, implying the use of insecticides alone is not sufficient for effective control of Chagas disease in this region and more sustainable solutions are required. PMID:26334816
Full Text Available The subfamily Triatominae, vectors of Chagas disease, comprises 140 species characterized by a highly homogeneous chromosome number. We analyzed the chromosomal distribution and evolution of repeated sequences in Triatominae genomes by Genomic in situ Hybridization using Triatoma delpontei and Triatoma infestans genomic DNAs as probes. Hybridizations were performed on their own chromosomes and on nine species included in six genera from the two main tribes: Triatomini and Rhodniini. Genomic probes clearly generate two different hybridization patterns, dispersed or accumulated in specific regions or chromosomes. The three used probes generate the same hybridization pattern in each species. However, these patterns are species-specific. In closely related species, the probes strongly hybridized in the autosomal heterochromatic regions, resembling C-banding and DAPI patterns. However, in more distant species these co-localizations are not observed. The heterochromatic Y chromosome is constituted by highly repeated sequences, which is conserved among 10 species of Triatomini tribe suggesting be an ancestral character for this group. However, the Y chromosome in Rhodniini tribe is markedly different, supporting the early evolutionary dichotomy between both tribes. In some species, sex chromosomes and autosomes shared repeated sequences, suggesting meiotic chromatin exchanges among these heterologous chromosomes. Our GISH analyses enabled us to acquire not only reliable information about autosomal repeated sequences distribution but also an insight into sex chromosome evolution in Triatominae. Furthermore, the differentiation obtained by GISH might be a valuable marker to establish phylogenetic relationships and to test the controversial origin of the Triatominae subfamily.
Hypša, Václav; Tietz, D. F.; Zrzavý, Jan; Rego, Ryan O. M.; Galvao, C.; Jurberg, J.
Roč. 23, č. 3 (2002), s. 447-457 ISSN 1055-7903 R&D Projects: GA AV ČR IAA6022801 Institutional research plan: CEZ:AV0Z6022909 Keywords : Triatominae * phylogeny * biogeography Subject RIV: EG - Zoology Impact factor: 2.590, year: 2002
Natália Faria Daflon-Teixeira
Full Text Available The influence of blood meal and mating on Triatoma brasiliensis (Neiva female fecundity, fertility, life-span and the preoviposition period were investigated under laboratory conditions. Nourishment increased fecundity, fertility and adult lifespan, whereas mating increased fecundity, fertility and decreased the preoviposition period. Females also required more than one mating to reach their full reproductive potential. Results indicate that both nourishment and mating are important in T. brasiliensis proliferation. Such information will help towards developing effective control strategies of this vector of Chagas disease.
Fernando Braga Stehling Dias
Full Text Available Introduction For the first time we provide the description of the melanic (dark morphotype of Rhodnius nasutus and determine the pattern of genetic inheritance for this characteristic. Methods Dark morph R. nasutus specimens were crossbred with standard (typically patterned R. nasutus. Results We present the first occurrence of the melanic morphotype in the genus Rhodnius. The crossbreeding results demonstrate that the inheritance pattern of this characteristic follows Mendel's simple laws of segregation and an independent assortment of alleles. Conclusions Phenotypic variation of R. nasutus reinforces the heterogeneity found in the Triatominae. Descriptions of new species in this subfamily require rigorous validation criteria.
Maloney, Kathleen M; Ancca-Juarez, Jenny; Salazar, Renzo; Borrini-Mayori, Katty; Niemierko, Malwina; Yukich, Joshua O; Naquira, Cesar; Keating, Joseph A; Levy, Michael Z
The vector of Chagas disease, Triatoma infestans, is largely controlled by the household application of pyrethroid insecticides. Because effective, large-scale insecticide application is costly and necessitates numerous trained personnel, alternative control techniques are badly needed. We compared the residual effect of organophosphate-based insecticidal paint (Inesfly 5A IGR™ (I5A)) to standard deltamethrin, and a negative control, against T. infestans in a simulated natural environment. We evaluated mortality, knockdown, and ability to take a blood meal among 5(th) instar nymphs. I5A paint caused significantly greater mortality at time points up to nine months compared to deltamethrin (Fisher's Exact Test, p paint (Fisher's Exact Tests, p paint may provide an easily-applied means of protection against vectors of Chagas disease. © 2013 The Society for Vector Ecology.
Martínez-Ibarra, José Alejandro; Nogueda-Torres, Benjamín; Salazar-Montaño, Luis Fernando; García-Lino, Juan Carlos; Arroyo-Reyes, Demver; Hernández-Navarro, Juan Ángel
Understanding the biological parameters of some triatomine subspecies of Meccus phyllosomus (Burmeister) is a crucial first step in estimating the epidemiologic importance of this group. Biological parameters related to hatching, lifetime, number of blood meals to molt, percentage of females at the end of the cycle, number of laid eggs, and mortality for each instar of 3 M. phyllosomus subspecies [M. p. mazzottii (Usinger), M. p. pallidipennis (Stål), and M. p. phyllosomus] and their laboratory hybrids were evaluated and compared. No significant differences (P > 0.05) were found among the experimental hybrids (MaPa, MaPhy, PaPhy) and reciprocal cohorts. In 5 (hatching, number of blood meals to molt, accumulative mortality, percentage of females, and mean number of laid eggs) of the 6 studied parameters (with the exception of development time), the hybrid cohorts had better fitness results than the parental cohorts involved in each set of crosses. The increase in hybrid fitness found in our study could lead to an increase in the epidemiologic risks caused by transmission of Trypanosoma cruzi to humans. © 2015 Institute of Zoology, Chinese Academy of Sciences.
Meneguetti, Dionatas Ulises de Oliveira; Castro, Gabriela Vieira de Souza; Castro, Mariane Albuquerque Lima Ribeiro; Souza, Janis Lunier de; Oliveira, Jader de; Rosa, João Aristeu da; Camargo, Luis Marcelo Aranha
This paper reports, for the first time, the presence of Rhodnius stali in the state of Acre and in the Brazilian Amazon. Specimens of R. stali were collected by the Federal University of Acre in Rio Branco. The number of Triatominae species in the State of Acre increased from five to six. This was also the first report of R. stali in the Brazilian Amazon. The occurrence of R. stali is worrisome, since this species has been found naturally infected by Trypanosoma cruzi and there has been evidence of its domiciliation capabilities.
Pereira-Lourenço, Ariane S; Santos-Mallet, Jacenir R; Freitas, Simone P C
The present study focused on spermatophore structure, transfer, and subsequent destination inside bloodfeeding females of the species Triatoma infestans and Rhodnius neglectus. The morphology of the spermatophore differed between the species studied, such that in T. infestans, the shape was ovaloid, whereas in R. neglectus, the shape resembled a rod. Structures' spine-like cuticulars distributed across the inner surface of the vagina of both species were observed; however, the role of these cuticulars is unknown in Triatominae. In both species, there was an opening in the spermatophore exactly where the common oviduct is connected, thereby making it possible to confirm that the process of spermatozoid migration takes place through this opening. The results obtained show that the spermatophores of T. infestans and R. neglectus differ in size, shape, and structure. Therefore, they can be used as taxonomic markers and may provide information regarding physiology and evolution.
Terassini, Flávio Aparecido; Stefanello, Carlise; Camargo, Luís Marcelo Aranha; Meneguetti, Dionatas Ulises de Oliveira
This study reports, for the first time, the presence of Panstrongylus lignarius in the State of Rondonia, Brazil. Specimen of P. lignarius was collected from a flat in an urban area of the municipality of Porto Velho, Western Amazon. With this finding of P. lignarius, the number of Triatominae species in the State of Rondonia has increased from six to seven. The occurrence of P. lignarius is worrisome, because this species has been found to be naturally infected with Trypanosoma cruzi and there has been evidence of its domiciliation capabilities in other countries of South America.
Pita, Sebastian; Panzera, Francisco; Sánchez, Antonio; Panzera, Yanina; Palomeque, Teresa; Lorite, Pedro
The subfamily Triatominae, vectors of Chagas disease, comprises 140 species characterized by a highly homogeneous chromosome number. We analyzed the chromosomal distribution and evolution of repeated sequences in Triatominae genomes by Genomic in situ Hybridization using Triatoma delpontei and Triatoma infestans genomic DNAs as probes. Hybridizations were performed on their own chromosomes and on nine species included in six genera from the two main tribes: Triatomini and Rhodniini. Genomic probes clearly generate two different hybridization patterns, dispersed or accumulated in specific regions or chromosomes. The three used probes generate the same hybridization pattern in each species. However, these patterns are species-specific. In closely related species, the probes strongly hybridized in the autosomal heterochromatic regions, resembling C-banding and DAPI patterns. However, in more distant species these co-localizations are not observed. The heterochromatic Y chromosome is constituted by highly repeated sequences, which is conserved among 10 species of Triatomini tribe suggesting be an ancestral character for this group. However, the Y chromosome in Rhodniini tribe is markedly different, supporting the early evolutionary dichotomy between both tribes. In some species, sex chromosomes and autosomes shared repeated sequences, suggesting meiotic chromatin exchanges among these heterologous chromosomes. Our GISH analyses enabled us to acquire not only reliable information about autosomal repeated sequences distribution but also an insight into sex chromosome evolution in Triatominae. Furthermore, the differentiation obtained by GISH might be a valuable marker to establish phylogenetic relationships and to test the controversial origin of the Triatominae subfamily.
Obara, Marcos Takashi; Barata, José Maria Soares; da Silva, Nilza Nunes; Ceretti Júnior, Walter; Urbinatti, Paulo Roberto; da Rosa, João Aristeu; Jurberg, José; Galvão, Cleber
The objective of this work was to analyze the morphological, morphometrical, and histological characteristics of eggs of four triatomine bugs species still not studied, in order to understand phylogenetic aspects and to facilitate parameters used in taxonomy, with the purpose of a specific and generic characterization of these vectors in public health. The eggs of each species had come from the collections of the Laboratory of Triatomine bugs and Culicid mosquitoes of the Faculdade de Saúde Pública - USP (Faculty of Public Health/USP). The morphologic studies were carried out through optic microscopy (OM) and scanning electronic microscopy (SEM). The eggs were measured with the help of the digital paquimeter Starrett 727. In relation to histological measures, Microtome Leica RM 2145 was used. Similarities were evidenced in the exocorial architecture of the eggs when they were studied by OM and SEM. This similarity among the eggs suggests a recent speciation, probably derived from common ancestry, representing a monophyletic group. Some structures were also detected by the histological cuts. The study has contributed to the magnification and recognition in generic and specific terms of the Triatominae subfamily. These new data will be able to subsidize a better understanding to determine roles for each vector species and to facilitate parameters to be used in taxonomy.
Almeida, Paulo Silva de; Gonçalves, Guilmara Maria do Amaral; Minzão, Luiz Donizethe; Larson, Ramão Virgilio Genro; Cristaldo, Luis Carlos Medina; Ceretti Júnior, Walter; Obara, Marcos Takashi; Barata, José Maria Soares
This paper describes the occurrence of Psammolestes coreodes Bergroth, 1911, for the first time in the State of Mato Grosso do Sul. In 2006, a specimen was caught in a peridomestic environment in the municipality of Miranda, thereby including Mato Grosso do Sul within the geographical distribution of this species.
Oliveira, J; Alevi, K C C; Fonseca, E O L; Souza, O M F; Santos, C G S; Azeredo-Oliveira, M T V; da Rosa, J A
This paper reports on the first occurrence of Psammolestes tertius in the Chapada Diamantina region, located in the city of Seabra, Bahia State, in northeastern Brazil. Following an active search, 24 P. tertius specimens were collected from Phacellodomus rufifrons (rufous-fronted thornbird) nests. The insects did not present any symptoms of infection by Trypanosoma cruzi. P. tertius males were cytogenetically analyzed, and the results were compared with those of other specimens from the Brazilian State of Ceará. Triatomines from both locations presented the same cytogenetic characteristics: 22 chromosomes, little variation in the size of the autosomes, Y chromosomes that were larger than the X chromosomes, a chromocenter formed only by the sex chromosomes during prophase, and autosomes lacking constitutive heterochromatin. However, it is important to note that this species shows intraspecific chromosomal variation. In light of the results obtained, it is recommended that more studies be performed to characterize P. tertius. These studies will be particularly helpful in understanding this species in ecological, biological, biogeographical, and phylogenetic terms.
Díaz, Sebastián; Triana-Chávez, Omar; Gómez-Palacio, Andrés
Molecular systematics is a remarkable approach for understanding the taxonomic traits and allows the exploration of the inter-population dynamics of several species in the Triatominae subfamily that are involved in Trypanosoma cruzi transmission. Compared to other relevant species that transmit vector-borne diseases, such as some species of the Diptera, there are relatively few nuclear genetic markers available for systematic studies in the Triatominae subfamily. Molecular systematic studies performed on Triatominae are based on mitochondrial gene fragments and, less frequently, on nuclear ribosomal genes or spacers. Due to the fact that these markers can occasionally present problems such as nuclear mitochondrial genes (NUMTs) or intra-genomic variation for high gene copy numbers, it is necessary to use additional nuclear markers to more reliably address the molecular evolution of Triatominae. In this study, we performed phylogenetic analysis using the nuclear elongation factor-1 alpha (EF-1α) gene in individuals from 12 species belonging to the Triatomini and Rhodniini tribes. Genetic diversities and phylogenetic topologies were compared with those obtained for the mitochondrial 16S rRNA and Cytochrome b (cyt b) genes, as well as for the D2 variable region of the ribosomal 28S rRNA gene. These results indicate that the EF-1α marker exhibits an intermediate level of diversity compared to mitochondrial and nuclear ribosomal genes, and that phylogenetic analysis based on EF-1α is highly informative for resolving deep phylogenetic relationships in Triatominae, such as tribe or genera. Copyright © 2016 Elsevier B.V. All rights reserved.
Meneguetti, Dionatas Ulises de Oliveira; Trevisan, Olzeno; Rosa, Renato Moreira; Camargo, Luís Marcelo Aranha
This paper reports, for the first time, the presence of the Eratyrus mucronatus species in the State of Rondonia, Brazil. These specimens were caught by chance in the forest and later they were collected using luminous traps. After finding these specimens, the number of the Triatominae genera in Rondonia rose to four, while its species rose to seven. Complimentary studies will be conducted in order to allow for clearer understanding the ecology of this arthropod, its possible role in transmitting Chagas' disease and its current geographical distribution.
de Oliveira, Jader; Ravazi, Amanda; Souza, Eder Dos Santos; Moreira, Felipe Ferraz Figueiredo; Galvão, Cleber; da Rosa, João Aristeu; Alevi, Kaio Cesar Chaboli
Chagas disease is caused by Trypanosoma cruzi and transmitted by feces of a triatomine that has the habit of defecating during blood feeding. The salivary glands of triatomines are important to hematophagy because their saliva is rich in anticoagulant and hemolytic proteins. The salivary glands of some Rhodnius species analyzed are reddish due to the presence of nitrophorins (antihemostatic activity). The present study aimed to analyze the color pattern of the salivary glands of 67 triatomine species to evaluate whether the presence of nitrophorins is a synapomorphy of Rhodnius or the tribe Rhodniini, or if it is shared with triatomines of the tribes Triatomini and Cavernicolini. Since only the species of the tribe Rhoniini present red glands, it is admitted that the presence of nitrophorin proteins is a synapomorphy of the tribe Rhodniini and that this tribe has derived more recently when compared with Triatomini and Cavernicolini.
Costa, Jane; Almeida, Carlos E.; Esperanca, Gleidson M.; Morales, Ninive [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Dept.de Entomologia. Lab. da Colecao Entomologica; Mallet, Jacenir R. dos S.; Goncalves, Teresa C.M. [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Lab. Transmissores de Leishmanioses. Nucleo de Ultraestrutura; Prado, Angelo P. do [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Inst. de Biologia. Dept. de Parasitologia
Megaselia scalaris (Loew) is a cosmopolitan and synanthropic scuttle fly, eclectic in its feeding habits and acts as detritivore, parasite, facultative parasite, and parasitoid. Here we report for the first time M. scalaris infesting laboratory colonies of Triatoma brasiliensis Neiva, the most important Chagas disease vector in semiarid areas of Brazil. M. scalaris larvae were found feeding inside bugs; pupae were found in the esophagus and intestinal regions of T. brasiliensis through dissection. Other relevant information about this finding is also described in this note, including some preventive measures to avoid laboratory colonies infestations. (author)
Villacís, Anita G; Marcet, Paula L; Yumiseva, César A; Dotson, Ellen M; Tibayrenc, Michel; Brenière, Simone Frédérique; Grijalva, Mario J
Effective control of Chagas disease vector populations requires a good understanding of the epidemiological components, including a reliable analysis of the genetic structure of vector populations. Rhodnius ecuadoriensis is the most widespread vector of Chagas disease in Ecuador, occupying domestic, peridomestic and sylvatic habitats. It is widely distributed in the central coast and southern highlands regions of Ecuador, two very different regions in terms of bio-geographical characteristics. To evaluate the genetic relationship among R. ecuadoriensis populations in these two regions, we analyzed genetic variability at two microsatellite loci for 326 specimens (n=122 in Manabí and n=204 in Loja) and the mitochondrial cytochrome b gene (Cyt b) sequences for 174 individuals collected in the two provinces (n=73 and=101 in Manabí and Loja respectively). The individual samples were grouped in populations according to their community of origin. A few populations presented positive F IS, possible due to Wahlund effect. Significant pairwise differentiation was detected between populations within each province for both genetic markers, and the isolation by distance model was significant for these populations. Microsatellite markers showed significant genetic differentiation between the populations of the two provinces. The partial sequences of the Cyt b gene (578bp) identified a total of 34 haplotypes among 174 specimens sequenced, which translated into high haplotype diversity (Hd=0.929). The haplotype distribution differed among provinces (significant Fisher's exact test). Overall, the genetic differentiation of R. ecuadoriensis between provinces detected in this study is consistent with the biological and phenotypic differences previously observed between Manabí and Loja populations. The current phylogenetic analysis evidenced the monophyly of the populations of R. ecuadoriensis within the R. pallescens species complex; R. pallescens and R. colombiensis were more closely related than they were to R. ecuadoriensis. Copyright © 2017 Elsevier B.V. All rights reserved.
Dionatas Ulises de Oliveira Meneguetti
Full Text Available INTRODUCTION: This paper reports, for the first time, the presence of the Eratyrus mucronatus species in the State of Rondonia, Brazil. METHODS: These specimens were caught by chance in the forest and later they were collected using luminous traps. RESULTS: After finding these specimens, the number of the Triatominae genera in Rondonia rose to four, while its species rose to seven. CONCLUSIONS: Complimentary studies will be conducted in order to allow for clearer understanding the ecology of this arthropod, its possible role in transmitting Chagas' disease and its current geographical distribution.
Full Text Available An ecological control method, using environmental management operations, based on biological and behavioral characteristics of Triatoma dimidiata (Latreille, 1811, was implemented as a pilot project in an area of Costa Rica where the bug is prevalent. The sample was represented by 20 houses with peridomestic colonies (two also had indoor infestation, divided in two equivalent groups of 10 each. In one group we intervened the houses, i.e. all objects or materials that were serving as artificial ecotopes for the bugs were removed, and the second group was used as control houses. After a year of periodic follow up, it became evident that in those houses with a modified environment the number of insects had decreased notoriously even after the first visits and this was more evident after a period of 12.5 to 13.5 months in which no insects were detected in eight of the houses. It also became clear that in this group of houses, recolonization by wild bugs from the surrounding areas, became more difficult, probably due to the absence of protection from bug predators. In the control houses, with the exception of three in which the inhabitants decided to intervene on their own, and another house with a peculiar situation, the insect populations remained the same or even showed a tendency to increase, as confirmed at the end of the experiment. We believe that the method is feasible, low costing and non contaminating. It could be used successfully in other places where T. dimidiata is common and also in countries where other species colonize peridomestic areas of homes. Environmental management of this kind should seek the participation of the members of the communities, in order to make it a more permanent control measure.
Martínez-Ibarra José Alejandro
Full Text Available Aspects related to hatching, time-lapse between presenting the blood meal and beginning of feeding, feeding time, postfeed defecation delay,life time, mortality and fecundity for each stage of Meccus picturatus, life-cycle were evaluated and compared in two cohorts of M. picturatus fed on hens or rabbits. The hatching rate observed for each of the two studied groups of eggs was 78.1% (n = 2298 on the group fed on hens and 82.1% (n = 2704 on that fed on rabbits, and the average time of hatching was 20 days. Mean time-lapse for beginning feeding was under 3 min in nymphal stages and postfeed defecation delay was under 10 min in all stages, in both cohorts. Mean feeding time was significantly (P 0.05 differences were recorded among the average times from NI to adult in the cohort fed on hens (196.8 ± 15.8 days and the average time in the cohort fed on rabbits (189.5 ± 22.9. The average span in days for each stage fed on hens was not significantly different to the average span for each stage fed on rabbits. The number of blood meals at each nymphal stage varied from 1 to 6 in both cohorts. The mortality rates were higher on fifth nymphal stage, in both cohorts. No significant (P > 0.05 differences were recorded on mortality rates on most nymphal stages of both cohorts. The average number of eggs laid per female from the cohort fed on hens in a 9-month period was 791.1, whereas the average number of eggs in the cohort fed on rabbits was 928.3.
José Alejandro Martínez-Ibarra
Full Text Available Aspects related to hatching, life time, number of blood meals to molt, mortality, feeding time and postfeed defecation delay for each instar of Meccus phyllosomus, M. mazzottii, and M. bassolsae, life-cycle were evaluated and compared in two cohorts of each of those three species, fed on hens or rabbits. No significant (p > 0.05 differences were recorded among cohorts fed on hens respect to cohorts fed on rabbits in M. phyllosomus and M. mazzottii and the average time of hatching was 21.5 days for cohorts fed on hens and 22.5 for cohorts fed on rabbits. Average egg-to-adult development times were no significant (p > 0.05 different between both cohorts of M. phyllosomus and M. mazzotti, independent of the blood meal source. The average span in days for each instar fed on hens was not significantly different to the average span for each instar fed on rabbits, when comparisons were made by species. The number of blood meals at each nymphal instar varied from 1 to 6 in both cohorts of each species. The mortality rates were higher on older nymphs, in both cohorts of M. phyllosomus and M. bassolsae, whereas they were higher on first instar nymphs on M. mazzottii. Mean feeding time was no significant (p > 0.05 different in triatomines fed on hens or fed on rabbits, when each species were compared separately. A similar number of nymphs of each cohort, completed the cycle. Defecation delay was no significant (p > 0.05 different when cohorts fed on hens and fed on rabbits were compared by species. Most of the studied parameters showed no significant (p > 0.05 differences among those cohorts fed on hens and for fed on rabbits, which could mean a high degree of association of those species with birds as much as mammals, under wild conditions, increasing their capacity to colonize human dwellings.
Full Text Available A cohort initiated with 121 eggs, yielding 105 first instar nymphs (eclosion rate: 86.78%, allowed us to observe the entire life cycle of Triatoma ryckmani under laboratory conditions (24ºC and 62% relative humidity, by feeding them on anesthetized hamsters. It was possible to obtain 62 adults and the cycle from egg to adult took a mean of 359.69 days with a range of 176-529 days (mortality rate of nymphs: 40.95%. Mean life span of adults was of 81 days for females and 148 days for males. The developmental periods of 4th and 5th nymphs were longer than those of the other instars. This suggests that young siblings have a better chance of taking a hemolymph meal from older ones, in order to survive during fasting periods during prolonged absences of vertebrate hosts from natural ecotopes. The stomach contents of 37 insects showed blood from rodents (15 cases, lizards (7 cases, birds (6 cases and insect hemolymph (7 cases. Out of 10 insects fed by xenodiagnosis on a Trypanosoma cruzi infected mouse, all but one became infected with the parasite.
Pires Herton Helder Rocha
Full Text Available Eye colour of Triatoma infestans is controlled at a single autosomal locus, with black-eye as the dominant gene and red-eye as the recessive. Inheritance of these characters follows a classical Mendelian system, enabling eye colour to be used as a marker for studies of mating frequency. We found no significant differences in oviposition rates and egg hatching rates irrespective of parental phenotypes. Different mating schedules between red-eye and black-eye parents showed that eye colour did not affect mating competence. Females mated with a single male or with different males together or in succession produced similar numbers of fertile eggs, with the eye colour of the offspring reflecting exposure to the different males. We conclude that although a single mating can provide sufficient sperm for the whole reproductive life of the female, multiple matings can result in balanced assortative sperm usage from the spermatheca.
María Guadalupe Vázquez-Martínez
Full Text Available Introduction The use of entomopathogenic fungi to control disease vectors has become relevant because traditional chemical control methods have caused damage to the environment and led to the development of resistance among vectors. Thus, this study assessed the pathogenicity of entomopathogenic fungi in Triatoma dimidiata. Methods Preparations of 108 conidia/ml of Gliocladium virens, Talaromyces flavus, Beauveria bassiana and Metarhizium anisopliae were applied topically on T. dimidiata nymphs and adults. Controls were treated with the 0.0001% Tween-80 vehicle. Mortality was evaluated and recorded daily for 30 days. The concentration required to kill 50% of T. dimidiata (LC50 was then calculated for the most pathogenic isolate. Results Pathogenicity in adults was similar among B. bassiana, G. virens and T. flavus (p>0.05 and differed from that in triatomine nymphs (p=0.009. The most entomopathogenic strains in adult triatomines were B. bassiana and G. virens, which both caused 100% mortality. In nymphs, the most entomopathogenic strain was B. bassiana, followed by G. virens. The native strain with the highest pathogenicity was G. virens, for which the LC50 for T. dimidiata nymphs was 1.98 x108 conidia/ml at 13 days after inoculation. Conclusions Beauveria bassiana and G. virens showed entomopathogenic potential in T. dimidiata nymphs and adults. However, the native G. virens strain presents a higher probability of success in the field, and G. virens should thus be considered a potential candidate for the biological control of triatomine Chagas disease vectors.
Stevens, Lori; Monroy, M Carlota; Rodas, Antonieta Guadalupe; Hicks, Robin M; Lucero, David E; Lyons, Leslie A; Dorn, Patricia L
Triatoma dimidiata (Latreille, 1811) is the most abundant and significant insect vector of the parasite Trypanosoma cruzi in Central America, and particularly in Guatemala. Tr. cruzi is the causative agent of Chagas disease, and successful disease control requires understanding the geographic distribution and degree of migration of vectors such as T. dimidiata that frequently re-infest houses within months following insecticide application. The population genetic structure of T. dimidiata collected from six villages in southern Guatemala was studied to gain insight into the migration patterns of the insects in this region where populations are largely domestic. This study provided insight into the likelihood of eliminating T. dimidiata by pesticide application as has been observed in some areas for other domestic triatomines such as Triatoma infestans. Genotypes of microsatellite loci for 178 insects from six villages were found to represent five genetic clusters using a Bayesian Markov Chain Monte Carlo method. Individual clusters were found in multiple villages, with multiple clusters in the same house. Although migration occurred, there was statistically significant genetic differentiation among villages (FR T = 0.05) and high genetic differentiation among houses within villages (FSR = 0.11). Relatedness of insects within houses varied from 0 to 0.25, i.e., from unrelated to half-sibs. The results suggest that T. dimidiata in southern Guatemala moves between houses and villages often enough that recolonization is likely, implying the use of insecticides alone is not sufficient for effective control of Chagas disease in this region and more sustainable solutions are required. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Full Text Available Triatoma brasiliensis is considered one of the most important Chagas disease vectors being a widespread species in semiarid areas of northeastern Brazil. The species displays distinct chromatic patterns of the cuticle in different localities. Four populations were analyzed in this study: 1-Caicó, Rio Grande do Norte, it will be called the brasiliensis population; 2-Espinosa, Minas Gerais, the melanica population; 3-Petrolina, Pernambuco, the macromelasoma population, and 4-Juazeiro, Bahia, the darker one in overall cuticle coloration, the Juazeiro population. In order to differentiate the four populations of T. brasiliensis, a comparative morphological analysis of external genital structures and of eggs were carried out. The analysis of the male genital structures evidenced minor individual structural variations that did not correlate with chromatic differences or the geographical origins, emphasizing the importance of examining sufficiently large and representative samples before using minor genital variations for taxonomic diagnosis. By scanning electron microscopy of the egg exochorion, each chromatic population presented a distinct ornamentation pattern. The melanica population differed mainly from the other populations studied since it had about 40.6%, 69.6% and 76.6% more perforations, on each cell exochorion, than the brasiliensis, the Juazeiro and the macromelasoma populations respectively. In the melanica population the perforation layout is also peculiar, with densely distributed perforations over all the egg surface. Morphometric measures of the eggs showed statistically significant differences: the macromelasoma population presented the longest length (2.43 mm while the shortest was recorded in the brasiliensis population (2.29 mm.
Vázquez-Martínez, María Guadalupe; Cirerol-Cruz, Blanca Elva; Torres-Estrada, José Luis; López, Mario Henry Rodríguez
The use of entomopathogenic fungi to control disease vectors has become relevant because traditional chemical control methods have caused damage to the environment and led to the development of resistance among vectors. Thus, this study assessed the pathogenicity of entomopathogenic fungi in Triatoma dimidiata. Preparations of 108 conidia/ml of Gliocladium virens, Talaromyces flavus, Beauveria bassiana and Metarhizium anisopliae were applied topically on T. dimidiata nymphs and adults. Controls were treated with the 0.0001% Tween-80 vehicle. Mortality was evaluated and recorded daily for 30 days. The concentration required to kill 50% of T. dimidiata (LC50) was then calculated for the most pathogenic isolate. Pathogenicity in adults was similar among B. bassiana, G. virens and T. flavus (p>0.05) and differed from that in triatomine nymphs (p=0.009). The most entomopathogenic strains in adult triatomines were B. bassiana and G. virens, which both caused 100% mortality. In nymphs, the most entomopathogenic strain was B. bassiana, followed by G. virens. The native strain with the highest pathogenicity was G. virens, for which the LC50 for T. dimidiata nymphs was 1.98 x108 conidia/ml at 13 days after inoculation. Beauveria bassiana and G. virens showed entomopathogenic potential in T. dimidiata nymphs and adults. However, the native G. virens strain presents a higher probability of success in the field, and G. virens should thus be considered a potential candidate for the biological control of triatomine Chagas disease vectors.
Dionatas Ulises de Oliveira Meneguetti
Full Text Available Abstract: INTRODUCTION: This paper reports, for the first time, the presence of Rhodnius stali in the state of Acre and in the Brazilian Amazon. METHODS: Specimens of R. stali were collected by the Federal University of Acre in Rio Branco. RESULTS: The number of Triatominae species in the State of Acre increased from five to six. This was also the first report of R. stali in the Brazilian Amazon. CONCLUSIONS: The occurrence of R. stali is worrisome, since this species has been found naturally infected by Trypanosoma cruzi and there has been evidence of its domiciliation capabilities.
Braga Marina Vianna
Full Text Available Os efeitos da privação alimentar sobre a oogênese de P. megistus foram estudados em laboratório. Imediatamente após a ecdise imaginária, foram formados seis grupos (GI a GVI de 15 casais, que receberam alimentação da seguinte maneira: GI -- no 5º e no 25º dias de jejum; GII -- no 5º e 35º dias; GIII -- no 5º e no 45º dias; GIV -- no 20º dia; GV -- no 30º dia; GVI -- no 40º dia de jejum. Após esses períodos, todos os grupos receberam alimentação a cada 15 dias. O grupo de controle foi formado por 15 casais, alimentados no 5º dia após a ecdise imaginária e, subseqüentemente, a cada 15 dias. GI apresentou o maior número de acasalamentos, produziu mais ovos e maior fertilidade. GII teve maior vida média, maior fecundidade e maior número de eclosões. GIII apresentou o menor período de sobrevivência, baixas fecundidade, fertilidade e eclosões. GVI apresentou os resultados menos favoráveis em todos os parâmetros, exceto em relação ao período de pré-ovipostura. O grupo de controle apresentou os melhores resultados em todos os parâmetros.
Aspectos ecológicos da Tripanossomíase americana: XII - Variação regional da tendência de Panstrongylus megistus à domiciliação Ecological aspects of South American Trypanosomiasis: XII - Regional variation of the Panstrongylus megistus domiciliary tred
Oswaldo Paulo Forattini
Full Text Available Mediante a instalação de galinheiros experimentais em regiões distintas, observou-se variação da capacidade de colonização espontânea de Panstrongylus megistus nesses ecótopos artificiais. Os resultados positivos foram obtidos em áreas de clima com inverno seco ou chuvoso mas onde a destruição da cobertura vegetal primitiva foi mais intensa. Na região de maior persistência florestal e de clima mais úmido, os resultados foram negativos. A existência de populações silvestres em ambas as zonas sugere que a segunda represente o centro de dispersão da espécie, enquanto na primeira o triatomíneo desenvolveu valência ecológica que lhe possibilita a invasão de ecótopos artificiais. Na dependência do grau de alteração e das condições de utilização do ambiente, a vigilância epidemiológica deverá ser mantida para evitar que a domiciliação do triatomíneo se transforme em problema de saúde pública.The development of spontaneous colonies of Panstrongylus megistus in experimental fowlhouses showed regional variation with positive results in regions with an annual dry season, and negative ones in regions without this well-marked period. Beside this, the influence of the forest cover was suggested. Places with forest relics are shelters of the insect populations developing a higher ecological valence with a tendency to artificial ecotope invasion. Populations living in the more primitive and extensive forest environment of the Serra do Mar system seem to preserve mainly their wild behaviour, without a significant development of invasive power of artificial ecotopes. The association of this evidence, with primitive phytogeographic aspects, suggests that the dispersion center is the Serra do Mar system, from which the insect populations spread towards the west across South America. Man-made evironmental changes, mainly with forest destructions will probably enhance secondary adaptation to human dwellings. So, depending on
J. A. ZETTLER
Genetic structure of Pseudococcus microcirculus (Hemiptera: Pseudococcidae) populations on epiphytic orchids in south Florida. J. A. ZETTLER. ∗. , K. ADAMS, B. FREDERICK, A. GUTTING, N. INGEBRETSEN, A. RAGSDALE and A. SCHREY. Department of Biology, Armstrong State University, Savannah, GA 31419, USA.
Song, Nan; Liang, Ai-Ping; Bu, Cui-Ping
Classically, Hemiptera is comprised of two suborders: Homoptera and Heteroptera. Homoptera includes Cicadomorpha, Fulgoromorpha and Sternorrhyncha. However, according to previous molecular phylogenetic studies based on 18S rDNA, Fulgoromorpha has a closer relationship to Heteroptera than to other hemipterans, leaving Homoptera as paraphyletic. Therefore, the position of Fulgoromorpha is important for studying phylogenetic structure of Hemiptera. We inferred the evolutionary affiliations of twenty-five superfamilies of Hemiptera using mitochondrial protein-coding genes and rRNAs. We sequenced three mitogenomes, from Pyrops candelaria, Lycorma delicatula and Ricania marginalis, representing two additional families in Fulgoromorpha. Pyrops and Lycorma are representatives of an additional major family Fulgoridae in Fulgoromorpha, whereas Ricania is a second representative of the highly derived clade Ricaniidae. The organization and size of these mitogenomes are similar to those of the sequenced fulgoroid species. Our consensus phylogeny of Hemiptera largely supported the relationships (((Fulgoromorpha,Sternorrhyncha),Cicadomorpha),Heteroptera), and thus supported the classic phylogeny of Hemiptera. Selection of optimal evolutionary models (exclusion and inclusion of two rRNA genes or of third codon positions of protein-coding genes) demonstrated that rapidly evolving and saturated sites should be removed from the analyses. PMID:23144967
Almeida Carlos Eduardo
Full Text Available Triatoma rubrovaria has become the most frequently captured triatomine species after the control of T. infestans in the State of Rio Grande do Sul (RS, Brazil. Isoenzymatic and chromatic studies indicate the existence of, at least, two distinct phenotypic patterns of T. rubrovaria in RS. The geographic variation noted through molecular tools may also result in distinct profiles of vectorial potentiality. In order to enhance our understanding of the bionomic knowledge of T. rubrovaria separate batches of the species were collected from different municipalities of RS distant from 72 to 332 km: Santana do Livramento (natural ecotope, Santana do Livramento (artificial ecotope, Santiago (natural ecotope, Canguçu (peridomicile and Encruzilhada do Sul (natural ecotope. A total of 285 specimens were collected, 85 specimens kept sufficient fecal material in their guts for the precipitin analysis. The results indicated the food eclecticism for this species and the anti-rodent serum showed the highest positivity in most localities. From the total of analyzed samples, only 1.3% of unique positivity for human blood was registered, all of them for Santiago population. This reactivity to human blood may be associated to pastures activities in the field.
de Arias, Antonieta Rojas; Carbajal de la Fuente, Ana Laura; Gómez, Ana; Cecere, María Carla; Rolón, Miriam; Gómez, María Celeste Vega; Villalba, Cesia
Despite sustained efforts for eliminating Triatoma infestans , reinfestation still persists in large part of the endemic area of Chagas disease from the Gran Chaco region. Sylvatic T. infestans populations seem to threat success of control programs of domestic T. infestans . In this study, we analyze whether T. infestans collected after a community-wide spraying were survivors or were immigrants from elsewhere using geometric morphometric tools. We used 101 right wings of female T. infestans captured before and after intervention program carried out in 12 de Junio and Casuarina, villages from Paraguayan Chaco, and in Puerto Casado during presprayed collection. There were no significant differences in wing size of domestic T. infestans between pre- and postspraying populations, and between domestic and sylvatic ones. When shape variables originating from postintervention individuals from 12 de Junio were introduced one by one into a discriminant analysis, the greatest weight (53%) was allocated to the sylvatic group. Furthermore, from the prespraying population, 25% were reallocated as postintervention individuals. Only 11% of the insects were reassigned to other groups Puerto Casado and Casuarina. These results suggest that postspraying individuals appear to have different origins. Half of the postspraying individuals from 12 de Junio were similar to the sylvatic ones and 25% of these were similar to those captured in the prespraying period. This remarkable morphometric wings similarity between sylvatic and domestic populations is new evidence suggesting that they could be highly related to each other in the Paraguayan Chaco; human-fed bugs from sylvatic area also support this.
Cecere, M C; Leporace, M; Fernández, M P; Zárate, J E; Moreno, C; Gürtler, R E; Cardinal, M V
We assessed the prevalence of infection with Trypanosoma cruzi, parasite genotypes (discrete typing units, DTUs), and the host-feeding sources of domestic and peridomestic Triatoma infestans Klug and Triatoma eratyrusiformis Del Ponte in eight rural communities of the subandean Calchaqui valleys in northwestern Argentina. We sought to analyze their epidemiological role in the context of routine vector surveillance and control actions. Infection with T. cruzi was determined by optic microscopy or polymerase chain reaction (PCR) amplification of the hypervariable region of kinetoplast DNA minicircles. Parasite genotypes were identified through a multi PCR-based strategy. Bloodmeal contents were tested with a direct ELISA assay against nine antisera. Human sleeping quarters (domiciles) and peridomestic dry-shrub fences concentrated most of the T. infestans and T. eratyrusiformis infected with T. cruzi, respectively. The most frequent host-feeding sources of T. infestans were chickens (73.1%) in peridomiciles and humans (73.3%) in domiciles, whereas T. eratyrusiformis fed more often on cavid rodents (92.6%), which thrived in the dry-shrub fences. The main T. cruzi DTU identified in both vectors was T. cruzi I (TcI). Triatoma eratyrusiformis was implicated in the local circulation of TcI among cavies and perhaps mice, but infection with other typically domestic DTUs (TcVI and TcII/TcV/TcVI) indicated overlap between (peri)domestic transmission cycles in both vector species. Because dry-shrub fences were not targeted for routine insecticide spraying, they may act as sources of (peri)domestic reinfestation. Triatoma eratyrusiformis is an emergent secondary vector of T. cruzi and plays a significant role in the local transmission of T. cruzi. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Provecho, Yael M; Gaspe, M Sol; Fernández, M Del Pilar; Gürtler, Ricardo E
We investigated the dynamics and underlying causes of house (re)infestation with Triatoma infestans (Klug 1834) after a community-wide residual spraying with pyrethroids in a well-defined rural section of Pampa del Indio municipality (northeastern Argentina) over a 4-yr period. House infestation was assessed by timed manual searches, during insecticide applications, and by opportunistic householders' bug collections. All reinfested houses were selectively re-sprayed with insecticides. The resident population comprised Qom (66.6%) and Creole (33.4%) households, whose sociodemographic profiles differed substantially. The prevalence of house infestation dropped, less than expected, from 20.5% at baseline to 5.0% at 14 months postspraying (MPS), and then fluctuated between 0.8 and 4.2% over 21-51 MPS. Postspraying house infestation was positively and highly significantly associated with prespraying infestation. Most of the foci detected over 14-21 MPS were considered persistent (residual), some of which were moderately resistant to pyrethroids and were suppressed with malathion. Infestation patterns over 27-51 MPS suggested bug invasion from internal or external foci, but the sources of most findings were unaccounted for. Local spatial analysis identified two hotspots of postspraying house infestation. Using multimodel inference with model averaging, we corroborated that baseline domestic infestation was closely related to refuge availability, housing quality, and occurrence of peridomestic infestation. The diminished effectiveness of single pyrethroid treatments, partly attributable to moderate resistance compounded with rather insensitive vector detection methods and poor housing conditions, contributed to vector persistence. Improved control strategies combined with broad social participation are needed for the sustainable elimination of vector-borne human Chagas disease from the Gran Chaco. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Carvajal, Guillermo; Picollo, María Inés; Toloza, Ariel Ceferino
The prevention of Chagas disease is based primarily on the chemical control of Triatoma infestans (Klug) using pyrethroid insecticides. However, high resistance levels, correlated with control failures, have been detected in Argentina and Bolivia. A previous study at our laboratory found that imidacloprid could serve as an alternative to pyrethroid insecticides. We studied the delayed toxicity of imidacloprid and the influence of the blood feeding condition of the insect on the toxicity of this insecticide; we also studied the effectiveness of various commercial imidacloprid formulations against a pyrethroid-resistant T. infestans population from the Gran Chaco ecoregion. Variations in the toxic effects of imidacloprid were not observed up to 72 h after exposure and were not found to depend on the blood feeding condition of susceptible and resistant individuals. Of the three different studied formulations of imidacloprid on glass and filter paper, only the spot-on formulation was effective. This formulation was applied to pigeons at doses of 1, 5, 20 and 40 mg/bird. The nymphs that fed on pigeons treated with 20 mg or 40 mg of the formulation showed a higher mortality rate than the control group one day and seven days post-treatment (p < 0.01). A spot-on formulation of imidacloprid was effective against pyrethroid-resistant T. infestans populations at the laboratory level.
Costa, J; Araújo, C A C; Freitas, C A V; Borges-Pereira, J
Trypanosoma cruzi is the causative agent of Chagas disease, transmitted to humans and mammals by blood-sucking hemipteran insects belonging to the Triatominae subfamily. The two main genotypes of T. cruzi (TcI and TcII) differ in many characteristics concerning their genetic profile. Despite the extensive literature on vectors and the etiologic agent, several interactive aspects between these two elements of Chagas disease are still waiting to be further clarified. Here, biological and histological features resulting from the interaction between Albino Swiss mice and T. cruzi isolate PB913 after passages through vectors of the Triatoma brasiliensis species complex were evaluated. Comparing the four members of the T. brasiliensis species complex-Triatoma brasiliensis brasiliensis Neiva, Triatoma brasiliensis macromelasoma Galvão, Triatoma melanica Neiva & Lent, and Triatoma juazeirensis Costa & Felix-no significant differences in parasitemia of the infected mice were observed. At 20 days post-infection, the highest number of parasites was observed in the group of mice that were infected with parasites obtained from T. b. macromelasoma. Tropism of the parasites to different organs such as heart, bladder, and skeletal muscles followed by inflammatory cell infiltrates was observed with quantitative and qualitative differences. Even though the four members of the T. brasiliensis species complex differ in their geographical distribution, morphology, biology, ecology, and genetics, no significant influence on the parasitemia of the T. cruzi PB913 isolate was detected. After evaluation of the tissue samples, a higher pathogenicity of parasites obtained from T. b. brasiliensis was noticeable.
Mendonça, Vagner José; Alevi, Kaio Cesar Chaboli; Medeiros, Lívia Maria de Oliveira; Nascimento, Juliana Damieli; de Azeredo-Oliveira, Maria Tercília Vilela; da Rosa, João Aristeu
The reproductive capacity between Triatoma lenti and Triatoma sherlocki was observed in order to verify the fertility and viability of the offspring. Cytogenetic, morphological and morphometric approaches were used to analyze the differences that were inherited. Experimental crosses were performed in both directions. The fertility rate of the eggs in crosses involving T. sherlocki females was 65% and 90% in F1 and F2 offspring, respectively. In reciprocal crosses, it was 7% and 25% in F1 and F2 offspring, respectively. The cytogenetic analyses of the male meiotic process of the hybrids were performed using lacto-acetic orcein, C-banding and Feulgen techniques. The male F1 offspring presented normal chromosome behavior, a finding that was similar to those reported in parental species. However, cytogenetic analysis of F2 offspring showed errors in chromosome pairing. This post-zygotic isolation, which prevents hybrids in nature, may represent the collapse of the hybrid. This phenomenon is due to a genetic dysregulation that occurs in the chromosomes of F1. The results were similar in the hybrids from both crosses. Morphological features, such as color and size of connexive and the presence of red-orange rings on the femora, were similar to T. sherlocki, while wins size was similar to T. lenti in F1 offspring. The eggshells showed characteristics that were similar to species of origin, whereas the median process of the pygophore resulted in intermediate characteristics in the F1 and a segregating pattern in F2 offspring. Geometric morphometric techniques used on the wings showed that both F1 and F2 offspring were similar to T. lenti. These studies on the reproductive capacity between T. lenti and T. sherlocki confirm that both species are evolutionarily closed; hence, they are included in the brasiliensis subcomplex. The extremely reduced fertility observed in the F2 hybrids confirmed the specific status of the species that were analyzed. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.
Dalva A. Mello
Full Text Available In the present paper the life cycle of Triatoma sordida was studied. The mean length from egg to adult was 213 days. The mean length in days from each stage was: 24.3 (± 1.30 for the first. 32.8 (± 1.45 (2nd, 36.1 (± 1.50 (3rd, 44.6 (± 1.85 (4th and 52.0 (± 1.92 (5th. The mean egg incubation períod was 23.2 (± 1.40. Overall mortality was 18.8% and egg viability was 82.5%.Foi estudado no presente trabalho o ciclo biológico do Triatoma sordida A média da duração do ciclo de ovo a adulto foi 213 dias. A média de duração em dias para cada estágio foi 24,3 (± 1,30 para o primeiro, 32,8 (± 1,45 para o segundo, 36,1 (± 1,50 para o terceiro, 44,6 (± 1,85 para o quarto e 52,0 (± 1,92 para o quinto. A média do período de incubação dos ovos foi 23,2 (± 1,40. A mortalidade em todos ps estágios foi 18,8% e a viabilidade dos ovos foi 82,5%.
Pérez de Rosas, Alicia R; Restelli, María F; Fernández, Cintia J; Blariza, María J; García, Beatriz A
AbstractHere we apply inter-simple sequence repeat (ISSR) markers to explore the fine-scale genetic structure and dispersal in populations of Triatoma infestans . Five selected primers from 30 primers were used to amplify ISSRs by polymerase chain reaction. A total of 90 polymorphic bands were detected across 134 individuals captured from 11 peridomestic sites from the locality of San Martín (Capayán Department, Catamarca Province, Argentina). Significant levels of genetic differentiation suggest limited gene flow among sampling sites. Spatial autocorrelation analysis confirms that dispersal occurs on the scale of ∼469 m, suggesting that insecticide spraying should be extended at least within a radius of ∼500 m around the infested area. Moreover, Bayesian clustering algorithms indicated genetic exchange among different sites analyzed, supporting the hypothesis of an important role of peridomestic structures in the process of reinfestation.
Costa, Jane; Correia, Nathália Cordeiro; Neiva, Vanessa Lima; Gonçalves, Teresa Cristina Monte; Felix, Márcio
Triatoma brasiliensis macromelasoma is revalidated based on the results of previous multidisciplinary studies on the Triatoma brasiliensis complex, consisting of crossing experiments and morphological, biological, ecological and molecular analyses. These taxonomic tools showed the closest relationship between T. b. macromelasoma and Triatoma brasiliensis brasiliensis. T. b. macromelasoma is redescribed based on specimens collected in the type locality and specimens from a F1 colony. The complex now comprises T. b. brasiliensis, T. b. macromelasoma, Triatoma melanica, Triatoma juazeirensis and Triatoma sherlocki. An identification key for all members of the complex is presented. This detailed comparative study of the morphological features of T. b. macromelasoma and the remaining members of the complex corroborates results from multidisciplinary analyses, suggesting that the subspecific status is applicable. This subspecies can be distinguished by the following combination of features: a pronotum with 1+1 narrow brownish-yellow stripes on the submedian carinae, not attaining its apex, hemelytra with membrane cells darkened on the central portion and legs with an incomplete brownish-yellow ring on the apical half of the femora. Because the T. brasiliensis complex is of distinct epidemiological importance throughout its geographic distribution, a precise identification of its five members is important for monitoring and controlling actions against Chagas disease transmission.
Morphological, biological and molecular characterization of three strains of Trypanosoma cruzi Chagas, 1909 (Kinetoplastida, Trypanosomatidae) isolated from Triatoma sordida (Stal) 1859 (Hemiptera, Reduviidae) and a domestic cat
RIMOLDI, ALINE; TOMÉ ALVES, RENATA; AMBRÓSIO, DANIELA LUZ; FERNANDES, MARIA ZENAIDE TITA; MARTINEZ, ISABEL; DE ARAÚJO, RENATO FREITAS; CICARELLI, REGINA MARIA BARRETO; DA ROSA, JOÃO ARISTEU
SUMMARY A study was conducted of the biological, morphological and molecular characters of 3 strains of Trypanosoma cruzi (SI5, SI8 and SIGR3) isolated from specimens of Triatoma sordida collected in Santo Inácio and a domestic cat. In order to carry out the study, the following parameters were evaluated: pre-patent period, parasitaemia curves, morphology of the parasites, mortality rates, histopathological lesions and molecular typing. The strains presented variable pre-patent periods, low parasitaemia and no animal mortality. The morphological study of trypomastigotes showed a predominance of intermediate-width and short-length forms, as well as low nuclear index. Epimastigotes presented a low nuclear index, intermediate-width forms in strains SI5 and SI8, and large-width forms in SIGR3. A shorter length could be noted in strains SI8 and SIGR3, whereas SI5 displayed an intermediate length. The histopathological study did not detect amastigote nests in tissues. The amplification of the divergent domain of 24Sα rRNA, HSP60 and GPI genes of strains SI5, SI8 and SIGR3 classified the 3 strains into Group II. Biological parameters made it possible to classify the strains isolated in Santo Inácio (BA) into Biodeme III, Zymodeme 1 and Group II of T. cruzi. PMID:22217619
Carvajal, Guillermo; Picollo, María Inés; Toloza, Ariel Ceferino
The prevention of Chagas disease is based primarily on the chemical control of Triatoma infestans (Klug) using pyrethroid insecticides. However, high resistance levels, correlated with control failures, have been detected in Argentina and Bolivia. A previous study at our laboratory found that imidacloprid could serve as an alternative to pyrethroid insecticides. We studied the delayed toxicity of imidacloprid and the influence of the blood feeding condition of the insect on the toxicity of this insecticide; we also studied the effectiveness of various commercial imidacloprid formulations against a pyrethroid-resistant T. infestans population from the Gran Chaco ecoregion. Variations in the toxic effects of imidacloprid were not observed up to 72 h after exposure and were not found to depend on the blood feeding condition of susceptible and resistant individuals. Of the three different studied formulations of imidacloprid on glass and filter paper, only the spot-on formulation was effective. This formulation was applied to pigeons at doses of 1, 5, 20 and 40 mg/bird. The nymphs that fed on pigeons treated with 20 mg or 40 mg of the formulation showed a higher mortality rate than the control group one day and seven days post-treatment (p < 0.01). A spot-on formulation of imidacloprid was effective against pyrethroid-resistant T. infestans populations at the laboratory level. PMID:25141281
Full Text Available Se estudió el comportamiento alimenticio y de defecación de Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 y R. pictipes Stal, 1872 alimentados artificialmente con sangre humana en condiciones de laboratorio. La ninfa I de todas las especies no defecaron en la primera media hora después de haber iniciado la ingesta. R. pictipes no se acercó a picar en el alimentador artificial aunque si lo hizo cuando el alimento se ofreció directamente sobre el cuerpo humano. Las ninfas y adultos de R. prolixus mostraron índices de defecación (ID superiores a los correspondientes de las otras especies, y la ninfa III presentó el mayor ID=1.62. La mayoría de individuos de todos los estadíos de desarrollo aceptaron el alimento en un tiempo entre 0 y 3 min y se alimentaron en menos de 15 minutos.Feeding and defecaction behavior of Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 and R. pictipes Stal, 1872, artificially fed on human blood, were studied under laboratory conditions. In all species, first instar nymphs did not defecate in the first 30 minutes after feeding. R. pictipes did not accept artificial feeding but fed directly on humans. Nymph and adult R. prolixus had a higher defecation index (DI than other species; third instar nymphs had the highest DI=1.62. In all instars, most individuals accepted the food in £ 3 minutes and finished feeding in less than 15 minutes.
Farfán-García, Ana E.; Angulo-Silva, Víctor M.
Objetivo Determinar la conducta alimentaria de Triatoma dimidiata en hábitats domiciliarios y extradomiciliarios en una zona endémica de Santander, Colombia. Materiales y métodos Mediante la técnica de ELISA, se procesaron 367 contenidos intestinales de insectos capturados en zonas rurales de los municipios de Capitanejo y Macaravita. Estos fueron procesados por medio de la técnica de ELISA, con 12 antisueros policlonales anti-especie animal específicos. Los hospederos de T. dimidiata fueron ...
Fronza, G; Toloza, A C; Picollo, M I; Spillmann, C; Mougabure-Cueto, G A
Chagas disease is one of the most important parasitic infections in Latin America. The main vector of the protozoan Trypanosoma cruzi in America is Triatoma infestans, a blood-sucking triatomine bug who is widely distributed in the Gran Chaco ecoregion. Control programs in endemic countries are focused in the elimination of triatomine vectors with pyrethroid insecticides. However, chemical control has failed in the Gran Chaco over the last two decades because of several factors. Previous studies have reported the evolution of different levels of resistance to deltamethrin in Tri. infestans Recently, very high resistance has been found in the central area of the Argentine Gran Chaco. However, the origin and the extension of this remarkably resistant focus remain unknown. The aim of this study was to evaluate the geographical variation of deltamethrin susceptibility of Tri. infestans in different endemic provinces of Argentina, with emphasis in the center of the Argentine Gran Chaco ecoregion where this main vector has not been reduced. Populations of Mendoza, San Juan, Santiago del Estero, and Tucumán provinces were all susceptible. Resistant populations were only detected in the province of Chaco, where a mosaic resistant focus was described at the Güemes Department. It was characterized into three pyrethroid resistance categories: susceptible, low, and highly resistant populations. We found the populations with the highest resistance levels to deltamethrin, with resistant ratios over 1000. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Corina María Arroyo
Conclusiones. El fenotipo de sensilla antenal fue útil en la diferenciación intraespecífica de Triatoma dimidiata en diferentes hábitats. Las diferencias en hembras ponen de manifiesto nuevos arreglos sensoriales para la explotación del hábitat a diferencia de los machos, que por su mayor capacidad de dispersión, no se diferenciaron entre los ecotopos. La similitud entre hembras de zona urbana, con hembras de peridomicilio rural permite proponer al fenotipo antenal como un sencillo y eficiente indicador para la determinación del origen de triatominos que intentan colonizar nuevos hábitats.
Grasielle Caldas DÁvila Pessoa
Full Text Available Introduction Triatoma sordida is the most captured Triatomine species in the Brazilian artificial environment. In 2008, the discovery of three Triatomine populations with altered susceptibilities to deltamethrin highlighted the importance of investigating the genetic potential for resistance in triatomines. The purpose of this study was to characterize the susceptibility to deltamethrin of peridomestic T. sordida populations in Minas Gerais, Brazil. Methods A susceptibility reference lineage derived from Uberaba, Minas Gerais, Brazil was used. Serial dilutions of deltamethrin were prepared and applied to the dorsal abdomen of first instar nymphs. The control group received only pure acetone. Mortality was evaluated after 72h. Qualitative tests assessed mortality in response to a diagnostic dose of 1xLD99 of the susceptibility reference lineage. Results Susceptibility profile characterization of T. sordida populations revealed resistance ratios (RR50s ranging from 0.42 to 3.94. The percentage mortality in response to the diagnostic dose varied from 70% to 100%. A comparison of the results obtained in the quantitative and qualitative assays demonstrated a lack of correspondence for some populations. Conclusions We demonstrated that only T. sordida populations that present a RR50>1.0 have altered susceptibility, and the execution of simultaneous field and laboratory tests is required to understand the actual effect of vector control. A possible cause of the observed resistance ratios might be the continuous use of pyrethroids in Brazil since the 1980s.
Badel-Mogollón, Jaime; Rodríguez-Figueroa, Laura; Parra-Henao, Gabriel
Due to the lack of information regarding biophysical and spatio-temporal conditions (hydrometheorologic and vegetal coverage density) in areas with Triatoma dimidiata in the Colombian departments of Santander and Boyacá, there is a need to elucidate the association patterns of these variables to determine the distribution and control of this species. To make a spatio-temporal analysis of biophysical variables related to the distribution of T. dimidiate observed in the northeast region of Colombia. We used the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (IPCC SRES) data bases registering vector presence and hydrometheorologic data. We studied the variables of environmental temperature, relative humidity, rainfall and vegetal coverage density at regional and local levels, and we conducted spatial geostatistic, descriptive statistical and Fourier temporal series analyses. Temperatures two meters above the ground and on covered surface ranged from 14,5°C to 18,8°C in the areas with the higher density of T. dimidiata. The environmental temperature fluctuated between 30 and 32°C. Vegetal coverage density and rainfall showed patterns of annual and biannual peaks. Relative humidity values fluctuated from 66,8 to 85,1%. Surface temperature and soil coverage were the variables that better explained the life cycle of T. dimidiata in the area. High relative humidity promoted the seek of shelters and an increase of the geographic distribution in the annual and biannual peaks of regional rainfall. The ecologic and anthropic conditions suggest that T. dimidiata is a highly resilient species.
Conclusions: Surface temperature and soil coverage were the variables that better explained the life cycle of T. dimidiata in the area. High relative humidity promoted the seek of shelters and an increase of the geographic distribution in the annual and biannual peaks of regional rainfall. The ecologic and anthropic conditions suggest that T. dimidiata is a highly resilient species.
Rita de Cássia Moreira de Souza
Full Text Available Introduction Biological collections are depositories of information on different species and contribute to the knowledge, protection, conservation and maintenance of biodiversity. Methods A list of triatomine species currently included in the Collection of Chagas Disease Vectors (FIOCRUZ-COLVEC was prepared from the database made available by the Reference Center on Environmental Information. Results COLVEC curatorship houses 4,778 specimens of triatomines, of which 811 come from other American countries (Argentina, Bolivia, Colombia, Costa Rica, the United States of America, Guatemala, Mexico, Peru, Uruguay and Venezuela and 3,967 are autochthonous from Brazil. Altogether, 56 species of Chagas disease vectors are represented in the COLVEC: two species of the Tribe Cavernicolini Usinger, 1944; fifteen species of the tribe Rhodniini Pinto, 1926, of which 12 are of the genus Rhodnius and 3 are of the genus Psamolestes; and 39 species of the tribe Triatomini Jeannel, 1919, represented by the genus Dipetalogaster, two species of the genus Eratyrus, two of the genus Meccus, seven of the genus Panstrongylus and 27 of the genus Triatoma. Conclusions This list provides important data on the diversity of triatomines currently included in COLVEC, including the expanded area of Panstrongylus lutzi occurrence in the municipalities Pirapora and Januária, State of Minas Gerais. The maintenance and expansion of the collection ensures the preservation of biodiversity and further studies.
Flor A. Torres P
Full Text Available Introducción: Panstrongylus geniculatus es un triatomino silvestre, vector del Trypanosoma cruzi, intruso en domicilios humanos. Determinar la susceptibilidad a insecticidas de uso común en esta especie es indispensable para detectar prematuramente cepas resistentes. Objetivo: Este estudio se propuso analizar la susceptibilidad a lambdacihalotrina y fenitrotión en dos cepas (laboratorio y campo de P. geniculatus. Metodología: se estableció la susceptibilidad a lambdacihalotrina y fenitrotión por aplicación tópica, en la cepa de laboratorio-Molagavita 2003 y en la población de campo-Chorreras 2012 en ninfas del primer estadio de P. geniculatus. Se calcularon valores de dosis letal 50 y dosis letal 99 (DL50 y la DL99 para cada insecticida. También se determinaron valores de grado de resistencia (GR para cada insecticida: DL50 población de campo/DL50 cepa de laboratorio. Resultados: Las DL50 y DL99 en la población de campo y la cepa de laboratorio (en ng/i, fueron: 1,194; 5,764 y 0,024; 0,131 para lambdacihalotrina y 1,476; 7,354 y 0,482; 5,471 para fenitrotión, respectivamente. Los grados de resistencia fueron: GR= 48,9 para lambdacihalotrina y GR= 3,06 para fenitrotión. Conclusiones: La población de campo mostró resistencia a lambdacihalotrina y fenitrotión, probablemente como consecuencia del uso de agroquímicos en la zona. Implementar medidas para la detección temprana de resistencia en triatominos es importante en el diseño de programas de control vectorial.
Conclusión. T. dimidiata presentó un tiempo de desarrollo intermedio entre los triatominos con amplio rango para algunos individuos, posiblemente debido a la irregularidad en su alimentación. La identificación de un rango de peso homogéneo después de 22 días de ayuno con gran producción de ninfas de V estadio, facilita la aplicación de protocolos estandarizados para establecer criterios de selección de compuestos insecticidas utilizables en los programas de control.
Mónica Flórez M
Full Text Available Introducción: Rhodnius pallescens es una especie silvestre que hace intrusión a las viviendas en zonas en las cuales se han presentado brotes de Chagas agudo en Colombia; y para el estudio de sus características biológicas y el monitoreo de la susceptibilidad o resistencia de poblaciones de campo a insecticidas, se requiere del uso de una gran cantidad de insectos mantenidos en el laboratorio. Objetivo: Establecer condiciones de cría de ninfas de R. pallescens que permitan su mejor aprovechamiento en ensayos biológicos. Metodología: Se utilizó una cepa de laboratorio de R. pallescens proveniente de San Martin (Cesar, Colombia y se realizaron bioensayos para: estimar el tiempo de alimentación, establecer condiciones de cría, estimar tiempos de desarrollo ninfal y comparar la fecundidad usando dos fuentes de alimentación y varios tipos de soporte. Resultados: 60 minutos de ofrecimiento de alimento permite la alimentación de 95% de las ninfas. El promedio de oviposición diario/hembra fue de 2,7 huevos y no varío significativamente con el consumo de sangre de gallina o ratón. La duración promedio del ciclo de vida desde huevo hasta el estadio ninfa-V fue de 128,6 días. El uso de cartulina negra y plumas dentro de los frascos de cría mejora la oviposición. Ninfas-V alimentadas desde ninfa-I y pesadas a los 5 o 6 días permite un aprovechamiento del 89% de las ninfas. Conclusiones: Los resultados de este trabajo brindan conocimiento para la cría masiva y el uso de ninfas de Rhodnius pallescens en ensayos biológicos.
Fernando Braga Stehling Dias
Full Text Available The aim of this work is to present aspects related to the ecology of Rhodnius nasutus Stål, 1859 in palms from Chapada do Araripe in Ceará, Brazil. The following five species of palms were investigated: babaçu (Attalea speciosa, buriti (Mauritia flexuosa, carnaúba (Copernicia prunifera, catolé (Syagrus oleracea and macaúba-barriguda (Acrocomia intumescens. Fifth palms were dissected (10 specimens for each species. The overall infestation index was 86%, with a total of 521 triatomines collected. The Trypanosoma cruzi Chagas, 1909 Index was 16.8% and two insects presented mixed infection with Trypanosoma rangeli Tejera, 1920. A precipitin test showed that R. nasutus from palms of Chapada do Araripe are associated with opossum and bird although other possible bloodmeals were observed. Our results showing a high index of infestation of the palms as well as T. cruzi infection, the association of R. nasutus with the most diverse species of palms and proximity of these palms to houses demonstrate the importance of this area for sylvatic T. cruzi transmission and suggest the need for epidemiological surveillance in the region of the Chapada do Araripe.
Dias, Fernando Braga Stehling; Bezerra, Cláudia Mendonça; Machado, Evandro Marques de Menezes; Casanova, Cláudio; Diotaiuti, Liléia
The aim of this work is to present aspects related to the ecology of Rhodnius nasutus Stål, 1859 in palms from Chapada do Araripe in Ceará, Brazil. The following five species of palms were investigated: babaçu (Attalea speciosa), buriti (Mauritia flexuosa), carnaúba (Copernicia prunifera), catolé (Syagrus oleracea) and macaúba-barriguda (Acrocomia intumescens). Fifth palms were dissected (10 specimens for each species). The overall infestation index was 86%, with a total of 521 triatomines collected. The Trypanosoma cruzi Chagas, 1909 Index was 16.8% and two insects presented mixed infection with Trypanosoma rangeli Tejera, 1920. A precipitin test showed that R. nasutus from palms of Chapada do Araripe are associated with opossum and bird although other possible bloodmeals were observed. Our results showing a high index of infestation of the palms as well as T. cruzi infection, the association of R. nasutus with the most diverse species of palms and proximity of these palms to houses demonstrate the importance of this area for sylvatic T. cruzi transmission and suggest the need for epidemiological surveillance in the region of the Chapada do Araripe.
Víctor Manuel Angulo
Full Text Available Introducción. El estudio de los triatominos en sus ecótopos naturales tiene gran significado en la epidemiología de la enfermedad de Chagas. La recolección de insectos vivos y su establecimiento en insectarios permite realizar incontables estudios. Por ello se necesitan métodos efectivos para la captura de triatominos silvestres, especialmente especies intrusas como Rhodnius prolixus. Objetivo. Comparar cuatro métodos para la captura de triatominos en palmas para medir su efectividad. Materiales y métodos. El estudio se llevó a cabo en la localidad de Maní, departamento de Casanare, Colombia, con predominio de Attalea butyracea. Se compararon cuatro metodologías en 67 palmas: trampas con cebo vivo, búsqueda directa en palmas, tala y disección. Resultados. Los métodos fueron efectivos para recolectar ejemplares juveniles y adultos. La tala y la búsqueda manual mostraron los mayores índices de infestación (100 % y 83,33 %. La trampa Angulo mostró mayores índices de hacinamiento (4,93, densidad (3,76, rango de abundancia (1-13 e índice adulto/ninfa (0,22. La tala y la disección fue el método que significativamente recolectó más triatominos en comparación con los otros (p0,05. Conclusiones. Aunque la tala fue el mejor método para la recolección del mayor número de triatominos, los métodos con el cebo vivo con adhesivos o refugios para atrapar los insectos, fueron una buena alternativa. Entre ellos, la trampa Angulo mostró mejores resultados y evitó la exposición del investigador al riesgo y la intervención de ecotopos naturales. doi: http://dx.doi.org/10.7705/biomedica.v33i4.835
Full Text Available Triatoma brasiliensis macromelasoma is revalidated based on the results of previous multidisciplinary studies on the Triatoma brasiliensis complex, consisting of crossing experiments and morphological, biological, ecological and molecular analyses. These taxonomic tools showed the closest relationship between T. b. macromelasoma and Triatoma brasiliensis brasiliensis. T. b. macromelasoma is redescribed based on specimens collected in the type locality and specimens from a F1 colony. The complex now comprises T. b. brasiliensis, T. b. macromelasoma, Triatoma melanica, Triatoma juazeirensis and Triatoma sherlocki. An identification key for all members of the complex is presented. This detailed comparative study of the morphological features of T. b. macromelasoma and the remaining members of the complex corroborates results from multidisciplinary analyses, suggesting that the subspecific status is applicable. This subspecies can be distinguished by the following combination of features: a pronotum with 1+1 narrow brownish-yellow stripes on the submedian carinae, not attaining its apex, hemelytra with membrane cells darkened on the central portion and legs with an incomplete brownish-yellow ring on the apical half of the femora. Because the T. brasiliensis complex is of distinct epidemiological importance throughout its geographic distribution, a precise identification of its five members is important for monitoring and controlling actions against Chagas disease transmission.
Buitrago, Rosio; Bosseno, Marie-France; Depickère, Stéphanie; Waleckx, Etienne; Salas, Renata; Aliaga, Claudia; Barnabé, Christian; Brenière, Simone Frédérique
Chagas disease is a major public health problem in Latin America. Its etiologic agent, Trypanosoma cruzi, is mainly transmitted through the contaminated faeces of blood-sucking insects called triatomines. Triatoma infestans is the main vector in various countries in South America and recently, several foci of wild populations of this species have been described in Bolivia and other countries. These wild populations are suspected of affecting the success of insecticide control campaigns being carried out in South America. To assess the risk that these T. infestans populations pose to human health, it is helpful to determine blood meal sources. In the present work, blood meals were identified in various Bolivian wild T. infestans populations and in three specific areas, in both wild and intra-peridomestic populations to assess the links between wild and domestic cycles of T. cruzi transmission. PCR-HDA and sequencing of Cytb gene were used to identify these blood meal sources. Fourteen vertebrate species were identified as wild blood meal sources. Of those, the most prevalent species were two Andean endemic rodents, Octodontomys gliroides (36%) and Galea musteloides (30%), while humans were the third most prevalent source (18.7%). Of 163 blood meals from peridomestic areas, more than half were chickens, and the others were generally domestic animals or humans. Interestingly, blood from wild animals was identified in triatomines captured in the peridomestic and domestic environment, and blood from domestic animals was found in triatomines captured in the wild, revealing links between wild and domestic cycles of T. cruzi transmission. The current study suggests that wild T. infestans attack humans in the wild, but is also able to bite humans in domestic settings before going back to its natural environment. These results support the risk to human health posed by wild populations of T. infestans.
Meneguetti, Dionatas Ulisses de Oliveira; Trevisan, Olzeno; Camargo, Luís Marcelo Aranha; Rosa, Renato Moreira
This study analyzed the occurrence and the contamination of triatomines by trypanosomatids in Orbignya speciosa (babassu) specimens in the State of Rondônia, Brazil, in two different environments (pasture and woods). Capture of triatomines on babassus and microscopic search for trypanosomatids in their digestive tube were carried out. Four hundred ninety-four (494) specimens were captured (Rhodnius prolixus and R.robustus), of which 35.6% of the triatomines were positive for trypanosomatids. The high index of natural infection along with the abundance of triatomines points out to the necessity to create an epidemiological surveillance system to monitor vector-borne transmission and deepen the studies on the ecology of such vectors in the Amazon.
Claudiney Biral dos Santos
Full Text Available In Brazil, the colonization of human dwellings by triatomines occurs in areas with native vegetation of the caatinga or cerrado types. In areas of Atlantic forest such as in the Brazilian state of Espírito Santo, there are no species adapted to live in human habitations. The few autochthonous cases of Chagas disease encountered in Espírito Santo have been attributed to adult specimens of Triatoma vitticeps that invade houses from forest remnants. In recent years, the entomology unit of the Espírito Santo State Health Secretariat has recorded nymphs infected with flagellates similar to Trypanosoma cruzi in rural localities. Entomological surveys were carried out in the residences and outbuildings in which the insects were found, and serological examinations for Chagas disease performed on the inhabitants. Four colonies were found, all associated with nests of opossums (Didelphis aurita, 111 specimens of T. vitticeps, and 159 eggs being collected. All the triatomines presented flagellates in their frass. Mice inoculated with the faeces presented trypomastigotes in the circulating blood and groups of amastigotes in the cardiac muscle fibres. Serological tests performed on the inhabitants were negative for T. cruzi. Even with the intense devastation of the forest in Espírito Santo, there are no indications of change in the sylvatic habits of T. vitticeps. Colonies of this insect associated with opossum nests would indicate an expansion of the sylvatic environment into the peridomicile.
Conclusión. Estos resultados demuestran la utilidad de la técnica para la diferenciación entre R. prolixus y R. colombiensis en adición a métodos morfométricos y moleculares previamente utilizados para diferenciar estas dos especies.
Andrea Arévalo; Julio César Carranza; Felipe Guhl; Gustavo Adolfo Vallejo
Introducción. La electroforesis de hemeproteínas salivares en geles de almidón es una técnica de reciente aplicación para diferenciar especies del género Rhodnius que poseen gran similaridad fenotípica o para diferenciar subpoblaciones de la misma especie, separadas geográficamente. De las 15 especies de Rhodnius descritas en latinoamérica, por lo menos ocho han sido reportadas en el territorio colombiano. Objetivo. Utilizar la electroforesis de hemeproteínas salivares para diferenciar R. ...
Materiales y métodos. Se seleccionaron treinta ninfas de cada especie después de xenodiagnóstico artificial en sangre infectada con T. rangeli. Se examinaron periódicamente muestras de heces y hemolinfa. Los insectos con hemolinfas infectadas fueron alimentados en ratones a fin de comprobar la transmisión por picadura y posteriormente disecados para confirmar la infección de las glándulas salivales. Resultados. En Rhodnius pictipes se encontró un mayor porcentaje de infección intestinal que en las otras especies. Se detectaron epimastigotes y tripomastigotes en la hemolinfa de las cuatro especies, y se encontró que el parasitismo fue menor en las especies del linaje R. robustus. Rhodnius robustus y R. neglectus no transmitían T. rangeli a ratones por picadura: después de la disección, sus glándulas no estaban infectadas. Solo un espécimen de R. nasutus y dos de R. pictipes transmitieron el parásito por la picadura. La tasa de infección glandular fue de 16 % para R. pictipes y de 4 % para R. nasutus. Conclusiones. La capacidad infecciosa (hemolinfática, intestinal y glandular y la transmisión de T. rangeli (SC-58/KP1- fueron mayores y más eficientes en R. pictipes. Estos resultados refuerzan la hipótesis de que estos triatominos actúan como filtros biológicos en la transmisión de T. rangeli.
Gersonval Leandro Silva Monte
Full Text Available Introduction Eratyrus mucronatus Stål, 1859 is a wild triatomine vector of Trypanosoma cruzi Chagas, 1909. However, little is known regarding the biology and ecoepidemiology of this triatomine in the Brazilian Amazon. The present study describes the biology of E. mucronatus grown under laboratory conditions and the epidemiological aspects of its natural breeding sites. Methods Five colonies were monitored in the field for 3 years. Temperature and humidity measurements were taken in the mornings and afternoons at the natural breeding sites, and the behavior and distribution of the nymphs and adults were observed in the wild colony. We also monitored the life cycle under controlled laboratory conditions. Results Some factors that were considered decisive for the establishment of these colonies were present at all of the colonies studied in the field. These factors included an active termite nest, a vertebrate for repast, and dry and shaded substrates with temperatures of 24-28°C and with humidity of 80-90%. A generation was developed in 274 days under these microclimatic conditions in the laboratory. Conclusions The climatic variables described in the field indicate that these environmental parameters have a limiting effect on the dispersal and colonization of E. mucronatus to new environments. In addition, the long period of development to adulthood demonstrates that only one generation can develop per year even under the more favorable laboratory conditions.
Silva, Maria Beatriz Araújo; Menezes, Kelly Reis de; Farias, Maria Clara Guerra de; Andrade, Maria Sandra; Victor, Caio Cesar Alves; Lorosa, Elias Seixas; Jurberg, José
Studying the feeding preferences of triatomines is an important entomological surveillance tool, since continuous surveillance of the disease is necessary. The precipitin reaction was used to describe the feeding preferences of triatomines along with their natural infection by flagellates similar to Tyrpanosoma cruzi. Six hundred eighty-seven insects were examined, including Triatoma brasiliensis, Triatoma pseudomaculata, and Panstrongylus lutzi. Sixty-nine (10%) of 687 triatomines examined tested positive for flagellates similar to T. cruzi, and 8 (1.2%) of these fed on human blood. This study found potential transmitters of Chagas disease both inside and outside the domiciliar environment.
Monte, Gersonval Leandro Silva; Tadei, Wanderli Pedro; Farias, Thaysa Marinho
Eratyrus mucronatus Stål, 1859 is a wild triatomine vector of Trypanosoma cruzi Chagas, 1909. However, little is known regarding the biology and ecoepidemiology of this triatomine in the Brazilian Amazon. The present study describes the biology of E. mucronatus grown under laboratory conditions and the epidemiological aspects of its natural breeding sites. Five colonies were monitored in the field for 3 years. Temperature and humidity measurements were taken in the mornings and afternoons at the natural breeding sites, and the behavior and distribution of the nymphs and adults were observed in the wild colony. We also monitored the life cycle under controlled laboratory conditions. Some factors that were considered decisive for the establishment of these colonies were present at all of the colonies studied in the field. These factors included an active termite nest, a vertebrate for repast, and dry and shaded substrates with temperatures of 24-28°C and with humidity of 80-90%. A generation was developed in 274 days under these microclimatic conditions in the laboratory. The climatic variables described in the field indicate that these environmental parameters have a limiting effect on the dispersal and colonization of E. mucronatus to new environments. In addition, the long period of development to adulthood demonstrates that only one generation can develop per year even under the more favorable laboratory conditions.
Leandro José Ramos
Full Text Available Abstract INTRODUCTION The occurrence of Triatoma sordida in the Brazilian Western Amazon is reported for the first time. METHODS Triatoma sordida specimens were collected from a Gallus gallus nest in a peridomiciliary area of Senador Guiomard municipality in the state of Acre. RESULTS The number of triatomine species in Acre increased from six to seven with this first report of T. sordida in the Brazilian Western Amazon. CONCLUSIONS The occurrence of T. sordida in Acre is of concern since it is among the most captured triatomines in peridomiciliary environments in Brazil, and carries a high potential for vector transmission.
Mendonça, Vagner José; de Oliveira, Jader; Rimoldi, Aline; Filho, Júlio C R Ferreira; de Araújo, Renato Freitas; da Rosa, João Aristeu
Triatomine surveillance in rural areas, artificial ecotypes, and natural ecotopes of the cities of Caturama, Ibipitanga, Macaúbas, and Seabra in the south-central region of the Brazilian state of Bahia was carried out between 2008 and 2013. Natural infection by Trypanosoma cruzi was evaluated in the specimens collected to monitor vectors of Chagas disease. A total of 1,357 specimens were collected, and four species were identified: Triatoma sordida (83%), Triatoma lenti (16.4%), Triatoma pseudomaculata (0.5%), and Panstrongylus geniculatus (0.1%). Triatoma sordida was found in four cities, only 0.7% in intradomiciliary environments. Triatoma lenti was found only in Macaúbas; 8.5% were found in intradomiciliary environments, 88.3% in peridomiciliary environments, and 3.1% in sylvatic environments. Natural infection by T. cruzi was 0.5% for T. sordida and 3.1% T. lenti. All of these cases were found in peridomiciliary environments of Macaúbas. As the results show, triatomines were found in intradomiciliary environments in three cities that were surveyed in the south-central region of the state of Bahia. Thus, an epidemiologic survey should be performed to avoid the risk of transmission to the population. © The American Society of Tropical Medicine and Hygiene.
Dalva A. Mello
Full Text Available In the present paper the life cycle of Rhodnius neglectus was studied. The mean length from egg to adult was 119 days. The mean length in day from each stage was: 17.4 (± 1.15 for first, 18.2 (± 1.28 for second, fourth and 29.8 (± 1.46 for fifth.
Full Text Available A total of 797 specimens of wild adult triatomines, belonging to six species from the entomological collections of the Costa Rican National Biodiversity Institute, was studied from the standpoint of their relative abundance, as reflected by light traps, distribution in the country, seasonal variations and climatic and altitudinal preferences. Triatoma dimidiata was the most abundant species (32.9% of the total specimens, with a very extensive distribution in different ecological zones, being more common between 100 to 400 m above sea level mainly at the end of the dry season. T. dispar was the third in frequency (21.5%, with narrower distribution, more abundant between 600 to 800 m and scarce during the dry season. Panstrongylus geniculatus and P. rufotuberculatus, second and fourth in frequency (22.1% and 15.1%, respectively, were widely distributed on both the Pacific and Caribbean basins, the former being more common between 80 to 270 m all year round and the latter below 800 m mainly during the first semester. Eratyrus cuspidatus which represented only 4.9% of the insects, was also present on both basins mainly below 200 m with a tendency to be scarce during certain months of the year, and was found in all types of ecological zones. Finally, Rhodnius pallescens, the least abundant species (3.6% was restricted to very humid areas below 20 m, on the north side and Caribbean basin. With the exception of R. pallescens, males were more commonly found than females. Some epidemiological implications related to the six species are discussed.
Gerardo A. MARTI
Full Text Available Se brinda un listado de especies del género Pimeliaphilus Trägårdh asociadas a diferentes especies de triatominos, con sus respectivas coordenadas geográficas de todo el continente americano. Se realizaron viajes de campo para incorporar nuevos registros a una recopilación bibliográfica. Se extiende la distribución geográfica de Pimeliaphilus triatomae Cunliffe, con dos registros para la provincia de Chaco (Argentina y se amplía el rango de hospedadores ya que se citan por primera vez asociados a Triatoma delpontei Romaña & Abalos.
Laura Cristina Lima Diniz
Em Triatoma infestans ainda não há pesquisas de isolamento de Peptídeos Antimicrobianas e como têm contato muitos microrganismos acreditamos que eles produzem esses componentes antimicrobianos. Neste estudo identificamos quatro peptídeos antimicrobianos principais. Os Tin-TK-I e Tin-TK-II que são similares com Taquicininas de insetos, não são hemolíticos e ativos contra três bactérias e três fungos, e são capazes de lisar membranas. Tin-TK-I é degradado por aminopeptidases e tem estrutura r...
Cuba Cuba, César Augusto; Vargas, Franklin; Roldan, Judith; Ampuero, Cynthia
Two passive methods in the assessment of intradomiciliary infestation by Rhodnius ecuadoriensis were tested: (i) the Gomes Nu ez sensor box (GN), (ii) sheets of white typing paper and (iii) one active timed manual method. The study was carried out in the Alto Chicama River Valley, Province of Gran Chim , Department of La Libertad. The study design consisted of an initial searching of triatomines inside of the domestic environment by the manual capture active procedure (man/hour) covering all the studied houses. Then, matched pairs of GN boxes and paper sheets were simultaneously installed in the bedrooms of 207 households distributed in 19 localities. A comparative prospective trial of these passive detection devices were monitored at 2, 4 and, finally 6 months follow-up. Parasitological Trypanosoma rangeli and/or T. cruzi infections were investigated in two houses with high level of infestation by R. ecuadoriensis. 16.9% of the 207 households investigated by an initial active manual method were infested with R. ecuadoriensis. The proportion of infested houses fluctuated from 6.2 to 55.5% amongst the 19 localities investigated. T. rangeli natural infection was detected in R. ecuadoriensis specimens collected in two households. Parasite rates in the bugs ranged from 16.6 to 21.7% respectively. The most striking fact was an average rate of salivary gland infection ranging from 7.4 to 8.3%. At the end of the sixth month period, a cumulative incidence of 31.4% of positive GN boxes against 15.9% for paper sheets was recorded. All three methods combined detected domestic infestation in 129 (62.3%) of the 207 houses studied in the 19 localities. The range of houses infested varies from 6.7% to 92.9%. In areas with low bug density infestation rates, the methodology experienced in our studies, seems to be the best choice for investigations on domestic R. ecuadoriensis populations.
Anita G Villacís
Full Text Available Rhodnius ecuadoriensis is the second most important vector of Chagas Disease (CD in Ecuador. The objective of this study was to describe (and compare the life cycle, the feeding and defecation patterns under laboratory conditions of two populations of this specie [from the provinces of Manabí (Coastal region and Loja (Andean region]. Egg-to-adult (n = 57 development took an average of 189.9 ± 20 (Manabí and 181.3 ± 6.4 days (Loja. Mortality rates were high among Lojan nymphs. Pre-feeding time (from contact with host to feeding initiation ranged from 4 min 42 s [nymph I (NI] to 8 min 30 s (male; feeding time ranged from 14 min 45 s (NI-28 min 25 s (male (Manabí and from 15 min 25 s (NI-28 min 57 s (nymph V (Loja. The amount of blood ingested increased significantly with instar and was larger for Manabí specimens (p < 0.001. Defecation while feeding was observed in Manabí specimens from stage nymph III and in Lojan bugs from stage nymph IV. There was a gradual, age-related increase in the frequency of this behaviour in both populations. Our results suggest that R. ecuadoriensis has the bionomic traits of an efficient vector of Trypanosoma cruzi. Together with previous data on the capacity of this species to infest rural households, these results indicate that control of synanthropic R. ecuadoriensis populations in the coastal and Andean regions may have a significant impact for CD control in Ecuador and Northern Peru.
Full Text Available Triatoma nitida is a wild species occurring in Mexico and Central America. In order to establish the length of its life cycle and transmission potential, the following parameters were observed: the incubation period, the interval between hatching, or moulting, and the first feeding; the number of blood meals and the time of development. The time-lapse before the bite, the length of feeding and the interval between the end of the blood meal and defecation, as well as the site of defecation were also analyzed. Average length of the egg incubation period was 18.2 days. Time interval between the food source offering and the bite was less than 4 min in 60//of the analyzed cases, except in the fifth instar, where only 38//of the insects began feeding in less than 5 min. The blood-sucking period was long and rising until the fifth instar, decreasing in adults, and ranging from 1 min to 2 and a half hours. Only 26//of the blood meals were followed by defecations within 20 min. The average length of the life cycle was 897.5 days.
Full Text Available Foram estudadas as genitálias externas masculinas das cinco espécies que constituem o complexo phyllosoma: Triatoma phyllosoma (Burmeister, 1835, T. pallidipennis (Stal, 1872, T. longipennis Usinger, 1939, T. picturata Usinger, 1939 e T. mazzottii Usinger, 1941, todas encontradas naturalmente infectadas pelo Trypanosoma cruzi, e, com exceção de T. picturata, colonizando no domicílio humano. São espécies muito próximas, não só pelo aspecto externo, como pela área geográfica onde ocorrem, a região ocidental do México. As estruturas constituintes dessas genitálias foram analisadas comparativamente, com o intuito de ampliar o estudo das aludidas espécies, criando informações morfológicas adicionais à taxonomia atualmente aceita. Foram evidenciadas quatro estruturas no edeago: falosoma, suporte da falosoma, processo do endosoma e vesica; uma no aparelho articular, o processo do gonoporo; e outra no pigóforo, o processo do pigóforo. Essas estruturas apresentam pequenas variações no tamanho e na forma, acentuando a proximidade das espécies entre si e a dificuldade existente para a compreensão perfeita do status taxonômico de cada uma. O trabalho completar-se-á com a discussão dos já conhecidos aspectos morfológicos externos e os evidenciados pela morfologia das genitálias.A study was made of the male genitalia of five species which constitute the phyllosoma complex: Triatoma phyllosoma (Burmeister, 1835, T. pallidipennis (Stal, 1872, T. longipennis Usinger, 1939, T. picturata Usinger, 1939 and T. mazzottii Usinger, 1941; all of them were found naturally infected by Trypanosoma cruzi, and, except T. picturata colonizing human houses. These species are very similar, not only by the external aspects but also by their geographical occurence in Mexico. The structures which constitute these genitalias were analysed comparatively with the intention to increase the knowledge of the mentioned species, showing some morphological informations to the modern taxonomy. There were identified four aedeagus structures: phallosoma, struts, endosoma and vesica processes; one on articulatory apparatus, the gonopore process; and other on pygophore, the pygophore process. These structures show small variations in size and shape, emphasizing the relatioship between the species and the dificulty to the perfect understanding of the taxonomic status of each one.
Entomological Indices, Feeding Sources, and Molecular Identification of Triatoma phyllosoma (Hemiptera: Reduviidae) One of the Main Vectors of Chagas Disease in the Istmo de Tehuantepec, Oaxaca, Mexico
Villalobos, Guiehdani; Martínez-Hernández, Fernando; de la Torre, Patricia; Laclette, Juan Pedro; Espinoza, Bertha
The purpose of this study was to conduct an entomological analysis, determination of feeding sources, and molecular identification of triatomines in five communities of the Istmo de Tehuantepec, Oaxaca. The only found species in two of five searched communities (San Mateo del Mar and Tehuantepec City) was Triatoma phyllosoma. Colonization indices were high in both communities. In San Mateo del Mar, the insects were found indoors and in Tehuantepec City in peridomestic areas. The Trypanosoma cruzi infection indices were 2.1% in San Mateo del Mar and 39.4% in Tehuantepec City. This difference could be related to the high numbers of triatomine feeding on hens in the former community. In contrast, in Tehuantepec, dogs were the principal triatomine feeding sources. All nymphs and adults that were genetically analyzed belonged to the species T. phyllosoma. Low levels of genetic variation were found between vectors from both communities. PMID:21896810
Flores-Villegas, A Laura; Cabrera-Bravo, Margarita; Toriello, Conchita; Bucio-Torres, Martha I; Salazar-Schettino, Paz María; Córdoba-Aguilar, Alex
Chagas disease is a key health problem in Latin America and is caused and transmitted by Trypanosoma cruzi and triatomine bugs, respectively. Control of triatomines has largely relied on the use pyrethroids, which has proved to be ineffective in the long term. Alternatively, the use of entomopathogenic fungi has been implemented to control triatomine bugs. These fungi are highly efficient as they induce a reduction in immune response on insects. Meccus pallidipennis is the main triatomine vector of Chagas disease in Mexico. In this work we investigated the effects of two entomopathogenic fungi, Metarhizium anisopliae and Isaria fumosorosea, on M. pallidipennis nymphs in terms of insect survival and immune response. We had an infected and a control group for each fungal species and assessed: a) insect survival during 30 days; and, b) phenoloxidase (PO) and prophenoloxidase (proPO; two key traits in insect immune response) at 24, 48, 96 and 144 h. For survival we used Kaplan-Meier survival analysis while for immune response we used factorial, repeated-measures ANOVA for each fungal species. Animals treated with M. anisopliae died sooner than animals treated with I. fumosorosea. Infected animals showed lower PO and proPO values than sham individuals, with a clear decrease in these parameters at 24 h with no further changes after this time. Our study widens the possibility of entomopathogenic fungi being used for triatomine control. The negative effect on PO and proPO seems mediated by a down-regulation of the triatomine immune response.
Oswaldo Paulo Forattini
Full Text Available Assinala-se o encontro de focos naturais do Triatoma arthurneivai Lent e Martins, 1940, na localidade de Itupararanga, Município de Votorantim, no Estado de São Paulo. Os ecótopos apresentaram as mesmas características já assinaladas anteriormente em regiões vizinhas, ou sejam, as de espaços localizados entre lascas de pedras de «granito róseo». O triatomíneo apresentou-se associado com lagartos Tropidurus torquatus Wied. mas, no laboratório, mostrou acentuada avidez por sangue de camundongos albinos. Por outro lado, a infecção experimental com Trypanosoma cruzi (cêpa F-1 foi obtida com facilidade. Em vista dos dados coletados, os autores permitem-se tecer considerações sôbre a possibilidade desse hemíptero vir a desempenhar algum papel transmissor, na natureza.An area with natural foci of Triatoma arthurneivai Lent & Martins, 1940, is recorded at the place of Itupararanga in the county of Salto de Pirapora, São Paulo State, Brasil. These foci were represented by ecotopes placed between sliced stones, similar to the ones previously described in surrounding regions. An association with lizards Tropidurus torquatus Wied. it was suspected to be of feeding nature. Nevertheless the triatomids showed to eat quickly and intensively white mice, under laboratory conditions. Beside this, the experimental infection by Trypanosoma cruzi was easily obtained. These data led the authors to suspect that T. arthurneivai may play some transmission role in nature.
Colin Favret; Nathan P. Havill; Gary L. Miller; Masakazu Sano; Benjamin Victor
A taxonomic and nomenclatural Catalogue of the adelgids (Hemiptera: Adelgidae) is presented. Six family-group names are listed, five being synonyms of Adelgidae. Twenty-two genus-group names, of which nine are subjectively valid and in use, are presented with their type species, etymology, and grammatical gender. One hundred and six species-group names are listed, of...
A taxonomic and nomenclatural catalog of the adelgids (Hemiptera: Adelgidae) is presented. Six family-group names are listed, five being synonyms of Adelgidae. Twenty-two genus-group names, of which nine are valid and in use, are presented with their type species, etymology, and grammatical gender. ...
In Petri dish assays, fumigation of a pyrethroid-susceptible strain of bed bugs Cimex lectularius L. (Hemiptera: Cimicidae) with various essential oils resulted in mortality that approached or equaled 100%, after 5 days. However, when bed bugs were exposed to the same essential oils in sealed, comme...
Ann M. Lynch
Elatobium abietinum Walker is a spruce-feeding aphid that in Europe is referred to as the green spruce aphid (Day et al., 1998a) (Fig. 1). However, in North America E. abietinum is known simply as the spruce aphid, while the common name "green spruce aphid" refers to a different species, Cinara fornacula Hottes (Hemiptera: Aphididae) (http://www.entsoc.org/...
Alevi, K C C; Ravazi, A; Mendonça, V J; Rosa, J A; Azeredo-Oliveira, M T V
The Triatominae subfamily comprises 6 tribes. The tribe Rhodniini comprises 2 genera and 22 nominal species. Rhodnius montenegrensis (Hemiptera, Triatominae) was recently described as evolutionarily related to R. robustus. Therefore, in order to contribute to karyosystematic study of the tribe Rhodniini, this report describes the number of chromosomes and compares the karyotype of R. montenegrensis to that of all other species in the tribe, in order to determine the karyotypic evolution of the tribe Rhodniini. The seminiferous tubules of adult males, after being removed and fixated on a cover slip, were processed with lacto-aceto-orcein for cytogenetic analysis. R. montenegrensis, as well as all other species of the tribe Rhodniini showed 22 chromosomes (20 autosomes + XY). Thus, we hereby describe the karyotype of the species R. montenegrensis and mainly highlight that the tribe Rhodniini displays karyotypic homogeneity, demonstrating itself as a derived group to a lesser extent when compared to the number of chromosomes of the common ancestors of the subfamily Triatominae.
Full Text Available Se estudió el comportamiento reproductivo y de defecación de Triatoma maculata (Erichson 1848alimentando artificialmente con sangre humana.Los estadios II y III mostraron mayor frecuencia de defecaciones (ID=0.6 n=40,el estadio V no alcanzó la diferenciación sexual, la fertilidad fue 55%(n=865,fecundidad 8 huevos/hembra/semana (n=26,22 días de desarrollo embrionario (n=477,longevidad de hembras 51 días (n=26,el tiempo intermuda aumenta progresivamente desde 35 días en el estadio I hasta 46 días en el estadio IV,el porcentaje de muda varió desde 0%en el estadio V hasta 63%en el estadio III,la mortalidad varió desde 8%en el estadio III hasta 100%en el estadio V (n=40.Los resultados del presente trabajo aportan evidencias que explican la menor capacidad vectorial y la baja densidad de T.maculata en el domicilio humano.Defecation index and reproductive success of Triatoma maculata (Hemiptera: Reduviidae under laboratory conditions.The reproductive and defecating behavior of Triatoma maculata (Erichson 1848was studied on animals from an university culture in Venezuela.This species does not reach the importance of Rhodnius prolixus Stal 1859 as Chagas disease vector in Venezuela.This study addressed the role of defecating frequency,an index of how dangerous the animals are for the human population,and its relationship with why T.maculata is a less important vector than R.prolixus .Human blood was fed to the insects through an artificial feeding device.The 2nd and 3rd instar nymphs defecated more frequently (Id=0.6,n=40,and our Vth instar nymphs did not complete sexual differentiation.Fertility was 55%(n=865and fecundity 8 eggs/female/week (n=26. Egg incubation lasted 22 days (n=477.Female longevity was 51 days (n=26.Intermould time grew progressively from 35 days for 1st to 40 days for 4th instar nymphs (n=40.Mould percentage varied from 0% for Vth to 63%for 3rd instar nymphs.Mortality varied from 8% for 3rd to 100% for Vth instar nymphs
Favret, Colin; Havill, Nathan P; Miller, Gary L; Sano, Masakazu; Victor, Benjamin
A taxonomic and nomenclatural Catalogue of the adelgids (Hemiptera: Adelgidae) is presented. Six family-group names are listed, five being synonyms of Adelgidae. Twenty-two genus-group names, of which nine are subjectively valid and in use, are presented with their type species, etymology, and grammatical gender. One hundred and six species-group names are listed, of which 70 are considered subjectively valid.
Favret, Colin; Blackman, Roger L; Miller, Gary L; Victor, Benjamin
A taxonomic and nomenclatural catalog of the phylloxerids (Hemiptera, Phylloxeridae) is presented. Six family-group names are listed, three being synonyms. Thirty-five genus-group names, of which six are subjectively valid, are presented with their type species, etymology, and grammatical gender. Ninety-four species-group names are listed, of which 73 are considered subjectively valid. This is the last group of Aphidomorpha to be catalogued, bringing the list of valid extant species to 5,218.
Rakitov, Roman; Gorb, Stanislav N.
Leafhoppers (Insecta, Hemiptera, Cicadellidae) actively coat their integuments with buckyball-shaped submicron proteinaceous secretory particles, called brochosomes. Here, we demonstrate that brochosomal coats, recently shown to be superhydrophobic, act as non-stick coatings and protect leafhoppers from contamination with their own sticky exudates—filtered plant sap. We exposed 137 wings of Alnetoidia alneti (Dahlbom), from half of which brochosomes were removed, to the rain of exudates under...
Full Text Available Melucha grandicula sp. n. and M. perampla sp. n., (Hemiptera: Heteroptera: Coreidae: Coreinae: Nematopodini are described from Bolivia, Colombia, Paraguay and Peru. Melucha quadrivittis Stål, 1862, stat. restit., is resurrected from synonymy under M. phyllocnemis (Burmeister, 1835. Melucha ruficornis Breddin, 1903, syn. n., is synonymized under M. lineatella (Fabricius, 1803. An identification key for the known species of Melucha Amyot & Serville, 1843 is given. New distributional records for some previously known species are added.
A Triatoma maculata (Hemiptera, Reduviidae, Triatominae population from Roraima, Amazon region, Brazil, has some bionomic characteristics of a potential Chagas disease vector Uma população de Triatoma maculata (Hemiptera, Reduviidae, Triatominae proveniente de Roraima, Amazônia, Brasil, possui algumas características bionômicas de vetor potencial de doença de Chagas
José Francisco Luitgards-Moura
Full Text Available Even though Chagas disease is rare in the Brazilian Amazon, the conditions for the establishment of domiciliated cycles prevail in many areas where triatomines are of frequent occurrence. In Roraima, a previous serological and entomological survey in three agricultural settlements showed the existence of all transmission cycle elements, i.e., individuals infected by Trypanosoma cruzi, triatomine species previously found harboring T. cruzi in the broader Amazon region of neighboring countries and, domicile/ peridomicile conditions favorable to triatomine colonization. Triatoma maculata was the most frequent species, found in chicken houses in the peridomicile and sporadically within residences. Aiming to investigate the possibility of T. maculata to possess the potentiality to transmit T. cruzi in the area, bionomic characteristics were studied under laboratory conditions. These were feeding frequency, time for defecation after a blood meal, time elapsed in voluntary fasting pre- and pos-ecdysis, moulting time periods, pre-oviposition and oviposition periods and index of oviposition, incubation period, egg viability, longevity and mortality rate. Results show that the Passarão population of T. maculata should be considered a potential vector of T. cruzi since it shows a capacity to infest artificial ecotopes in the peridomicile, to carry out large number of meals during the nymphal cycle, to have a relatively short developmental cycle capable of producing 2.9 generations/year, to blood source eclecticism, to defecate immediately after the blood meal while still on the host and to the fact that has been previously found naturally infected by T.cruzi.A doença de Chagas é de rara ocorrência na Região Amazônica Brasileira, onde contudo as condições para o estabelecimento de ciclos domésticos existem. Um estudo previamente realizado em áreas de colonização agrícola no Estado de Roraima, mostrou a possibilidade de ciclos autóctones de transmissão virem a ocorrer uma vez que todos os elementos estavam lá presentes, indivíduos infectados por Trypanosoma cruzi, espécies de triatomíneos anteriormente descritas como infectadas por T. cruzi na Região Amazônica de países fronteiriços e, ambientes domiciliares e peri-domiciliares favoráveis à colonização de triatomíneos. Triatoma maculata foi a espécie mais frequentemente encontrada, tendo sido coletada em galinheiros no peridomicílio e esporadicamente nos domicílios. Visando investigar a potencialidade de T. maculata como espécie vetora na área, algumas características bionômicas foram estudadas em condições de laboratório incluindo freqüência de alimentação, tempo de defecação pós-prandial, tempo de jejum voluntário na pré- e na pós-ecdise, período inter-mudas, períodos de pré-oviposição e de oviposição, índice de oviposição, período de incubação, viabilidade dos ovos, índices de longevidade e de mortalidade. Os resultados mostraram que a população de T. maculata da Colônia Agrícola do Passarão deve ser considerada vetora em potencial do T. cruzi uma vez que mostrou capacidade de infestar ecótopos artificiais no peridomicílio, de se alimentar com freqüência durante o período ninfal, de possuir um ciclo de desenvolvimento relativamente curto com 2,9 gerações/ano, de possuir hábitos ecléticos de alimentação, de defecar imediatamente após a hematofagia quando ainda no hospedeiro e devido ao fato de ter sido previamente encontrada infectada por T. cruzi.
Primeiro registro de Saica apicalis Osborn & Drake para o Brasil e Pseudosaica florida (Barber, com notas taxonômicas e chave para os gêneros de Saicinae do Brasil (Hemiptera, Reduviidae First records of Saica apicalis Osborn & Drake and Pseudosaica florida (Barber in Brazil, with taxonomical notes and key for the Saicinae genera of Brazil (Hemiptera, Reduviidae
Hélcio R. Gil-Santana
Full Text Available Apresenta-se o primeiro registro de ocorrência de Saica apicalis Osborn & Drake, 1915 e de Pseudosaica florida (Barber, 1953 no Brasil. Notas taxonômicas sobre Saica Amyot & Serville, 1843 e Pseudosaica Blinn, 1990 são fornecidas.The first records of Saica apicalis Osborn & Drake, 1915 and Pseudosaica florida (Barber, 1953 for Brazil are presented. Taxonomical notes on Saica Amyot & Serville, 1843 and Pseudosaica Blinn, 1990 are given.
Biologia do Triatoma vitticeps (Stal, 1859 em condições de laboratório (Hemiptera: Reduviidae: Triatominae: II. Resistência ao jejum Biology of Triatoma vitticeps (Stal, 1859 under laboratory conditions (Hemiptera: Reduviidae: Triatominae: II. Resistance to starvation
Teresa Cristina M. Gonçalves
Full Text Available Em prosseguimento ao estudo da biologia do Triatoma vitticeps (Gonçalves et al., 1988, foram feitas observações sobre a sua resistência ao jejum. Dos 286 ovos obtidos, apenas 201 eclodiram e atingiram o estádio pretendido para as observações. Os demais não eclodiram, não completaram a muda ou morreram sem motivo aparente. As ninfas foram acondicionadas, individualmente em frascos de Borrel, devidamente registrados. Para a alimentação foram utilizados camundongos e a medida que as ninfas atingiam o estágio pretendido a alimentação era suspensa até ocorrer a morte. A avaliação da resistência ao jejum foi feita da seguinte forma: o intervalo de dias entre o último repasto e a morte e entre a muda e a morte. Verificou-se que a resistência está diretamente relacionada com a fase de desenvolvimento. Para os parâmetros último repasto/morte e muda/morte, ambos os sexos foram menos resistentes do que as ninfas de 3º e 2º estádios, respectivamente. O experimento teve duração de 15 meses e neste período as temperaturas máxima e mínima e a umidade relativa do ar variaram em média de 25 ± 2ºC e 81 ± 3% UR, respectivamente. O material foi proveniente da criação de triatomíneos mantida no Departamento de Entomologia do Instituto Oswaldo Cruz.Following the study on the biology of Triatoma vitticeps (Gonçalves et al. 1988 observations have been made on its resistance to starvation. Of the 286 eggs obtained only 201 hatched and reached the intended stage for observation. The others did not eclode, neither reached the ecdisis nor died, without explanation. The nymphs were kept, separately, in Borrel flasks and properly listed. The blood-meal was performed in mice, although the insects were kept without feeding as soon as moulted. The starvation was evaluated in two ways: the time-lapse in days between the last meal/death and between mult/death. The starvation was directly related with the developmental stage. In relation to the parameters las meal/death and moult/death, both sexes were less resistant than 3rd and 2nd stage, respectively. The experiment have been carried out for 15 months and by this time the average minimum and maximum temperatures and the humidity were 25 ± 2ºC and 81 ± 3% UR, respectively. The material spent belongs to the triatomine colony of the Oswaldo Cruz Institut Department of Entomology.
Monitoramento da suscetibilidade de populações de Triatoma sordida Stål, 1859 (Hemiptera: Reduviidae ao inseticida deltametrina, na região Centro-Oeste do Brasil Monitoring the susceptibility of Triatoma sordida Stål, 1859 (Hemiptera: Reduviidae to deltamethrin insecticide, in Central-Western Brazil
Marcos Takashi Obara
Full Text Available INTRODUÇÃO: Populações de Triatoma sordida Stål, 1859 foram investigadas quanto à suscetibilidade à deltametrina. MÉTODOS: Análise por meio de bioensaios por aplicação tópica em 11 populações de T. sordida procedentes dos Estados de Goiás, Mato Grosso e Mato Grosso do Sul. RESULTADOS: As estimativas de DL50 e RR50 demonstraram elevados níveis de suscetibilidade (DL50 INTRODUCTION: Triatoma sordida Stål, 1859 populations were investigated for susceptibility to deltamethrin. METHODS: This study aimed to analyze the resistance of 11 populations of insects from the States of Goiás, Mato Grosso and Mato Grosso do Sul by topical application bioassays. RESULTS: The estimated LD50 and RR50 showed high levels of susceptibility (LD50 < 1 and RR50 < 2. However, analysis of the slope of the dose response curve showed that the populations of insects in the towns of Firminópolis/GO, Posse/GO, Poxoréu/MT, Douradina/MS and Aparecida do Taboado/MS present great probability of evolving resistance and, thus, are more likely to tolerate treatment with deltamethrin. CONCLUSIONS: Small changes in susceptibility and low levels of resistance were detected, but the temporal changes of susceptibility should be continuously monitored to adequately guide the actions of vector-control of DC.
Susceptibilidade de Rhodnius neglectus, Rhodnius robustus e Triatoma infestans (Hemiptera, Reduviidae, Triatominae à infecção por duas cepas de Trypanosoma cruzi (Kinetoplastidae, Trypanosomatidae utilizando xenodiagnóstico artificial Susceptibility of Rhodnius neglectus, Rhodnius robustus and Triatoma infestans (Hemiptera, Reduviidae, Triatominae to two Trypanosoma cruzi strains infection (Kinetoplastidae, Trypanosomatidae using artificial xenodiagnosis
Luciamáre Perinetti Alves Martins
Full Text Available A susceptibilidade de ninfas de 3º estádio de Rhodnius neglectus, R. robustus e Triatoma infestans às cepas Y e AMJM de Trypanosoma cruzi foi verificada utilizando xenodiagnóstico artificial. Para a leitura do xenodiagnóstico, as fezes dos triatomíneos foram examinadas a cada dois dias, a partir do 5º até o 31º dia pós infecção, pela técnica de compressão abdominal. Os resultados mostraram diferenças na susceptibilidade dos triatomíneos para as duas cepas estudadas e o período ótimo de leitura variou do 11º ao 19º dias para a cepa Y e do 11º ao 15º dias para a cepa AMJM. Também, pôde-se concluir que para a cepa Y, as três espécies de triatomíneos demonstraram boa susceptibilidade, enquanto para a cepa AMJM, a melhor susceptibilidade foi observada com R. neglectus, seguida pelo T. infestans e R. robustus.The susceptibility of 3rd instar nymph of Triatominae Rhodnius neglectus, R. robustus and Triatoma infestans to Trypanosoma cruzi Y and AMJM strains was verified using artificial xenodiagnosis. After the accomplishment of the xenodiagnosis, the faeces of the Triatominae were analyzed on two-day intervals from day 5 until day 31 post infection, using the abdominal compression technique. The results showed differences in the susceptibility of the Triatominae for the two strains studied, and the optimal period reading differed from day 11 to day 19 for the Y strain and from day 11 to day 15 for the AMJM strain. For the Y strain, all three Triatominae species showed good susceptibility, whereas in the AMJM strain, the highest susceptibility was observed with R. neglectus, followed by T. infestans and R. robustus.
A genitália externa dos machos de sete espécies de Triatoma Laporte, 1832 da região Neártica (Hemiptera, Reduviidae, Triatominae Male external genitalia in seven species of Triatoma Laporte, 1832 from neartic region (Hemiptera, Reduviidae, Triatominae
Full Text Available Sete espécies da região neártica: Triatoma barberi Usinger, 1939; T. rubida (Uhler, 1894; T. gertaeckeri (Stal, 1859; T. lecticularia (Stal, 1859; T. protracta (Uhler, 1894; T. recurva (Stal, 1868 e T. sanguisuga (Leconte, 1855 foram analisadas comparativamente, tendo como enfoque as estruturas da genitália do macho: falosoma (Ph, suporte do falosoma (SPh, processo do endosoma (PrEn, vesica (V e aparelho articular (Apb. As estruturas fálicas se mostraram capazes de serem usadas como critério morfológico suplementar aos padrões atualmente usados, em taxonomia. Estas espécies silvestres são encontradas nos Estados Unidos e México, naturalmente infectadas pelo T. cruzi; algumas vivem no perdomicílio e outras eventualmente no domicílio, sem contudo colonizá-lo.Seven species from the neartic region, Triatoma barberi Usinger, 1939; T. rubida (Uhler, 1894; T. gerstaeckeri (Stal, 1859; T. lecticularia (Stal, 1859; T. protracta (Uhler, 1894; T. recurva (Stal, 1868 and T. sanguisuga (Leconte, 1855 were comparatively analysed with emphasis on the genital structures of the male bug: the phallosome (Ph, the phallosome struts (SPh, the endosoma process (PrEn, the vesica (V and the articulatory apparatus (Apb. The phallic structures were useful as a supplementary morphological criterion to the present taxonomical standards. These wild species are found naturally infected by Trypanosoma cruzi in the United States and Mexico. Some of them live outside human dwellings while other are occasionally domiciliary, although they do not colonize these homes.
Ming-Xing, Lu; Zhi-Teng, Chen; Wei-Wei, Yu; Yu-Zhou, Du
We report the complete mitochondrial genome (mitogenome) of a spiraling whitefly, Aleurodicus dispersus (Hemiptera: Aleyrodidae). The 16 170 bp long genome consists of 13 protein-coding genes, 20 transfer RNAs, 2 ribosomal RNAs, and a control region. The A. dispersus mitogenome also includes a cytb-like non-coding region and shows several variations relative to the typical insect mitogenome. A phylogenetic tree has been constructed using the 13 protein-coding genes of 12 related species from Hemiptera. Our results would contribute to further study of phylogeny in Aleyrodidae and Hemiptera.
Samita Limbu; Katie Cassidy; Melody Keena; Patrick Tobin; Kelli Hoover
Scymnus (Neopullus) camptodromus Yu and Liu (Coleoptera: Coccinellidae) was brought to the United States from China as a potential biological control agent for hemlock woolly adelgid (Adelges tsugae Annand) (Hemiptera: Adelgidae). Scymnus camptodromus phenology is...
Samita Limbu; Melody A. Keena; David Long; Nancy Ostiguy; Kelli. Hoover
Development time and prey consumption of Scymnus (Neopullus) camptodromus Yu and Liu (Coleoptera: Coccinellidae) larvae by instar, strain, and temperature were evaluated. S. camptodromus, a specialist predator of hemlock woolly adelgid Adelges tsugae (Annand) (Hemiptera:...
Wang, Yan-hui; Cui, Ying; Rédei, Dávid
Heteroptera are among the most diverse hemimetabolous insects. Seven infraorders have been recognized within this suborder of Hemiptera. Apart from the well-established sister-group relationship between Cimicomorpha and Pentatomomorpha (= Terheteroptera), the two terminal lineages...
Proper identification of mealybugs (Hemiptera: Pseudococcidae) require preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare mealybug specimens on microscope slides for examination and identification. Steps ranging from collection, spec...
Proper identification of armored scales (Hemiptera: Diaspididae) requires preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare armored scales specimens on microscope slides for examination and identification. Steps ranging from collect...
Proper identification of whiteflies (Hemiptera:Alyrodidae) requires preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare whitefly specimens on microscope slides for examination and identification. Steps ranging from collection, specimen...
Proper identification of aphids (Hemiptera: Aphididae) require preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare aphid specimens on microscope slides for examination and indentification. Steps ranging from collection, specimen clear...
Proper identification of aphids, scale insects, psyllids, and whitefles (Hemiptera: Sternorrhyncha) require preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare sternorrhynchous specimens on microscope slides for examination and identi...
Limbu, Samita; Cassidy, Katie; Keena, Melody; Tobin, Patrick; Hoover, Kelli
Scymnus (Neopullus) camptodromus Yu and Liu (Coleoptera: Coccinellidae) was brought to the United States from China as a potential biological control agent for hemlock woolly adelgid (Adelges tsugae Annand) (Hemiptera: Adelgidae). Scymnus camptodromus phenology is closely synchronized with that of A. tsugae and has several characteristics of a promising biological control agent. As a prerequisite to field release, S. camptodromus was evaluated for potential nontarget impacts. In host range studies, the predator was given the choice of sympatric adelgid and nonadelgid prey items. Nontarget testing showed that S. camptodromus will feed to some degree on other adelgid species, but highly prefers A. tsugae. We also evaluated larval development of S. camptodromus on pine bark adelgid (Pineus strobi (Hartig)) (Hemiptera: Adelgidae) and larch adelgid (Adelges laricis Vallot) (Hemiptera: Adelgidae); a small proportion of predator larvae was able to develop to adulthood on P. strobi or A. laricis alone. Scymnus camptodromus showed no interest in feeding on woolly alder aphid (Paraprociphilus tessellatus Fitch) (Hemiptera: Aphididae) or woolly apple aphid (Eriosoma lanigerum (Hausmann)) (Hemiptera: Aphididae), and minimal interest in cotton aphid (Aphis gossypii Glover) (Hemiptera: Aphididae) in choice and no-choice experiments. Scymnus camptodromus females did not oviposit on any host material other than A. tsugae-infested hemlock. Under the circumstances of the study, S. camptodromus appears to be a specific predator of A. tsugae, with minimal risk to nontarget species. Although the predator can develop on P. strobi, the likelihood that S. camptodromus would oviposit on pine hosts of this adelgid is small.
Hu, Yanhong; Chen, Xiaoming; Yang, Pu
Abstract The transformation from embryo to first instar nymph is an essential process in the insect life cycle. In order to characterize protein expression in the Ericerus pela Chavannes (Hemiptera: Coccoidea) egg, high-throughput proteomics and bioinformatics methods were used. A total of 678 peptides were identified and assigned to 358 protein groups. The proteins exhibited a wide range of molecular weight (3.50–495.12 kDa) and isoelectric points (3.50–13.1). Gene Ontology annotation showed...
Duas EspÃ©cies de Cochonilhas (Hemiptera: Diaspididae Associadas com Soros de Samambaias Resumo. A presente comunicaÃ§Ã£o relata a presenÃ§a de duas espÃ©cies de cochonilhas Hemiberlesia palmae (Cockerell e Pinnaspis strachani (Cooley (Coccoidea, Diaspididae, associadas respectivamente com Asplenium serratum L. (Aspleniaceae e Niphidium crassifolium (L. Lellinger (Polypodiaceae. Ã‰ o primeiro registro de uma samambaia como planta hospedeira de Hemiberlesia palmae. Â Nas duas espÃ©cies de samambaias, os diaspidÃdeos encontravam-se concentrados principalmente ao redor dos soros.
Laroche, Maureen; Berenger, Jean-Michel; Mediannikov, Oleg; Raoult, Didier; Parola, Philippe
Among the Reduviidae family, triatomines are giant blood-sucking bugs. They are well known in Central and South America where they transmit Trypanosoma cruzi to mammals, including humans, through their feces. This parasitic protozoan is the causative agent of Chagas disease, a major public health issue in endemic areas. Because of the medical and economic impact of Chagas disease, the presence of other arthropod-borne pathogens in triatomines was rarely investigated. In this study, seven triatomines species involved in the transmission of T. cruzi were molecularly screened for the presence of known pathogens generally associated with arthropods, such as Rickettsia, Bartonella, Anaplasmataceae, Borrelia species and Coxiella burnetii. Of all included triatomine species, only Eratyrus mucronatus specimens tested positive for Bartonella species for 56% of tested samples. A new genotype of Bartonella spp. was detected in 13/23 Eratyrus mucronatus specimens, an important vector of T. cruzi to humans. This bacterium was further characterized by sequencing fragments of the ftsZ, gltA and rpoB genes. Depending on the targeted gene, this agent shares 84% to 91% of identity with B. bacilliformis, the agent of Carrion's disease, a deadly sandfly-borne infectious disease endemic in South America. It is also closely related to animal pathogens such as B. bovis and B. chomelii. As E. mucronatus is an invasive species that occasionally feeds on humans, the presence of potentially pathogenic Bartonella-infected bugs could present another risk for human health, along with the T. cruzi issue.
Coscarón, María Del Carmen; Basset, Carina; Lopez, Nancy
A checklist of Heteroptera type specimens deposited in the collection of División Entomología, Museo de La Plata. It harbours type material of 1153 species belonging to 37 families (Enicocephalidae, Schizopteridae, Gerridae, Veliidae, Hydrometridae, Naucoridae, Belostomatidae, Nepidae, Corixidae, Notonectidae, Pleidae, Saldidae, Cimicidae, Polyctenidae, Nabidae, Miridae, Tingidae, Vianaididae, Thaumastocoridae, Reduviidae, Aradidae, Alydidae, Coreidae, Rhopalidae, Berytidae, Blissidae, Lygaeidae, Oxycarenidae, Rhyparochromidae, Idiostolidae, Largidae, Pyrrhocoridae, Anthocoridae, Cydnidae, Pentatomidae, Scutelleridae, Thyreocoridae), represented by 207 holotypes, 26 allotypes, 578 paratypes, 1 lectotype, 1 paralectotype and 340 syntypes. For each taxon providing update information on valid names, categories of types, and locality.
Full Text Available The genus Apiococcus Hempel (Hemiptera, Eriococcidae, with redescription of two species. Apiococcus Hempel is a genus from Brazil composed of four gall-inducing species. The adult females of two species, Apiococcus globosus Hempel and A. singularis Hempel, from Brazil, are redescribed and illustrated. Keys to the species of the genus and their galls are given.
Wolff, V R S; Kondo, T; Peronti, A L B G; Noronha, A C S
Commercial cultivation of the fruit tree Myrciaria dubia (Myrtaceae) is being developed in Brazil but phytophagous insects, including scale insects (Hemiptera: Coccoidea), can become pests in plantations. The coccids Ceroplastes jamaicensis White, Coccus viridis (Green), Parasaissetia nigra (Nietner), Pseudokermes vitreus (Cockerell) (Coccidae), and the diaspidid Pseudaonidia trilobitiformis (Green) were collected on M. dubia in the municipality of Belém and Tomé-Açu, state of Pará (PA), metropolitan and Northeast Pará mesoregions, Brazil. A key to species of Coccoidea recorded on M. dubia, based on adult females, is provided. Photographs for all scale insects reported on M. dubia are provided. Ceroplastes jamaicensis is recorded for the first time for Brazil and is herein reported for the first time associated with this host.
Nafría, Juan M Nieto; Hidalgo, Nicolas Pérez; Brown, Paul A
Three new species of Hyadaphis Kirkaldy, 1904 (Hemiptera, Aphididae, Macrosiphini) are established: Hyadaphis levantina sp. n. from specimens caught on Lonicera nummulariifolia from Lebanon and Israel, and Hyadaphis anethi sp. n. plus Hyadaphis parva sp. n. from specimens respectively caught on Anethum sp. and Andrachne (?) cordifolia from Pakistan. Apterous viviparous females of all three species, alate viviparae of the first two and males of H. anethi are described. Known and new species of Hyadaphis are grouped for two relevant characters: (1) size and shape of siphunculi, and (2) host plant and life cycle; and the discriminant features of apterous viviparous females of the new species are compared with the already described species of the same group and a key for the Hyadaphis species is provided.
Alevi, K C C; Reis, Y V; Borgueti, A O; Mendonça, V J; Rosa, J A; Azeredo-Oliveira, M T V
Triatomines are insects that are taxonomically included in the Hemiptera order and Triatominae subfamily. Based on phenotypic similarity, capacity hybridization, and genetic and ecological aspects, the triatomine species can be grouped into specific complexes and subcomplexes. However, these groupings have not been confirmed. Cytogenetic analyses are important cytotaxonomic tools for improving the taxonomic knowledge of triatomines. Thus, we examined the karyotype of Triatoma baratai and compared the results with those of other species in the Matogrossensis subcomplex in order increase the understanding of vector potential. We also examined the cytotaxonomic classification of this insect. Triatoma baratai, similarly to other species that currently compose the Matogrossensis subcomplex, contains 22 chromosomes (20A + XY). Here, we describe the diploid chromosome set of T. baratai. We confirmed their current classification in the Matogrossensis subcomplex and demonstrated that the species in this subcomplex present karyotype homogeneity.
Laroche, Maureen; Berenger, Jean-Michel; Mediannikov, Oleg; Raoult, Didier; Parola, Philippe
Background Among the Reduviidae family, triatomines are giant blood-sucking bugs. They are well known in Central and South America where they transmit Trypanosoma cruzi to mammals, including humans, through their feces. This parasitic protozoan is the causative agent of Chagas disease, a major public health issue in endemic areas. Because of the medical and economic impact of Chagas disease, the presence of other arthropod-borne pathogens in triatomines was rarely investigated. Methodology/Principal findings In this study, seven triatomines species involved in the transmission of T. cruzi were molecularly screened for the presence of known pathogens generally associated with arthropods, such as Rickettsia, Bartonella, Anaplasmataceae, Borrelia species and Coxiella burnetii. Of all included triatomine species, only Eratyrus mucronatus specimens tested positive for Bartonella species for 56% of tested samples. A new genotype of Bartonella spp. was detected in 13/23 Eratyrus mucronatus specimens, an important vector of T. cruzi to humans. This bacterium was further characterized by sequencing fragments of the ftsZ, gltA and rpoB genes. Depending on the targeted gene, this agent shares 84% to 91% of identity with B. bacilliformis, the agent of Carrion’s disease, a deadly sandfly-borne infectious disease endemic in South America. It is also closely related to animal pathogens such as B. bovis and B. chomelii. Conclusions As E. mucronatus is an invasive species that occasionally feeds on humans, the presence of potentially pathogenic Bartonella-infected bugs could present another risk for human health, along with the T. cruzi issue. PMID:28095503
Full Text Available Among the Reduviidae family, triatomines are giant blood-sucking bugs. They are well known in Central and South America where they transmit Trypanosoma cruzi to mammals, including humans, through their feces. This parasitic protozoan is the causative agent of Chagas disease, a major public health issue in endemic areas. Because of the medical and economic impact of Chagas disease, the presence of other arthropod-borne pathogens in triatomines was rarely investigated.In this study, seven triatomines species involved in the transmission of T. cruzi were molecularly screened for the presence of known pathogens generally associated with arthropods, such as Rickettsia, Bartonella, Anaplasmataceae, Borrelia species and Coxiella burnetii. Of all included triatomine species, only Eratyrus mucronatus specimens tested positive for Bartonella species for 56% of tested samples. A new genotype of Bartonella spp. was detected in 13/23 Eratyrus mucronatus specimens, an important vector of T. cruzi to humans. This bacterium was further characterized by sequencing fragments of the ftsZ, gltA and rpoB genes. Depending on the targeted gene, this agent shares 84% to 91% of identity with B. bacilliformis, the agent of Carrion's disease, a deadly sandfly-borne infectious disease endemic in South America. It is also closely related to animal pathogens such as B. bovis and B. chomelii.As E. mucronatus is an invasive species that occasionally feeds on humans, the presence of potentially pathogenic Bartonella-infected bugs could present another risk for human health, along with the T. cruzi issue.
Barbosa, Leonardo Rodrigues; Santos, Franciele; Wilcken, Carlos F.; Soliman, Everton P.
It is recorded the occurrence of Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Hemiptera, Thaumastocoridae) in eucalyptus trees in the State of Parana, Brazil. The insect was observed in June at 2009, in Curitiba region.
É registrada a ocorrência de Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Hemiptera, Thaumastocoridae) em árvores de eucalipto no Estado do Paraná. Infestações foram o...
Spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), and brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) are global economic pests. Both pests may co-occur on small fruits, and we investigated whether fruit recently exposed to H. halys woul...
Yanzhuo Zhang; James L. Hanula; Scott Horn; Kristine Braman; Jianghua Sun
The biology of Leptoypha hospita Drake et Poor (Hemiptera: Tingidae), a potential biological control agent from China for Chinese privet, Ligustrum sinense Lour., was studied in quarantine in the United States. Both nymphs and adults feed on Chinese privet mesophyll cells that lead to a bleached appearance of leaves and dieback of branch tips. L. hospita has five...
Full Text Available Description of two new species of Sphenorhina (Hemiptera, Cercopidae, Tomaspidinae from the Neotropical region. Two new species of Sphenorhina Amyot & Serville, S. pseudoboliviana SP. NOV: from Bolivia and S. plata SP. NOV: from Argentina are described and illustrated.
S. V. Joseph; James Hanula; S. K. Braman; F. J. Byrne
Healthy hemlock trees, Tsuga canadensis (L.) Carriere, and hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), populations should favor retention and population growth of adelgid predators such as Laricobius nigrinus Fender (Coleoptera: Derodontidae) and Sasajiscymnus tsugae (Sasaji&McClure) (Coleoptera: Coccinellidae). Eastern hemlock trees...
Aphids in the genus Uroleucon Mordvilko (Hemiptera: Aphididae) are native herbivores that feed on goldenrod (Solidago spp.) and other Asteraceae in North America. The aphids are potential prey for a wide variety of natural enemies, including native and non-native species of lady beetles (Coleoptera...
Lygus hesperus (Hemiptera: Miridae) is an economically important pest affecting cotton crops in California. Lygus feeding causes abscission of cotton squares, with damage severity dependent on size of the square and life stage of the insect. Fifth instar nymphs are the most damaging stage; however, ...
Different concentrations of sucrose were used to investigate how survival and feeding was affected on four species of aphids (Hemiptera: Aphididae). Seven sucrose concentrations were evaluated in feeding chambers fitted with a parafilm membranes and infested with nymphs of Aphis glycines, Diuraphi...
S.V. Joseph; J.L. Hanula; S.K. Braman
We studied the distribution of hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), within hemlock trees for three summer (progrediens) and two winter (sistens) generations in northern Georgia. Eastern hemlock, Tsuga canadensis (L.) Carrie` re, trees were treated with 0, 10, or 25% of 1.5 g of imidacloprid per 2.5 cm of tree diameter at breast height...
Thereza de Almeida Garbelotto
Full Text Available Contributions to the knowledge of Banasa Stål (Hemiptera, Heteroptera, Pentatomidae: Banasa chaca Thomas. The male of Banasa chaca Thomas is described with emphasis on external and internal genitalia and the female internal genitalia is described. Banasa chaca is newly recorded from Buenos Aires Province (Argentina.
During the summer and autumn of 2016, heavy infestations of the mealybug, Phenacoccus solani Ferris (Hemiptera: Pseudococcidae), were observed on pumpkins, Cucurbita spp. (Cucurbitaceae). This was the first record of the species in Egypt. Several populations have been collected in various pumpkin fr...
Aphis elena Lagos-Kutz and Voegtlin, sp. nov. (Hemiptera: Aphididae), is described from specimens collected in Illinois, USA, on the North American native plant, Pycnanthemum virginianum (L.) T. Dur. & B.D. Jacks. ex B.L. Rob. & Fernald (Family: Lamiaceae). Both apterous and alate viviparae are desc...
Kelly L.F. Oten; Allen C. Cohen; Fred P. Hain
The hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), is a pest of eastern and Carolina hemlocks (Tsuga canadensis (L.) Carriere and Tsuga caroliniana Engelmann, respectively) in the eastern United States and has already caused catastrophic changes to eastern forests. As one of the significant...
The Ficus whitefly, Singhiella simplex (Singh) (Hemiptera: Aleyrodidae), is an economic pest of Ficus plant species in India, Burma and China. Severe infestations result in leaf dropping or shedding and defoliation. Since its initial US report in south Florida in 2007, the whitefly has expanded its ...
The ficus whitefly, Singhiella simplex (Singh) (Hemiptera: Aleyrodidae), is a newly-invasive pest of ficus plants in the United States. Very little is known about its biology and life history. Here, we studied development and reproduction at 15, 20, 25, 27, 30 and 35°C. No immatures survived the 35°...
Brown pod-sucking bug, Clavigralla tomentosicollis Stäl (Hemiptera: Coreidae), causes significant damage to cultivated cowpea, Vigna unguiculata Walp, a staple crop in sub-Saharan Africa. C. tomentosicollis pierce and suck sap from cowpea pods, resulting in reduced grain yield and quality. The compl...
Potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Triozidae) is a key pest of potato (Solanum tuberosum L., Solanales: Solanaceae) and a vector of "Candidatus Liberibacter solanacearum," the pathogen associated with zebra chip disease. In addition to its presence on cultivated crops, the p...
Soybean aphid (Aphis glycines Matsumura) (Hemiptera: Aphididae) is a major pest of soybean in northern production regions of North America, and insecticides have been the primary management approach while alternative methods are developed. Knowledge of arthropod natural enemies and their impact on ...
Proper identification of soft scales (Hemiptera:Coccidae) requires preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare soft scale specimens on microscope slides for examination and identification. Steps ranging from collection, speci...
Full Text Available A new soft scale insect, Bombacoccus aguacatae Kondo, gen. n. and sp. n. (Hemiptera: Coccidae collected on the branches and twigs of avocado, Persea americana Mill. (Lauraceae in Colombia, is described and illustrated based on the adult female. An updated taxonomic key to closely related genera of the Toumeyella-group is provided.
Full Text Available Pollinia pollini (Costa (Hemiptera: Asterolecanidae is considered as one of the most important pest infesting olive trees in Egypt. The aim of this work is to study the survey of host plants, geographical distribution and natural enemies as well as the dynamic of P. pollini on olive trees in Egypt. The obtained results indicated that P. pollini infested only olive trees in two Governorates. These are Alexandria and Fayoum Governorates. No parasitoid species were collected and recorded in the present work. Three species of predators were recorded that attacked P. pollini in Egypt. These are the coccinellids, Coccinella undecimpunctata L., Scymnus seriacus Mars. and the Neuroptera species, Chrysoperlla carnae Steph. Also the present study included the dynamics of P. pollini and its predators on olive trees in Alexandria Governorate during 2010 and 2011. Statistical analysis of the effect of weather factors on the population of P. pollini during the 2 years under consideration was discussed. It was concluded that maximum, minimum temperatures and % relative humidity are significant on the population of P. pollini. The trend over both years indicated the occurrence of two generations per year for P. pollini on olive trees in Alexandria.
Rakitov, Roman; Gorb, Stanislav N
Leafhoppers (Insecta, Hemiptera, Cicadellidae) actively coat their integuments with buckyball-shaped submicron proteinaceous secretory particles, called brochosomes. Here, we demonstrate that brochosomal coats, recently shown to be superhydrophobic, act as non-stick coatings and protect leafhoppers from contamination with their own sticky exudates--filtered plant sap. We exposed 137 wings of Alnetoidia alneti (Dahlbom), from half of which brochosomes were removed, to the rain of exudates under a colony of live A. alneti. One hundred and fifty-two droplets became stuck to the bared wings and only three to the intact wings. Inspection of the wings with a scanning electron microscope confirmed that the droplets that had hit the intact wings had rolled or bounced off the brochosomal coats. This is the first experimental study that tested a biological function of the brochosomal coats of leafhopper integuments. We argue that the production of brochosomes in leafhoppers and production of epidermal wax blooms in other sap-sucking hemipterans are alternative solutions, both serving to protect these insects from entrapment by their exudates.
Cruz, Magdalena; Kuesel, Ryan; Gonthier, David J.; Iverson, Aaron; Ennis, Katherine K.; Perfecto, Ivette
The intensification of agriculture drives many ecological and environmental consequences including impacts on crop pest populations and communities. These changes are manifested at multiple scales including small-scale management practices and changes to the composition of land-use types in the surrounding landscape. In this study, we sought to examine the influence of local and landscape-scale agricultural factors on a leafhopper herbivore community in Mexican coffee plantations. We sampled leafhopper (Hemiptera: Cicadellidae) diversity in 38 sites from 9 coffee plantations of the Soconusco region of Chiapas, Mexico. While local management factors such as coffee density, branches per coffee bush, tree species, and density were not important in explaining leafhopper abundance and richness, shade management at the landscape level and elevation significantly affected leafhoppers. Specifically, the percentage of low-shade coffee in the landscape (1,000-m radius surrounding sites) increased total leafhopper abundance. In addition, Shannon’s diversity of leafhoppers was increased with coffee density. Our results show that abundance and diversity of leafhoppers are greater in simplified landscapes, thereby suggesting that these landscapes will have higher pest pressure and may be more at-risk for diseases vectored by these species in an economically important crop. PMID:28355478
Fonseca, M G; Auad, A M; Resende, T T; Hott, M C; Borges, C A V
The aim of this study was to determine the favorable constant temperature range for Mahanarva spectabilis(Distant) (Hemiptera: Cercopidae) development as well as to generate geographic distribution maps of this insect pest for future climate scenarios. M. spectabilis eggs were reared on two host plants (Brachiaria ruziziensis(Germain and Edvard) and Pennisetum purpureum(Schumach)), with individual plants kept at temperatures of 16, 20, 24, 28, and 32 °C. Nymphal stage duration, nymphal survival, adult longevity, and egg production were recorded for each temperature*host plant combination. Using the favorable temperature ranges for M. spectabilis development, it was possible to generate geographic distribution. Nymphal survival was highest at 24.4 °C, with estimates of 44 and 8% on Pennisetum and Brachiaria, respectively. Nymphal stage duration was greater on Brachiaria than on Pennisetum at 20 and 24 °C but equal at 28 °C. Egg production was higher on Pennisetum at 24 and 28 °C than at 20 °C, and adult longevity on Pennisetum was higher at 28 °C than at 20 °C, whereas adult longevity at 24 °C did not differ from that at 20 and 28 °C. With these results, it was possible to predict a reduction in M. spectabilis densities in most regions of Brazil in future climate scenarios. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.
Serguei V. TRIAPITSYN
Full Text Available Se revisaron los parasitoides oófagos (Hymenoptera: Eulophidae, Mymaridae, y Platygastridae de Megamelus spp. (Hemiptera: Delphacidae de la Argentina, y se presenta una clave para su identificación. Se describen cuatro especies nuevas: Anagrus (Anagrus empanadus Triapitsyn, sp. nov. (Mymaridae, parasitoide de M. scutellaris Berg que se alimenta de camalote, Eichhornia crassipes (Martius Solms-Laubach; Aprostocetus (Ootetrastichus riverplaticus Triapitsyn, sp. nov. (Eulophidae: Tetrastichinae, parasitoide de M. bellicus Marino de Remes Lenicov & Sosa; A. (Ootetrastichus yerbamatei Triapitsyn, sp. nov. (parasitoide de M. bellicus, M. scutellaris y Megamelus sp., todos de la provincia de Buenos Aires (A. (Ootetrastichus yerbamatei también se encuentra en Formosa; y Parascelio sabcli Triapitsyn, sp. nov. (Platygastridae: Scelioninae, parasitoide de M. scutellaris en Formosa, la asociación con el huésped es tentativa. Se incluyen otros parasitoides oófagos conocidos de Megamelus spp. en la Argentina, tales como Kalopolynema (Kalopolynema poema Triapitsyn & Berezovskiy (Mymaridae, parasitoide de M. scutellaris en Buenos Aires y también Cremastobaeus atratus Loiácono & Mulvani (Platygastridae: Scelioninae, parasitoide de M. scutellaris en Formosa, la asociación con el huésped es tentativa.
Vennila, S; Prasad, Y G; Prabhakar, M; Agarwal, Meenu; Sreedevi, G; Bambawale, O M
The exotic cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) invaded India during 2006, and caused widespread infestation across all nine cotton growing states. P. solenopsis also infested weeds that aided its faster spread and increased severity across cotton fields. Two year survey carried out to document host plants of P. solenopsis between 2008 and 2010 revealed 27, 83, 59 and 108 weeds belonging to 8, 18, 10 and 32 families serving as alternate hosts at North, Central, South and All India cotton growing zones, respectively. Plant species of four families viz., Asteraceae, Amaranthaceae, Malvaceae and Lamiaceae constituted almost 50% of the weed hosts. While 39 weed species supported P. solenopsis multiplication during the cotton season, 37 were hosts during off season. Higher number of weeds as off season hosts (17) outnumbering cotton season (13) at Central over other zones indicated the strong carryover of the pest aided by weeds between two cotton seasons. Six, two and seven weed hosts had the extreme severity of Grade 4 during cotton, off and cotton + off seasons, respectively. Higher number of weed hosts of P. solenopsis were located at roadside: South (12) > Central (8) > North (3) zones. Commonality of weed hosts was higher between C+S zones, while no weed host was common between N+S zones. Paper furnishes the wide range of weed hosts of P. solenopsis, discusses their significance, and formulated general and specific cultural management strategies for nationwide implementation to prevent its outbreaks.
Ultrastructure and morphometry of eggs of Triatoma rubrovaria (Blanchard, 1843), Triatoma carcavalloi Juberg, Rocha & Lent, 1998 and Triatoma circummaculata (Stål, 1859) (Hemiptera-Reduviidae-Triatominae).
Cardozo-de-Almeida, Margareth; Castro-de-Souza, Simone; De Oliveira, Maria Luiza Ribeiro; De Almeida, Sérgio Antônio Silva; Gonçalves, Teresa Cristina Monte; Dos Santos-Mallet, Jacenir Reis
This study analyzed the body and the operculum of eggs of Triatoma rubrovaria, T. carcavalloi and T. circummaculata, considered sylvatic species that live in sympatry.Triatoma rubrovaria is currently considered the most important vector of Trypanosoma cruzi in the rural areas of the state of Rio Grande do Sul, followed by T.circummaculata. Significant differences other than morphometry have been observed in the egg structures of the three species using traditional microscopy and scanning electron microscopy. Triatoma circummaculata eggs are smaller than those of T.rubrovaria and T. carcavalloi. The average number of perforations in corionic cells in the egg body is higher for the T. rubrovaria. The average number of perforations in the operculum cell is higher in T. circummaculata. This is the first morpho-structural description of T. carcavalloi eggs. These results widen the concept of these three species and create new subsidies for the entomological monitoring in areas in which these vectors may infest human living quarters.
Comparative study of the stridulatorium sulcus, buccula and rostrum of nymphs of Triatoma klugi Carcavallo et al, Triatoma vandae Carcavallo et al and Triatoma williami Galvão et al (Hemiptera: Reduviidae)
Silva, Maria B A; Jurberg, José; Galvão, Cleber; Barbosa, Helene S
Ultrastructural analysis of the ventral region of the head - rostrum, buccula and stridulatorium sulcus - of 1st, 3rd and 5th instars of Triatoma klugi Carcavallo et al, Triatoma vandae Carcavallo et al, and Triatoma williami Galvão et al, are described in here. Morphological differences in the analyzed structures for all three Triatoma species studied were detected under scanning electron microscopy, allowing their grouping by their morphological similarities. Species-specific differences at...
Abstract. Rhodnius stali Lent, Jurberg & Galvão is a Chagas Disease vector that colonize houses in the Alto Beni region, Bolivia and its biology is poorly known. Aiming to enhance the understanding about their biology, we observed a few parameters of its life cycle, at nymphal stages, comparing them with Rhodnius pictipes Stål a morphologically similar and phylogenetically close species. The following parameters were observed: time of hatching, development time from egg to adult (male and female separately, mortality rate, age at first blood meal and blood volume ingested by nymphs. In general, it was observed that the R. stali has longer cycle than R. pictipes, and in both species, the time between hatching the egg to adult in females is lower. Interestingly for R. stali, which is known to be capable of colonizing households, the mortality rate of nymphs was higher than observed in R. pictipes, something unexpected for species that colonize artificial structures and was observed in artificial environment. For R. stali, the first blood meal was, on average, four days later than for R. pictipes, species that ingested a greater total blood volume, possibly because of its bigger size. By knowing in depth the biological aspects of these species it will be possible to direct vector control more accurately, especially in regions where they colonize houses, as in the Alto Beni, Bolivia.
Resultados. Los promedios de duración de todos los estadios de desarrollo de R. colombiensis fueron mayores que en R. prolixus, presentando diferencias significativas en el tiempo transcurrido desde huevo hasta adulto. Los promedios de huevos puestos y huevos fértiles, presentaron diferencias significativas, siendo mayores en R. prolixus que en R. colombiensis. El porcentaje total de mortalidad de R. colombiensis fue de 31,5% y de 6,5% para R. prolixus. La longevidad en las hembras fue mayor en R. prolixus. Conclusiones. Los estadios de R. prolixus tienen menor duración, las ninfas en general realizan menor número de comidas que R. colombiensis, los adultos de R. prolixus toman mayor número de comidas y ovipositan mayor número de huevos fértiles, presentando hembras con mayor longevidad. Todos estos parámetros indican que R. prolixus presenta mejor éxito reproductivo que R. colombiensis, en las condiciones experimentales utilizadas. Los datos inéditos sobre el ciclo de vida de R. colombiensis serán de utilidad para el mantenimiento de las colonias en el laboratorio.
Conclusión. En ninfas de primer estadio de T. dimidiata y T. maculata los insecticidas piretroides fueron mas efectivos; en ninfas de quinto estadio de T. dimidiata la efectividad de los piretroides del organofosforado fue diferente con las DL50; las ninfas de este estadio requirieron dosis altas comparadas con las utilizadas para otros triatominos, lo cual sugiere una baja susceptibilidad. La DL99 para el organofosforado fue significativamente menor, lo que podría indicar una mayor efectividad en campo. Es importante realizar estudios de efectos sinergistas para mostrar el posible rol de mecanismos bioquímicos que determine su tolerancia a los piretroides, esto representa un nuevo reto para las campañas de control en los países andinos y centroamericanos donde esta especie es endémica.
Marcos Takashi Obara
Full Text Available INTRODUÇÃO: Populações de Triatoma sordida Stål, 1859 foram investigadas quanto à suscetibilidade à deltametrina. MÉTODOS: Análise por meio de bioensaios por aplicação tópica em 11 populações de T. sordida procedentes dos Estados de Goiás, Mato Grosso e Mato Grosso do Sul. RESULTADOS: As estimativas de DL50 e RR50 demonstraram elevados níveis de suscetibilidade (DL50 < 1 e RR50 < 2. Entretanto, as análises do coeficiente angular da curva dose resposta revelaram que as populações de triatomíneos dos municípios de Firminópolis/GO, Posse/GO, Poxoréu/MT, Douradina/MS e Aparecida do Taboado/MS apresentam maiores probabilidades de evolução de resistência, portanto, mais propícias a tolerar o tratamento com deltametrina. CONCLUSÕES: Detectaram-se pequenas alterações de suscetibilidade e baixos níveis de resistência, porém as alterações temporais de suscetibilidade deverão ser continuamente monitoradas, a fim de nortear adequadamente as ações de controle dos vetores da DC.
Validation of reference genes for expression analysis in the salivary gland and the intestine of Rhodnius prolixus (Hemiptera, Reduviidae under different experimental conditions by quantitative real-time PCR
Paim Rafaela M
Full Text Available Abstract Background Rhodnius prolixus is a blood-feeding insect that can transmit Trypanosoma cruzi and Trypanosoma rangeli to vertebrate hosts. Recently, genomic resources for invertebrate vectors of human pathogens have increased significantly, and R. prolixus has been one of the main species studied among the triatomines. However, the paucity of information on many of the fundamental molecular aspects of this species limits the use of the available genomic information. The present study aimed to facilitate gene expression studies by identifying the most suitable reference genes for the normalization of mRNA expression data from qPCR. Results The expression stability of five candidate reference genes (18S rRNA, GAPDH, β-actin, α-tubulin and ribosomal protein L26 was evaluated by qPCR in two tissues (salivary gland and intestine and under different physiological conditions: before and after blood feeding and after infection with T. cruzi or T. rangeli. The results were analyzed with three software programs: geNorm, NormFinder and BestKeeper. All of the evaluated candidate genes proved to be acceptable as reference genes, but some were found to be more appropriate depending on the experimental conditions. 18S, GAPDH and α-tubulin showed acceptable stability for studies in all of the tissues and experimental conditions evaluated. β-actin, one of the most widely used reference genes, was confirmed to be one of the most suitable reference genes in studies with salivary glands, but it had the lowest expression stability in the intestine after insect blood feeding. L26 was identified as the poorest reference gene in the studies performed. Conclusions The expression stability of the genes varies in different tissue samples and under different experimental conditions. The results provided by three statistical packages emphasize the suitability of all five of the tested reference genes in both the crop and the salivary glands with a few exceptions. The results emphasise the importance of validating reference genes for qRT-PCR analysis in R. prolixus studies.
A new species and karyotype variation in the bordering distribution of Mepraia spinolai (Porter) and Mepraia gajardoi Frías et al (Hemiptera: Reduviidae: Triatominae) in Chile and its parapatric model of speciation.
In the present study, the morphology, color pattern, chromosomal complement and aspects of meiosis in natural populations at the borders of the distributions of Mepraia gajardoi Frías et al and Mepraia spinolai (Porter) are described. The males of these bordering populations are brachypterous or macropterous, while females are always micropterous. Morphological and cytogenetic data indicated that the populations that border the distributions of M. gajardoi and M. spinolai, belong to a different species of parapatric origin.
Teresa Cristina Monte Goncalves
Full Text Available Utilizando a microscopia ótica (MO e eletrônica de varredura (MEV procurou-se fornecer dados a taxionomia através da estrutura dos ovos e morfologia das ninfas, destes vetores da doença de Chagas. Os ovos em MO apresentam a superfície exocorial do opérculo e do corpo dividida em áreas poligonais com ornamentação própria; em T. maculata o exocório do corpo tem áreas indefinidas. Em MEV o exocório dos opérculos apresenta áreas poligonais de superfície estofada com pequena sulcos irregulares e perfurações distribuídas aleatoriamente nas duas espécies. O exocório do corpo apresenta: em T. maculata áreas acolchoadas com perfurações mais numerosas nos bordos, visualizando-se a borda corial, goteira espermática, aerópilas e micrópilas; em T. pseudomaculata as áreas são planas com numerosas perfurações. Nas ninfas o sulco estridulatório e o rostro apresentam diferenças significativas. O sulco estridulatórios em MO possibilitou diferenciar ninfas de 1º, 2º e 3º estádios, os 4º e 5º estádios apresentam-se semelhantes. Em MEV a diferenciação é acentuada. O rostro em MO apresenta pilosidade característica a partir do 3º estádio. T. maculata apresenta pêlos curtos e esparsos no 1º e 2º artículos e longos e numerosos no 3º, em T. pseudo-maculata semelhantes, porém mais curtos no 3º artículo.As an aid in the identification of vectors of Chagas' disease we have studied the structure of the eggs and morphology of nymphs by optical microscopy (OM and scanning electron microscopy (SEM. The eggs as seen by OM show the exochorion of the body doesn't have defined areas. In SEM the exochorion of the cap appears as upholstered polygonal areas with small irregular grooves and perforations spread at random in both species. The exochorion of the body in T. maculata is upholstered with more numerous perforations on the edge visualizing the rim of the shell, spermatic groove, pseudomicropyles and micropyles; in T. pseudomaculata there are flat areas with numerous perforations. The nymphs show differences cencerning the stridulatory groove and rostrum. The stridulatory groove when seen by OM shows differences in nymphs of 1st, 2nd and 3rd intars, while 4th and 5th are similar; in SEM the differences are clear. In OM the rostrum shows typical pilosity to each species from 3rd instar. In T. maculata the setae are short and scattered on the 1st and 2nd segments and are long and numerous on the 3rd. In T. pseudomaculata the setae are similar but are short on the 3rd segment.
Leyria, Jimena; Fruttero, Leonardo L.; Nazar, Magalí; Canavoso, Lilián E.
In this work, we have investigated the involvement of DmCatD, a cathepsin D-like peptidase, and acid phosphatase in the process of follicular atresia of Dipetalogaster maxima, a hematophagous insect vector of Chagas’ disease. For the studies, fat bodies, ovaries and hemolymph were sampled from anautogenous females at representative days of the reproductive cycle: pre-vitellogenesis, vitellogenesis as well as early and late atresia. Real time PCR (qPCR) and western blot assays showed that DmCatD was expressed in fat bodies and ovaries at all reproductive stages, being the expression of its active form significantly higher at the atretic stages. In hemolymph samples, only the immunoreactive band compatible with pro-DmCatD was observed by western blot. Acid phosphatase activity in ovarian tissues significantly increased during follicular atresia in comparison to pre-vitellogenesis and vitellogenesis. A further enzyme characterization with inhibitors showed that the high levels of acid phosphatase activity in atretic ovaries corresponded mainly to a tyrosine phosphatase. Immunofluorescence assays demonstrated that DmCatD and tyrosine phosphatase were associated with yolk bodies in vitellogenic follicles, while in atretic stages they displayed a different cellular distribution. DmCatD and tyrosine phosphatase partially co-localized with vitellin. Moreover, their interaction was supported by FRET analysis. In vitro assays using homogenates of atretic ovaries as the enzyme source and enzyme inhibitors demonstrated that DmCatD, together with a tyrosine phosphatase, were necessary to promote the degradation of vitellin. Taken together, the results strongly suggested that both acid hydrolases play a central role in early vitellin proteolysis during the process of follicular atresia. PMID:26091289
Conclusión. R. colombiensis presenta menor número de defecaciones que R. prolixus durante la comida. Un mayor porcentaje de R. prolixus defecan durante los 10, 60 y 95 min después de la alimentación. Sin embargo, R. colombiensis permanece mayor tiempo asociado al hospedero vertebrado, lo cual aumentaría la probabilidad de transmisión teniendo en cuenta el ingreso ocasional de los adultos a las viviendas humanas y sus elevadas prevalencias con T. cruzi y T. rangeli.
Santos, Helen Pinto; Rost-Roszkowska, Magdalena; Vilimova, Jitka; Serrão, José Eduardo
Heteroptera have diverse feeding habits with phytophagous, zoophagous, and haematophagous species. This dietary diversity associated with the monophyly of Heteroptera makes these insects a good object for comparative studies of the digestive tract. This work compares the ultrastructure of the middle midgut region in the phytophagous Coptosoma scutellatum (Plataspidae), Graphosoma lineatum (Pentatomidae), Kleidocerys resedae (Lygaeidae), and zoophagous Rhynocoris iracundus (Reduviidae), Nabis rugosus (Nabidae), and Himacerus apterus (Nabidae), to verify if diet affects midgut cells in phylogenetically related insects. The middle region of the midgut was used for comparison because it is the main site for digestion and absorption of the midgut. The digestive cell ultrastructure was similar in the six species, with features of secretory, absorptive, transport, storage, and excretory cells, suggesting a stronger correlation of middle digestive cell ultrastructure with the phylogeny of these species than with the different heteropteran feeding habits.
Castro-Huertas, Valentina; Schwertner, Cristiano F; Fernández, Fernando
New records of genera and species of stink bugs (Hemiptera: Pentatomidae) from Colombia are provided. Two genera are new records for South America: Alathetus and Schraderiellus. Fifteen genera are new record for Colombia: Agaclitus, Boea, Ceratozygum, Euthyrhynchus, Eritrachys, Doesburguedessa, Lopadusa, Marmessulus, Paralincus, Patanius, Peromatus, Phalaecus, Phoeacia, Rio, and Tyrannocoris. Forty-nine species from five subfamiles are recorded for the first time in Colombia. Asopinae: Coryzorhaphis carneolus Erichson, Coryzorhaphis superba Breddin, Euthyrhynchus floridanus (Linnaeus), Podisus sagitta Fabricius, Stiretrus anchorago (Fabricius), Stiretrus cinctellus Germar, Tylospilus peruvianus Horvath, Tyrannocoris nigriceps Thomas. Cyrtocorinae: Ceratozygum horridum (Germar). Discocephalinae: Agaclitus dromedarius Stål, Antiteuchus melanoleucus (Westwood), Antiteuchus sepulcralis (Fabricius), Dinocoris gibbosus (Fallou), Dinocoris variolosus (Linnaeus), Discocephalessa terminalis (Walker), Dryptocephala crenata Ruckes, Dryptocephala dentifrons (Latreille), Eurystethus ovalis Ruckes, Paralcippus dimidiatus (Ruckes), Alathetus rufitarsus Dallas, Eritrachys bituberculata Ruckes, Paralincus bimaculatus (Ruckes), Schraderiellus cinctus (Ruckes), Xynocoris recavus (Garbelotto & Campos). Edessinae: Brachystethus cribus (Fabricius), Brachystethus tricolor Bolívar, Doesburguedessa elongatispina Fernandes and Lopadusa fuscopunctata (Distant). Pentatominae: Banasa fulgida Thomas, Banasa paraexpallescens Thomas, Dichelops divisus (Walker), Dichelops nigrum Bergroth, Euschistus carbonerus Rolston, Mormidea bovilla (Distant), Mormidea triangularis (Walker), Murgantia bifasciata Herrich-Schaeffer, Murgantia violascens (Westwood), Oebalus pugnax (Fabricius), Oebalus ypsilon-griseus (DeGeer), Odmalea concolor (Walker), Patanius vittatus Rolston, Proxys albopunctulatus (Palisot), Proxys punctulatus (Palisot), Rhyncholepta grandicallosa Bergroth, Rio insularis Ruckes, Roferta
Montemayor, Sara Itzel; Dellapé, Pablo Matías
We present a list of the type material of Heteroptera deposited in the entomological collection of the Museo de La Plata (Buenos Aires, Argentina) in the last six years and or, not included in previous catalogs. This catalog includes 244 specimens belonging to 43 holotypes, one neotype, and 200 paratypes. The type material examined belongs to 50 species from 43 genera distributed in 16 families: Schizopteridae, Hydrometridae, Naucoridae, Thaumastocoridae, Miridae, Tingidae, Vianaididae, Reduviidae, Alydidae, Rhopalidae, Largidae , Berytidae, Blissidae, Lygaeidae, Oxycarenidae, and Rhyparochromidae.
Díaz, Sebastián; Villavicencio, Bianca; Correia, Nathália; Costa, Jane; Haag, Karen L
Triatomine bugs (Hemiptera: Reduviidae) are vectors of the flagellate Trypanosoma cruzi, the causative agent of Chagas disease. The study of triatomine gut microbiota has gained relevance in the last years due to its possible role in vector competence and prospective use in control strategies. The objective of this study is to examine changes in the gut microbiota composition of triatomines in response to a T. cruzi-infected blood meal and identifying key factors determining those changes. We sampled colony-reared individuals from six triatomine vectors (Panstrongylus megistus, Rhodnius prolixus, Triatoma brasiliensis, T. infestans, T. juazeirensis and T. sherlocki) comparing experimentally T. cruzi strain 0354-challenged and non-challenged insects. The microbiota of gut and gonad tissues was characterized using high throughput sequencing of region V3-V4 of bacterial 16S rRNA gene. The triatomine microbiota had a low intra-individual diversity, and a high inter-individual variation within the same host species. Arsenophonous appeared as the dominant triatomine bacterial symbiont in our study (59% of the total 16S coverage), but there were significant differences in the distribution of bacterial genera among vectors. In Rhodnius prolixus the dominant symbiont was Pectobacterium. Trypanosoma cruzi-challenge significantly affects microbiota composition, with challenged vectors harbouring a significantly more diverse bacterial community, both in the gut and the gonads. Our results show that blood-feeding with T. cruzi epimastigotes strongly affects microbiota composition in a species-specific manner. We suggest that triatomine-adapted enterobacteria such as Arsenophonus could be used as stable vectors for genetic transformation of triatomine bugs and control of Chagas disease.
María L. GASPARINI
Full Text Available Se informa acerca del hallazgo de Clitostethus arcuatus (Rossi (Coleptera: Coccinellidae, Scymninae en plantas de olivo infestados con Siphoninus phillyreae (Haliday (Hemiptera: Aleyrodidae. El material se recolectó en plantaciones de olivo de los departamentos Junín, San Martín, Rivadavia y Maipú (Mendoza, Argentina durante los monitoreos de identificación de enemigos naturales de la «mosca blanca del fresno», Siphoninus phillyreae.
Abstract. Leptoglossus zonatus (Dallas (Hemiptera: Coreidae is a phytophagous bug that can be found in several crops due to availability of food and favorable conditions for the development. The aim of this research was to record the occurrence of L. zonatus colonizing plants of Malpighia emarginata Sessé & Moc (Malpighiaceae, Morus nigra Linnaeus (Moraceae, Mangifera indica Linnaeus (Anacardiaceae in Municipality of Sinop, Mato Grosso, Brazil. L. zonatus should be included in monitoring for the Integrated Pest Management (IPM in these plants.
Watanabe, Kisaki; Shimizu, Nobuhiro
Although the nymphs of Corythucha marmorata form clusters on the undersides of host plant leaves, as frequently observed for Hemiptera, the adults are scattered in the vicinity of the nymph population. By investigating the biological activities of volatile secretions from the adult, we found that the secretions activated male mounting behaviour. A chemical analysis revealed that borneol was a common component of the secretions from both sexes. The absolute configuration of the natural product...
Souza, Efrain de Santana [UNESP; Lopes Baldin, Edson Luiz [UNESP; Goncalves Franco da Silva, Jose Paulo [UNESP; Lourencao, Andre Luiz
Nezara viridula (L.) (Hemiptera: Pentatomidae) is a cosmopolitan insect that causes economic damages to several cultures, in particular soybeans (Glycine max [L.] Merr.) Among the techniques that involve Integrated Pest Management, the resistance of plants is pointed as a tool of great value and can contribute to the reduction of populations of insects. The feeding preferences of adults of southern green stink bug (N. viridula), and the attractiveness of soybean genotypes were evaluated under...
Lashkari, Mohammadreza; Hentz, Matthew G.; Boykin, Laura M.
The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vector of citrus greening disease pathogen, Huanglongbing (HLB), is considered the most serious pest of citrus in the world. Prior molecular based studies have hypothesized a link between the D. citri in Iran and the USA (Florida). The purpose of this study was to collect morphometric data from D. citri populations from Iran (mtCOI haplotype-1), Florida (mtCOI haplotype-1), and Pakistan (mtCOI haplotype-6), to de...
Zarin, Mahtab; Zubeda; Seth, R.K.; Seth, Ranjana
Ionizing radiation can be considered as a possible alternative for treating agricultural products to overcome quarantine barriers against the Solenopsis mealy bug, Phenacoccus solenopsis (Hemiptera: Pseudococcidae). Exposure of ionizing radiation is one of the quarantine treatments which penetrate commodities quickly and most commodities can tolerate irradiation at doses that kill the pest. Evaluation of various bio-characteristics (survival, metamorphosis and reproductive potential) of Phenacoccus solenopsis irradiated in various life stages was attempted to ascertain the lethal doses and sublethal doses having sterilizing potential. A dose of 40Gy administered to the first instar nymph (N 1 ) inhibited formation of adult male, whereas 100Gy checked the transformation of N 1 up to adult female. Males exhibited short life span and appeared to have no or limited role in progeny formation. Males were more radio-sensitive than the female mealy bugs. Further, in case of N 2 treatment, a dose of 100Gy completely inhibited adult male formation, and 150 Gy could completely inhibit male adult formation. The sexes were discernible only after N 2 . A dose of 500Gy given to female-N 3 totally inhibited adult formation. The developmental period of female N 3 was protracted with increase in radiation dosage. The efficacy of radiation at dose range, 5-300Gy, was evaluated on N 3 and N 4 male nymphs. Irradiation affected metamorphosis and reduced adult formation. For instance, a dose of 300Gy caused 0% male adult development from N 4 . 400Gy was almost sterilizing dose for 11-12 day old female mealy bug, and this sterilizing dose reduced oviposition by 28.1%; whereas 200Gy was found to induce sterility in 5-6 day old female mealy bug, with about 50% reduction in oviposition. The freshly emerged female adults (0-1 day old) was the most sensitive stage than the adult mealy bugs in their older phase, and it was completely sterilized by 40Gy. The data suggests a definite role of
Jesse L. Albertson
Full Text Available The treehopper genus Tolania Stål (Hemiptera: Membracidae: Nicomiinae: Nicomiini and 69 valid species (59 new are described and illustrated based on adult morphology. Ten informal species groups are recognized based on a previously published phylogenetic analysis: (1 the dira species group comprising T. calista sp. nov., T. dira sp. nov., T. inca sp. nov., T. macaria sp. nov., T. secoya sp. nov., and T. zaparo sp. nov.; (2 the fasciata species group comprising T. fasciata (Walker, T. gracilis sp. nov., and T. laticlava sp. nov.; (3 the femoralis species group comprising T. femoralis Stål, T. fraterna Stål, and T. roberti sp. nov.; (4 the furcata species group comprising T. furcata sp. nov., T. tryphena sp. nov., and T. venezuelensis sp. nov.; (5 the hispida species group comprising T. alida sp. nov., T. hispida sp. nov., and T. periculosa sp. nov.; (6 the malefica species group comprising T. cactina sp. nov., T. curvata sp. nov., T. grallator sp. nov., T. jocosa sp. nov., T. mackameyi sp. nov., T. malefica sp. nov., T. obliqua (Walker, and T. terencia sp. nov.; (7 the obtusa species group comprising T. obtusa Fowler, T. obunca sp. nov., and T. torosa sp. nov.; (8 the opponens species group comprising T. alvira sp. nov., T. arcuata sp. nov., T. damia sp. nov., T. insolita sp. nov., T. lunata sp. nov., T. lurida sp. nov., T. opponens (Walker, T. oriana sp. nov., T. reflexa sp. nov., T. risa sp. nov., T. sinuata sp. nov., T. trilobata sp. nov., T. tumida sp. nov., T. umbella sp. nov., T. vitocensis sp. nov., T. woodi sp. nov., and T. xantha sp. nov.; (9 the peltacauda species group comprising T. brasiliensis sp. nov., T. iratafelis sp. nov., T. modesta sp. nov., T. peltacauda sp. nov., T. picta sp. nov., and T. thyrea sp. nov.; and (10 the semipellucida species group comprising T. atrata sp. nov., T. fimbriata sp. nov., T. nicia sp. nov., and T. semipellucida Stål. The following new species are not placed in species groups: T. anomala sp. nov
Oku, K.; Yamane, T.
In insects, male-derived substances transferred during copulation often alter female physiology. Thus these substances may affect female behaviour, including mating receptivity and release of sex pheromone. In the sorghum plant bug Stenotus rubrovittatus (Matsumura) (Hemiptera: Miridae), males
Potential use of the fungus Beauveria bassiana against the western flower thrips Frankliniella occidentalis without reducing the effectiveness of its natural predator Orius sauteri (Hemiptera: Anthocoridae)
Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important predator of western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Orius sauteri would be directly exposed to the entomopathogenic fungus Beauveria bassiana (Bals.) Vuillemin in the field should the fu...
Kondo, Takumasa; Cortés, Ronald Simbaqueba
The crape myrtle aphid Sarucallis kahawaluokalani (Kirkaldy) (Hemiptera: Aphididae) collected on Lagerstroemia indica (Lythraceae) is herein reported as a new invasive species in the city of Palmira, State of Valle del Cauca, and on San Andres island, in the State of San Andres, Old Providence and Santa Catalina, Colombia. The species is illustrated and diagnosed. A brief review of recent invasive species in Colombia, i.e., Ceroplastes rubens Maskell (Hemiptera: Coccidae), Crypticerya multici...
The brown stink bug (BSB), Euschistus servus (Say) (Hemiptera: Pentatomidae), is a serious economic pest of corn production in the Southeastern U. S. The BSB population dynamics was monitored for 17 wks from tasseling to pre-harvest of corn plants (i.e., late May to mid-September) using pheromone ...
Full Text Available Tamarixia aguacatensis Yefremova, sp. n. (Hymenoptera: Eulophidae: Tetrastichinae is described from Mexico as a parasitoid of the avocado psyllid, Trioza aguacate Hollis & Martin (Hemiptera: Triozidae. Trioza aguacate is a serious pest of avocado, Persea americana Miller. A key to the species of Tamarixia Mercet in Mexico is given.
Exposure of a pyrethroid-susceptible strain of bed bugs, Cimex lectularius L. (Hemiptera: Cimicidae) to varying concentrations of deltamethrin for 24h indicated there was no significant difference in mortality between males, females, and nymphs at 24h or 168h post-exposure. Most bed bugs classified ...
S.V. Joseph; James Hanula
Understanding how fertilization affects host resistance to hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera:Adelgidae), is important because fertilizers are often used to grow resistant selections to a suitable size for testing. We evaluated four hemlock species (Tsuga) under three different fertilizer regimes to assess whether fertility affected resistance to...
Lygus hesperus Knight (Hemiptera: Miridae) is a key agricultural pest in the western United States. In a recent study, proteins from Pantoea ananatis and Serratia marcescens (Enterobacteriales: Enterobacteriaceae) were identified in diet that was stylet-probed and fed upon by L. hesperus adults. P...
The banana spotting bug Amblypelta lutescens lutescens Distant (Hemiptera: Coreidae) is one of the principal pests of tree fruits and nuts across northern and eastern Australia. Apart from damage assessments in orchards, there are currently no other methods for monitoring bug activity to aid manage...
Full Text Available Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae is reported on Brassica oleracea var. capitata (Brassicaceae in northwestern Iran. Tamarixia monesus (Walker (Hymenoptera: Chalcidoidea, Eulophidae was reared for the first time on B. tremblayi, and compared with Tamarixia tremblayi, another parasitoid of B. tremblayi. This is a new record of T. monesus from the Middle East.
Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a major pest of several important crops including vegetables, cereals, fruits, and ornamentals grown worldwide. One important mode of its dispersal is through the trans-boundary movement of infested plant materials. In order to prevent the sprea...
Velema, H.P.; Hemerik, L.; Hoddle, M.S.; Luck, R.F.
1. Many cicadellid females in the tribe Proconiini (Hemiptera: Cicadellidae) cover their egg masses with specialised, usually rod-shaped, brochosomes as the eggs are being laid. The brochosomes are produced in Golgi complexes in the Malpighian tubules of Cicadellidae. In contrast to the gravid
Vandervoet, Timothy F; Ellsworth, Peter C; Carrière, Yves; Naranjo, Steven E
Conservation biological control can be an effective tactic for minimizing insect-induced damage to agricultural production. In the Arizona cotton system, a suite of generalist arthropod predators provides critical regulation of Bemisia tabaci Gennadius (MEAM1) (Hemiptera: Aleyrodidae) and other pests. Arthropod predator and B. tabaci populations were manipulated with a range of broad-spectrum and selective insecticide exclusions to vary predator to prey interactions in a 2-yr field study. Predator to prey ratios associated with B. tabaci densities near the existing action threshold were estimated for six predator species found to be negatively associated with either adult and/or large nymphs of B. tabaci [Misumenops celer (Hentz) (Araneae: Thomisidae), Drapetis nr divergens (Diptera: Empididae), Geocoris pallens Stäl (Hemiptera: Geocoridae), Orius tristicolor (White) (Hemiptera: Anthocoridae), Chrysoperla carnea s.l. (Neuroptera: Chrysopidae), and Collops spp. (Coleoptera: Melyridae)] with the first three most consistently associated with declining B. tabaci densities. Ratios ranged from 1 M. celer per 100 sweeps to 1 B. tabaci adult per leaf to 44 D. nr. divergens per 100 sweeps to 1 large nymph per leaf disk. These ratios represent biological control informed thresholds that might serve as simple-to-use decision tool for reducing risk in the current B. tabaci integrated pest management strategy. The identification of key predators within the large, flexible food web of the cotton agro-ecosystem and estimation of predator to B. tabaci ratios clarifies the role of key predators in B. tabaci suppression, yielding potential decision-making advantages that could contribute to further improving economic and environmental sustainability of insect management in the cotton system.
Virla, Eduardo G; Logarzo, Guillermo A; Paradell, Susana L
The paleartic tamarix leafhopper, Opsius stactogalus Fieber (Hemiptera: Cicadellidae), can reduce the growth of tamarisk due to the aggregate feeding imposed by their populations. The species was mentioned for Argentina in Metcalf's catalogue (1967) without locality or region reference, and the contributions on Cicadellidae published by many authors after Metcalf omitted this distributional data. Populations of O. stactogalus on Tamarix sp. were found in 12 sites between 28 degrees 48' to 39 degrees 17' S and 64 degrees 06' to 70 degrees 04' W, located in both the Neotropical and Andean biogeographic regions.
Cornejo, J.F.; Chica, E.J.
Abstract Adults and nymphs of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), were collected in the Guayaquil, Samborondón, and Durán cantons in coastal Ecuador. Psyllids were found in high numbers in citrus ( Citrus spp., Sapindales: Rutaceae) and orange jasmine ( Murraya exotica [L.] Jack, Sapindales: Rutaceae) trees within the Guayaquil-Samborondon-Duran conurbation; however, none was found during scoutings in the main citrus producing areas in coastal Ecuador. To the best of our knowledge, this is the first report of D. citri in Ecuador and the Pacific coastal plain of South America. PMID:25527601
Full Text Available Idiopterus nephrelepidis (Hemiptera: Aphididae is reported for the first time in Bulgaria on ornamental ferns in four greenhouses in Sofia and Varna. Dense colonies of apterous viviparous females and larvae were observed. The established host plants are Nephrolepis exaltata, Asplenium nidus and Pteris cretica. Infested ferns exhibit leaf deformation. The aphids were reared in laboratory conditions for four months. A morphometric study of apterae was carried out. Taking into account the presence of host plants of I. nephrelepidis in Bulgaria which are native to the local flora and the reports of the aphid from the Balkan area, it may spread in the country outdoors.
Cossolin, Jamile Fernanda Silva
Nos insetos, os espermatozoides exibem morfologias muito variáveis, porém apresentam alguns caracteres constantes para a espécie e, em geral, somente o tipo responsável pela fertilização é produzido. Entretanto, tem sido observado em vários grupos, espécies que produzem mais de um tipo de espermatozoide, sendo mais comum a ocorrência de dois tipos (dimorfismo). Todavia, em Hemiptera são observadas espécies que produzem três ou mais tipos (polimorfismo). Neste sentido, este trabalho teve como ...
Alexandre Hiroshi Utiyama
Este trabalho aborda um estudo detalhado sobre o sistema digestivo da cigarrinha sugadora de xilema, Bucephalogonia xanthophis (Hemiptera: Cicadellidae), num enfoque morfofuncional. Sob o ponto de vista anatômico, o sistema digestivo é constituído, como na maioria dos insetos, por três regiões: o intestino anterior, o intestino médio e o intestino posterior. O intestino anterior é formado por um tubo simples, o esôfago, sem qualquer diferenciação anatômica. O intestino médio tem início na câm...
De Remes Lenicov, Ana M Marino; Maciá, Arnaldo; Pianzola, Bruno
A catalog of the 161 type specimens of species of Hemiptera Cicadidae housed in the collection of the Entomology Division of the Museo de La Plata is presented. This collection represents 52 species grouped in 19 genera. For each species the original and current names, bibliographic references, type category, number of specimens, gender, Museo de La Plata code numbers, and transcription of data from labels (country, province, locality, date of collection, collector's name, and hosts) are given. Information about the state of preservation of the specimens in each series and photographs of each type species are also provided.
Bowling, Robert D.; Brewer, Michael J.; Kerns, David L.; Gordy, John; Seiter, Nick; Elliott, Norman E.; Buntin, G. David; Way, M. O.; Royer, T. A.; Biles, Stephen; Maxson, Erin
In 2013, the sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), a new invasive pest of sorghum species in North America, was confirmed on sorghum in 4 states and 38 counties in the United States. In 2015, the aphid was reported on sorghum in 17 states and over 400 counties as well as all sorghum-producing regions in Mexico. Ability to overwinter on living annual and perennial hosts in southern sorghum-producing areas and wind-aided movement of alate aphids appear to be th...
Bahder, B W; Bollinger, M L; Sudarshana, M R; Zalom, F G
Mealybugs (Hemiptera: Pseudococcidae) are economically significant agricultural pests on many different crops. Because of their small size and lack of easily visible characters for identification, determination of their taxonomic status is difficult and requires technical competency to prepare a slide-mounted specimen. The standard mounting technique does not allow for analysis of the genome of the specimen. Conversely, preparatory techniques for genetic analysis of mealybugs cause either loss of the entire individual or physical damage that can make morphology-based identification difficult. This study describes a simple protocol that does not impact physical integrity of the specimen for fixation and microscopic examination yet enables simultaneous DNA extraction for DNA-based identification of four mealybug species. All species prepared yielded high quality slide mounts, identified as Planococcus citri Risso, Pseudococcus viburni Signoret, Rhizoecus kondonis Kuwana, or Rhizoecus californicus Ferris. DNA extracted in this manner had higher purity and yield in the final eluate than in samples extracted using standard methods. DNA extracted was successfully amplified by polymerase chain reaction using primers for the cytochrome oxidase I gene and subsequently sequenced for all specimens. This protocol is likely to be applicable to other Hemiptera taxa that are preserved by slide mounting, allowing for both the preparation of a high-quality voucher specimen for morphological identification and simultaneous analysis of DNA for the same specimen. The methods used are technically less challenging than current standard procedures. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.
Presencia de Clitostethus arcuatus (Coleoptera: Coccinellidae sobre olivos infestados con Siphoninus phillyreae (Hemiptera: Aleyrodidae en Argentina On the presence of Clitostethus arcuatus (Coleoptera: Coccinellidae on olive trees infested with Siphoninus phillyreae (Hemiptera: Aleyrodidae in Argentina
María L. Gasparini
Full Text Available Se informa acerca del hallazgo de Clitostethus arcuatus (Rossi (Coleptera: Coccinellidae, Scymninae en plantas de olivo infestados con Siphoninus phillyreae (Haliday (Hemiptera: Aleyrodidae. El material se recolectó en plantaciones de olivo de los departamentos Junín, San Martín, Rivadavia y Maipú (Mendoza, Argentina durante los monitoreos de identificación de enemigos naturales de la «mosca blanca del fresno», Siphoninus phillyreae.The presence of Clitostethus arcuatus (Rossi (Coleoptera: Coccinellidae,Scymninae on olive trees infested with Siphoninus phillyreae (Haliday (Hemiptera: Aleyrodidae, is reported. Specimens were collected during a survey on natural enemies of «ash whitefly», Siphoninus phillyreae, carried out in olive plantations of Junín, San Martín, Rivadavia and Maipú (Mendoza, Argentina.
Ocorrência de Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae no Estado de Goiás Occurence of the Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae in Goiás State
Jaqueline Magalhães Pereira
Full Text Available O percevejo bronzeado Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae foi encontrado no Estado de Goiás atacando plantas de Eucalyptus camaldulensis Dehnh. e E. urophylla S. T. Blake. A detecção ocorreu nos municípios de São Luiz do Norte, São Francisco de Goiás e Goiânia.The bronze bug Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae was found in Goiás state attacking Eucalyptus camaldulensis Dehnh. e E. urophylla S. T. Blake. The insect was detected in the cities of São Luiz do Norte, São Francisco de Goiás and Goiânia.
Full Text Available Portanus dubius sp. nov. é descrita e ilustrada a partir de espécimens que foram coletados com armadilha Malaise durante um levantamento entomológico no Estado do Paraná, Brasil (PROFAUPAR.Portanus Ball: description of a new species (Hemiptera, Cicadellidae, Xestocephalinae. Portanus dubius sp. nov. is described and illustrated. The specimens were collected with Malaise trap during an entomological inventory in Paraná State, Brazil (PROFAUPAR.
Javier Garcia Gonzalez
Phytoplasmas are bacteria with a persistent propagative transmission by insect vectors that generates direct and indirect interactions among them. In order to understand these interactions for maize bushy stunt phytoplasma (MBSP) and the leafhopper vector Dalbulus maidis (Hemiptera: Cicadellidae), two research lines were addressed. The first one aimed to determine the indirect effects of maize infection by MBSP on some biological and behavioral parameters of the vector, whereas a second line ...
Full Text Available Paradasynus spinosus Hsiao, 1963 (Hemiptera:Coreidae:Dasynini, with its higher taxon, the tribe Dasynini, and the genus Paradasynus, is reported from the Korean Peninsula for the first time. The morphological information such as diagnosis and description of male/female genitalia and biological note are presented with photographs and illustrations, and the possibility of its spread in Korea as an insect pest is discussed under climate change. Keywords: Coreidae, Dasynini, New record, The Korean Peninsula
Elis José Aldana
Full Text Available En este trabajo se evidencia que si el éxito reproductivo de Rhodnius prolixus Stal está relacionado a la fuente alimentaria, entonces las necesidades biológicas del insecto son satisfechas en modos diferentes según el tipo de alternancia entre dichas fuentes de alimentación; tales diferencias son reveladas mediante los cambios en fertilidad y fecundidad del insecto. Se realizaron nueve alternancias, en cada una se suministraron dos alimentaciones, en unas se alternó la fuente de alimentación y en los controles se suministraron dos alimentaciones con la misma fuente. Las fuentes alimentarias fueron paloma, gallina y humano, esta última mediante un aparato de alimentación artificial; estas fuentes se escogieron en el supuesto que son fuentes alimentarias encontradas en los ecotopos silvestre, peri-domicilio y domicilio respectivamente. En todos los tipos de alternancia se encontró una relación lineal entre la fecundidad y el tiempo de oviposición, que la relación entre cantidad de sangre ingerida y la fecundidad varían, que la tasa de fecundidad aumenta en la segunda alimentación respecto a la primera y que la fertilidad fue superior al 95 %. Effects of alternating blood sources on fecundity and fertility of Rhodnius prolixus Stal (Heteroptera: ReduviidaeIn this work it is argued that if the reproductive parameters of Rhodnius prolixus Stal are related to the blood source upon which it feeds, then the insects biological needs must be satisfied in different ways by the alternation between blood sources, reveled through changes in the fecundity and fertility of individuals of this insect species. Nine experiments were conducted, each one consisting of two feedings, in which the blood source were either alternated or remained the same. The meal sources used were pigeon, hen and human blood, selected according to the resources found in the sylvatic, peri-domestic and domestic ecotopes respectively. It was found that the quantity of
Simmons, Alvin M; Shaaban, Abd-Rabou
The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is an important pest of vegetables and many other crops worldwide. Eight biorational insecticides (based on oil, plant derivatives, insect growth regulator and fungus) were evaluated in the field for their influence on populations of six natural enemies of B. tabaci. Natural populations of two predators [Chrysoperla carnea Stephen (Neuroptera: Chrysopidae) and Orius spp. (Hemiptera: Anthocoridae)] and two genera of parasitoids [Encarsia spp. and Eretmocerus spp. (Hymenoptera: Aphelinidae)] were evaluated in eggplant (Solanum melongena L.). Also, augmented field populations of three predators [C. carnea, Coccinella undecimpunctata L. (Coleoptera: Coccinellidae) and Macrolophus caliginosus (Wagner) (Hemiptera: Miridae)] were evaluated in cabbage (Brassica oleracea var. capitata L.), cucumber (Cucumis sativus L.) and squash (Cucurbita pepo L.). Regardless of natural enemy or crop, jojoba oil, Biovar and Neemix had the least effect on abundance of the natural enemies in comparison with the other insecticides during a 14 day evaluation period. Conversely, Admiral, KZ oil, Mesrona oil, Mesrona oil + sulfur and natural oil had a high detrimental effect on abundance of the natural enemies. These results demonstrate the differential effects of biorational insecticides for whitefly control on predators and parasitoids in the field. This article is a US Government work and is in the public domain in the USA. Published 2011 by John Wiley & Sons, Ltd.
Harley Nonato de Oliveira
Full Text Available The aim of this study was to evaluate the non-preference for oviposition Vatiga illudens (Drake, 1922 (Hemiptera: Tingidae in cassava cultivars. The following cultivars were compared: Kiriris, N-25, Fécula Branca, IAC 90, M Ecu 72 and IAC 576, preference tests for oviposition were conducted, with a choice test in semi-field conditions. An adult double V. illudens was released in the leaves of cassava of their cultivars. Allowed to feeding and oviposition of these insects for 72 hours. We evaluated the number of eggs / female / leaf, the number of droppings / couple / sheet and the preference index for oviposition. The cultivar M Ecu 72 demonstrated to be highly resistant to cassava lace bug. This study showed that there are resistance mechanisms to V. illudens in cassava cultivars, which justifies the new studies on these cultivars in breeding programs, aiming to control this pest and identification of such mechanisms.
Alves, Tavvs Micael
Soybean aphid, Aphis glycines (Hemiptera: Aphididae) is the primary insect pest of soybean in the northcentral United States. Soybean aphid may cause stunted plants, leaf discoloration, plant death, and decrease soybean yield by 40%. Sampling plans have been developed for supporting soybean aphid management. However, growers' perception about time involved in direct insect counts has been contributing to a lower adoption of traditional pest scouting methods and may be associated with the use of prophylactic insecticide applications in soybean. Remote sensing of plant spectral (light-derived) responses to soybean aphid feeding is a promising alternative to estimate injury without direct insect counts and, thus, increase adoption and efficiency of scouting programs. This research explored the use of remote sensing of soybean reflectance for detection of soybean aphids and showed that foliar insecticides may have implications for subsequent use of soybean spectral reflectance for pest detection. (Abstract shortened by ProQuest.).
Kaydan, Mehmet Bora; Benedicty, Zsuzsanna Konczné; Kiss, Balázs; Szita, Éva
In the last decades, several expeditions were organized in Europe by the researchers of the Hungarian Natural History Museum to collect snails, aquatic insects and soil animals (mites, springtails, nematodes, and earthworms). In this study, scale insect (Hemiptera: Coccomorpha) specimens extracted from Hungarian Natural History Museum soil samples (2970 samples in total), all of which were collected using soil and litter sampling devices, and extracted by Berlese funnel, were examined. From these samples, 43 scale insect species (Acanthococcidae 4, Coccidae 2, Micrococcidae 1, Ortheziidae 7, Pseudococcidae 21, Putoidae 1 and Rhizoecidae 7) were found in 16 European countries. In addition, a new species belonging to the family Pseudococcidae, Brevennia larvalis Kaydan, sp. n. and a new species of Ortheziidae, Ortheziola editae Szita & Konczné Benedicty, sp. n. are described and illustrated based on the adult female stage. Revised keys to the adult females of Brevennia and Ortheziola are presented.
Full Text Available The present study is a cladistic analysis of morphological characters focusing on the file of the mandible, the apices of the maxillae, the rupturing device on the maxillae, the internal structures of the mouthparts, and the external morphology of the labial segments as well as the distribution of labial sensilla in true water bugs (Hemiptera: Heteroptera, infraorder Nepomorpha. The study is based on data referring to sixty-two species representing all nepomorphan families (Heteroptera, together with one outgroup species representing the infraorders Gerromorpha (Mesoveliidae. The morphological data matrix consists of forty-eight characters. The present hypothesis supports the monophyly of the Nepomorpha and the monophyly of all families. The new modification in the systematic classification has been proposed: ((Nepidae + Belostomatidae, (Diaprepocoridae + Corixidae + Micronectidae, (Ochteridae + Gelastocoridae, Aphelocheiridae, Potamocoridae, Naucoridae, Notonectidae, and (Pleidae + Helotrephidae.
Full Text Available Whiteflies (Hemiptera: Aleyrodidae can cause direct and indirect damages on plants, especially vegetables. There is only limited information regarding taxonomy and population dynamic of whiteflies attacking vegetables in Indonesia. This research is conducted to identify species of whitefly collected from chili pepper, tomato, and soybean, and to study their population dynamic. The information gathered from these studies will be useful to support whitefly management in the field. Based on morphology identification of the puparium collected directly from the host plants, there were four species of whitefly identified from chili pepper, tomato, and soybean in Bogor, Cianjur, and Sukabumi, i.e. Bemisia tabaci, Aleurodicus dispersus, Trialeurodes vaporariorum, and Dialeurodes sp. The presence of B. tabaci on chili pepper and tomato was associated with virus infection that causes yellowing and leaf curl disease. This population of B. tabaci tended to increase along with plant growth and generally reached the highest population when the plant was 60-70 days after planting.
Full Text Available The paper provides a historical review of the research on Flatidae in Madagascar and indicates future prospects. While the first two species of Madagascar Flatidae were described by Guérin-Méneville (1844, it was Signoret (1860 who made the first real attempt to enhance our knowledge of the Hemiptera fauna of Madagascar by describing several additional species. Over the following century and a half, several investigators have turned their attention to this group of insects, with the final number of species recorded for the island reaching 79. Despite this long history of research, it is evident that much still remains to be done. Detailed taxonomic research will allow the natural history of Madagascar and changes in the biological diversity of its endemic ecosystems to be better understood. This paper should be considered as an introduction to a complex study on the systematics and phylogeny of worldwide Flatidae planthoppers.
Michele Aparecida Besten
Full Text Available The volatile components of the galls induced by the insect Baccharopelma dracunculifoliae (Hemiptera: Psyllidae on leaves of Baccharis dracunculifolia (Asteraceae were analyzed by gas chromatography-mass spectrometry (GC-MS and gas chromatographyflame- ionisation detection (GC-FID, and then comparison with volatile oil samples from healthy leaves collected in the vicinity. The galls produced around 3.5% of the total organic volatiles whereas healthy leaves rendered an average yield of 0.6%. The observed higher proportions of germacrene D, bicyclogermacrene, limonene, and β-pinene in the galls suggest that all these compounds are important targets in the search for natural enemies of this Psyllid. Moreover, higher relative percentages of (E-nerolidol and spathulenol were found in healthy leaves.
Gordon, T L; Haseeb, M; Kanga, L H B; Legaspi, J C
The southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae), is a serious insect pest of tomatoes in Florida. In this study, we examined the use of three species of trap crops to manage N. viridula in North Florida tomato crops in 2014 and 2015. We used striped sunflower (Helianthus annuus) (Asterales: Asteraceae) and wild game feed sorghum (Sorghum bicolor) (Poales: Poaceae) in both years, but different species of millet each year: browntop millet (Panicum ramosum) (Poales: Poaceae) in 2014 and pearl millet (Pennisetum glaucum) (Poales: Poaceae) in 2015. The number of stink bug adults collected from wild game feed sorghum exceeded the number from sunflower, and none were collected from either species of millet. Sorghum attracted a significantly higher number of adults than did striped sunflower; however, both sunflower and sorghum attracted the adults of N. viridula. Adults of the pest feed on the sorghum panicle and sunflower head (inflorescence). Although fewer stink bugs were found feeding on sunflower, the sunflower was found to be a good source of other natural enemies and pollinators and also attracted significantly greater numbers of the brown stink bug Euschistus servus (Say) (Hemiptera: Pentatomidae) (another pest of tomatoes). While this study demonstrated the effectiveness of sorghum, we recommend that sorghum be planted with another trap crop, preferably sunflower, for better preventive control of the southern green stink bug. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Sahayaraj, K. Vol 10 (2008) - Articles Ecology of Dysdercus cingulatus morphs. Abstract · Vol 9 (2007) - Articles Ecotypic variation in the biology of Acanthaspis quinquespinosa Fabricius 1781 (Hemiptera: Reduviidae: Reduviinae) from peninsular India Abstract PDF. ISSN: 1110-6859. AJOL African Journals Online.
Sônia M. F. Broglio
Full Text Available First report and morphological redescription of Teleonemia morio (Stål (Hemiptera, Tingidae in Annona squamosa L. (Annonaceae in Brazil. This is the first report of a severe attack of Teleonemia morio (Stål, 1855 (Hemiptera, Heteroptera, Tingidae on Annona squamosa L. (custard apple, causing up to 80% of losses of infested trees. In order to facilitate the identification of this insect pest, the adult female of T. morio is redescribed based on specimens collected in Palmeira dos Índios, Alagoas, Brazil.
Vinícius Soares Sturza
Full Text Available First record of larvae of Allograpta exotica Wiedemann (Diptera, Syrphidae preying on Aphis gossypii Glover (Hemiptera, Aphididae in watermelon in Brazil. Brazil is one of the largest world producers of watermelon (Citrullus lanatus Thumb. Mansf. and Aphis gossypii Glover, 1877 (Hemiptera, Aphididae is among the most important pest on this crop. Larvae of Allograpta exotica Wiedemann, 1830 (Diptera, Syrphidae were found preying on A. gossypii in watermelon crop, in Santa Maria, Rio Grande do Sul State, what represents the first report of this tritrophic association in Brazil.
Full Text Available Abstract Background With some exceptions, mitochondria within the class Insecta have the same gene content, and generally, a similar gene order allowing the proposal of an ancestral gene order. The principal exceptions are several orders within the Hemipteroid assemblage including the order Thysanoptera, a sister group of the order Hemiptera. Within the Hemiptera, there are available a number of completely sequenced mitochondrial genomes that have a gene order similar to that of the proposed ancestor. None, however, are available from the suborder Sternorryncha that includes whiteflies, psyllids and aphids. Results We have determined the complete nucleotide sequence of the mitochondrial genomes of six species of whiteflies, one psyllid and one aphid. Two species of whiteflies, one psyllid and one aphid have mitochondrial genomes with a gene order very similar to that of the proposed insect ancestor. The remaining four species of whiteflies had variations in the gene order. In all cases, there was the excision of a DNA fragment encoding for cytochrome oxidase subunit III(COIII-tRNAgly-NADH dehydrogenase subunit 3(ND3-tRNAala-tRNAarg-tRNAasn from the ancestral position between genes for ATP synthase subunit 6 and NADH dehydrogenase subunit 5. Based on the position in which all or part of this fragment was inserted, the mitochondria could be subdivided into four different gene arrangement types. PCR amplification spanning from COIII to genes outside the inserted region and sequence determination of the resulting fragments, indicated that different whitefly species could be placed into one of these arrangement types. A phylogenetic analysis of 19 whitefly species based on genes for mitochondrial cytochrome b, NADH dehydrogenase subunit 1, and 16S ribosomal DNA as well as cospeciating endosymbiont 16S and 23S ribosomal DNA indicated a clustering of species that corresponded to the gene arrangement types. Conclusions In whiteflies, the region of the
First occurrence of Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) preying on defoliating caterpillars of oil palm in the state of Para, Brazil; Primeira ocorrencia de Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) predando lagartas desfolhadoras do dendezeiro no estado do Para, Brasil
Ribeiro, Rafael C.; Lemos, Walkymario P.; Muller, Antonio A. [EMBRAPA Amazonia Oriental, Belem, PA (Brazil). Lab. de Entomologia], e-mail: email@example.com, e-mail: firstname.lastname@example.org; Muller, Antonio A. [Embrapa Amazonia Oriental, Belem, PA (Brazil). Lab. de Entomologia; Bernardino, Aline S.; Buecke, Joel [Grupo Agropalma S/A., Tailandia, PA (Brazil)
The oil palm Elaeis guineensis is usually attacked by pests, particularly, defoliating caterpillars. Between 2004 and 2006 a stinkbug predator (Asopinae) was registered preying on caterpillars of Brassolis sophorae L., Opsiphanes invirae Hubner (Lepidoptera: Nymphalidae) and Sibine spp. (Lepidoptera: Limacodidae), reducing their populations in commercial oil palm plantations in the State of Para, Brazil. Specimens of the natural enemy were collected, mounted, and identified as Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae), corresponding to the first report of the occurrence of this stinkbug attacking defoliating caterpillars of oil palm in Brazil. (author)
The silverleaf whitefly, Bemisia tabaci biotype B (Gennadius) (Hemiptera:Aleyrodidae), is a key pest of tomato (Solanum lycopersicum L.) and other vegetable crops worldwide. To combat this pest, a non-crop banker plant system was evaluated that employs a parasitoid, Encarsia sophia (Girault & Dodd) ...
The predatory lady beetle Delphastus catalinae (Horn) (Coleoptera: Coccinellidae) was evaluated as a potential biological control agent against the ficus whitefly, Singhiella simplex (Singh) (Hemiptera: Aleyrodidae), a newly-invasive pest of ficus plants. Adult D. catalinae females were starved for ...
Hodgson, Chris J; Gunawardana, D N; Richmond, J E
The genus Kalasiris Henderson & Hodgson (Hemiptera: Sternorrhyncha: Coccomorpha: Coccidae) is currently only known from New Zealand. The adult female and pupa of a new species, K. martini Hodgson & Richmond are described and illustrated below and the possible taxonomic relationships of the genus to other New Zealand genera are discussed.
Huanglongbing (HLB) is one of the most destructive disease affecting citrus plants. The causal agent is associated with the phloem-limited bacterium Candidatus Liberibacter asiaticus (CLas) spread by the Asian citrus psyllid, Diaphorina citri (Hemiptera: Liviidae). Among the control strategies for H...
The Southern Green Stink Bug (SGSB), Nezara viridula (Hemiptera: Pentatomidae) is a serious insect pest of tomatoes and numerous vegetable and fruit plants in north Florida. We evaluated three trap crops and three refuge crops to investigate their potential to be used for IPM (Integrated Pest Manag...
Silva, Leonardo D; Bonani, Jean P
This report has the objective of registering, for the first time in Brazil, the predator Stethorus (Stethorus) minutalus Gordon & Chapin (Scymninae, Stethorini). Larvae and adults were observed feeding on eggs and nymphs of the whitefly Bemisia tabaci Gennadius biotype B (Hemiptera: Aleyrodidae), on cotton plants under greenhouse condition in Piracicaba, SP. Probably, this coccinelid is an introduced species in the Country.
The tachykinin-related peptides (TRPs) are multifunctional neuropeptides found in a variety of arthropod species, including the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae). Two novel biostable TRP analogs containing multiple, sterically-hindered Aib residues were synthesized and found to exhi...
Macadamia felted coccid, Eriococcus ironsidei (Williams) (Hemiptera: Eriococcidae) was first found infesting macadamia trees in the island of Hawaii in 2005. Macadamia felted coccid infests all above-ground parts of trees to feed and reproduce. Their feeding activity distorts and stunts new growth w...
Lins, J.C.; Bueno, V.H.P.; Silva, D.B.; Sampaio, M.V.; Lenteren, van J.C.
Life table data of natural enemies are often used to understand their population dynamics and estimate their potential role in the biological control of pests. Macrosiphum euphorbiae (Thomas) (Hemiptera: Aphididae) is an important pest of several crops and its intrinsic rate of population increase
The green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae) is a major pest of agriculture worldwide that is particularly adept at evolving insecticide resistance very frequently develop insecticide resistance. Seven mechanisms that confer resistance to many insecticide types have been des...
Pre shipping dip treatments using soap, natural oils, and Isaria fumosorosea: potential biopesticides for mitigating the spread of whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) invasive insects on ornamental plants
The whitefly Bemisia tabaci (Hemiptera: Aleyodidae) is an invasive insect pest affecting different crops including vegetables, fruits, cereals, and ornamentals. The efficacy of some products such as commercial soap, natural oils and Preferal® (based on the entomopathogenic fungus Isaria fumosorosea ...
The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a destructive insect pest in the citriculture, because it is an efficient vector of the proteobacteria, ‘Candidatus Liberibacter asiaticus’ (Las), ‘Ca. L. Africanus’ (Laf), and ‘Ca. L. Americanus’ (Lam). These bacteria c...
Lee, S.; Holman, Jaroslav; Havelka, Jan
Roč. 104, č. 2 (2002), s. 447-457 ISSN 0013-8797 R&D Projects: GA AV ČR IBS5007102 Institutional research plan: CEZ:AV0Z5007907 Keywords : Hemiptera * Aphididae * Megoura Subject RIV: EG - Zoology Impact factor: 0.392, year: 2002
A revision of the genus Macrosiphoniella del Guercio (Hemiptera: Sternorrhyncha: Aphididae) from the Korean peninsula, part I: Subgenera Asterobium, Chosoniella, Papillomyzus, Phalangomyzus, Sinosiphoniella
Holman, Jaroslav; Lee, S.; Havelka, Jan
Roč. 108, č. 1 (2006), s. 174-197 ISSN 0013-8797 R&D Projects: GA AV ČR(CZ) IBS5007102 Institutional research plan: CEZ:AV0Z5007907 Keywords : Hemiptera * Aphididae * Macrosiphoniella Subject RIV: EG - Zoology Impact factor: 0.394, year: 2006
Full Text Available Resumen. La taxonomía y sistemática de la subfamilia Triatominae (Heteroptera, Reduviidae se basan principalmente en caracteres biométricos y morfológicos de las formas adultas y, en algunos casos, de las ninfas. La Morfometría Geométrica es capaz de descomponer la forma en sus componentes tamaño isométrico y conformación. En el presente trabajo se utilizó laMorfometría Geométrica como herramienta de análisis de la configuración geométrica que resulta de la unión de los extremos del borde corial y del collar (configuración borde corial-collar de los huevos eclosionados de cinco especies del género Rhodnius Stal. Los huevos se observaron por Microscopía Electrónica de Barrido y las imágenes digitalizadas fueron analizadas morfogeométricamente. Estudiando el tamaño geométrico de la configuración borde corial-collar, se halló que no existen diferencias estadísticamente significativas entre las cinco especies deTriatominos. En cuanto a la conformación, se determinaron diferencias entre las especies al ser sometidas a un análisis discriminante. Se encontró además que la variación del tamaño contribuye a la variación en la conformación, es decir, efecto alométrico. Los resultados obtenidos indican que la conformación de la configuración geométrica “borde corial-collar” de los huevos de Rhodnius podría ser utilizada como herramienta taxonómica para este grupo. Morfometria geométrica da borda corial e colarinho de ovos de cinco espécies do Gênero Rhodnius (Heteroptera Reduviidae, Triatominae.Resumo. A taxonomia e sistemática da subfamília Triatominae (Heteroptera Reduviidae esta baseada principalmente em caracteres biométricos e morfológicos das formas adultas, e em alguns casos, das ninfas. A morfometria geométrica é capaz de descompor a forma em seus componentes, tamanho isométrico e conformação. No presente trabalho utilizou-se a morfometria geométrica como ferramenta de análise da configura
Análise das relações taxonômicas e sistemáticas entre espécies de triatomíneos (Hemiptera, Reduviidae de colônias mantidas pelo Serviço Especial de Saúde de Araraquara, inferida de seqüências do 16S rDNA mitocondrial Taxonomic and systematic analysis among triatomine bug species (Hemiptera, Reduviidae from colonies of the Special Health Service of Araraquara (SESA, inferred from 16S rDNA mitocondrial sequences
Walter Ceretti Junior
Full Text Available Foram analisadas seqüências de nucleotídeos do gene 16S do rDNA mitocondrial em 14 populações de triatomíneos mantidos em colônias no insetário SESA de Araraquara- SP, comparando-as com seqüências do mesmo gene disponíveis no GenBank. Os fragmentos variaram de 311 a 317 pb com baixa variação intra-específica entre as distâncias genéticas (0% a 0,6%, exceto para os relacionamentos entre espécimes de Triatoma sordida (1% e espécimes de T. brasiliensis (1,3% atribuídos a populações geográficas diferentes. A parafilia de Rhodniini e do gênero Panstrongylus foi evidenciada pelas analises, confirmando resultados anteriores entre estes e os estreitos relacionamentos de R. prolixus com R. robustus e de T. infestans e T. platensis. O relacionamento entre T. maculata e T. pseudomaculata não foi solucionado, uma vez que, esses táxons apareceram tanto em monofilia quanto em parafilia: T. pseudomaculata (SESA está agrupado com T. maculata (seqüência do GenBank e associados a T . brasiliensis (SESA, enquanto T. maculata (SESA aparece agrupado com T. pseudomaculata do SESA e do GenBank. Os resultados evidenciam a utilidade do gene 16S como marcador de espécies de triatomíneos e sua importância em questões de sistemática e taxonomia. Há necessidade de novos estudos envolvendo outros marcadores associados a caracteres sistemáticos clássicos de morfologia, ecologia e comportamento para decisões sistemáticas adequadas uma vez, que teriam impacto não apenas sistemático mas, para as estratégias de controle.Nucleotide sequences of mitocondrial 16S rDNA gene were analyzed in 14 populations of triatomine bugs from colonies maintained by SESA, Araraquara, São Paulo, Brazil, comparing them with sequences of same gene found in the GenBank. The fragments varied from 311 to 317 bp, with low intra-specific genetic distance (0% to 0.6%, with exception of the relationship among Triatoma sordida specimens (1% and T. brasiliensis specimens (1.3% that were attributed to different geographical populations. The paraphily of Rhodniini and Panstrongylus genus was evidenced by this analyses, confirming previous results between these and the narrow relationships of R. prolixus with R. robustus and of T. infestans with T. platensis. The relationship between T. maculata and T. pseudomaculata has not been resolved, since these taxa appeared both in monophyly and as in paraphyly: T. pseudomaculata (SESA is grouped with T. maculata (sequence of GenBank and the associated T. brasiliensis (SESA, while T. maculata (SESA appears grouped with T. pseudomaculata of SESA and GenBank. The results evidence the utility of the gene 16S as molecular marker in the species of triatomine bugs and its importance in systematic and taxonomy questions. There is a necessity of new studies including new molecular markers associated with classic systematic characters of morphology, ecology and behavior to adjust systematic decisions since those will be not of only systematic impact but, for new strategies of control.
Becerra, Violeta; González, Marcela; Herrera, María Eugenia; Miano, José Luis
Planococcus ficus Signoret es un insecto perteneciente al orden Hemiptera, familia Pseudococcidae, cuya población ha aumentado en los últimos años en Mendoza. Ataca gran variedad de hospederos y está distribuido en las principales zonas vitícolas del mundo. Su acción disminuye el vigor general de las plantas, perjudica la calidad de los frutos y las características organolépticas de los vinos elaborados con racimos infestados. El objetivo de este trabajo fue realizar estudios bioecológic...
Sartiami, Dewi; Watson, Gillian W.; Mohamad Roff, M. N.; Idris, A. B.
A survey of mealybugs (Hemiptera: Coccomorpha: Pseudococcidae) attacking the national flower of Malaysia, Hibiscus rosa-sisnensis L. and Hibiscus spp. (Malvaceae) was conducted in Selangor and Kuala Lumpur, Malaysia, from January to March 2016. Adult females were mounted on microscope slides in Canada balsam. The five species identified were Ferrisia dasylirii (Cockerell), Maconellicoccus hirsutus (Green), Paracoccus marginatus Williams and Granara de Willink, Phenacoccus solenopsis (Tinsley) and Pseudococcus jackbeardsleyi Gimpel & Miller. Two of these, the invasive species Ferrisia dasylirii and P. solenopsis were introduced and first recorded in Malaysia.
Marsaro Júnior, A L; Peronti, A L B G; Costa, V A; Morais, E G F; Pereira, P R V S
Lecanodiaspis dendrobii Douglas, 1892 (Hemiptera: Coccoidea: Lecanodiaspididae) and the associated parasitoid Cephaleta sp. (Hymenoptera: Pteromalidae) are reported for the first time in Brazil. Specimens of this scale insect were collected on branches and stems of Acacia mangium Willd., Leucaena leucocephala (Lam.) de Wit (Fabaceae), Morus nigra L. (Moraceae), Citrus reticulata Blanco (Rutaceae), Tectona grandis L. f. (Verbenaceae), Anacardium occidentale (Anacardiaceae), Annona squamosa L. and Xylopia aromatica (Lam.) Mart. (Annonaceae), in three municipalities of the Roraima state. All plants here mentioned are recorded for the first time as a host for L. dendrobii. Morphological characters of L. dendrobii and symptoms presented by the host plants infested by this pest are included in this work.
Wang, Zhu-Hong; Huang, Jian; Polaszek, Andrew
Three new species of Baeoentedon Girault (Hymenoptera: Eulophidae) are described from China, Baeoentedon balios Wang, Huang & Polaszek sp. nov., Baeoentedon bouceki Wang, Huang & Polaszek sp. nov. and Baeoentedon virgatus Wang, Huang & Polaszek sp. nov. Both female and male of Baeoentedon balios were reared from the whitefly Pealius spina (Singh) (Hemiptera: Aleyrodidae) on the bodhi tree Ficus religiosa L. (Urticales: Moraceae). The male and the whitefly host association of Baeoentedon are recorded for the first time. A key is also provided to females of the world species of the genus.
Adrienne de Paiva Fernandes
Resumo: Percevejos fitófagos (Hemiptera, Pentatomidae) são as principais pragas de colheitas economicamente importantes ao redor do mundo, como por exemplo soja, arroz, coco, café, entre outras. Apesar da grande quantidade de informação sobre as espécies-praga, seu dano potencial nas plantas de importância econômica e as formas de controle usadas, fazem com que o impacto dessas pragas na produção de colheitas permaneça em níveis indesejáveis. A caracterização ultra-estrutural da espermiogênes...
Full Text Available A new genus and species of primitive cicada (Hemiptera: Tettigarctidae is described from the early Miocene of southern New Zealand. Paratettigarcta zealandica gen. et sp. n. is the first cicada (Cicadoidea fossil from New Zealand and exhibits wing venation patterns typical for the subfamily Tettigarctinae. It differs from other fossil taxa and the extant genus Tettigarcta in the early divergence of CuA2 from the nodal line in the forewing, its parallel-sided subcostal cell, the early bifurcation of vein M and long apical cells of the hindwing, and in wing pigmentation patterns.
Full Text Available As a major noncoding fragment, the control region (CR of mtDNA is responsible for the initiation of mitogenome transcription and replication. Several structural features of CR sequences have been reported in many insects. However, comprehensive analyses on the structural organization and phylogenetic utility, as well as the role of tandem replications (TRs on length variation, high A+T content, and shift of base skew of CR sequences are poorly investigated in hemipteran insects. In this study, we conducted a series of comparative analyses, using 116 samples covering all 11 infraorders of the five currently recognized monophyletic groups in the Hemiptera. Several structural elements (mononucleotide stretches containing conserved sequence blocks (CSBs, TRs, and GA-rich region were identified in the mitochondrial control region in hemipteran insects, without showing a consistent location. The presence and absence of certain specific structural elements in CR sequences show the various structural organizations of that segment among the five monophyletic groups, which indicates the diversification of the control region’s structural organization in Hemiptera. Among the many groups within Hemiptera, eight monophyletic groups and three consistent phylogenetic trees were recovered, using CSBs datasets by maximum likelihood and Bayesian methods, which suggests the possible utility of CR sequences for phylogenetic reconstruction in certain groups of Hemiptera. Statistical analyses showed that TRs may contribute to the length variation, high AT content, and the shift of base skewing of CR sequences toward high AT content in the Hemiptera. Our findings enrich the knowledge of structural organization, phylogenetic utility, and roles of tandem replication of hemipteran CR, and provide a possible framework for mitochondrial control region analyses in hemimetabolous insects.
E. S. Araujo
Full Text Available Abstract This study provides the first contribution of the biology and life table of Aphis forbesi Weed, 1889 (Hemiptera: Aphididae, an important strawberry pest throughout the world. This species lives in the crown and leaf petioles of the plant. It is difficulty to rear this species in laboratory due to protocooperation with ants observed only in the field. We studied the life cycle of A. forbesi on the leaves of the Albion strawberry cultivar at 25 ± 2 °C, 60 ± 10% relative humidity, and a 12-h photophase. The experiment was randomised with 100 replicates. The parameters of the fertility life table were calculated using TabVida. In the population studied, 25% and 46% had four and three instars, respectively. A mean of 1.43 nymphs per female per day was generated. The mean reproductive period was seven days and the mean longevity was 10 days. In every 11 days there is a generation of A. forbesi, where each female has the potential to generate between 6 to 9 individuals daily, increasing its population by 1.2 times. The average life cycle was 16.8 days. High viability observed in all instars and the resulting values of R0, rm and λ suggest that A. forbesi has the capacity to increase their numbers in a short period of time, while generating high populations in strawberry crops, requiring differential management.
Full Text Available Life table studies are essential tools for understanding population dynamics. The life table parameters of Aphis gossypii Glover (Hemiptera: Aphididae feeding on the host plant, Hibiscus syriacus L. were studied under laboratory (25±1°C and relative humidity of 65±5% and a photoperiod of 16L : 8D h and field conditions (23-43°C, and relative humidity of 27-95%. The data were analysed using the age-stage, two-sex life table theory. The life table studies were started with 50 and 40 nymphs in laboratory and field conditions, respectively. Under laboratory conditions, A. gossypii reared on H. syriacus had a higher survival rate, fecundity, and longevity than those reared under field conditions. When reared under field conditions, A. gossypii had a longer nymphal developmental time, shorter adult longevity, and lower fecundity than those reared under laboratory conditions. The intrinsic rate of increase (r, net reproductive rate (R0, and the finite rate of increase (λ under laboratory conditions, were higher than those obtained under field conditions. Nevertheless, there were no significant differences in the mean generation time T (days between field and laboratory conditions. In the present study, the results clearly showed that life table parameters of A. gossypii were significantly different under field and laboratory conditions. These results could help us to understand the A. gossypii population dynamics under field conditions. The results could also help us make better management decisions for economically important crops
Su, Qi; Oliver, Kerry M; Pan, Huipeng; Jiao, Xiaoguo; Liu, Baiming; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Xu, Baoyun; White, Jennifer A; Zhou, Xuguo; Zhang, Youjun
Bacterial symbionts infect most insect species, including important pests such as whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), and often exert important effects on host ecology. The facultative symbiont Hamiltonella is found at high frequencies in the B. tabaci MED (type: Mediterranean-MED) in China. The prevalence of this symbiont in natural populations suggests beneficial effects of infection or manipulation of host reproduction. To date, however, no empirical studies on the biological role of Hamiltonella on the host B. tabaci have been reported. Here, we investigated the effects of Hamiltonella infection on the sex ratio and several fitness parameters in B. tabaci MED by comparing Hamiltonella-infected whiteflies with Hamiltonella-free ones. We found that Hamiltonella-infected whiteflies produced significantly more eggs, exhibited significantly higher nymphal survival, faster development times, and larger adult body size in comparison with Hamiltonella-free whiteflies, while no evidence of reproductive manipulation by Hamiltonella were found in B. tabaci MED. In conclusion, Hamiltonella infection substantially enhanced B. tabaci MED performance. This beneficial role may, at least partially, explain the high prevalence of Hamiltonella in B. tabaci MED populations and may also contribute to their effectiveness in spread of the plant pathogens tomato yellow leaf curl virus.
Nondillo, Aline; Andzeiewski, Simone; Bello Fialho, Flávio; Bueno, Odair Correa; Botton, Marcos
Linepithema micans (Forel) (Hymenoptera: Formicidae) is the main ant species responsible for dispersal of Eurhizococcus brasiliensis (Wille) (Hemiptera: Margarodidae), a root scale that damages grapevines in southern Brazil. The effects of different formulations of toxic baits based on boric acid and hydramethylnon to control L. micans and E. brasiliensis were evaluated. Toxic baits with boric acid (1.0%) mixed in different concentrations of inverted sugar (20%, 30%, and 40%), and hydramethylnon, mixed with sardines (paste), cassava flour and peanut, brown sugar (sucrose), or sardine oil-based gel, were evaluated in a greenhouse and in the field. In the greenhouse experiment, the number of foraging ants was significantly reduced in the pots where the hydramethylnon in sardine paste (Solid S), sardine oil-brown sugar-based gel (GEL SAM), and peanut oil-brown-sugar gel (GEL AM) formulations were applied. The GEL SAM toxic bait effectively reduced the infestation of L. micans, and could be used for indirect control of E. brasiliensis on young grapevines. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Pan, Hongsheng; Liu, Bing; Lu, Yanhui; Desneux, Nicolas
The genus Adelphocoris (Hemiptera: Miridae) is a group of important insect pests of Bt cotton in China. The three dominant species are A. lineolatus, A. suturalis, and A. fasciaticollis, and these species have different population dynamics. The causal factors for the differences in population dynamics have not been determined; one hypothesis is that humidity may be important for the growth of Adelphocoris populations. In the laboratory, the demographic parameters of the three Adelphocoris species were compared when the mirid bugs were subjected to various levels of relative humidity (40, 50, 60, 70 and 80% RH). Middle to high levels of RH (60, 70 and 80%) were associated with higher egg and nymph survival rates and increased adult longevity and female fecundity. Lower humidity levels (40 and 50% RH) had negative effects on the survival of nymphs, adult longevity and fecundity. The intrinsic rate of increase (rm), the net reproductive rate (R0) and the finite rate of increase (λ) for each Adelphocoris species increased with increasing RH. Significant positive relationships were found between RH and the life table parameters, rm, R0 and λ for the three Adelphocoris species. These results will help to better understand the phenology of the three Adelphocoris species, and the information can be used in population growth models to optimize pest forecasting and management strategies for these key pests.
Full Text Available Host stage preference, functional response and mutual interference of Diaeretiella rapae (McIntosh (Hymenoptera: Braconidae: Aphidiinae on Diuraphis noxia (Mordvilko (Hemiptera: Aphididae were investigated under defined laboratory conditions (20±1°C; 60±5% relative humidity; 16 h light/8 h dark photoperiod. Nicholson’s model and linear regression were used to determine per capita search-efficiency and the interference coefficient, respectively. There was a significant difference between the rates of parasitism on different stages of D. noxia. The highest parasitism percentage was observed on the third instar nymphs of D. noxia in both choice and no-choice preference tests. Results of logistic regression revealed a type II functional response. The estimated values of search-efficiency (a and handling time (Th were 0.072 h-1 and 0.723 h, respectively. The maximum attack rate was calculated to be 33.22. The per capita search-efficiency decreased from 0.011 to 0.004 (h-1 as parasitoid densities increased from 1 to 8. Therefore, different host-parasitoid ratios can affect the efficacy of D. rapae.
Stamm, M D; Baxendale, F P; Heng-Moss, T M; Siegfried, B D; Blankenship, E E; Gaussoin, R E
The western chinch bug, Blissus occiduus Barber (Hemiptera: Blissidae), has emerged as a serious pest of buffalograss, Buchlod dactyloides (Nuttall) Engelmann. In general, neonicotinoid insecticides effectively control a variety of turfgrass insects, particularly phloem-feeding pests. However, because of well documented inconsistencies in control, these compounds are generally not recommended for chinch bugs. This study was designed to document the contact and systemic toxicity of three neonicotinoid insecticides (clothianidin, imidacloprid, and thiamethoxam) to B. occiduus. In contact bioassays, thiamethoxam was approximately 20-fold less toxic than clothianidin or imidacloprid to B. occiduus nymphs and three-fold more toxic to adults. In adult systemic bioassays, thiamethoxam was up to five-fold more toxic than clothianidin or imidacloprid. Interestingly, thiamethoxam was significantly more toxic to adults than to nymphs in both contact and systemic bioassays. This was not observed with clothianidin or imidacloprid. Bifenthrin, used for comparative purposes, exhibited 1844-fold and 122-fold increase in toxicity to nymphs and adults, respectively. These results provide the first documentation of the relative toxicity of these neonicotinoid insecticides to B. occiduus.
Harrison, Katharine V; Preisser, Evan L
The pea aphid Acyrthosiphon pisum : Harris (Hemiptera: Aphididae) is a phloem-feeding insect whose antipredator defenses include kicking, walking away, and dropping from the plant. Aphid dropping, a risky and energetically costly antipredator behavior, can be increased by the release of aphid alarm pheromone; there is also evidence that insect density and plant health can affect the likelihood of aphids engaging in this behavior. We investigated whether interactions between alarm cues, insect density, and plant health can alter the dropping behavior of aphids in response to an artificial disturbance. The presence of the alarm pheromone E-β-farnesene resulted in a nearly 15-fold increase in aphid dropping behavior; the other two factors, however, did not affect dropping and none of the two- or three-way interactions were significant. This was surprising because aphids affected plant health: production of new plant biomass after 5 d of exposure to high aphid densities was 50% lower than in the control treatment. This research adds to our understanding of the factors affecting aphid antipredator behavior; the fact that neither aphid density nor feeding period impacted dropping may reflect the high energetic costs of this activity and an unwillingness to use it in any but the riskiest situations. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.
Bailey, Sebastian; Percy, Diana M; Hefer, Charles A; Cronk, Quentin C B
Recent studies show that galling Hymenoptera and Diptera are able to synthesize the plant hormone indole-3-acetic acid (auxin) from tryptophan and that plant response to insect-produced auxin is implicated in gall formation. We examined the leaf transcriptome of galled and ungalled leaves of individuals of the Hawaiian endemic plant Metrosideros polymorpha (Myrtaceae) subject to infestation by psyllid (Hemiptera) gall-makers in the genus Trioza (Triozidae). Transcript libraries were sequenced using Illumina technology and the reads assembled de novo into contigs. Functional identification of contigs followed a two-step procedure, first identifying contigs by comparison to the completely sequenced genome of the related Eucalyptus, followed by identifying the equivalent Arabidopsis gene using a pre-computed mapping between Eucalyptus and Arabidopsis genes. This allowed us to use the rich functional annotation of the Arabidopsis genome to assess the transcriptional landscape of galling in Metrosideros. Comparing galled and ungalled leaves, we find a highly significant enrichment of expressed genes with a gene ontology (GO) annotation to auxin response in the former. One gene consistently expressed in all galled trees examined but not detected in any libraries from ungalled leaves was the Metrosideros version of SMALL AUXIN UPREGULATED (SAUR) 67 which appears to be a marker for leaf-galling in Metrosideros. We conclude that an auxin response is involved in galling by Metrosideros psyllids. The possibility should therefore be considered that psyllids (like other insects examined) are able to synthesize auxin.
Saccaggi, D L; Krüger, K; Pietersen, G
Molecular species identification is becoming more wide-spread in diagnostics and ecological studies, particularly with regard to insects for which morphological identification is difficult or time-consuming. In this study, we describe the development and application of a single-step multiplex PCR for the identification of three mealybug species (Hemiptera: Pseudococcidae) associated with grapevine in South Africa: Planococcus ficus (vine mealybug), Planococcus citri (citrus mealybug) and Pseudococcus longispinus (longtailed mealybug). Mealybugs are pests on many commercial crops, including grapevine, in which they transmit viral diseases. Morphological identification of mealybug species is usually time-consuming, requires a high level of taxonomic expertise and usually only adult females can be identified. The single-step multiplex PCR developed here, based on the mitochondrial cytochrome c oxidase subunit 1 (CO I) gene, is rapid, reliable, sensitive, accurate and simple. The entire identification protocol (including DNA extraction, PCR and electrophoresis) can be completed in approximately four hours. Successful DNA extraction from laboratory and unparasitized field-collected individuals stored in absolute ethanol was 97%. Specimens from which DNA could be extracted were always correctly identified (100% accuracy). The technique developed is simple enough to be implemented in any molecular laboratory. The principles described here can be extended to any organism for which rapid, reliable identification is needed.
Bing, Xiao-Li; Yang, Jiao; Zchori-Fein, Einat; Wang, Xiao-Wei; Liu, Shu-Sheng
Bemisia tabaci (Hemiptera: Aleyrodidae) is a species complex containing >28 cryptic species, some of which are important crop pests worldwide. Like many other sap-sucking insects, whiteflies harbor an obligatory symbiont, "Candidatus Portiera aleyrodidarum," and a number of secondary symbionts. So far, six genera of secondary symbionts have been identified in B. tabaci. In this study, we report and describe the finding of an additional bacterium in the indigenous B. tabaci cryptic species China 1 (formerly known as B. tabaci biotype ZHJ3). Phylogenetic analysis based on the 16S rRNA and gltA genes showed that the bacterium belongs to the Alphaproteobacteria subdivision of the Proteobacteria and has a close relationship with human pathogens of the genus Orientia. Consequently, we temporarily named it Orientia-like organism (OLO). OLO was found in six of eight wild populations of B. tabaci China 1, with the infection rate ranging from 46.2% to 76.8%. Fluorescence in situ hybridization (FISH) of B. tabaci China 1 in nymphs and adults revealed that OLOs are confined to the bacteriome and co-occur with "Ca. Portiera aleyrodidarum." The vertical transmission of OLO was demonstrated by detection of OLO at the anterior pole end of the oocytes through FISH. Quantitative PCR analysis of population dynamics suggested a complex interaction between "Ca. Portiera aleyrodidarum" and OLO. Based on these results, we propose "Candidatus Hemipteriphilus asiaticus" for the classification of this symbiont from B. tabaci.
Full Text Available Hibiscus mealybug, Maconellicoccus hirsutus (Hemiptera: Pseudococcidae, is the major pest of many vegetables, fruits, crops, and ornamental plants causing losses to the farmers and its control has been an issue of significance in the pest management. This study was aimed at evaluating different concentrations (0.06%, 0.1%, and 0.14% of Telsta, Advantage, Talstar, Imidacloprid, and their mixtures against hibiscus mealybug in the Laboratory of Systematics and Pest Management at University of Gujrat, Pakistan. The toxic effect was evaluated in the laboratory bioassay after 24 and 48 h of the application of insecticides. The highest mortality (95.83% was shown by Talstar and Talstar + Imidacloprid at the concentration of 0.14% after 48 h followed by Advantage + Talstar with 87.50% mortality at 0.14% concentration after 48 h of application. The study also showed that the least effective treatment observed was Advantage + Telsta with no mortality after 24 h and 25% mortality after 48 h at 0.14% concentration. The study revealed that the concentration 0.14% was highly effective in lowering the mealybug population and insecticide mixtures were effective in reducing mealybug density. The study emphasizes the use of such insecticide mixtures to develop better management strategy for mealybug populations attacking ornamental plants. However effects of such insecticide mixtures on other organisms and biological control agents should be checked under field conditions.
Watanabe, Kisaki; Shimizu, Nobuhiro
Although the nymphs of Corythucha marmorata form clusters on the undersides of host plant leaves, as frequently observed for Hemiptera, the adults are scattered in the vicinity of the nymph population. By investigating the biological activities of volatile secretions from the adult, we found that the secretions activated male mounting behaviour. A chemical analysis revealed that borneol was a common component of the secretions from both sexes. The absolute configuration of the natural product was the (+)-enantiomer of borneol and the optical isomer was undetectable. Although (+)-borneol showed significant sex pheromone activity against males, the antipode (-)-borneol also induced sex pheromone activity, albeit only slightly. Males may not have a strict identification mechanism based on stereochemistry. To verify the origin of this sex pheromone, we analysed the components of the essential oil of the leaves of Solidago canadensis L. (Compositae: Asteraceae), a host plant; bornyl acetate was detected to be a major component. The plant-produced bornyl acetate had different stereochemistry from the sex pheromone. The results suggested that the adults do not utilise the secondary metabolites of plants but biosynthesise this sex pheromone themselves. This is the first report on sex pheromone identification in Tingidae.
Doan Thi The; Nguyen Thuy Khanh; Vo Kim Lang; Cao Van Chung; Tran Thien An; Nguyen Hoang Hanh Thi
Since 2008 APHIS/USDA approved to import dragon fruit into the United States from Vietnam if fruits are treated with the minimum absorbed dose of 400 Gy to control fruit flies and mealybugs. However, a lower dose could be accepted if released data is enough to demonstrate that it is efficient to inhibit the development and stop the reproduction of adult females for three species of mealybugs (Order: Hemiptera; Family: Pseudococcidae) infesting on dragon fruit. Four development stages including 1 st , 2 nd , 3 rd instars and adult of Dymicoccus neobrevipes by isolating and rearing in the laboratory conditions were irradiated in Co-60 source gamma with dosages of 100, 200, 300 and 400 Gy. The main purposes of the study are to find the most tolerant stage and to determine the most optimal dose to control D. neobrevipes. The initial obtained results showed that the adult stage is the most radiotolerant and the dose of 200 Gy could be an effective dose to inhibit development and to control reproduction of D. neobrevipes. (author)
Fornasiero, D; Pavan, F; Pozzebon, A; Picotti, P; Duso, C
The leafhopper Empoasca vitis (Göthe) (Hemiptera: Cicadellidae) feeds on veins of grapevine leaves, mainly on the phloem, causing physiological injury, color change and drying of leaf margins, yield and sugar content reduction. The relative infestation level (i.e., the probability that a plant is attacked by herbivores) of E. vitis on different grapevine cultivars and their sensitivity (i.e., the incidence of symptoms expression in response to herbivore feeding or other stimuli) to this pest were studied over four years in two vineyards located in northeastern Italy. Some cultivars (e.g., Carménère and Sauvignon Blanc) were usually more infested than others (e.g., Cabernet Sauvignon and Pinot Gris), although some differences were observed among years and sites. The sensitivity varied among cultivars, i.e., some of them showed more symptoms than expected on the basis of infestation levels (e.g., Carménère and Merlot), in contrast with others (e.g., Rhine Riesling and Chardonnay). Information obtained can be used within the framework of integrated pest management in vineyards. Action thresholds should differ on the basis of sensitivity. Sampling must first be carried out on the most susceptible cultivar and, if the action threshold is exceeded, it should be extended to the remaining cultivars based on their decreasing relative infestation level. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Lima, Carlos H O; Sarmento, Renato A; Galdino, Tarcísio V S; Pereira, Poliana S; Silva, Joedna; Souza, Danival J; Dos Santos, Gil R; Costa, Thiago L; Picanço, Marcelo C
Spatiotemporal dynamics studies of crop pests enable the determination of the colonization pattern and dispersion of these insects in the landscape. Geostatistics is an efficient tool for these studies: to determine the spatial distribution pattern of the pest in the crops and to make maps that represent this situation. Analysis of these maps across the development of plants can be used as a tool in precision agriculture programs. Watermelon, Citrullus lanatus (Thunb.) Matsum. and Nakai (Cucurbitales: Cucurbitaceae), is the second most consumed fruit in the world, and the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is one of the most important pests of this crop. Thus, the objective of this work was to determine the spatiotemporal distribution of B. tabaci in commercial watermelon crops using geostatistics. For 2 yr, we monitored adult whitefly densities in eight watermelon crops in a tropical climate region. The location of the samples and other crops in the landscape was georeferenced. Experimental data were submitted to geostatistical analysis. The colonization of B. tabaci had two patterns. In the first, the colonization started at the outermost parts of the crop. In the second, the insects occupied the whole area of the crop since the beginning of cultivation. The maximum distance between sites of watermelon crops in which spatial dependence of B. tabaci densities was observed was 19.69 m. The adult B. tabaci densities in the eight watermelon fields were positively correlated with rainfall and relative humidity, whereas wind speed negatively affected whiteflies population.
Full Text Available The genus Adelphocoris (Hemiptera: Miridae is a group of important insect pests of Bt cotton in China. The three dominant species are A. lineolatus, A. suturalis, and A. fasciaticollis, and these species have different population dynamics. The causal factors for the differences in population dynamics have not been determined; one hypothesis is that humidity may be important for the growth of Adelphocoris populations. In the laboratory, the demographic parameters of the three Adelphocoris species were compared when the mirid bugs were subjected to various levels of relative humidity (40, 50, 60, 70 and 80% RH. Middle to high levels of RH (60, 70 and 80% were associated with higher egg and nymph survival rates and increased adult longevity and female fecundity. Lower humidity levels (40 and 50% RH had negative effects on the survival of nymphs, adult longevity and fecundity. The intrinsic rate of increase (rm, the net reproductive rate (R0 and the finite rate of increase (λ for each Adelphocoris species increased with increasing RH. Significant positive relationships were found between RH and the life table parameters, rm, R0 and λ for the three Adelphocoris species. These results will help to better understand the phenology of the three Adelphocoris species, and the information can be used in population growth models to optimize pest forecasting and management strategies for these key pests.
Lamp, William O; Miranda, Daniel; Culler, Lauren E; Alexander, Laurie C
Although potato leafhopper, Empoasca fabae (Harris) (Hemiptera: Cicadellidae), is highly polyphagous, classic host studies do not recognize grapevines (Vitis spp.), as suitable hosts. Recently, injury has been reported and reproduction documented within grape vineyards, suggesting a host expansion for the leafhopper. To document this apparent expansion in host use, we determined whether grape plants were suitable hosts for potato leafhopper reproduction, measured the consequence of feeding injury on gas exchange rates of grape leaves, and compared the susceptibility to feeding injury among cultivars. We found that potato leafhopper adults survived equally well on grape (Vitis vinifera L.), alfalfa (Medicago sativa L.), and fava bean (Vicia faba L.). The total number of offspring was greater on fava bean but did not differ between alfalfa and grape. Injury to grapevines was assessed by measuring gas exchange responses of leaves in field cages and in greenhouse tests. We found marginally significant declines in photosynthesis and transpiration rates in the field (9.6 and 13.2%, respectively), and much stronger effects in greenhouse tests (ranging between 22 and 52%). Our results verify that Vitis is a suitable host, and that potato leafhopper is capable of injuring its gas exchange physiology. We discuss possible explanations for the host expansion, and its potential to damage commercial grapevines.
Efrain de Santana Souza
Full Text Available Nezara viridula (L. (Hemiptera: Pentatomidae is a cosmopolitan insect that causes economic damages to several cultures, in particular soybeans (Glycine max [L.] Merr. Among the techniques that involve Integrated Pest Management, the resistance of plants is pointed as a tool of great value and can contribute to the reduction of populations of insects. The feeding preferences of adults of southern green stink bug (N. viridula, and the attractiveness of soybean genotypes were evaluated under laboratory conditions to detect the most resistant material against attack from this insect. A choice test, using mature grains and green pods of the genotypes was carried out, in which the number of individuals attracted in different periods was counted. Feeding preference was evaluated in the choice tests using green pods and the number of pricks and the average time spent feeding by pricks were evaluated. In addition, texture and trichome density in the green pods were evaluated. The mature grains of 'TMG 117RR' and 'TMG 121RR' were less attractive to the adults of N. viridula. Regarding the green pods, 'IAC 17' and PI 227687 were less attractive; 'IAC 17' and 'IAC PL1' were less consumed, indicating the feeding non-preference as a resistance mechanism. 'IAC 17', 'TMG-117RR' and PI 227687 presented high levels of trichome density, and in 'IAC 17' this morphological characteristic was considered to be the main resistance factor against N. viridula. These results may be useful for breeding programs that focus on the resistance of soybeans to insects.
Marcelino, M C S; Barbosa, J C
The psyllid Triozoida limbata (Enderlein) (Hemiptera: Triozidae) is a major pest in guava, feeding primarily on new shoots. Despite its importance, there are no studies on the spatial distribution of T. limbata on guava. Such studies are needed to establish sequential sampling plans for decision making in pest control. Thus, an experiment was carried out in a 9-year-old commercial guava orchard divided into 100 sampling units or plots. Double-sided yellow sticky traps were placed on one plant per plot (sample unit) to capture and monitor T. limbata adults from April 2011 to May 2012. To determine the insect distribution in the area, we calculated the variance-to-mean ratio index (I), the Morisita index (I δ ), Green's coefficient (Cx), and the k exponent of the negative binomial distribution. Most of the samples showed that the adults had a moderate to highly aggregated distribution. Statistical models were also used to study the pest spatial distribution by fitting the number of adults captured to the Poisson and negative binomial distributions. The negative binomial distribution model best fitted the data of the number of adult psyllids captured by the traps, which is consistent with an aggregated distribution.
Barman, Jagadish Chandra; Campbell, Stuart A; Zeng, Xinnian
Intercropping can reduce agricultural pest incidence, and represents an important sustainable alternative to conventional pest control methods. Understanding the ecological mechanisms for intercropping could help optimize its use, particularly in tropical systems which present a large number of intercropping possibilities. Citrus is threatened worldwide by greening disease (huanglongbing, HLB) vectored by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae). Control of HLB and citrus psyllid can be partially achieved through intercropping with guava, Psidium guajava L., but the mechanisms remain unclear. We tested the hypothesis that guava olfactory cues affect psyllid behavior by altering the attractiveness of citrus through plant-plant interactions. In choice and no-choice cage experiments, psyllid settlement was reduced on citrus shoots that had been exposed to guava shoot odors for at least 2 h. In Y-tube olfactometer experiments, psyllids oriented to odors of unexposed, compared with guava-exposed, citrus shoots. These behavioral results indicate that a mechanism for the success of guava intercropping for sustainable, ecological disease management may be the indirect effect of guava on citrus attractiveness. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Vitor C Pacheco da Silva
Full Text Available Mealybugs (Hemiptera: Pseudococcidae are pests constraining the international trade of Brazilian table grapes. They damage grapes by transmitting viruses and toxins, causing defoliation, chlorosis, and vigor losses and favoring the development of sooty mold. Difficulties in mealybug identification remain an obstacle to the adequate management of these pests. In this study, our primary aim was to identify the principal mealybug species infesting the major table grape-producing regions in Brazil, by morphological and molecular characterization. Our secondary aim was to develop a rapid identification kit based on species-specific Polymerase Chain Reactions, to facilitate the routine identification of the most common pest species. We surveyed 40 sites infested with mealybugs and identified 17 species: Dysmicoccus brevipes (Cockerell, Dysmicoccus sylvarum Williams and Granara de Willink, Dysmicoccus texensis (Tinsley, Ferrisia cristinae Kaydan and Gullan, Ferrisia meridionalis Williams, Ferrisia terani Williams and Granara de Willink, Phenacoccus baccharidis Williams, Phenacoccus parvus Morrison, Phenacoccus solenopsis Tinsley, Planococcus citri (Risso, Pseudococcus viburni (Signoret, Pseudococcus cryptus Hempel, four taxa closely related each of to Pseudococcus viburni, Pseudococcus sociabilis Hambleton, Pseudococcus maritimus (Ehrhorn and Pseudococcus meridionalis Prado, and one specimen from the genus Pseudococcus Westwood. The PCR method developed effectively identified five mealybug species of economic interest on grape in Brazil: D. brevipes, Pl. citri, Ps. viburni, Ph. solenopsis and Planococcus ficus (Signoret. Nevertheless, it is not possible to assure that this procedure is reliable for taxa that have not been sampled already and might be very closely related to the target species.
Jiu, Min; Hu, Jian; Wang, Lun-Ji; Dong, Jun-Feng; Song, Yue-Qin; Sun, Hui-Zhong
Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a cryptic species complex, causing significant crop losses in China during the last decade. Although knowledge of cryptic species composition and dynamics within B. tabaci complex is critical for developing sustainable pest management strategies, limited information is available on this pest in the Henan province of China. A systematic survey of the cryptic species composition and distribution of B. tabaci complex in different locations of Henan province was conducted in 2012. The results of RAPD-PCR and the gene for the mitochondrial cytochrome oxidase subunit-1 (mtCOI) based phylogenetic relationships established using Bayesian method indicated there were four known cryptic species MEAM1, MED, Asia II 3, Asia II 9 and a new cryptic species named China 6 in Henan province. In the survey, the invasive cryptic species MED and MEAM1 were found to be predominant with wide spread distribution across the surveyed regions. On the contrary, the indigenous B. tabaci cryptic species including Asia II 3, Asia II 9 and China 6 remained with low prevalence in some surveyed regions. Cryptic species MEAM1 and MED have not completely displaced the native B. tabaci in Henan province. This current study for the first time unifies our knowledge of the diversity and distribution of B. tabaci across Henan province of China. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.
Full Text Available Pentalonia nigronervosa Coquerel (Hemiptera: Aphididae is the only known vector of Banana bunchy top virus (BBTV. The objective of this research was to study the preference and suitability of banana aphid P. nigronervosa to various banana genotypes. Survey conducted at Talang Betutu, South Sumatra indicates the existence of different preferences of the P. nigronervosa toward different varieties in the field. Host suitability test was conducted using 13 banana varieties that were invested with P. nigronervosa from taro plants. Preference test was conducted using a 200 cm x 200 cm x 150 cm mesh cage that were used to house 13 banana genotypes that were invested with P. nigronerosa. The numbers of aphids on different banana genotypes were observed. Result of the study showed that “kepok” genotype was more suitable for the growth of P. nigronervosa compared to other genotypes. The suitability was shown by higher population, faster population growth, lower mortality and the higher proportion of alate adults. Banana kepok infested with 20 aphids at the beginning of the test reached 324 individuals within 24 days with population growth rate of 8.27% per day, and produced 1.9% of alate imagoes appeared 6 days after infestation. Host preference test using the same genotypes suggested that the aphid prefer banana kepok more than to any other genotypes.
Faraone, Nicoletta; Hillier, N Kirk; Cutler, G Christopher
Plant-derived products can play an important role in pest management programs. Essential oils from Lavandula angustifolia (lavender) and Thymus vulgaris (thyme) and their main constituents, linalool and thymol, respectively, were evaluated for insecticidal activity and synergistic action in combination with insecticides against green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae). The essential oils and their main constituents exerted similar insecticidal activity when aphids were exposed by direct sprays, but were non-toxic by exposure to treated leaf discs. In synergism experiments, the toxicity of imidacloprid was synergized 16- to 20-fold by L. angustifolia and T. vulgaris essential oils, but far less synergism occurred with linalool and thymol, indicating that secondary constituents of the oils were probably responsible for the observed synergism. In contrast to results with imidacloprid, the insecticidal activity of spirotetramat was antagonized by L. angustifolia and T. vulgaris essential oils, and linalool and thymol. Our results demonstrate the potential of plant essential oils as synergists of insecticides, but show that antagonistic action against certain insecticides may occur.
Leptocorisa oratorius (Fabricius) (Hemiptera: Alydidae) is a major rice pest which feeds on the sap of stems and rice seeds. Some graminaceous weed species serve as an alternative host of L. oratorius causing outbreaks throughout the rice growing season. Population changes of L. oratorius during both rice growing seasons - wet-season rice and dry-season rice - including the influence of alternative host, barnyard grass Echinochloa crus-galli (Graminaceae) on the development of L. oratorius was studied. Results presented that L. oratorius was the dominant pest species during the late phase of rice growth. Adults of L. oratorius started their migrations to wet-season rice at the vegetative stage of rice growth, while they migrated to dry-season rice at the repropuctive stage of rice growth. Leptocorisa oratorius breds rapidly in rice fields. Meanwhile, other adults migrated to the rice field. The population of adults and nymphs significantly increased from the reproductive stage to grain formation and ripening stage in both rice growing seasons. The population of nymphs was greater than adults but not significantly different in their number of individuals. Leptocorisa oratorius had one generation in each rice growing season. The results of the host plant study indicated that L oratorius developed completely in barnyard grass E. crus-galli as well as rice Oriza sativa (Graminaceae). However, L. oratorius preferred rice to barnyard grass for feeding and oviposition.
Faraone, Nicoletta; Hillier, N. Kirk; Cutler, G. Christopher
Plant-derived products can play an important role in pest management programs. Essential oils from Lavandula angustifolia (lavender) and Thymus vulgaris (thyme) and their main constituents, linalool and thymol, respectively, were evaluated for insecticidal activity and synergistic action in combination with insecticides against green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae). The essential oils and their main constituents exerted similar insecticidal activity when aphids were exposed by direct sprays, but were non-toxic by exposure to treated leaf discs. In synergism experiments, the toxicity of imidacloprid was synergized 16- to 20-fold by L. angustifolia and T. vulgaris essential oils, but far less synergism occurred with linalool and thymol, indicating that secondary constituents of the oils were probably responsible for the observed synergism. In contrast to results with imidacloprid, the insecticidal activity of spirotetramat was antagonized by L. angustifolia and T. vulgaris essential oils, and linalool and thymol. Our results demonstrate the potential of plant essential oils as synergists of insecticides, but show that antagonistic action against certain insecticides may occur. PMID:26010088
Full Text Available UV-B induced changes in plants can influence sap-feeding insects through mechanisms that have not been studied. Herein the grain aphid, Sitobion avenae (Fabricius (Hemiptera: Aphididae, was monitored on barley plants under the treatments of control [0 kJ/ (m2.d], ambient UV-B [60 kJ/ (m2.d], and enhanced UV-B [120 kJ/ (m2.d] irradiation. Electrical penetration graph (EPG techniques were used to record aphid probing behaviors. Enhanced UV-B irradiated plants negatively affected probing behaviors of S. avenae compared with control plants. In particular, phloem factors that could diminish sieve element acceptance appeared to be involved, as reflected by smaller number of phloem phase, shorter phloem ingestion, and fewer aphids reaching the sustained phloem ingestion phase (E2>10min. On the other hand, factors from leaf surface, epidermis, and mesophyll cannot be excluded, as reflected by higher number of non-probing, longer non-probing and pathway phase, and later the time to first probe.
Full Text Available Lately in horticultural agroecosystems from Romania joined several insect species autochthonous. Among these is a species of bugs known as southern green stink bugs or Nezara viridula L. (Insecta: Hemiptera: Pentatomidae. Unlike other new entrants this bug species has a diversified polifagism being present in many plants but obvious damage produce only tomato fruit. The causes are unknown. Can be found in gardens, green spaces and parks. Often is observed in vegetable gardens where populations comprise all stages (egg, larva/nymph, adult. Although it has African origins of a warm area is interesting installation and survival in temperate zones like those in Europe. Presence in Europe appears to be more random which excludes primarily spread through the neighborhood. By observations made in west of Romania, during 2010-2015 we wanted to watch the evolution of the insect from the first point of occurrence (Timișoara, 2010. Also, were monitored tomato crops and ornamentals in gardens and green spaces from 5 counties. Only in four monitored counties it was observed this species. Most adults and larvae were registered in Timis county (5-6 adults or 7-8 larvae/tomato plant and 10 -11 adults or 15-20 larvae/ornamental shrub. In our country the insect has proven to be capable of a rapid spread in a relatively short time interval including surrounding counties.
Rakitov, Roman; Gorb, Stanislav N
Leafhoppers (Insecta, Hemiptera, Cicadellidae) actively coat their integuments with brochosomes, hollow proteinaceous spheres of usually 200-700 nm in diameter, with honeycombed walls. The coats have been previously suggested to act as a water-repellent and anti-adhesive protective barrier against the insect's own exudates. We estimated their wettability through contact angle (CA) measurements of water, diiodomethane, ethylene glycol and ethanol on detached wings of the leafhoppers Alnetoidia alneti, Athysanus argentarius and Cicadella viridis. Intact brochosome-coated integuments were repellent to all test liquids, except ethanol, and exhibited superhydrophobicity, with the average water CAs of 165-172°, and the apparent surface free energy (SFE) estimates not exceeding 0.74 mN m(-1). By contrast, the integuments from which brochosomes were removed with a peeling technique using fluid polyvinylsiloxane displayed water CAs of only 103-129° and SFEs above 20 mN m(-1). Observations of water-sprayed wings in a cryo-scanning electron microscope confirmed that brochosomal coats prevented water from contacting the integument. Their superhydrophobic properties appear to result from fractal roughness, which dramatically reduces the area of contact with high-surface-tension liquids, including, presumably, leafhopper exudates.
Full Text Available Plant-derived products can play an important role in pest management programs. Essential oils from Lavandula angustifolia (lavender and Thymus vulgaris (thyme and their main constituents, linalool and thymol, respectively, were evaluated for insecticidal activity and synergistic action in combination with insecticides against green peach aphid, Myzus persicae (Sulzer (Hemiptera: Aphididae. The essential oils and their main constituents exerted similar insecticidal activity when aphids were exposed by direct sprays, but were non-toxic by exposure to treated leaf discs. In synergism experiments, the toxicity of imidacloprid was synergized 16- to 20-fold by L. angustifolia and T. vulgaris essential oils, but far less synergism occurred with linalool and thymol, indicating that secondary constituents of the oils were probably responsible for the observed synergism. In contrast to results with imidacloprid, the insecticidal activity of spirotetramat was antagonized by L. angustifolia and T. vulgaris essential oils, and linalool and thymol. Our results demonstrate the potential of plant essential oils as synergists of insecticides, but show that antagonistic action against certain insecticides may occur.
Full Text Available Aonidia lauri (Bouche (Hemiptera: Diaspididae is a serious pest of laurel (Laurus nobilis L. in urban parts of the City of Podgorica (Montenegro. Severe infestation causes chlorotic spots and necrotic rings around feeding spots, drying and dieback of leaves and buds. In addition, plants become physiologically weak and lose in aesthetic quality, while continuous infestation in urban areas often leads to partial or complete drying of plants. This study of the biology of A. lauri on L. nobilis was carried out at three locations in Podgorica ('Stara Varoš', 'Centar' and 'Preko Morače', Montenegro, in 2010 and 2011. A. lauri developed three generations annually and overwintered on laurel leaves and branches as the second-instar nymph-larval stage. An extended period of larval development ensures a continuous presence of all development stages on plants, which leads to overlapping of generations. Sporadic predatory ladybirds, Chilocorus bipustulatus (L. (Coleoptera: Coccinellidae, whose larvae and adults feed on scales, were detected inside A. lauri colonies.
Albino M. Sakakibara
Full Text Available The genus Lycoderides Sakakibara, stat. nov. , its composition and descriptions of new species (Hemiptera, Membracidae, Stegaspidinae.The subgenus Lycoderes (Lycoderides Sakakibara, 1972 is raised to the genus category - Lycoderides stat. nov.. - : and it now includes: Lycoderides amazonicus (Sakakibara, 1991, comb. nov. , Lycoderides brevilobus (Sakakibara, 1972, comb. nov. , Lycoderides burmeisteri (Fairmaire, 1846, comb. nov. , Lycoderides cultratus (Sakakibara, 1991, comb. nov. , Lycoderides fernandezi (Strümpel, 1988, comb. nov. , Lycoderides fuscus (Amyot & Serville, 1843, comb. nov. , Lycoderides gradatus (Sakakibara, 1972, comb. nov. , Lycoderides hippocampus (Fabricius, 1803, comb. nov. , Lycoderides luteus (Funkhouser, 1940, comb. nov. , Lycoderides marginalis (Walker, 1851, comb. nov. , Lycoderides nathanieli (Cryan, 1999, comb. nov. , Lycoderides obtusus (Sakakibara, 1991, comb. nov. , Lycoderides pennyi (Sakakibara, 1991, comb. nov. , Lycoderides phasianus (Fowler, 1896, comb. nov. (= Enchenopa minamen Buckton, 1901,SYN. NOV: , Lycoderides protensus (Sakakibara, 1991, comb. nov. , Lycoderides serraticornis (Fowler, 1896, comb. nov. , and Lycoderides strumpeli (Sakakibara, 1991, comb. nov. The following new species are described: Lycoderides abditus, sp. nov. , Lycoderides brulei,SP. NOV. (: both from French Guiana, Lycoderides capixaba, sp. nov. (from Brazil, Espírito Santo, Lycoderides cavichiolii, sp. nov. (from Brazil, Rio de Janeiro, Lycoderides meloi, sp. nov. (from Brazil, Bahia, and Lycoderides oliviae, sp. nov. (from Brazil, Minas Gerais. Other nomenclatural change: Stegaspis bracteata (Fabricius, 1787 = Lycoderes capitata Buckton, 1903, syn. nov. New records of geographical distribution and a key to the species are provided.
Lashkari, Mohammadreza; Hentz, Matthew G; Boykin, Laura M
The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vector of citrus greening disease pathogen, Huanglongbing (HLB), is considered the most serious pest of citrus in the world. Prior molecular based studies have hypothesized a link between the D. citri in Iran and the USA (Florida). The purpose of this study was to collect morphometric data from D. citri populations from Iran (mtCOI haplotype-1), Florida (mtCOI haplotype-1), and Pakistan (mtCOI haplotype-6), to determine whether different mtCOI haplotypes have a relationship to a specific morphometric variation. 240 samples from 6 ACP populations (Iran-Jiroft, Chabahar; Florida-Ft. Pierce, Palm Beach Gardens, Port St. Lucie; and Pakistan-Punjab) were collected for comparison. Measurements of 20 morphological characters were selected, measured and analysed using ANOVA and MANOVA. The results indicate differences among the 6 ACP populations (Wilks' lambda = 0.0376, F = 7.29, P analysis showed that the Iran and Florida populations are distinct from each other but separate from the Pakistan population. Thus, three subgroups can be morphologically discriminated within D. citri species in this study, (1) Iran, (2) USA (Florida) and (3) Pakistan population. Morphometric comparisons provided further resolution to the mtCOI haplotypes and distinguished the Florida and Iranian populations.
Full Text Available The Asian citrus psyllid (ACP, Diaphorina citri Kuwayama (Hemiptera: Liviidae, vector of citrus greening disease pathogen, Huanglongbing (HLB, is considered the most serious pest of citrus in the world. Prior molecular based studies have hypothesized a link between the D. citri in Iran and the USA (Florida. The purpose of this study was to collect morphometric data from D. citri populations from Iran (mtCOI haplotype-1, Florida (mtCOI haplotype-1, and Pakistan (mtCOI haplotype-6, to determine whether different mtCOI haplotypes have a relationship to a specific morphometric variation. 240 samples from 6 ACP populations (Iran—Jiroft, Chabahar; Florida—Ft. Pierce, Palm Beach Gardens, Port St. Lucie; and Pakistan—Punjab were collected for comparison. Measurements of 20 morphological characters were selected, measured and analysed using ANOVA and MANOVA. The results indicate differences among the 6 ACP populations (Wilks’ lambda = 0.0376, F = 7.29, P < 0.0001. The body length (BL, circumanal ring length (CL, antenna length (AL, forewing length (WL and Rs vein length of forewing (RL were the most important characters separating the populations. The cluster analysis showed that the Iran and Florida populations are distinct from each other but separate from the Pakistan population. Thus, three subgroups can be morphologically discriminated within D. citri species in this study, (1 Iran, (2 USA (Florida and (3 Pakistan population. Morphometric comparisons provided further resolution to the mtCOI haplotypes and distinguished the Florida and Iranian populations.
Grout, Tim G; Stoltz, Kim C
South African fruit is sometimes rejected for export for the presence of live arthropods that are not considered pests of the fruit concerned. Macchiademus diplopterus (Distant) (Hemiptera: Lygaeidae) is a cereal pest but may aestivate on fruit of some tree crops in the Western Cape province of South Africa and occasionally results in rejections of export fruit. Ethyl formate in the form of the commercial product Vapormate (a patented combination of ethyl formate and carbon dioxide) was evaluated as a fumigant against M. diplopterus at a dosage of Vapormate 250 g/m3 or ethyl formate 1.29% and carbon dioxide 10.76% (both by volume) and when applied for 4 h gave complete control. Confirmatory trials with >35,000 M. diplopterus using the same treatment, resulted in no survivors. The arboreal mite Siculobata sicula (Berlese) (Sarcoptiformes: Oribatulidae) at times reaches high numbers on citrus in orchards if few pesticides are used and may result in export rejections. A small-scale trial using the same ethyl formate treatment also killed these mites. This treatment-time combination did not appear to have phytotoxic effects on pears or oranges, unless they had prior mechanical injuries that were accentuated. Ethyl formate therefore holds promise for disinfesting fruit before it is packed. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Khalifa M. Al-Kindi
Full Text Available In order to understand the distribution and prevalence of Ommatissus lybicus (Hemiptera: Tropiduchidae as well as analyse their current biographical patterns and predict their future spread, comprehensive and detailed information on the environmental, climatic, and agricultural practices are essential. The spatial analytical techniques such as Remote Sensing and Spatial Statistics Tools, can help detect and model spatial links and correlations between the presence, absence and density of O. lybicus in response to climatic, environmental, and human factors. The main objective of this paper is to review remote sensing and relevant analytical techniques that can be applied in mapping and modelling the habitat and population density of O. lybicus. An exhaustive search of related literature revealed that there are very limited studies linking location-based infestation levels of pests like the O. lybicus with climatic, environmental, and human practice related variables. This review also highlights the accumulated knowledge and addresses the gaps in this area of research. Furthermore, it makes recommendations for future studies, and gives suggestions on monitoring and surveillance methods in designing both local and regional level integrated pest management strategies of palm tree and other affected cultivated crops.
Olson, Dawn M; Prescott, Kristina R; Zeilinger, Adam R; Hou, Suqin; Coffin, Alisa W; Smith, Coby M; Ruberson, John R; Andow, David A
Landscape factors can significantly influence arthropod populations. The economically important brown stink bug, Euschistus servus (Say) (Hemiptera: Pentatomidae), is a native mobile, polyphagous and multivoltine pest of many crops in southeastern United States and understanding the relative influence of local and landscape factors on their reproduction may facilitate population management. Finite rate of population increase (λ) was estimated in four major crop hosts-maize, peanut, cotton, and soybean-over 3 yr in 16 landscapes of southern Georgia. A geographic information system (GIS) was used to characterize the surrounding landscape structure. LASSO regression was used to identify the subset of local and landscape characteristics and predator densities that account for variation in λ. The percentage area of maize, peanut and woodland and pasture in the landscape and the connectivity of cropland had no influence on E. servus λ. The best model for explaining variation in λ included only four predictor variables: whether or not the sampled field was a soybean field, mean natural enemy density in the field, percentage area of cotton in the landscape and the percentage area of soybean in the landscape. Soybean was the single most important variable for determining E. servus λ, with much greater reproduction in soybean fields than in other crop species. Penalized regression and post-selection inference provide conservative estimates of the landscape-scale determinants of E. servus reproduction and indicate that a relatively simple set of in-field and landscape variables influences reproduction in this species.
Almeida, Fabio Souto; Goncalves, Lenicio
Dysdercus maurus Distant, 1901 (Hemiptera, Pyrrhocoridae) is an important pest on Gossypium spp. (cotton tree), Citrus sinensis Osbeck (Rutaceae) and Citrus reticulata Blanco (Rutaceae) crops. This insect also feeds on seeds of Chorisia speciosa St. Hil. (Bombacaceae). This work aimed to evaluate the effects of temperature and food on the development of D. maurus. Eight treatments were carried out, in six of them bugs were fed with seeds of C. speciosa and kept at 15, 18, 20, 25 and 30 ± 1 deg C, 80 ± 3% RH and 12h photo phase or in laboratory conditions (23.5 ± 2.6 deg C, 73.3 ± 9.9 % RH), and in the other two treatments bugs were fed with seeds of cotton variety IAC-22 and kept at 25 or 30 deg C. In all treatments five immature stages were observed. The increase of temperature caused reduction in the developmental time. The temperature of 15 deg C disabled nymphal eclosion and was also lethal to those nymphs ecloded at other temperatures. The lower mortality of nymphs occurred in the temperature of 25 deg C with cotton as food (24.07%). The lower threshold temperature (Tb) occurred for the first instar (11.54 deg C) and the higher for the second instar (15.33 deg C). The females of D. maurus required more degree-days (329.93 degree-days) than males (300.49 degree-days) until adult emergence. (author)
Full Text Available The world’s only member of Hemiptera Auchenorrhyncha known to form true galls, the leafhopper Scenergates viridis (Vilbaste (Cicadellidae, transforms leaves of camelthorn (Alhagi maurorum Medikus, Fabaceae into pod-like chambers, up to 35 mm long, inside which individual leafhoppers develop, mate, and lay eggs. At the study site 40 km SE of Bukhara (Uzbekistan, two generations develop annually. First-instar nymphs cause young leaves to fold along the midrib. The subsequent development takes place inside the tightly closed growing gall, plugged at both ends with a mixture of leafhopper excrement, brochosomes, and crushed exuviae. These plugs act as mechanical barriers and sticky traps for intruders. The inner surface of the gall, lined with brochosomes and wax platelets, is hydrophobic. Adult males emerge from their galls and squeeze into female galls. Fertilized females insert an average of 146 eggs under the gall’s inner epidermis and remain inside, possibly protecting the brood, until they die. The walls of the galls containing eggs are approximately three times thicker than regular leaves. The galls are subject to predation by Gelechiidae caterpillars; the eggs of the leafhopper are parasitized by two species of Trichogrammatidae and one Mymaridae (Hymenoptera, and its larvae by one species of Pipunculidae (Diptera.
Full Text Available Polygalacturonase (PG is an enzyme in the salivary glands of piercing-sucking mirid bugs (Hemiptera: Miridae that plays a key role in plant feeding and injury. By constructing a full-length cDNA library, we cloned and characterized 14 PG genes from the salivary glands of Apolygus lucorum, a pestiferous mirid bug in cotton, fruit trees and other crops in China. BLAST search analysis showed that the amino acid sequences deduced from transcripts of the PG genes were closely related to PGs from other mirid bugs. Phylogenetic analysis showed that the PGs of mirid bugs had six main branches, PG1-PG6 (Genbank accession numbers: KF881899~KF881912. We investigated the mRNA expression patterns of the A. lucorum PG genes using real-time PCR. All 14 PGs were expressed significantly higher in the salivary glands than in other tissues (head, thorax, abdomen, leg and wing. For eggs and nymphs, the expression levels of these PGs were much higher in the 5th instar stage than in the egg, and 1st and 3rd instar stages. The PG expression levels in 1-day-old adults were very low, and increased in 5, 20 and 30-day-old adults. Additionally, PG expression levels were generally similar between males and females. The possible physiological functions of PGs in A. lucorum were discussed.
Gomez-Polo, Priscila; Alomar, Oscar; Castañé, Cristina; Aznar-Fernández, Thaïs; Lundgren, Jonathan G; Piñol, Josep; Agustí, Nuria
The aphid Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) and the thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) are common pests in Mediterranean lettuce crops, where Orius spp. are common generalist predators. Predation by Orius spp. was studied in a lettuce plot by conventional polymerase chain reaction (PCR) and real-time PCR analyses using specific primers of both main pests. Also, high-throughput sequencing was used to have a wider approach of the diet of these predators in natural field conditions. Molecular analyses indicated a higher predation on N. ribisnigri in spring and on F. occidentalis in summer. Predation on alternative prey, like Collembola, was also found in both seasons. Real-time PCR was more sensitive than conventional PCR in showing the target trophic links, whereas high-throughput sequencing revealed predation on other natural enemies - intraguild predation (IGP), showing other trophic interactions of Orius majusculus within the studied ecosystem. This study gives important information about the trophic relationships present in Mediterranean lettuce crops in different periods of the year. The detected predation by Orius spp. on alternative prey, as well as on other natural enemies, should be further investigated to clarify whether it adds or detracts to the biological control of N. ribisnigri and F. occidentalis. © 2015 Society of Chemical Industry.
Gossner, Martin M.; Simons, Nadja K.; Achtziger, Roland; Blick, Theo; Dorow, Wolfgang H. O.; Dziock, Frank; Köhler, Frank; Rabitsch, Wolfgang; Weisser, Wolfgang W.
Analyses of species traits have increased our understanding of how environmental drivers such as disturbances affect the composition of arthropod communities and related processes. There are, however, few studies on which traits in the arthropod community are affected by environmental changes and which traits affect ecosystem functioning. The assembly of arthropod traits of several taxa is difficult because of the large number of species, limited availability of trait databases and differences in available traits. We sampled arthropod species data from a total of 150 managed grassland plots in three regions of Germany. These plots represent the spectrum from extensively used pastures to mown pastures to intensively managed and fertilized meadows. In this paper, we summarize information on body size, dispersal ability, feeding guild and specialization (within herbivores), feeding mode, feeding tissue (within herbivorous suckers), plant part (within herbivorous chewers), endophagous lifestyle (within herbivores), and vertical stratum use for 1,230 species of Coleoptera, Hemiptera (Heteroptera, Auchenorrhyncha), Orthoptera (Saltatoria: Ensifera, Caelifera), and Araneae, sampled by sweep-netting between 2008 and 2012. We compiled traits from various literature sources and complemented data from reliable internet sources and the authors’ experience.
Xi, Y; Pan, P-L; Ye, Y-X; Yu, B; Zhang, C-X
Chitin deacetylases (CDAs) are enzymes required for one of the pathways of chitin degradation, in which chitosan is produced by the deacetylation of chitin. Bioinformatic investigations with genomic and transcriptomic databases identified four genes encoding CDAs in Nilaparvata lugens (NlCDAs). Phylogenetic analysis showed that insect CDAs were clustered into five major groups. Group I, III and IV CDAs are found in all insect species, whereas the pupa-specific group II and gut-specific group V CDAs are not found in the plant-sap/blood-sucking hemimetabolous species from Hemiptera and Anoplura. The developmental and tissue-specific expression patterns of four NlCDAs revealed that NlCDA3 was a gut-specific CDA, with high expression at all developmental stages; NlCDA1, NlCDA2 and NlCDA4 were highly expressed in the integument and peaked periodically during every moulting, which suggests their roles in chitin turnover of the insect old cuticle. Lethal phenotypes of cuticle shedding failure and high mortality after the injection of double-stranded RNAs (dsRNAs) for NlCDA1, NlCDA2 and NlCDA4 provide further evidence for their functions associated with moulting. No observable morphological and internal structural abnormality was obtained in insects treated with dsRNA for gut-specific NlCDA3. © 2014 The Royal Entomological Society.
Booth, Warren; Saenz, Virna L; Santangelo, Richard G; Wang, Changlu; Schal, Coby; Vargo, Edward L
The bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), has experienced an extraordinary global resurgence in recent years, the reasons for which remain poorly understood. Once considered a pest of lower socioeconomic classes, bed bugs are now found extensively across all residential settings, with widespread infestations established in multiapartment buildings. Within such buildings, understanding the population genetic structure and patterns of dispersal may prove critical to the development of effective control strategies. Here, we describe the development of 24 high-resolution microsatellite markers through next generation 454 pyrosequencing and their application to elucidate infestation dynamics within three multistory apartment buildings in the United States. Results reveal contrasting characteristics potentially representative of geographic or locale differences. In Raleigh, NC, an infestation within an apartment building seemed to have started from a single introduction followed by extensive spread. In Jersey City, NJ, two or more introductions followed by spread are evident in two buildings. Populations within single apartments in all buildings were characterized by high levels of relatedness and low levels of diversity, indicative of foundation from small, genetically depauperate propagules. Regardless of the number of unique introductions, genetic data indicate that spread within buildings is extensive, supporting both active and human-mediated dispersal within and between adjacent rooms or apartments spanning multiple floors.
Estados de desarrollo y biología de tres especies de Lygaeinae (Hemiptera-Heteroptera: Lygaeoidea: Lygaeidae Life stages and biology of three species of Lygaeinae (Hemiptera-Heteroptera: Lygaeoidea: Lygaeidae
Full Text Available Se describen los estados de desarrollo (huevo, ninfas y adulto de 3 especies de Lygaeinae (Hemiptera-Heteroptera: Lygaeoidea: Lygaeidae, Anochrostomus formosus (Blanchard principalmente asociada con especies de Asteraceae y Convolvulaceae, y Lygaeus reclivatus reclivatus(Say y Oncopeltus (Oncopeltus sexmaculatus (Stål asociadas con Asclepiadaceae. Las descripciones están basadas en ejemplares colectados en los estados de Oaxaca y Guerrero (México y criados en el laboratorio. Se ilustra cada uno de los estadios y se incluyen notas acerca de su biología y plantas huéspedes.The life stages (egg, nymphs, and adult of 3 species of Lygaeinae (Hemiptera-Heteroptera: Lygaeoidea: Lygaeidae are described. Anochrostomus formosus (Blanchard is mainly associated with species of Asteraceae and Convolvulaceae, whereas Lygaeus reclivatus reclivatus (Say and Oncopeltus (Oncopeltus sexmaculatus (Stål are associated with Asclepiadaceae. Descriptions are based on individuals collected in the states of Oaxaca and Guerrero (Mexico, and reared in laboratory. Illustrations of each instar are also included, as well as notes about their biology and host plants.
Martin D. Oliveira
Full Text Available Population growth and within-plant distribution of the striped mealybug Ferrisia virgata (Cockerell (Hemiptera, Pseudococcidae on cotton. The striped mealybug, Ferrisia virgata (Cockerell (Hemiptera, Pseudococcidae, is a widely distributed and polyphagous pest species, which naturally occurs on cotton plants in Brazil. This study evaluated the establishment and population growth as well as the within-plant distribution of F. virgata on four cotton cultivars: CNPA 7H (white fibers, BRS Verde, BRS Safira, and BRS Rubi (colored fibers. The experiment was conducted in a complete randomized design with four treatments (cultivars and 18 replications of each. Thus, cotton plants of each cultivar were infested with 100 newly hatched nymphs of F. virgata. The number of adult female mealybugs and the total number of mealybugs per plant were quantified, respectively, at 25 and 50 days after infestation. The developmental and pre-reproductive periods were also determined. Furthermore, we verified the distribution of F. virgata on the plant parts at 25 and 50 days after infestation. Ferrisia virgata showed similar growth of 412-fold in the four cotton cultivars studied. Also, the nymphs were spread on infested leaves; the secondgeneration nymphs were spread and established in all plant parts. Our results characterize F. virgata as having much potential as an important cotton pest in Brazil.
Barbosa, Paulo R R; Michaud, J P; Bain, Clint L; Torres, Jorge B
Recent widespread infestations of the invasive sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), in sorghum fields in the southern USA have created demand for insecticides that will provide effective control of sugarcane aphid, while conserving those beneficial species that contribute to biological control of the pest. We tested the susceptibility of both adult and immature stages of two aphid predators, the green lacewing, Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae), and the insidious flower bug, Orius insidiosus (Say) (Hemiptera: Anthocoridae), to three aphicides, flonicamid, sulfoxaflor and flupyradifurone. Flonicamid was innocuous to both species regardless of life stage or route of exposure. Lacewing adults were more susceptible to sulfoxaflor and flupyradifurone than were larvae, and had higher mortality when fed contaminated honey solution than when contacting residues on an inert surface. When laid in sunflower stems treated with these two materials, eggs of O. insidiosus hatched successfully, but nymphs experienced significant mortality when exposed to treated stems, likely due to phytophagous behavior that resulted in some insecticide ingestion. Despite these impacts, we conclude that both sulfoxaflor and flupyradifurone are likely to be relatively innocuous in comparison to more broad-spectrum insecticides and are thus potentially compatible with biological control and overall management of M. sacchari in grain sorghum.
Caballero, Alejandro; Ramos-Portilla, Andrea Amalia; Kondo, Takumasa
Herein we describe a new species, Tillancoccus koreguajae Caballero & Ramos, sp. n. (Hemiptera: Coccidae) from Colombia collected on sugarcane. Pinnaspis strachani (Cooley) is also recorded on sugarcane for the first time worldwide. An updated list of seven species of Coccomorpha on sugarcane in Colombia is provided, including information on its distribution, biology, and mutualistic ants for each species. Seven species of scale insects (Hemiptera: Coccomorpha) have been recorded previously on sugarcane, Saccharum officinarum L. (Poaceae) in Colombia: Pseudococcidae: Dysmicoccus boninsis (Kuwana), D. brevipes (Cockerell), Pseudococcus calceolariae (Maskell), Saccharicoccus sacchari (Cockerell); Coccidae: Pulvinaria elongata Newstead; Diaspididae: Duplachionaspis divergens (Green) and Serenaspis minima (Maskell). However, the record of S. minima in Colombia is considered doubtful as there are no voucher specimens from Colombia and because the distribution of this species is currently limited to the Australasian region. Pseudococcus calceolariae is present in Colombia but its record on sugarcane is also doubtful. A taxonomic key for the identification of scale insects on sugarcane in Colombia is provided.
Sobre o condicionamento alimentar na cochonilha-branca, Planococcus citri (Risso (Hemiptera: pseudococcidae Regarding to host conditioning in citrus mealybug Planococcus citri (Risso (Hemiptera: pseudococcidae
Lenira Viana Costa Santa-Cecília
Full Text Available Estudos do comportamento alimentar mediante a técnica de "Electrical Penetration Graphs" (EPG das cochonilhas-farinhentas (Pseudococcidae provenientes de um hospedeiro de criação alternativo têm mostrado que esses insetos não atingem ou demoram cerca de 9 horas para alcançar a fase floemática. Por outro lado, aqueles provenientes do hospedeiro-fonte atingem a fase floemática mais rapidamente e apresentam maior frequência de alimentação nos vasos crivados. Esses resultados indicam a presença do fenômeno de condicionamento alimentar, ainda não demonstrado em cochonilhas. Assim, o presente trabalho teve como objetivo determinar a existência desse fenômeno em Planococcus citri (Risso (Hemiptera: Pseudococcidae. Foram realizados testes de livre escolha, monitoramento eletrônico (EPG e estudos de alguns parâmetros biológicos. Em todos os experimentos, o cafeeiro (Coffea arabica L., os citros (Citrus sinensis L. e abóbora (Cucurbita maxima L. foram utilizados como substratos de criação (fonte da cochonilha, sendo os tratamentos constituídos pela combinação entre os hospedeiros-fonte e os hospedeiros receptores (café e citros. O teste de escolha entre cafeeiro e citros nas primeiras 72 horas mostrou que as cochonilhas criadas em cafeeiro apresentaram preferência pelo cafeeiro; aquelas originadas dos citros mostraram uma tendência, embora não significativa, em selecionar os citros em relação ao cafeeiro e aquelas criadas em abóbora não mostraram preferência por nenhum dos hospedeiros. Os estudos do comportamento alimentar mediante o monitoramento eletrônico (EPG mostraram que a fase floemática, considerada como a fase de aceitação do hospedeiro, foi mais frequente em cafeeiro, seja com cochonilhas oriundas deste substrato, seja de citros. Aqueles insetos mantidos em abóbora e transferidos para o cafeeiro ou citros apresentaram excepcionalmente ou não apresentaram nenhuma fase floemática, respectivamente. A
Full Text Available O percevejo-asa-preta-da-soja Edessa meditabunda (Fabricius (Hemiptera: Pentatomidae no final do ciclo da soja dispersa para algodoeiro e utiliza essa planta como hospedeiro alternativo. Visando conhecer o potencial desta espécie como praga em algodoais e auxiliar na tomada decisão quanto ao manejo deste inseto, hipotetizou-se nesse trabalho que o algodoeiro é nutricionalmente adequado para a reprodução e desenvolvimento de E. meditabunda. Os tratamentos testados foram: 1 folhas e maçã de algodoeiro e 2 dieta padrão, recomendada para criação de pentatomídeos fitófagos em laboratório, utilizada como testemunha. As características biológicas avaliadas foram: período de desenvolvimento ninfal, duração de cada ínstar, porcentagem de sobrevivência, peso dos adultos na emergência, longevidade de machos e de fêmeas, período de pré-oviposição e de oviposição, número total de ovos por fêmea e fecundidade das fêmeas. Observou-se que, apesar do prolongamento do período de desenvolvimento ninfal, as ninfas alimentadas com algodoeiro sobreviveram, atingiram a fase adulta e os adultos se reproduziram, o que nos permite sugerir que o algodoeiro seja uma planta nutricionalmente adequada para o desenvolvimento e reprodução de E. meditabunda, permitindo a manutenção do inseto em campo após a colheita da soja. RESUMO El chinche Edessa meditabunda (Fabricius (Hemiptera: Pentatomidae al final del ciclo de la soja emigra al cultivo de algodón y utiliza esta planta como un huésped alternativo. Con el objetivo de conocer el potencial de esta especie como una plaga en los algodonales y ayudar en la toma de decisiones con respecto al manejo de este insecto, se planteó la hipótesis en este estudio que el algodón y nutritiva, adecuada para la reproducción y el desarrollo de E. meditabunda. Los tratamientos fueron:1 las hojas y el fruto del algodón 2 dieta estándar recomendada para la cría de pentatomidos fitófagos en el
Costello, Michael J
This study looked at regulated deficit irrigation (RDI) on leafhoppers in the genus Erythroneura (Erythroneura elegantula Osborn, or western grape leafhopper, and Erythroneura variabilis Beamer) (Hemiptera: Cicadellidae), which are serious pests of cultivated grape (Vitis vinifera L.) in California. RDI is an irrigation strategy that reduces irrigation during a critical point in the phenology of a cultivated perennial crop, to improve vegetative balance and crop quality. Erythroneura spp. are known to respond negatively to vine water stress, and the second generation ofleafhoppers begins during a potential RDI initiation period, between berry set and veraison (beginning of fruit maturation). In experiments at commercial wine grape vineyards, I imposed deficits of between 25 and 50% of crop full evapotranspiration (ET(c)) between berry set and veraison, with control treatments based on the growers' standard irrigations (typically between 0.8 and 1.0 ET(c)), and then we counted leafhopper nymphs weekly, and leafhopper eggs after the second generation. Results show a consistent reduction of second generation nymphal density with this type of RDI, with average density approximately 50% lower under deficit treatments in all three studies. Deficit irrigation reduced second generation egg density by 54% at one site and by 29.9% at another. These results confirm previous studies regarding the sensitivity of Erythroneura spp. to grapevine water stress, and, in addition, they show that a season-wide irrigation deficit is not necessary for reduction in leafhopper density. Results suggest that lower oviposition at least partly explains the lower nymphal density in the deficit treatments.