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Sample records for reticulatum muller mollusca

  1. Antifeedant compounds from three species of Apiaceae active against the field slug, Deroceras reticulatum (Muller).

    Science.gov (United States)

    Birkett, Michael A; Dodds, Catherine J; Henderson, Ian F; Leake, Lucy D; Pickett, John A; Selby, Martin J; Watson, Peter

    2004-03-01

    Extracts of volatiles from foliage of three plants in the Apiaceae, Conium maculatum L. (hemlock), Coriandrum sativum L. (coriander), and Petroselinum crispum Mill. (Nym.) (parsley), previously shown to exhibit antifeedant activity in assays with the field slug, Deroceras reticulatum (Muller) (Limacidae: Pulmonata), were studied further to identify the active components. Coupled gas chromatography-mass spectrometry (GC-MS) and neurophysiological assays using tentacle nerve preparations resulted in the identification of 11 active compounds from the three extracts. Wheat flour feeding bioassays were used to determine which of these compounds had the highest antifeedant activity. One of the most active compounds was the alkaloid gamma-coniceine, from C. maculatum. The role of potentially toxic alkaloids as semiochemicals and the potential for using such compounds as crop protection agents to prevent slug feeding damage is discussed.

  2. Assessing metal contamination from construction and demolition (C&D) waste used to infill wetlands: using Deroceras reticulatum (Mollusca: Gastropoda).

    Science.gov (United States)

    Staunton, John A; Mc Donnell, Rory J; Gormally, Michael J; Williams, Chris D; Henry, Tiernan; Morrison, Liam

    2014-11-01

    Large quantities of construction and demolition waste (C&D) are produced globally every year, with little known about potential environmental impacts. In the present study, the slug, Deroceras reticulatum (Mollusca: Gastropoda) was used as the first biomonitor of metals (Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Ti, Tl, V and Zn) on wetlands post infilling with construction and demolition (C&D) waste. The bioaccumulation of As, Ba, Cd, Co, Sb, Se and Tl were found to be significantly elevated in slugs collected on C&D waste when compared to unimproved pastures (control sites), while Mo, Se and Sr had significantly higher concentrations in slugs collected on C&D waste when compared to known contaminated sites (mining locations), indicating the potential hazardous nature of C&D waste to biota. Identifying exact sources for these metals within the waste can be problematic, due to its heterogenic nature. Biomonitors are a useful tool for future monitoring and impact studies, facilitating policy makers and regulations in other countries regarding C&D waste infill. In addition, improving separation of C&D waste to allow increased reuse and recycling is likely to be effective in reducing the volume of waste being used as infill, subsequently decreasing potential metal contamination.

  3. In Memoriam Dr. J. Muller

    NARCIS (Netherlands)

    Kalkman, C.

    1984-01-01

    At the age of 61, Jan Muller died on 5 October 1983, after a very short illness which only some weeks earlier had been detected. His rapid decline but also his courage during the last few weeks, have made a deep impression on all who have witnessed them. Jan Muller was born on 15 October 1921 at

  4. Lifetime characteristics of Gaiger-Muller counters

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    Kartalović Nenad M.

    2016-01-01

    Full Text Available This paper discusses the process of functional aging of Geiger-Muller counters. Two types of Geiger-Muller counter chambers were characterized in an experiment using a combined constant voltage. Chamber A had a coaxial geometry and chamber B had a plan-parallel geometry. The experimental results indicate that the aging process was faster in the case of chambers with a coaxial geometry. The results are explained based on the process of electrical discharges in gasses.

  5. Playing Muller Games in a Hurry

    Directory of Open Access Journals (Sweden)

    John Fearnley

    2010-06-01

    Full Text Available This work studies the following question: can plays in a Muller game be stopped after a finite number of moves and a winner be declared. A criterion to do this is sound if Player 0 wins an infinite-duration Muller game if and only if she wins the finite-duration version. A sound criterion is presented that stops a play after at most 3^n moves, where n is the size of the arena. This improves the bound (n!+1^n obtained by McNaughton and the bound n!+1 derived from a reduction to parity games.

  6. Playing Muller Games in a Hurry

    OpenAIRE

    Fearnley, John; Zimmermann, Martin

    2010-01-01

    This work studies the following question: can plays in a Muller game be stopped after a finite number of moves and a winner be declared. A criterion to do this is sound if Player 0 wins an infinite-duration Muller game if and only if she wins the finite-duration version. A sound criterion is presented that stops a play after at most 3^n moves, where n is the size of the arena. This improves the bound (n!+1)^n obtained by McNaughton and the bound n!+1 derived from a reduction to parity games.

  7. Hermann Muller and Mutations in Drosophila

    Science.gov (United States)

    dropdown arrow Site Map A-Z Index Menu Synopsis Hermann Muller and Mutations in Drosophila Resources with University of Texas. In Austin his experiments on fruit flies (Drosophila) first showed that exposure to September to spend a year at the only Drosophila laboratory in Europe which was doing parallel work

  8. Neuropeptides predicted from the transcriptome analysis of the gray garden slug Deroceras reticulatum

    Science.gov (United States)

    The gray garden slug, Deroceras reticulatum (Gastropoda: Pulmonata), is one of the most common terrestrial molluscs. Studies on D. reticulatum have mainly focused on ecology and biology due to severe damages on a wide range of vegetables and field crops. However, little is known about hormonal signa...

  9. Rare beneficial mutations can halt Muller's ratchet

    Science.gov (United States)

    Balick, Daniel; Goyal, Sidhartha; Jerison, Elizabeth; Neher, Richard; Shraiman, Boris; Desai, Michael

    2012-02-01

    In viral, bacterial, and other asexual populations, the vast majority of non-neutral mutations are deleterious. This motivates the application of models without beneficial mutations. Here we show that the presence of surprisingly few compensatory mutations halts fitness decay in these models. Production of deleterious mutations is balanced by purifying selection, stabilizing the fitness distribution. However, stochastic vanishing of fitness classes can lead to slow fitness decay (i.e. Muller's ratchet). For weakly deleterious mutations, production overwhelms purification, rapidly decreasing population fitness. We show that when beneficial mutations are introduced, a stable steady state emerges in the form of a dynamic mutation-selection balance. We argue this state is generic for all mutation rates and population sizes, and is reached as an end state as genomes become saturated by either beneficial or deleterious mutations. Assuming all mutations have the same magnitude selective effect, we calculate the fraction of beneficial mutations necessary to maintain the dynamic balance. This may explain the unexpected maintenance of asexual genomes, as in mitochondria, in the presence of selection. This will affect in the statistics of genetic diversity in these populations.

  10. Physiological responses of cacharas Pseudoplatystoma reticulatum submitted to natural anesthetics

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    Milena Souza dos Santos Sanchez

    2014-02-01

    Full Text Available The present study the aimed to evaluate the induction time, recovery time and physiological responses of cacharas, Pseudoplatystoma reticulatum, submitted to eugenol and menthol. 42 cacharas were exposed to eugenol 100 mgL-1 (n=14 and menthol 150 mgL-1 (n=14 and the control group (n=14 which were not exposed to any anesthetics. At the time 0 and 24 hours after induction, the bloods of 7 fishes per treatment were collected to measure the hematologic parameters and plasma glucose evaluation. The recovery was conducted in aquariums free of anesthetic, and induction and recovery times were monitored. The results were submitted to analysis of variance (P0.05 for induction time, however the recovery time had a significant reduction (P<0.05 for the menthol 150 mgL-1. There was no treatment effects on hematologic parameters, except for mean corpuscular volume (VCM, which was observed an interaction effect between factors, once fish anesthetized with eugenol showed significant reduction (P<0.05 on VCM 24 hours after anesthesia. Plasma glucose values did not differ at 0 hour after induction. 24 hours after induction, both control group and fishes exposed to eugenol and menthol were significantly reduce in VCM. Eugenol at 100 mgL-1 and menthol at 150 mgL-1 may be safely induced in cachara during biometrics procedures.

  11. Bloom of the Yessotoxin producing dinoflagellate Protoceratium reticulatum (Dinophyceae) in Northern Chile

    Science.gov (United States)

    Álvarez, Gonzalo; Uribe, Eduardo; Díaz, Rosario; Braun, Mauricio; Mariño, Carmen; Blanco, Juan

    2011-05-01

    In summer 2007, a dinoflagellate preliminarily identified as Protoceratium reticulatum bloomed in Bahía Mejillones, northern Chile. Phytoplankton samples were analyzed in detail by light and scanning electron microscopy revealing the presence of resting cyst and motile cells of P. reticulatum. Oceanographic and phytoplankton data suggest that the bloom was initiated offshore by motile cells and germinated cysts during an upwelling pulse. These cells were advected into the bay when upwelling relaxed and grew without any relevant competitor. Phytoplankton net samples were found to contain yessotoxin as the only toxin in an estimated proportion of 0.2 and 0.4 pg cell - 1 , thus confirming that P. reticulatum is a source of yessotoxin in northern Chilean waters and consequently that it poses a risk for human health and mollusk exploitation in the area.

  12. Antioxidant, Cytotoxic, and Antiproliferative Activities and Total Polyphenol Contents of the Extracts of Geissospermum reticulatum Bark

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    Joanna J. Sajkowska-Kozielewicz

    2016-01-01

    Full Text Available Geissospermum species are medically important plants due to their health-promoting effects. The objective of this study was to determine the antioxidant ability and antiproliferative and cytotoxic effects of infusions, tinctures, and ethanolic extracts of Geissospermum reticulatum barks in relation to the contents of total phenolics and flavonoids. Seven samples of barks were collected in various regions of Peruvian Amazonia. We found that the amount of total phenolics in the studied products varied from 212.40 ± 0.69 to 1253.92 ± 11.20 mg GAE/kg. In our study there is a correlation (R2=0.7947 between the results of antioxidants assays: FRAP and ORAC for tinctures, infusions, and ethanolic extracts of G. reticulatum barks. We have also observed antiproliferative activities of the ethanolic extracts on normal T-cells. These extracts have caused death on malignant cell lines (THP-1 and HL-60 and this data correlates well with their antioxidant capacity measured by ORAC method. Interestingly, the highest concentration of the ethanolic extract was not toxic in the zebrafish embryo developmental assay. Our results indicate that G. reticulatum is rich in antioxidants and have cytotoxic and antiproliferative properties. The data suggests potential immunosuppressive role of the extracts. This is the first study presenting the results of chemical and biological analysis of multiple preparations from G. reticulatum.

  13. The complete mitochondrial genome of the gray garden slug Deroceras reticulatum (Gastropoda: Pulmonata: Stylommatophora)

    Science.gov (United States)

    The complete circular mitochondrial genome of D. reticulatum is 14,048 bp in length, consisting of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and 2 ribosomal RNA (rRNA) genes (GenBank accession number: KY765589). The overall base composition was 31.0 % A, 12.2 % C, 17.7 % G and 39...

  14. Influence des Parcs agro-forestiers à Piliostigma reticulatum sur l ...

    African Journals Online (AJOL)

    SARAH

    30 juin 2013 ... millet spikes. The number of larvae of Coniesta ignefusalis was counted. It appeared from these results that the density of flower-feeding insects in agroforestry systems obtained with P. reticulatum is small compared to the two controls. .... (respectivement 75 et 60 insectes) est presque le double de celui ...

  15. De weekdieren van de Nederlandse brakwatergebieden (Mollusca)

    NARCIS (Netherlands)

    Kuijper, W.J.

    2000-01-01

    The molluscs of the brackish waters in the Netherlands (Mollusca) The Netherlands is a river delta rich in brackish waters. The organisms in these waters need to be adapted to extreme conditions, especially large fluctuations in chlorinity. However, several species occur optimally in this habitat.

  16. Notes on Loricata (Mollusca) 11-14

    NARCIS (Netherlands)

    Kaas, P.

    1985-01-01

    Four new species of chitons (Mollusca, Polyplacophora) are described, viz Leptochiton (L.) dispersus and L. (L.) permodestus from Transkei, L. (L.) meiringae from the eastern Cape Province, S Africa (note 11) and Ischnochiton (Stenosemus) vanbellei from the Mediterranean Sea (note 14). New records

  17. Plastomes of the green algae Hydrodictyon reticulatum and Pediastrum duplex (Sphaeropleales, Chlorophyceae

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    Hilary A. McManus

    2017-05-01

    Full Text Available Background Comparative studies of chloroplast genomes (plastomes across the Chlorophyceae are revealing dynamic patterns of size variation, gene content, and genome rearrangements. Phylogenomic analyses are improving resolution of relationships, and uncovering novel lineages as new plastomes continue to be characterized. To gain further insight into the evolution of the chlorophyte plastome and increase the number of representative plastomes for the Sphaeropleales, this study presents two fully sequenced plastomes from the green algal family Hydrodictyaceae (Sphaeropleales, Chlorophyceae, one from Hydrodictyon reticulatum and the other from Pediastrum duplex. Methods Genomic DNA from Hydrodictyon reticulatum and Pediastrum duplex was subjected to Illumina paired-end sequencing and the complete plastomes were assembled for each. Plastome size and gene content were characterized and compared with other plastomes from the Sphaeropleales. Homology searches using BLASTX were used to characterize introns and open reading frames (orfs ≥ 300 bp. A phylogenetic analysis of gene order across the Sphaeropleales was performed. Results The plastome of Hydrodictyon reticulatum is 225,641 bp and Pediastrum duplex is 232,554 bp. The plastome structure and gene order of H. reticulatum and P. duplex are more similar to each other than to other members of the Sphaeropleales. Numerous unique open reading frames are found in both plastomes and the plastome of P. duplex contains putative viral protein genes, not found in other Sphaeropleales plastomes. Gene order analyses support the monophyly of the Hydrodictyaceae and their sister relationship to the Neochloridaceae. Discussion The complete plastomes of Hydrodictyon reticulatum and Pediastrum duplex, representing the largest of the Sphaeropleales sequenced thus far, once again highlight the variability in size, architecture, gene order and content across the Chlorophyceae. Novel intron insertion sites and unique

  18. Was Muller's 1946 Nobel Prize research for radiation-induced gene mutations peer-reviewed?

    Science.gov (United States)

    Calabrese, Edward J

    2018-06-06

    This historical analysis indicates that it is highly unlikely that the Nobel Prize winning research of Hermann J. Muller was peer-reviewed. The published paper of Muller lacked a research methods section, cited no references, and failed to acknowledge and discuss the work of Gager and Blakeslee (PNAS 13:75-79, 1927) that claimed to have induced gene mutation via ionizing radiation six months prior to Muller's non-data Science paper (Muller, Science 66(1699):84-87, 1927a). Despite being well acclimated into the scientific world of peer-review, Muller choose to avoid the peer-review process on his most significant publication. It appears that Muller's actions were strongly influenced by his desire to claim primacy for the discovery of gene mutation. The actions of Muller have important ethical lessons and implications today, when self-interest trumps one's obligations to society and the scientific culture that supports the quest for new knowledge and discovery.

  19. Genetic divergence between Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum (Siluriformes: Pimelodidae in the Paraná River Basin

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    TS. Bignotto

    Full Text Available Pseudoplatystoma corruscans (Spix and Agassiz, 1829 and Pseudoplatystoma reticulatum (Eingenmann and Eigenmann, 1889 are large migratory catfishes of high biological importance and great commercial value in South America. Because fertile crossbreeds can be artificially produced in hatcheries, a high genetic proximity between these two Pimelodidae species is conceivable. Possible escape of crossbred specimens from pisciculture stations is a serious environmental concern. Despite their importance, knowledge of P. corruscans and P. reticulatum biology, ecology, population diversity and genetics is limited. In the present work, the genetic divergence between P. corruscans and P. reticulatum populations from the Paraná River Basin was analyzed on the basis of polymorphisms in ISSR fragments and in the hypervariable sequence of the mitochondrial DNA (mtDNA control region. Estimates of intraspecific haplotype (h > 0.5 and nucleotide diversities (π < 0.01 indicate that P. corruscans and P. reticulatum have survived a historical population decline, followed by a demographic expansion. The interspecific polymorphisms within the mtDNA control region and ISSR fragments were suitable as diagnostic molecular markers and could be used to discriminate the two species. A unique Pseudoplatystoma specimen, captured in the Upper Paraná River Floodplain, was identified by these DNA diagnostic markers as a hybrid P. reticulatum x P. corruscans, which possibly escaped from pisciculture. The integrity of the natural population of P. corruscans in the Upper Paraná River is at risk of genetic introgression or homogenization due to the presence of hybrids and the transposition of P. reticulatum upstream through the Canal da Piracema at Itaipu Dam. Data presented herein improve the understanding of the genetic relatedness between P. corruscans and P. reticulatum and represent potential tools for future programs of conservation and surveillance of genetic introgression

  20. [Species composition and distribution of medical mollusca in Shanghai City].

    Science.gov (United States)

    Guo, Yun-hai; Lv, Shan; Gu, Wen-biao; Liu, He-xiang; Wu, Ying; Zhang, Yi

    2015-02-01

    To investigate the species diversity and distribution of medical mollusca in Shanghai City. From August 2012 to October 2013, all kinds of habitats in 8 districts and counties in Shanghai City, namely Jiading, Qingpu, Baoshan, Minhang, Songjiang, Jinshan, Chongming, Pudong, were selected for the field survey according to the distribution characteristics of the river system, and all the specimens of medical mollusca in the investigation sites were collected and classified by morphological identification. Meanwhile, the species composition, habitats as well as the fauna of the medical mollusca collected were analyzed. A total of 5,211 specimens were collected, which belonged to 2 classes, 14 families, 18 genera and 25 species, including Oncomelania hupensis hupensis, Pomacea canaliculata, Parafossarulus striatulus, Alocinma longicornis, Physa acuta, Galba pervia, Hippeutis cantori, etc. The species numbers of medical mollusca in Chongming, Jinshan, Pudong new area and Qingpu districts (counties) were 22, 22, 21 and 20, respectively, which were more than those of other areas. The habitat analysis suggested that the species numbers in the river and wetland were the most, both of which were 14 species. The main faunas of the medical mollusca in Shanghai were the cosmopolitan and oriental species. The freshwater gastropod species are paucity in Shanghai City, but almost of them can be served as the intermediate hosts of certain parasites to transmit snail-related parasitic diseases, so the surveillance of medical mollusca should be strengthened.

  1. Metabolism of 60Co in mollusca

    International Nuclear Information System (INIS)

    Nakahara, Motokazu

    1983-01-01

    After mollusca were bred in 60 Co-labeled sea water or were given 60 Co-labeled feed for certain hours, their tissues including the liver were removed as experimental samples. 60 Co metabolism was observed by the Sephadex gel filtration profile. A gel chromatogram of the liver in gastropoda showed a marked peak of 60 Co on the high-molecular side. Although the peak was observed on both high- and low-molecular sides in pelecypoda, it was more marked on the high-molecular side than on the low-molecular side. In cephalopoda, the peak pattern was similar to that in the other mollusca, but the proportion of low-molecular components was comparatively large. The gel filtration profile of 60 Co in various tissues of cephalopoda revealed the incorporation of 60 Co into the high-molecular components in blood, three peaks in the kidneys, and the incorporation of 60 Co into the low-molecular components in the branchial heart. The metabolism of 60 Co was dependent upon the chemical form of Co in gastropoda, and organic 60 Co was specifically observed in the high-molecular components. (Namekawa, K.)

  2. Accumulation of cesium-137 by useful mollusca

    International Nuclear Information System (INIS)

    Suzuki, Yuzuru; Nakahara, Motokazu; Nakamura, Ryoichi

    1978-01-01

    There are few data available on the radioactive contamination of marine mollusca, especially cephalopoda. Therefore, in this paper, data obtained on the radioactive contamination of cephalopoda were compared with those on pelecypoda and gastropoda. The uptake and elimination experiments were carried out by means of radioisotope tracer methods, and the concentration factors of 137 Cs due to radioactive fallout were estimated. The contamination of cephalopoda was also compared with those of other marine organisms in terms of concentration factor. The activity ratios in the organs or tissues of octopus were in the range of 3.5 and 12.8 on the 14th day after the beginning of exposure and those of squid were in the range of 8.8 and 10.9 on the 6th day after the commencement of the experiment. The biological half time was 90 days for octopus from the observation over 75 days, while it was 31 days for clam from the results of 75 days' experiment. The concentration factors of 137 Cs due to radioactive fallout were in the range of 3 and 23 for cephalopoda, 7 and 28 for pelecypoda and 24 and 30 for gastropoda, respectively. It was concluded that no difference in the concentration factors was clearly observable among the classes of mollusca, but the values were substantially similar to those of crustaceans and slightly lower than those of marine fish. (auth.)

  3. Science and Society in the Eugenic Thought of H. J. Muller

    Science.gov (United States)

    Allen, Garland E.

    1970-01-01

    Traces the growth of theories of eugenics during the twentieth century, focussing on the work of H. J. Muller. Concludes that "Muller's lasting contribution was to write the hereditarian attitudes associated with traditional eugenics and the environmentalist's viewpoint associated with modern sociology to obtain a humane and reasoned approach to…

  4. Geiger Muller (GM) detector as online monitor: an experimental study

    International Nuclear Information System (INIS)

    Jayan, M.P.; Pawar, V.J.; Krishnakumar, P.; Sureshkumar, M.

    2014-01-01

    Monitoring the inadvertent release of radioactivity into otherwise inactive liquid streams is a common requirement in nuclear industry. In addition to conventional off-line sampling and measurement methods, nuclear facilities usually uses online methods to get real-time detection of activity contents in process cooling water lines and steam condensate lines. Due to its simplicity, ruggedness and cost effectiveness, Geiger Muller counter is obviously the first choice for online application. Though GM based monitors for such online application were in industrial use for a long time, practical data on the response of the detector with respect low level activities in the effluents is scarce in literature. This work was carried out to fill this information gap. The data generated in these experiments may be useful in giving a realistic interpretation of the response of the existing monitors and setting up their alarm limits

  5. Biochemical features of a Protoceratium reticulatum red tide in Chipana Bay (Northern Chile in summer conditions

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    Sergio Rossi

    2010-11-01

    Full Text Available Protoceratium reticulatum is considered a potential toxic dinoflagellate. This paper describes a high-frequency monitoring study performed at Chipana Bay (northern Chile, sampling over 48 hours in a near-bottom shallow coastal area to quantify the biochemical features of a red tide dominated by this microscopic algae. This area belongs to the Humboldt Current upwelling system, and is considered highly productive for artisanal fisheries. Total chlorophyll a, total lipids, particulate organic carbon and nitrogen, fatty acids and major phytoplankton group concentration (i.e. dinoflagellates, diatoms, ciliates and cysts were studied in 7-hour intervals in February 2007. Our results indicate a high concentration of potential available food in the form of lipids ranging from 50 to 300 μg L-1 for benthic suspension feeders, i.e. bivalves. The dominance of P. reticulatum (60-80% of the total cell concentration per litre, ranging from 55x103 to 384x103 cells L-1 can be considered as a possible interference for harvesting in this productive area, although the toxicity of this algae was not proved in the present study. The main dinoflagellate fatty acid markers [18:0, 18:4(n-3, 20:5(n-3, and 22:6(n-3] showed high proportions (% during the short time cycle and in at least two cases [the 18:4 (n-3 and 22:6 (n-3 fatty acids] a highly significant relationship with dinoflagellate concentration (cells L-1. The topographical and benthic structure (mainly kelp forest of the zone helps to retain particles and nutrients that may in part explain the high productivity and food availability, but the presence of recurrent red tides in this coastal area—if they prove to be toxic—is argued to be a major problem for local fisheries.

  6. De nauwe korfslak Vertigo angustior in Nederland (Mollusca: Gastropoda)

    NARCIS (Netherlands)

    Bruyne, de R.

    2002-01-01

    The narrow whorlsnail Vertigo angustior in the Netherlands (Mollusca: Gastropoda) In June and July 2001, a special survey was held in several coastal areas in the province of Zuid- Holland, the Netherlands. The main objective was retrieving additional data on the occurrence of Vertigo angustior

  7. Overwinteringsgedrag van de nauwe korfslak Vertigo angustior (Mollusca)

    NARCIS (Netherlands)

    Boesveld, A.

    2005-01-01

    Overwintering habits of the land snail Vertigo angustior (Mollusca) During a mollusc survey in 2004 en 2005 in the province of Zuid-Holland special attention was paid to Vertigo angustior. The species was observed overwintering in large groups, up to hundreds of specimens together, between mosses

  8. Bibliographie der Flussperlmuschel Margaritifera Margaritifera (Linnaeus, 1758) [Mollusca: Pelecypoda

    NARCIS (Netherlands)

    Jungbluth, J.H.; Coomans, H.E.; Grohs, H.

    1985-01-01

    Bibliography of the freshwater Pearlmussel Margaritifera margaritifera (Linnaeus, 1758) [Mollusca: Pelecypoda] The freshwater pearlmussel, described by Linnaeus as Mya margaritifera is one of the most important molluscs existing. It belongs with only a few congeneric fossil and recent species to the

  9. Turning randomness into meaning at the molecular level using Muller's morphs.

    Science.gov (United States)

    Henson, Kathleen; Cooper, Melanie M; Klymkowsky, Michael W

    2012-04-15

    While evolutionary theory follows from observable facts and logical inferences (Mayr, 1985), historically, the origin of novel inheritable variations was a major obstacle to acceptance of natural selection (Bowler, 1992; Bowler, 2005). While molecular mechanisms address this issue (Jablonka and Lamb, 2005), analysis of responses to the Biological Concept Inventory (BCI) (Klymkowsky et al., 2010), revealed that molecular biology majors rarely use molecular level ideas in their discourse, implying that they do not have an accessible framework within which to place evolutionary variation. We developed a "Socratic tutorial" focused on Muller's categorization of mutations' phenotypic effects (Muller, 1932). Using a novel vector-based method to analyzed students' essay responses, we found that a single interaction with this tutorial led to significant changes in thinking toward a clearer articulation of the effects of mutational change. We suggest that Muller's morphs provides an effective framework for facilitating student learning about mutational effects and evolutionary mechanisms.

  10. Turning randomness into meaning at the molecular level using Muller's morphs

    Directory of Open Access Journals (Sweden)

    Kathleen Henson

    2012-02-01

    While evolutionary theory follows from observable facts and logical inferences (Mayr, 1985, historically, the origin of novel inheritable variations was a major obstacle to acceptance of natural selection (Bowler, 1992; Bowler, 2005. While molecular mechanisms address this issue (Jablonka and Lamb, 2005, analysis of responses to the Biological Concept Inventory (BCI (Klymkowsky et al., 2010, revealed that molecular biology majors rarely use molecular level ideas in their discourse, implying that they do not have an accessible framework within which to place evolutionary variation. We developed a “Socratic tutorial” focused on Muller's categorization of mutations' phenotypic effects (Muller, 1932. Using a novel vector-based method to analyzed students' essay responses, we found that a single interaction with this tutorial led to significant changes in thinking toward a clearer articulation of the effects of mutational change. We suggest that Muller's morphs provides an effective framework for facilitating student learning about mutational effects and evolutionary mechanisms.

  11. CONTROL DE BABOSAS (Deroceras reticulatum Müller) CON Phasmarhabditis hermaphrodita Schneider (NEMATODA: RHABDITIDAE) EN SUELOS CON SISTEMA DE CERO LABRANZA

    OpenAIRE

    France, Andrés; Gerding, Marcos; Céspedes, Cecilia; Cortez, Mónica

    2002-01-01

    Se evaluó el efecto del nemátodo Phasmarhabditis hermaphrodita (Schneider) en el control de babosas (Deroceras reticulatum Müller) en condiciones de laboratorio y campo. El nemátodo fue introducido desde Inglaterra. Luego de la cuarentena, P. hermaphrodita fue inoculado en D. reticulatum y evaluado diariamente por síntomas y mortalidad. En laboratorio el nemátodo causó la mortalidad de la totalidad de las poblaciones de babosas a los 20 días de postinoculación, produciendo una notoria disminu...

  12. A radioactivity study of mollusca distributed along the Syrian coast

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Ammar, I.; Mamish, S.; Haleem, M. A.

    2008-01-01

    In the present work, radioactivity has been studied in several Mollusca collected from four selected sites (Al Basset, Latakia, Banise and Tartous) along the Syrian coast. Concentration Factors (CF) of radionuclides (Lead-210, Polonium-210, Uranium Isotopes, Potassium-40 and Cesium-137) in mussels and shells of Mollusca have been calculated in order to determine the species that could be used as Bioindicators for these isotopes. Statistical analysis of the results using the box plot method showed that the mussels of Spondylus gaederopus spinosus and Chama pacifica can be used as biomonitor for the studied radionuclides in addition to shell of Strombus decorus persicus and Spondylus gaederopus spinosus. While the mussels of Brachidonta variabilis and Spondylus gaederopus spinosus have shown good selectivity for Cd and Pb and Pinctada radiate for Zn and Thais haemostoma for Cu. In addition, the migrant Mullusca from the Red Sea, Strombus decoruspersicus, can be used as biomonitor for lead, Zn and Cu, Cd, while the shell of Thais haemostoma for lead. However, the importance of the results of the present study that are considered as a baseline data for radionuclides in Mullusca distributed along the Syria coast and it is the only study in the eastern Mediterranean basin, that defined the Mollusca species which could be use as biomonitors for radionuclides. (Authors)

  13. A radioactivity study of mollusca distributed along the Syrian coast

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Ammar, I.; Mamish, S.; Haleem, M. A.

    2006-10-01

    In the present work, radioactivity has been studied in several Mollusca collected from four selected sites(Al Basset, Lattakia, Banise and Tartous) along the Syrian coast. Concentration Factors (CF) of radionuclides (Lead-210, Polonium-210, Uranium Isotopes, Potassium-40 and Cesium-137) in mussels and shells of Mollusca have been calculated in order to determine the species that could be used as Bioindicators for these isotopes. Statistical analysis of the results using the box plot method showed that the mussels of Spondylus spinosus and Chama pacifica can be used as biomonitor for the studied radionuclides in addition to shell of Strombus persicus and Spondylus spinosus. While the mussels of Brachidonta variabilis and Spondylus spinosus have shown good selectivity for Cd and Pb and Pinctada radiate for Zn and Thais haemostoma for Cu. In addition, the migrant Mullusca from the Red Sea, Strombus persicus, can be used as biomonitor for lead, Zn and Cu, Cd, while the shell of Thais haemostoma for lead. However, the importance of the results of the present study that are considered as a baseline data for radionuclides in Mullusca distributed along the Syria coast and it is the only study in the eastern Mediterranean basin, that defined the Mollusca species which could be use as biomonitors for radionuclides. (Authors)

  14. Complete mitochondrial genome from South American catfish Pseudoplatystoma reticulatum (Eigenmann & Eigenmann) and its impact in Siluriformes phylogenetic tree.

    Science.gov (United States)

    Villela, Luciana Cristine Vasques; Alves, Anderson Luis; Varela, Eduardo Sousa; Yamagishi, Michel Eduardo Beleza; Giachetto, Poliana Fernanda; da Silva, Naiara Milagres Augusto; Ponzetto, Josi Margarete; Paiva, Samuel Rezende; Caetano, Alexandre Rodrigues

    2017-02-01

    The cachara (Pseudoplatystoma reticulatum) is a Neotropical freshwater catfish from family Pimelodidae (Siluriformes) native to Brazil. The species is of relative economic importance for local aquaculture production and basic biological information is under development to help boost efforts to domesticate and raise the species in commercial systems. The complete cachara mitochondrial genome was obtained by assembling Illumina RNA-seq data from pooled samples. The full mitogenome was found to be 16,576 bp in length, showing the same basic structure, order, and genetic organization observed in other Pimelodidae, with 13 protein-coding genes, 2 rNA genes, 22 trNAs, and a control region. Observed base composition was 24.63% T, 28.47% C, 31.45% A, and 15.44% G. With the exception of NAD6 and eight tRNAs, all of the observed mitochondrial genes were found to be coded on the H strand. A total of 107 SNPs were identified in P. reticulatum mtDNA, 67 of which were located in coding regions. Of these SNPs, 10 result in amino acid changes. Analysis of the obtained sequence with 94 publicly available full Siluriformes mitogenomes resulted in a phylogenetic tree that generally agreed with available phylogenetic proposals for the order. The first report of the complete Pseudoplatystoma reticulatum mitochondrial genome sequence revealed general gene organization, structure, content, and order similar to most vertebrates. Specific sequence and content features were observed and may have functional attributes which are now available for further investigation.

  15. Quantifying the threat of extinction from Muller's ratchet in the diploid Amazon molly (Poecilia formosa

    Directory of Open Access Journals (Sweden)

    Loewe Laurence

    2008-03-01

    Full Text Available Abstract Background The Amazon molly (Poecilia formosa is a small unisexual fish that has been suspected of being threatened by extinction from the stochastic accumulation of slightly deleterious mutations that is caused by Muller's ratchet in non-recombining populations. However, no detailed quantification of the extent of this threat is available. Results Here we quantify genomic decay in this fish by using a simple model of Muller's ratchet with the most realistic parameter combinations available employing the evolution@home global computing system. We also describe simple extensions of the standard model of Muller's ratchet that allow us to deal with selfing diploids, triploids and mitotic recombination. We show that Muller's ratchet creates a threat of extinction for the Amazon molly for many biologically realistic parameter combinations. In most cases, extinction is expected to occur within a time frame that is less than previous estimates of the age of the species, leading to a genomic decay paradox. Conclusion How then does the Amazon molly survive? Several biological processes could individually or in combination solve this genomic decay paradox, including paternal leakage of undamaged DNA from sexual sister species, compensatory mutations and many others. More research is needed to quantify the contribution of these potential solutions towards the survival of the Amazon molly and other (ancient asexual species.

  16. Susceptibility of the eggs of the field slug Deroceras reticulatum to contact with pesticides and substances of biological origin on artificial soil

    NARCIS (Netherlands)

    Iglesias, J.; Castillejo, J.; Ester, A.; Castro, R.; Lombardia, M.J.

    2002-01-01

    The toxicity of 14 substances, including a number of pesticides, to the eggs of the pest slug Deroceras reticulatum was determined in laboratory experiments. Eggs were kept in contact with a precisely defined artificial soil to which a range of concentrations of the test substances had been applied.

  17. Taxonomy of the Caribbean sponge Dragmacidon reticulatum (Ridley & Dendy, 1886) (Porifera, Demospongiae, Axinellida), with the description of a new species.

    Science.gov (United States)

    Zea, Sven; Pulido, Alejandra

    2016-05-25

    Although there is a long history of taxonomic investigation in Caribbean sponges, there are still many undescribed species. Furthermore, field observations and corroborating morphological analyses are revealing that what was believed to be single, somewhat variable species, may consist of two or more species, often easier to distinguish once well characterized. This is the case for Dragmacidon reticulatum (Ridley & Dendy, 1886) (Porifera, Demospongiae, Axinellida, Axinellidae), a rather well-known sponge, with an ample distribution and presence in rocky and reef environments of the tropical and subtropical Western Atlantic, with local records in the majority of the countries of the area, from Bermuda to Brazil. Field observations and a detailed review of material from different areas, including some type specimens, led us to the distinction of two different species in terms of external morphology, size of spicules, and skeletal architecture. The distinction was confirmed in the Bahamas and Santa Marta, Colombia, where the two species coexist. One of the species is Dragmacidon reticulatum sensu stricto, but for the other there is need to erect a new name, for which we propose Dragmacidon alvarezae n. sp. The purpose of the present work is to describe, illustrate and compare these two species.

  18. Characterization of the early development of Pseudoplatystoma reticulatum Eigenmann & Eigenmann, 1889 (Siluriformes: Pimelodidae from the Paraguay River Basin

    Directory of Open Access Journals (Sweden)

    Fernanda F. Andrade

    Full Text Available ABSTRACT This study described the initial development of Pseudoplatystoma reticulatum, as well as changes in growth patterns. Morphometric and meristic variables were analyzed during embryonic, larval and juvenile periods, even as allometric growth coefficients for larvae and juveniles. Eggs showed an average diameter of 1.79 mm and broad perivitelline space (23.41%. The total length (TL of the larvae ranged from 3.05 to 25.72 mm, and the total number of myomeres ranged from 45 to 50 (preanal = 13-16 and postanal = 30-35. Initial pigmentation is poor, concentrated at the extremities of the yolk sac. In the flexion stage, the pigmentation intensifies and forms a longitudinal stripe extending from the snout to the operculum and two longitudinal stripes on the body, one dorsal and the other ventral, that unite at the caudal peduncle. At first, there is a differential growth of the head and tail, and then there is the growth of the body, which shows changes in the ontogenetic priorities of feeding, swimming, and breathing capacities. Our results are very important for ecology, systematics, and hatchering, especially in terms of ontogenetic variation in morphology, growth, feeding, behavior, and mortality of P. reticulatum.

  19. Draft genome sequence of Cicer reticulatum L., the wild progenitor of chickpea provides a resource for agronomic trait improvement.

    Science.gov (United States)

    Gupta, Sonal; Nawaz, Kashif; Parween, Sabiha; Roy, Riti; Sahu, Kamlesh; Kumar Pole, Anil; Khandal, Hitaishi; Srivastava, Rishi; Kumar Parida, Swarup; Chattopadhyay, Debasis

    2017-02-01

    Cicer reticulatum L. is the wild progenitor of the fourth most important legume crop chickpea (C. arietinum L.). We assembled short-read sequences into 416 Mb draft genome of C. reticulatum and anchored 78% (327 Mb) of this assembly to eight linkage groups. Genome annotation predicted 25,680 protein-coding genes covering more than 90% of predicted gene space. The genome assembly shared a substantial synteny and conservation of gene orders with the genome of the model legume Medicago truncatula. Resistance gene homologs of wild and domesticated chickpeas showed high sequence homology and conserved synteny. Comparison of gene sequences and nucleotide diversity using 66 wild and domesticated chickpea accessions suggested that the desi type chickpea was genetically closer to the wild species than the kabuli type. Comparative analyses predicted gene flow between the wild and the cultivated species during domestication. Molecular diversity and population genetic structure determination using 15,096 genome-wide single nucleotide polymorphisms revealed an admixed domestication pattern among cultivated (desi and kabuli) and wild chickpea accessions belonging to three population groups reflecting significant influence of parentage or geographical origin for their cultivar-specific population classification. The assembly and the polymorphic sequence resources presented here would facilitate the study of chickpea domestication and targeted use of wild Cicer germplasms for agronomic trait improvement in chickpea. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  20. Regulation of Taurine transporter activity in cultured rat retinal ganglion cells and rat retinal Muller Cells

    International Nuclear Information System (INIS)

    Eissa, Laila A.; Smith, Sylvia B.; El-sherbeny, Amira A.

    2006-01-01

    Diabetic retinopathy is one of the most common complications of diabetes. The amino acid taurine is believed to play an antioxidant protective role in diabetic retinopathy through the scavenging of the reactive species. It is not well established whether taurine uptake is altered in retina cells during diabetic conditions. Thus, the present study was designed to investigate the changes in taurine transport in cultures of rat retinal Muller cells and rat retinal ganglion cells under conditions associated with diabetes. Taurine was abundantly taken up by retinal Muller cells and rat retinal ganglion cells under normal glycemic condition. Taurine was actively transported to rat Muller cells and rat retinal ganglion cells in a Na and Cl dependant manner. Taurine uptake further significantly elevated in both type of cells after the incubation with high glucose concentration. This effect could be attributed to the increase in osmolarity. Because Nitric Oxide (NO) is a molecule implicated in the pathogenesis of diabetes, we also determined the activity of taurine transporter in cultured rat retinal Muller cells and rat retinal ganglion cells in the presence of the NO donors, SIN-1 and SNAP. Taurine uptake was elevated above control value after 24-h incubation with low concentration of NO donors. We finally investigated the ability of neurotoxic glutamate to change taurine transporter activity in both types of cells. Uptake of taurine was significantly increased in rat retinal ganglion cells when only incubated with high concentration of glutamate. Our data provide evidence that taurine transporter is present in cultured rat retinal ganglion and Muller cells and is regulated by hyperosmolarity. The data are relevant to disease such as diabetes and neuronal degeneration where retinal cell volume may dramatically change. (author)

  1. Types of Cenozoic Mollusca from Java in the Martin Collection of Naturalis

    NARCIS (Netherlands)

    Leloux, J.; Wesselingh, F.P.

    2009-01-01

    An updated type catalogue of the Martin Collection (fossil Mollusca, predominantly from the Cenozoic of Java, Indonesia) is presented. Type specimen data, updated locality data, and illustrations are given.

  2. Pentaplacodinium saltonense gen. et sp. nov. (Dinophyceae) and its relationship to the cyst-defined genus Operculodinium and yessotoxin-producing Protoceratium reticulatum

    DEFF Research Database (Denmark)

    Mertens, Kenneth Neil; Carbonell-Moore, M. Consuelo; Pospelova, Vera

    2018-01-01

    Strains of a dinoflagellate from the Salton Sea, previously identified as Protoceratium reticulatum and yessotoxin producing, have been reexamined morphologically and genetically and Pentaplacodinium saltonense n. gen. et sp. is erected to accommodate this species. Pentaplacodinium saltonense dif...

  3. Geiger-Muller with a mica window halogen quenched counters aspects

    International Nuclear Information System (INIS)

    Gorski, M.S.; Bruzinga, W.A.

    1990-09-01

    We present the development of a model of a Geiger-Muller with likeness the model ZP 1410 Phillips. The prototype has a cylindrical shape with 37mm of effective length and a mica window of 1,5 to 2,0mg/cm sup(2) thickness with a useful diam of 19,8mm. For the window preparation and special cutting technique was developed Basically two types of quenching agents, bromine and chlorine were studied. Due to the high corrosive nature of these gases, we work with treatment of surface of the cathode through electropolishment, chemical passiveness, hard chrome and nickel coating. Out main objective was to get a Geiger-Muller detector with an operational plateau over 200V, working voltage above 600V and a sensivity of 320 counts/sec at 10 sup(-1) m Gy/h. (author)

  4. Geiger-Muller (GM) counters. Associated circuits and counting techniques; Les compteurs de Geiger-Muller (GM). Les circuits associes et techniques de comptage

    Energy Technology Data Exchange (ETDEWEB)

    Benoit, A.; Picard, E. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay (France)

    1954-07-01

    This article presents the Geiger-Muller counters which present the great benefit of being simple and steady in comparison with other known sensors. The authors propose an overview of problems related to the use of Geiger-Muller counters (GM counters). They first describe their operation (discharge initiation, discharge propagation, collection of positive ions and current in the counter). They discuss their limitations which are related to the migration delay of primary electrons and positive ions. They describe the operation circuit for counters with organic vapour, and for counters associated with counters using halogens. They address the main properties of GM counters, and the different factors to be taken into account when using them to count radioactive sources. The main types of GM counters are then described (they are used to measure different types of radiation). Measurement techniques are discussed for beta radiation (relationship between the number of disintegrations and the noticed counting rate, case of backscattering, absorption and diffusion in the counter window and in the air, influence of absorption and backscattering in the source), for alpha radiation, and for gamma radiation.

  5. Seasonal variability of Dinophysis spp. and Protoceratium reticulatum associated to lipophilic shellfish toxins in a strongly stratified Chilean fjord

    Science.gov (United States)

    Alves-de-Souza, Catharina; Varela, Daniel; Contreras, Cristóbal; de La Iglesia, Pablo; Fernández, Pamela; Hipp, Byron; Hernández, Cristina; Riobó, Pilar; Reguera, Beatriz; Franco, José M.; Diogène, Jorge; García, Carlos; Lagos, Néstor

    2014-03-01

    The fine scale vertical distribution of Dinophysis spp. and Protoceratium reticulatum (potential producers of lipophilic shellfish toxins, LSTs) and its relation with LSTs in shellfish was studied in Reloncaví fjord, a strongly stratified system in Southern Chile. Samples were taken over two years from late spring to early autumn (2007-2008 period) and from early spring to late summer (2008-2009 period). Dinophysis spp., in particular Dinophysis acuminata, were always detected, often forming thin layers in the region of the salinity driven pycnocline, with cell maxima for D. acuminata of 28.5×103 cells L-1 in March 2008 and 17.1×103 cells L-1 in November 2008. During the 2008-2009 sampling period, blooms of D. acuminata co-occurred with high densities of cryptophyceans and the ciliate Mesodinium spp. The highest levels of pectenotoxin-2 (PTX-2; 2.2 ng L-1) were found in the plankton in February 2009, associated with moderate densities of D. acuminata, Dinophysis tripos and Dinophysis subcircularis (0.1-0.6×103 cells L-1). However, only trace levels of PTX-2 were observed in bivalves at that time. Dinophysistoxin (DTX-1 and DTX-3) levels in bivalves and densities of Dinophysis spp. were not well correlated. Low DTX levels in bivalves observed during a major bloom of D. acuminata in March 2008 suggested that there is a large seasonal intraspecific variability in toxin content of Dinophysis spp. driven by changes in population structure associated with distinct LST toxin profiles in Reloncaví fjord during the study period. A heterogeneous vertical distribution was also observed for P. reticulatum, whose presence was restricted to summer months. A bloom of this species of 2.2×103 cells L-1 at 14 m depth in February 2009 was positively correlated with high concentrations of yessotoxins in bivalves (51-496 ng g-1) and plankton samples (3.2 ng L-1). Our results suggest that a review of monitoring strategies for Dinophysis spp. in strongly stratified fjord systems

  6. "ON ALGEBRAIC DECODING OF Q-ARY REED-MULLER AND PRODUCT REED-SOLOMON CODES"

    Energy Technology Data Exchange (ETDEWEB)

    SANTHI, NANDAKISHORE [Los Alamos National Laboratory

    2007-01-22

    We consider a list decoding algorithm recently proposed by Pellikaan-Wu for q-ary Reed-Muller codes RM{sub q}({ell}, m, n) of length n {le} q{sup m} when {ell} {le} q. A simple and easily accessible correctness proof is given which shows that this algorithm achieves a relative error-correction radius of {tau} {le} (1-{radical}{ell}q{sup m-1}/n). This is an improvement over the proof using one-point Algebraic-Geometric decoding method given in. The described algorithm can be adapted to decode product Reed-Solomon codes. We then propose a new low complexity recursive aJgebraic decoding algorithm for product Reed-Solomon codes and Reed-Muller codes. This algorithm achieves a relative error correction radius of {tau} {le} {Pi}{sub i=1}{sup m} (1 - {radical}k{sub i}/q). This algorithm is then proved to outperform the Pellikaan-Wu algorithm in both complexity and error correction radius over a wide range of code rates.

  7. Fault-tolerant conversion between adjacent Reed-Muller quantum codes based on gauge fixing

    Science.gov (United States)

    Quan, Dong-Xiao; Zhu, Li-Li; Pei, Chang-Xing; Sanders, Barry C.

    2018-03-01

    We design forward and backward fault-tolerant conversion circuits, which convert between the Steane code and the 15-qubit Reed-Muller quantum code so as to provide a universal transversal gate set. In our method, only seven out of a total 14 code stabilizers need to be measured, and we further enhance the circuit by simplifying some stabilizers; thus, we need only to measure eight weight-4 stabilizers for one round of forward conversion and seven weight-4 stabilizers for one round of backward conversion. For conversion, we treat random single-qubit errors and their influence on syndromes of gauge operators, and our novel single-step process enables more efficient fault-tolerant conversion between these two codes. We make our method quite general by showing how to convert between any two adjacent Reed-Muller quantum codes \\overline{\\textsf{RM}}(1,m) and \\overline{\\textsf{RM}}≤ft(1,m+1\\right) , for which we need only measure stabilizers whose number scales linearly with m rather than exponentially with m obtained in previous work. We provide the explicit mathematical expression for the necessary stabilizers and the concomitant resources required.

  8. Description and phylogeny of a new microsporidium from the elm leaf beetle, Xanthogaleruca luteola Muller, 1766 (Coleoptera: Chrysomelidae)

    Science.gov (United States)

    This study describes a new genus and species of microsporidia which is a pathogen of the elm leaf beetle, Xanthogaleruca luteola Muller, 1776 (Coleoptera: Chrysomelidae). The beetles were collected from Istanbul in Turkey. All developmental stages are uninucleate and in direct contact with the host ...

  9. On six species of marine Mollusca from suriname, four of which are new

    NARCIS (Netherlands)

    Regteren, van C.O.

    1971-01-01

    Four new species are here described in order to have their descriptions published before "Seashells of Wia Wia" by D. J. Green & R. H. Hill and the second part of my paper on the Holocene and Recent marine Mollusca of Suriname will appear. Notes are added on two species for which names are used

  10. On fossil Mollusca from the island of Mandul, East-Borneo

    NARCIS (Netherlands)

    Beets, C.

    1950-01-01

    This paper presents the results of the examination of a fairly big collection of mollusca from the island of Mandul, north of Tarakan, East-Borneo. The material was collected by Dr. Van Holst Pellekaan while investigating the geology of Mandul in the service of the “Bataafsche Petroleum

  11. On locality of Generalized Reed-Muller codes over the broadcast erasure channel

    KAUST Repository

    Alloum, Amira

    2016-07-28

    One to Many communications are expected to be among the killer applications for the currently discussed 5G standard. The usage of coding mechanisms is impacting broadcasting standard quality, as coding is involved at several levels of the stack, and more specifically at the application layer where Rateless, LDPC, Reed Slomon codes and network coding schemes have been extensively studied, optimized and standardized in the past. Beyond reusing, extending or adapting existing application layer packet coding mechanisms based on previous schemes and designed for the foregoing LTE or other broadcasting standards; our purpose is to investigate the use of Generalized Reed Muller codes and the value of their locality property in their progressive decoding for Broadcast/Multicast communication schemes with real time video delivery. Our results are meant to bring insight into the use of locally decodable codes in Broadcasting. © 2016 IEEE.

  12. Tear function and ocular surface after Muller muscle-conjunctival resection.

    Science.gov (United States)

    Uğurbaş, Suat Hayri; Alpay, Atilla; Bahadır, Burak; Uğurbaş, Sılay Cantürk

    2014-05-01

    Muller muscle-conjunctival resection (MCR) is a surgical technique to correct mild and moderate ptosis. In this study, tear function tests and ocular surface are evaluated in patients who underwent unilateral surgery. Sixteen patients with normal preoperative tear function who underwent unilateral MCR were evaluated prospectively. The fellow eyes of the patients were taken as the control group. A dry eye assessment questionnaire, Schirmer testing, tear film break-up time, fluorescein stain, Rose-Bengal stain, and conjunctival impression cytology were used to assess the tear film functions and ocular surface changes in the operated and non-operated eyes. There was no statistically significant difference in the tear function tests and goblet cell densities between the operated and non-operated eyes. The results indicate that an MCR procedure has no apparent effect on tear function tests and goblet cell density in patients with normal preoperative tear function.

  13. Comparative genomics of vesicomyid clam (Bivalvia: Mollusca chemosynthetic symbionts

    Directory of Open Access Journals (Sweden)

    Girguis Peter R

    2008-12-01

    Full Text Available Abstract Background The Vesicomyidae (Bivalvia: Mollusca are a family of clams that form symbioses with chemosynthetic gamma-proteobacteria. They exist in environments such as hydrothermal vents and cold seeps and have a reduced gut and feeding groove, indicating a large dependence on their endosymbionts for nutrition. Recently, two vesicomyid symbiont genomes were sequenced, illuminating the possible nutritional contributions of the symbiont to the host and making genome-wide evolutionary analyses possible. Results To examine the genomic evolution of the vesicomyid symbionts, a comparative genomics framework, including the existing genomic data combined with heterologous microarray hybridization results, was used to analyze conserved gene content in four vesicomyid symbiont genomes. These four symbionts were chosen to include a broad phylogenetic sampling of the vesicomyid symbionts and represent distinct chemosynthetic environments: cold seeps and hydrothermal vents. Conclusion The results of this comparative genomics analysis emphasize the importance of the symbionts' chemoautotrophic metabolism within their hosts. The fact that these symbionts appear to be metabolically capable autotrophs underscores the extent to which the host depends on them for nutrition and reveals the key to invertebrate colonization of these challenging environments.

  14. The final spawning ground of Tachypleus gigas (Muller, 1785) on the east Peninsular Malaysia is at risk: A call for action.

    Digital Repository Service at National Institute of Oceanography (India)

    Nelson, B.R.; Satyanarayan, B.; Moh, J.H.Z.; Ikhwanuddin, M.; Chatterji, A.; Shaharom, F.

    Tanjung Selongor and Pantai Balok (State Pahang) are the only two places known for spawning activity of the Malaysian horseshoe crab - Tachypleus gigas (Muller, 1785) on the east coast of Peninsular Malaysia. While the former beach has been...

  15. André B. Muller (25.9.1918-1.4.2006)

    Science.gov (United States)

    West, R. M.

    2006-06-01

    With great sadness, we have learned about the death of André Muller on 1 April, at the age of 87. Living in retirement in his native Holland since 1983, he was one of ESOs true pioneers, an outstanding representative of the select group of European astronomers who succeeded in steering ESO through the difficult initial phases. André was close-ly associated with the entire process, from the first site monitoring programmes in South Africa to the subsequent search in Chile, the decision in favour of the La Silla site, as well as the management of ESOs early activities in Chile, includ-ing the construction of the headquarters and observatory and the installation of the first generation of ESO telescopes. Few persons, if any, have been so inti-mately connected to the setting-up of ESOs facilities and it would be impossible to list in detail all of the services André performed for the organisation with such great expertise and zeal during his long career.

  16. Performances of Dose Measurement of Commercial Electronic Dosimeters using Geiger Muller Tube and PIN Diode

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Hyunjun; Kim, Chankyu; Kim, Yewon; Kim, Giyoon; Cho, Gyuseong [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    There are two categories in personal dosimeters, one is passive type dosimeter such as TLD (thermoluminescence dosimeter) and the other is active type dosimeter such as electronic dosimeter can show radiation dose immediately while TLD needs long time to readout its data by heating process. For improving the reliability of measuring dose for any energy of radiations, electronic dosimeter uses energy filter by metal packaging its detector using aluminum or copper, but measured dose of electronic dosimeter with energy filter cannot be completely compensated in wide radiation energy region. So, in this paper, we confirmed the accuracy of dose measurement of two types of commercial EPDs using Geiger Muller tube and PIN diode with CsI(Tl) scintillator in three different energy of radiation field. The experiment results for Cs-137 was almost similar with calculation value in the results of both electronic dosimeters, but, the other experiment values with Na-22 and Co-60 had higher error comparing with Cs-137. These results were caused by optimization of their energy filters. The optimization was depending on its thickness of energy filter. So, the electronic dosimeters have to optimizing the energy filter for increasing the accuracy of dose measurement or the electronic dosimeter using PIN diode with CsI(Tl) scintillator uses the multi-channel discriminator for using its energy information.

  17. Clonal interference and Muller's ratchet in spatial habitats

    International Nuclear Information System (INIS)

    Otwinowski, Jakub; Krug, Joachim

    2014-01-01

    Competition between independently arising beneficial mutations is enhanced in spatial populations due to the linear rather than exponential growth of clones. Recent theoretical studies have pointed out that the resulting fitness dynamics is analogous to a surface growth process, where new layers nucleate and spread stochastically, leading to the build up of scale-invariant roughness. This scenario differs qualitatively from the standard view of adaptation in that the speed of adaptation becomes independent of population size while the fitness variance does not. Here we exploit recent progress in the understanding of surface growth processes to obtain precise predictions for the universal, non-Gaussian shape of the fitness distribution for one-dimensional habitats, which are verified by simulations. When the mutations are deleterious rather than beneficial the problem becomes a spatial version of Muller's ratchet. In contrast to the case of well-mixed populations, the rate of fitness decline remains finite even in the limit of an infinite habitat, provided the ratio U d /s 2 between the deleterious mutation rate and the square of the (negative) selection coefficient is sufficiently large. Using, again, an analogy to surface growth models we show that the transition between the stationary and the moving state of the ratchet is governed by directed percolation. (paper)

  18. Infestação de Aetalion reticulatum (Linnaeus (Hemiptera: Auchenorrhyncha: Aethalionidae em Plantas de Euterpe oleracea Martius (Arecaceae no Estado do Acre

    Directory of Open Access Journals (Sweden)

    Rodrigo Santos

    2015-04-01

    Abstract. The açai palm (Euterpe oleracea Martius is a native palm tree from the Amazon region floodplains and may be indicated as the most economically profitable species of this genus. Its fruit pulp is extracted and widely consumed by the population of northern Brazil in several ways. With the expansion of the planted area many factors may affect the production and limit the cultivation, highlighting the occurrence of insect pests that cause losses in production. This report presents the first occurrence of the leafhopper Aetalion reticulatum (Linnaeus (Hemiptera: Auchenorrhyncha: Aethalionidae in E. oleracea plants. The occurrence of this insect associated with açai palms in Rio Branco, Acre, increases the list of hosts for this leafhopper in Brazil and reinforces the need for studies of population dynamics, survey of natural enemies, levels of damage and control methods in order to anticipate population outbreaks of this pest in commercial plantations of açai palms in the State.

  19. Cebos molusquicidas y molusquicidas líquidos para el control de Deroceras reticulatum (Pulmonata: Stylomatophora, plaga en el cultivo de colza

    Directory of Open Access Journals (Sweden)

    GARAVANO, M.E.

    2013-04-01

    Full Text Available Oil seed rape (Brassica napus under No Tillage (NT represents an alternative in the current crop rotationsystems. Deroceras reticulatum “gray slug” is a one of the present pest in this crop under NT. The aim of thisstudy was to evaluate combined action bait and liquid Metaldehyde as an alternative strategy control of the specie. Laboratory and fields traits were carried out with the following treatments: control treatment without chemicals, chemical co tro (4 kg ha-1 of Metaldehyde 4 %, 3, 4 and 5 kg ha-1 combined action bait (Carbaryl8 % y Metaldehyde 4 % and 1, 2 and 3 l ha-1 of liquid formulations (20 % Metaldehyde. The number of dead individuals of D. reticulatum and the number of damaged and undamaged plants were evaluated. In the laboratory,up to 3 days after application (DAA it was observed higher control rates at all doses of liquid formulationthan all solids treatment. In both, solid and liquid treatments did not have doses effect. The proportion of damaged plants did not differ between treatments. In the field, at 2, 8 and 14 DAA liquid treatments showed lower control rates compared with the Metaldehyde baits and combined action bait. Both treatments solids and liquids were no effect of dose. The proportion of damaged plants was higher than that observed in laboratoryconditions. There were not observed differences in the proportion of damaged plants under chemical treatments and in the control with slugs. The application of liquid formulations may be carrying out close to crops sowing, while baits should be applied before sowing.

  20. Retrotransposons Are the Major Contributors to the Expansion of the Drosophila ananassae Muller F Element.

    Science.gov (United States)

    Leung, Wilson; Shaffer, Christopher D; Chen, Elizabeth J; Quisenberry, Thomas J; Ko, Kevin; Braverman, John M; Giarla, Thomas C; Mortimer, Nathan T; Reed, Laura K; Smith, Sheryl T; Robic, Srebrenka; McCartha, Shannon R; Perry, Danielle R; Prescod, Lindsay M; Sheppard, Zenyth A; Saville, Ken J; McClish, Allison; Morlock, Emily A; Sochor, Victoria R; Stanton, Brittney; Veysey-White, Isaac C; Revie, Dennis; Jimenez, Luis A; Palomino, Jennifer J; Patao, Melissa D; Patao, Shane M; Himelblau, Edward T; Campbell, Jaclyn D; Hertz, Alexandra L; McEvilly, Maddison F; Wagner, Allison R; Youngblom, James; Bedi, Baljit; Bettincourt, Jeffery; Duso, Erin; Her, Maiye; Hilton, William; House, Samantha; Karimi, Masud; Kumimoto, Kevin; Lee, Rebekah; Lopez, Darryl; Odisho, George; Prasad, Ricky; Robbins, Holly Lyn; Sandhu, Tanveer; Selfridge, Tracy; Tsukashima, Kara; Yosif, Hani; Kokan, Nighat P; Britt, Latia; Zoellner, Alycia; Spana, Eric P; Chlebina, Ben T; Chong, Insun; Friedman, Harrison; Mammo, Danny A; Ng, Chun L; Nikam, Vinayak S; Schwartz, Nicholas U; Xu, Thomas Q; Burg, Martin G; Batten, Spencer M; Corbeill, Lindsay M; Enoch, Erica; Ensign, Jesse J; Franks, Mary E; Haiker, Breanna; Ingles, Judith A; Kirkland, Lyndsay D; Lorenz-Guertin, Joshua M; Matthews, Jordan; Mittig, Cody M; Monsma, Nicholaus; Olson, Katherine J; Perez-Aragon, Guillermo; Ramic, Alen; Ramirez, Jordan R; Scheiber, Christopher; Schneider, Patrick A; Schultz, Devon E; Simon, Matthew; Spencer, Eric; Wernette, Adam C; Wykle, Maxine E; Zavala-Arellano, Elizabeth; McDonald, Mitchell J; Ostby, Kristine; Wendland, Peter; DiAngelo, Justin R; Ceasrine, Alexis M; Cox, Amanda H; Docherty, James E B; Gingras, Robert M; Grieb, Stephanie M; Pavia, Michael J; Personius, Casey L; Polak, Grzegorz L; Beach, Dale L; Cerritos, Heaven L; Horansky, Edward A; Sharif, Karim A; Moran, Ryan; Parrish, Susan; Bickford, Kirsten; Bland, Jennifer; Broussard, Juliana; Campbell, Kerry; Deibel, Katelynn E; Forka, Richard; Lemke, Monika C; Nelson, Marlee B; O'Keeffe, Catherine; Ramey, S Mariel; Schmidt, Luke; Villegas, Paola; Jones, Christopher J; Christ, Stephanie L; Mamari, Sami; Rinaldi, Adam S; Stity, Ghazal; Hark, Amy T; Scheuerman, Mark; Silver Key, S Catherine; McRae, Briana D; Haberman, Adam S; Asinof, Sam; Carrington, Harriette; Drumm, Kelly; Embry, Terrance; McGuire, Richard; Miller-Foreman, Drew; Rosen, Stella; Safa, Nadia; Schultz, Darrin; Segal, Matt; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Skuse, Gary; Paetkau, Don W; Bridgman, Rachael K; Brown, Charlotte M; Carroll, Alicia R; Gifford, Francesca M; Gillespie, Julie Beth; Herman, Susan E; Holtcamp, Krystal L; Host, Misha A; Hussey, Gabrielle; Kramer, Danielle M; Lawrence, Joan Q; Martin, Madeline M; Niemiec, Ellen N; O'Reilly, Ashleigh P; Pahl, Olivia A; Quintana, Guadalupe; Rettie, Elizabeth A S; Richardson, Torie L; Rodriguez, Arianne E; Rodriguez, Mona O; Schiraldi, Laura; Smith, Joanna J; Sugrue, Kelsey F; Suriano, Lindsey J; Takach, Kaitlyn E; Vasquez, Arielle M; Velez, Ximena; Villafuerte, Elizabeth J; Vives, Laura T; Zellmer, Victoria R; Hauke, Jeanette; Hauser, Charles R; Barker, Karolyn; Cannon, Laurie; Parsamian, Perouza; Parsons, Samantha; Wichman, Zachariah; Bazinet, Christopher W; Johnson, Diana E; Bangura, Abubakarr; Black, Jordan A; Chevee, Victoria; Einsteen, Sarah A; Hilton, Sarah K; Kollmer, Max; Nadendla, Rahul; Stamm, Joyce; Fafara-Thompson, Antoinette E; Gygi, Amber M; Ogawa, Emmy E; Van Camp, Matt; Kocsisova, Zuzana; Leatherman, Judith L; Modahl, Cassie M; Rubin, Michael R; Apiz-Saab, Susana S; Arias-Mejias, Suzette M; Carrion-Ortiz, Carlos F; Claudio-Vazquez, Patricia N; Espada-Green, Debbie M; Feliciano-Camacho, Marium; Gonzalez-Bonilla, Karina M; Taboas-Arroyo, Mariela; Vargas-Franco, Dorianmarie; Montañez-Gonzalez, Raquel; Perez-Otero, Joseph; Rivera-Burgos, Myrielis; Rivera-Rosario, Francisco J; Eisler, Heather L; Alexander, Jackie; Begley, Samatha K; Gabbard, Deana; Allen, Robert J; Aung, Wint Yan; Barshop, William D; Boozalis, Amanda; Chu, Vanessa P; Davis, Jeremy S; Duggal, Ryan N; Franklin, Robert; Gavinski, Katherine; Gebreyesus, Heran; Gong, Henry Z; Greenstein, Rachel A; Guo, Averill D; Hanson, Casey; Homa, Kaitlin E; Hsu, Simon C; Huang, Yi; Huo, Lucy; Jacobs, Sarah; Jia, Sasha; Jung, Kyle L; Wai-Chee Kong, Sarah; Kroll, Matthew R; Lee, Brandon M; Lee, Paul F; Levine, Kevin M; Li, Amy S; Liu, Chengyu; Liu, Max Mian; Lousararian, Adam P; Lowery, Peter B; Mallya, Allyson P; Marcus, Joseph E; Ng, Patrick C; Nguyen, Hien P; Patel, Ruchik; Precht, Hashini; Rastogi, Suchita; Sarezky, Jonathan M; Schefkind, Adam; Schultz, Michael B; Shen, Delia; Skorupa, Tara; Spies, Nicholas C; Stancu, Gabriel; Vivian Tsang, Hiu Man; Turski, Alice L; Venkat, Rohit; Waldman, Leah E; Wang, Kaidi; Wang, Tracy; Wei, Jeffrey W; Wu, Dennis Y; Xiong, David D; Yu, Jack; Zhou, Karen; McNeil, Gerard P; Fernandez, Robert W; Menzies, Patrick Gomez; Gu, Tingting; Buhler, Jeremy; Mardis, Elaine R; Elgin, Sarah C R

    2017-08-07

    The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster , but it is substantially larger (>18.7 Mb) in D. ananassae To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes ( e.g. , larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae Compared to D. melanogaster , the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5' ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains. Copyright © 2017 Leung et al.

  1. Retrotransposons Are the Major Contributors to the Expansion of the Drosophila ananassae Muller F Element

    Directory of Open Access Journals (Sweden)

    Wilson Leung

    2017-08-01

    Full Text Available The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb in D. ananassae. To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons are major contributors to this expansion (78.6%, while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%. Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias, but these differences are exaggerated in D. ananassae. Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5′ ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2, while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains.

  2. Retrotransposons Are the Major Contributors to the Expansion of the Drosophila ananassae Muller F Element

    Science.gov (United States)

    Shaffer, Christopher D.; Chen, Elizabeth J.; Quisenberry, Thomas J.; Ko, Kevin; Braverman, John M.; Giarla, Thomas C.; Mortimer, Nathan T.; Reed, Laura K.; Smith, Sheryl T.; Robic, Srebrenka; McCartha, Shannon R.; Perry, Danielle R.; Prescod, Lindsay M.; Sheppard, Zenyth A.; Saville, Ken J.; McClish, Allison; Morlock, Emily A.; Sochor, Victoria R.; Stanton, Brittney; Veysey-White, Isaac C.; Revie, Dennis; Jimenez, Luis A.; Palomino, Jennifer J.; Patao, Melissa D.; Patao, Shane M.; Himelblau, Edward T.; Campbell, Jaclyn D.; Hertz, Alexandra L.; McEvilly, Maddison F.; Wagner, Allison R.; Youngblom, James; Bedi, Baljit; Bettincourt, Jeffery; Duso, Erin; Her, Maiye; Hilton, William; House, Samantha; Karimi, Masud; Kumimoto, Kevin; Lee, Rebekah; Lopez, Darryl; Odisho, George; Prasad, Ricky; Robbins, Holly Lyn; Sandhu, Tanveer; Selfridge, Tracy; Tsukashima, Kara; Yosif, Hani; Kokan, Nighat P.; Britt, Latia; Zoellner, Alycia; Spana, Eric P.; Chlebina, Ben T.; Chong, Insun; Friedman, Harrison; Mammo, Danny A.; Ng, Chun L.; Nikam, Vinayak S.; Schwartz, Nicholas U.; Xu, Thomas Q.; Burg, Martin G.; Batten, Spencer M.; Corbeill, Lindsay M.; Enoch, Erica; Ensign, Jesse J.; Franks, Mary E.; Haiker, Breanna; Ingles, Judith A.; Kirkland, Lyndsay D.; Lorenz-Guertin, Joshua M.; Matthews, Jordan; Mittig, Cody M.; Monsma, Nicholaus; Olson, Katherine J.; Perez-Aragon, Guillermo; Ramic, Alen; Ramirez, Jordan R.; Scheiber, Christopher; Schneider, Patrick A.; Schultz, Devon E.; Simon, Matthew; Spencer, Eric; Wernette, Adam C.; Wykle, Maxine E.; Zavala-Arellano, Elizabeth; McDonald, Mitchell J.; Ostby, Kristine; Wendland, Peter; DiAngelo, Justin R.; Ceasrine, Alexis M.; Cox, Amanda H.; Docherty, James E.B.; Gingras, Robert M.; Grieb, Stephanie M.; Pavia, Michael J.; Personius, Casey L.; Polak, Grzegorz L.; Beach, Dale L.; Cerritos, Heaven L.; Horansky, Edward A.; Sharif, Karim A.; Moran, Ryan; Parrish, Susan; Bickford, Kirsten; Bland, Jennifer; Broussard, Juliana; Campbell, Kerry; Deibel, Katelynn E.; Forka, Richard; Lemke, Monika C.; Nelson, Marlee B.; O'Keeffe, Catherine; Ramey, S. Mariel; Schmidt, Luke; Villegas, Paola; Jones, Christopher J.; Christ, Stephanie L.; Mamari, Sami; Rinaldi, Adam S.; Stity, Ghazal; Hark, Amy T.; Scheuerman, Mark; Silver Key, S. Catherine; McRae, Briana D.; Haberman, Adam S.; Asinof, Sam; Carrington, Harriette; Drumm, Kelly; Embry, Terrance; McGuire, Richard; Miller-Foreman, Drew; Rosen, Stella; Safa, Nadia; Schultz, Darrin; Segal, Matt; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Skuse, Gary; Paetkau, Don W.; Bridgman, Rachael K.; Brown, Charlotte M.; Carroll, Alicia R.; Gifford, Francesca M.; Gillespie, Julie Beth; Herman, Susan E.; Holtcamp, Krystal L.; Host, Misha A.; Hussey, Gabrielle; Kramer, Danielle M.; Lawrence, Joan Q.; Martin, Madeline M.; Niemiec, Ellen N.; O'Reilly, Ashleigh P.; Pahl, Olivia A.; Quintana, Guadalupe; Rettie, Elizabeth A.S.; Richardson, Torie L.; Rodriguez, Arianne E.; Rodriguez, Mona O.; Schiraldi, Laura; Smith, Joanna J.; Sugrue, Kelsey F.; Suriano, Lindsey J.; Takach, Kaitlyn E.; Vasquez, Arielle M.; Velez, Ximena; Villafuerte, Elizabeth J.; Vives, Laura T.; Zellmer, Victoria R.; Hauke, Jeanette; Hauser, Charles R.; Barker, Karolyn; Cannon, Laurie; Parsamian, Perouza; Parsons, Samantha; Wichman, Zachariah; Bazinet, Christopher W.; Johnson, Diana E.; Bangura, Abubakarr; Black, Jordan A.; Chevee, Victoria; Einsteen, Sarah A.; Hilton, Sarah K.; Kollmer, Max; Nadendla, Rahul; Stamm, Joyce; Fafara-Thompson, Antoinette E.; Gygi, Amber M.; Ogawa, Emmy E.; Van Camp, Matt; Kocsisova, Zuzana; Leatherman, Judith L.; Modahl, Cassie M.; Rubin, Michael R.; Apiz-Saab, Susana S.; Arias-Mejias, Suzette M.; Carrion-Ortiz, Carlos F.; Claudio-Vazquez, Patricia N.; Espada-Green, Debbie M.; Feliciano-Camacho, Marium; Gonzalez-Bonilla, Karina M.; Taboas-Arroyo, Mariela; Vargas-Franco, Dorianmarie; Montañez-Gonzalez, Raquel; Perez-Otero, Joseph; Rivera-Burgos, Myrielis; Rivera-Rosario, Francisco J.; Eisler, Heather L.; Alexander, Jackie; Begley, Samatha K.; Gabbard, Deana; Allen, Robert J.; Aung, Wint Yan; Barshop, William D.; Boozalis, Amanda; Chu, Vanessa P.; Davis, Jeremy S.; Duggal, Ryan N.; Franklin, Robert; Gavinski, Katherine; Gebreyesus, Heran; Gong, Henry Z.; Greenstein, Rachel A.; Guo, Averill D.; Hanson, Casey; Homa, Kaitlin E.; Hsu, Simon C.; Huang, Yi; Huo, Lucy; Jacobs, Sarah; Jia, Sasha; Jung, Kyle L.; Wai-Chee Kong, Sarah; Kroll, Matthew R.; Lee, Brandon M.; Lee, Paul F.; Levine, Kevin M.; Li, Amy S.; Liu, Chengyu; Liu, Max Mian; Lousararian, Adam P.; Lowery, Peter B.; Mallya, Allyson P.; Marcus, Joseph E.; Ng, Patrick C.; Nguyen, Hien P.; Patel, Ruchik; Precht, Hashini; Rastogi, Suchita; Sarezky, Jonathan M.; Schefkind, Adam; Schultz, Michael B.; Shen, Delia; Skorupa, Tara; Spies, Nicholas C.; Stancu, Gabriel; Vivian Tsang, Hiu Man; Turski, Alice L.; Venkat, Rohit; Waldman, Leah E.; Wang, Kaidi; Wang, Tracy; Wei, Jeffrey W.; Wu, Dennis Y.; Xiong, David D.; Yu, Jack; Zhou, Karen; McNeil, Gerard P.; Fernandez, Robert W.; Menzies, Patrick Gomez; Gu, Tingting; Buhler, Jeremy; Mardis, Elaine R.; Elgin, Sarah C.R.

    2017-01-01

    The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb) in D. ananassae. To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae. Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5′ ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains. PMID:28667019

  3. Cytogenetic mapping of the Muller F element genes in Drosophila willistoni group.

    Science.gov (United States)

    Pita, Sebastián; Panzera, Yanina; Lúcia da Silva Valente, Vera; de Melo, Zilpa das Graças Silva; Garcia, Carolina; Garcia, Ana Cristina Lauer; Montes, Martín Alejandro; Rohde, Claudia

    2014-10-01

    Comparative genomics in Drosophila began in 1940, when Muller stated that the ancestral haploid karyotype of this genus is constituted by five acrocentric chromosomes and one dot chromosome, named A to F elements. In some species of the willistoni group such as Drosophila willistoni and D. insularis, the F element, instead of a dot chromosome, has been incorporated into the E element, forming chromosome III (E + F fusion). The aim of this study was to investigate the scope of the E + F fusion in the willistoni group, evaluating six other species. Fluorescent in situ hybridization was used to locate two genes of the F element previously studied-cubitus interruptus (ci) and eyeless (ey)-in species of the willistoni and bocainensis subgroups. Moreover, polytene chromosome photomaps corresponding to the F element (basal portion of chromosome III) were constructed for each species studied. In D. willistoni, D. paulistorum and D. equinoxialis, the ci gene was located in subSectction 78B and the ey gene in 78C. In D. tropicalis, ci was located in subSection 76B and ey in 76C. In species of the bocainensis subgroup, ci and ey were localized, respectively, at subsections 76B and 76C in D. nebulosa and D. capricorni, and 76A and 76C in D. fumipennis. Despite the differences in the subsection numbers, all species showed the same position for ci and ey. The results confirm the synteny of E + F fusion in willistoni and bocainensis subgroups, and allow estimating the occurrence of this event at 15 Mya, at least.

  4. High-Speed Soft-Decision Decoding of Two Reed-Muller Codes

    Science.gov (United States)

    Lin, Shu; Uehara, Gregory T.

    1996-01-01

    In his research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RNI subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second (Mbps). The combination of a large number of states and a hi ch data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high-speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating and present some of the key architectural approaches being used to

  5. on the Population Growth of the Cladoceran Ceriodaphnia quadrangula (O. F. Muller, 1785.

    Directory of Open Access Journals (Sweden)

    Sevgi Savaş

    2015-12-01

    Full Text Available Cladoceran Ceriodaphnia quadrangula (O.F. Muller, 1785’nın populasyon artışı üzerine sıcaklık ve besin (Scenedesmus acuminatus (von Lagerheim R. H. Chodat yoğunluğunun etkisi. Bu çalışmada, Ceriodaphnia quadrangula’nın populasyon artışı üzerine sıcaklık (20, 25 ve 30 ºC ve farklı besin (Scenedesmus acuminatus yoğunluğunun (15,30,45, 60 ve75x104 h/ml etkisi incelenmiştir. Deneme 16 aydınlık:8 saat karanlık ışık uygulamasında gerçekleştirilmiştir. Deneme başında, farklı besin yoğunlukları içeren her bir tüpe 1 adet 24 saatten genç birey konulmuş, birey sayısı ve büyüme hızı 25 gün süre ile belirlenmiştir. En yüksek birey sayısı (21,433±0,750 birey/ml ve büyüme hızı (0,240±0,004 25 ºC’de 45x104 h/ml’de belirlenmiştir. Besin yoğunluğunun artması, Ceriodaphnia quadrangula’nın birey sayısı ve büyüme hızını arttırmıştır. Farklı besin yoğunluklarının birey sayısına etkisi istatistiki olarak önemli (P0,05 olduğu bulunmuştur

  6. Studies on the Edible Terrestrial Snails Helix aspersa Muller Food Conversion Ratio in a Confined Microclimate System

    Directory of Open Access Journals (Sweden)

    Adrian Toader-Williams

    2010-05-01

    Full Text Available Terrestrial edible snail breeding is an agricultural activity that finds itself at pioneering stage in Romania. One of the species used in snail farming is Helix aspersa Muller. In order to accelerate their growth, farmers feed the snails with pumpkins as well as concentrated forage consisting of mix of flours to which calcium carbonate is added in order to supplement snails need for shell’s development. In a controlled microclimate environment we measured the average growth of six weeks old Helix aspersa Muller snails placed in four different plastic enclosures. The consumption of different type of foods within 24 hours period was measured. The wheat (60%, corn flour (20% and calcium carbonate (20% mix had a superior food conversion ratio (FCR of 4.80, whereas the second FCR registered 6.04 in the case of 53% pumpkin and 47% flour mix served in the same time followed by the pure fresh vegetable mix accounting for a FCR of 8.00 and by 19.02 when only the pumpkin has been administrated as meal. During the experiments the snails did not have access to soil, being known that soil is an integral part of their diet.

  7. Some fossil species of Babylonia seen in ultraviolet light, with description of a new species (Mollusca, Gastropoda)

    NARCIS (Netherlands)

    Regteren, van C.O.; Gittenberger, E.

    1972-01-01

    When preparing a revision of the genus Babylonia for "Indo-Pacific Mollusca", edited by Dr. R. Tucker Abbott, we tried ultraviolet light to see the outline of the colour-pattern of some fossil species. Later on we saw the same method described by Mrs. Katherine Krueger (1971). Dr. H. E. Coomans of

  8. The mitochondrial genome of the sipunculid Phascolopsis gouldii supports its association with Annelida rather than Mollusca

    Energy Technology Data Exchange (ETDEWEB)

    Boore, Jeffrey L.; Staton, Joseph

    2001-09-01

    We have determined the sequence of about half (7470 nts) of the mitochondrial genome of the sipunculid Phascolopsis gouldii, the first representative of this phylum to be so studied. All of the 19 identified genes are transcribed from the same DNA strand. The arrangement of these genes is remarkably similar to that of the oligochaete annelid Lumbricus terrestris. Comparison of both the inferred amino acid sequences and the gene arrangements of a variety of diverse metazoan taxa reveals that the phylum Sipuncula is more closely related to Annelida than to Mollusca. This requires reinterpretation of the homology of several embryological features and of patterns of animal body plan evolution.

  9. Isolation of probiotic bacteria from the hybrid South American catfish Pseudoplatystoma reticulatum × Pseudoplatystoma corruscans (Siluriformes: Pimelodidae: A haematological approach

    Directory of Open Access Journals (Sweden)

    José Luiz Pedreira Mouriño

    2016-05-01

    Full Text Available This study investigated bacterial strains with probiotic potential isolated from the middle portion of healthy hybrid surubim catfish foregut (Pseudoplatystoma reticulatum female × P. corruscans male. Twenty surubims weighing 1.5 ± 0.3 kg were used for bacterial isolation. In total, 41 strains of bacteria were selected in vitro. Ten strains had inhibition zones >10 mm against Aeromonas hydrophila. Five of those strains presented inhibition zones > 9 mm against other pathogenic bacteria and reached concentrations greater than 105 CFU mL−1 in tubes containing de Man, Rogosa and Sharpe (MRS medium. In particular, Weissella cibaria (P36 reached 106 CFU mL−1 in MRS and was able to reduce the pH of the medium to 3.85. In the in vivo intestinal colonization studies, 72 healthy hybrid surubims were fed with a commercial diet supplemented with probiotic W. cibaria for 15 days. Changes in gut community composition were then analyzed, and probiotic profile of W. cibaria was determined molecularly by amplification of rRNA 16S gene was performed using PCR. Compared to control fish, W. cibaria-supplemented fish showed an increase in RBC. These results show the efficacy of our haematological approach to probiotic screening in hybrid sorubim.

  10. Drosophila Muller F Elements Maintain a Distinct Set of Genomic Properties Over 40 Million Years of Evolution

    Science.gov (United States)

    Leung, Wilson; Shaffer, Christopher D.; Reed, Laura K.; Smith, Sheryl T.; Barshop, William; Dirkes, William; Dothager, Matthew; Lee, Paul; Wong, Jeannette; Xiong, David; Yuan, Han; Bedard, James E. J.; Machone, Joshua F.; Patterson, Seantay D.; Price, Amber L.; Turner, Bryce A.; Robic, Srebrenka; Luippold, Erin K.; McCartha, Shannon R.; Walji, Tezin A.; Walker, Chelsea A.; Saville, Kenneth; Abrams, Marita K.; Armstrong, Andrew R.; Armstrong, William; Bailey, Robert J.; Barberi, Chelsea R.; Beck, Lauren R.; Blaker, Amanda L.; Blunden, Christopher E.; Brand, Jordan P.; Brock, Ethan J.; Brooks, Dana W.; Brown, Marie; Butzler, Sarah C.; Clark, Eric M.; Clark, Nicole B.; Collins, Ashley A.; Cotteleer, Rebecca J.; Cullimore, Peterson R.; Dawson, Seth G.; Docking, Carter T.; Dorsett, Sasha L.; Dougherty, Grace A.; Downey, Kaitlyn A.; Drake, Andrew P.; Earl, Erica K.; Floyd, Trevor G.; Forsyth, Joshua D.; Foust, Jonathan D.; Franchi, Spencer L.; Geary, James F.; Hanson, Cynthia K.; Harding, Taylor S.; Harris, Cameron B.; Heckman, Jonathan M.; Holderness, Heather L.; Howey, Nicole A.; Jacobs, Dontae A.; Jewell, Elizabeth S.; Kaisler, Maria; Karaska, Elizabeth A.; Kehoe, James L.; Koaches, Hannah C.; Koehler, Jessica; Koenig, Dana; Kujawski, Alexander J.; Kus, Jordan E.; Lammers, Jennifer A.; Leads, Rachel R.; Leatherman, Emily C.; Lippert, Rachel N.; Messenger, Gregory S.; Morrow, Adam T.; Newcomb, Victoria; Plasman, Haley J.; Potocny, Stephanie J.; Powers, Michelle K.; Reem, Rachel M.; Rennhack, Jonathan P.; Reynolds, Katherine R.; Reynolds, Lyndsey A.; Rhee, Dong K.; Rivard, Allyson B.; Ronk, Adam J.; Rooney, Meghan B.; Rubin, Lainey S.; Salbert, Luke R.; Saluja, Rasleen K.; Schauder, Taylor; Schneiter, Allison R.; Schulz, Robert W.; Smith, Karl E.; Spencer, Sarah; Swanson, Bryant R.; Tache, Melissa A.; Tewilliager, Ashley A.; Tilot, Amanda K.; VanEck, Eve; Villerot, Matthew M.; Vylonis, Megan B.; Watson, David T.; Wurzler, Juliana A.; Wysocki, Lauren M.; Yalamanchili, Monica; Zaborowicz, Matthew A.; Emerson, Julia A.; Ortiz, Carlos; Deuschle, Frederic J.; DiLorenzo, Lauren A.; Goeller, Katie L.; Macchi, Christopher R.; Muller, Sarah E.; Pasierb, Brittany D.; Sable, Joseph E.; Tucci, Jessica M.; Tynon, Marykathryn; Dunbar, David A.; Beken, Levent H.; Conturso, Alaina C.; Danner, Benjamin L.; DeMichele, Gabriella A.; Gonzales, Justin A.; Hammond, Maureen S.; Kelley, Colleen V.; Kelly, Elisabeth A.; Kulich, Danielle; Mageeney, Catherine M.; McCabe, Nikie L.; Newman, Alyssa M.; Spaeder, Lindsay A.; Tumminello, Richard A.; Revie, Dennis; Benson, Jonathon M.; Cristostomo, Michael C.; DaSilva, Paolo A.; Harker, Katherine S.; Jarrell, Jenifer N.; Jimenez, Luis A.; Katz, Brandon M.; Kennedy, William R.; Kolibas, Kimberly S.; LeBlanc, Mark T.; Nguyen, Trung T.; Nicolas, Daniel S.; Patao, Melissa D.; Patao, Shane M.; Rupley, Bryan J.; Sessions, Bridget J.; Weaver, Jennifer A.; Goodman, Anya L.; Alvendia, Erica L.; Baldassari, Shana M.; Brown, Ashley S.; Chase, Ian O.; Chen, Maida; Chiang, Scott; Cromwell, Avery B.; Custer, Ashley F.; DiTommaso, Tia M.; El-Adaimi, Jad; Goscinski, Nora C.; Grove, Ryan A.; Gutierrez, Nestor; Harnoto, Raechel S.; Hedeen, Heather; Hong, Emily L.; Hopkins, Barbara L.; Huerta, Vilma F.; Khoshabian, Colin; LaForge, Kristin M.; Lee, Cassidy T.; Lewis, Benjamin M.; Lydon, Anniken M.; Maniaci, Brian J.; Mitchell, Ryan D.; Morlock, Elaine V.; Morris, William M.; Naik, Priyanka; Olson, Nicole C.; Osterloh, Jeannette M.; Perez, Marcos A.; Presley, Jonathan D.; Randazzo, Matt J.; Regan, Melanie K.; Rossi, Franca G.; Smith, Melanie A.; Soliterman, Eugenia A.; Sparks, Ciani J.; Tran, Danny L.; Wan, Tiffany; Welker, Anne A.; Wong, Jeremy N.; Sreenivasan, Aparna; Youngblom, Jim; Adams, Andrew; Alldredge, Justin; Bryant, Ashley; Carranza, David; Cifelli, Alyssa; Coulson, Kevin; Debow, Calise; Delacruz, Noelle; Emerson, Charlene; Farrar, Cassandra; Foret, Don; Garibay, Edgar; Gooch, John; Heslop, Michelle; Kaur, Sukhjit; Khan, Ambreen; Kim, Van; Lamb, Travis; Lindbeck, Peter; Lucas, Gabi; Macias, Elizabeth; Martiniuc, Daniela; Mayorga, Lissett; Medina, Joseph; Membreno, Nelson; Messiah, Shady; Neufeld, Lacey; Nguyen, San Francisco; Nichols, Zachary; Odisho, George; Peterson, Daymon; Rodela, Laura; Rodriguez, Priscilla; Rodriguez, Vanessa; Ruiz, Jorge; Sherrill, Will; Silva, Valeria; Sparks, Jeri; Statton, Geeta; Townsend, Ashley; Valdez, Isabel; Waters, Mary; Westphal, Kyle; Winkler, Stacey; Zumkehr, Joannee; DeJong, Randall J.; Hoogewerf, Arlene J.; Ackerman, Cheri M.; Armistead, Isaac O.; Baatenburg, Lara; Borr, Matthew J.; Brouwer, Lindsay K.; Burkhart, Brandon J.; Bushhouse, Kelsey T.; Cesko, Lejla; Choi, Tiffany Y. Y.; Cohen, Heather; Damsteegt, Amanda M.; Darusz, Jess M.; Dauphin, Cory M.; Davis, Yelena P.; Diekema, Emily J.; Drewry, Melissa; Eisen, Michelle E. M.; Faber, Hayley M.; Faber, Katherine J.; Feenstra, Elizabeth; Felzer-Kim, Isabella T.; Hammond, Brandy L.; Hendriksma, Jesse; Herrold, Milton R.; Hilbrands, Julia A.; Howell, Emily J.; Jelgerhuis, Sarah A.; Jelsema, Timothy R.; Johnson, Benjamin K.; Jones, Kelly K.; Kim, Anna; Kooienga, Ross D.; Menyes, Erika E.; Nollet, Eric A.; Plescher, Brittany E.; Rios, Lindsay; Rose, Jenny L.; Schepers, Allison J.; Scott, Geoff; Smith, Joshua R.; Sterling, Allison M.; Tenney, Jenna C.; Uitvlugt, Chris; VanDyken, Rachel E.; VanderVennen, Marielle; Vue, Samantha; Kokan, Nighat P.; Agbley, Kwabea; Boham, Sampson K.; Broomfield, Daniel; Chapman, Kayla; Dobbe, Ali; Dobbe, Ian; Harrington, William; Ibrahem, Marwan; Kennedy, Andre; Koplinsky, Chad A.; Kubricky, Cassandra; Ladzekpo, Danielle; Pattison, Claire; Ramirez, Roman E.; Wande, Lucia; Woehlke, Sarah; Wawersik, Matthew; Kiernan, Elizabeth; Thompson, Jeffrey S.; Banker, Roxanne; Bartling, Justina R.; Bhatiya, Chinmoy I.; Boudoures, Anna L.; Christiansen, Lena; Fosselman, Daniel S.; French, Kristin M.; Gill, Ishwar S.; Havill, Jessen T.; Johnson, Jaelyn L.; Keny, Lauren J.; Kerber, John M.; Klett, Bethany M.; Kufel, Christina N.; May, Francis J.; Mecoli, Jonathan P.; Merry, Callie R.; Meyer, Lauren R.; Miller, Emily G.; Mullen, Gregory J.; Palozola, Katherine C.; Pfeil, Jacob J.; Thomas, Jessica G.; Verbofsky, Evan M.; Spana, Eric P.; Agarwalla, Anant; Chapman, Julia; Chlebina, Ben; Chong, Insun; Falk, I.N.; Fitzgibbons, John D.; Friedman, Harrison; Ighile, Osagie; Kim, Andrew J.; Knouse, Kristin A.; Kung, Faith; Mammo, Danny; Ng, Chun Leung; Nikam, Vinayak S.; Norton, Diana; Pham, Philip; Polk, Jessica W.; Prasad, Shreya; Rankin, Helen; Ratliff, Camille D.; Scala, Victoria; Schwartz, Nicholas U.; Shuen, Jessica A.; Xu, Amy; Xu, Thomas Q.; Zhang, Yi; Rosenwald, Anne G.; Burg, Martin G.; Adams, Stephanie J.; Baker, Morgan; Botsford, Bobbi; Brinkley, Briana; Brown, Carter; Emiah, Shadie; Enoch, Erica; Gier, Chad; Greenwell, Alyson; Hoogenboom, Lindsay; Matthews, Jordan E.; McDonald, Mitchell; Mercer, Amanda; Monsma, Nicholaus; Ostby, Kristine; Ramic, Alen; Shallman, Devon; Simon, Matthew; Spencer, Eric; Tomkins, Trisha; Wendland, Pete; Wylie, Anna; Wolyniak, Michael J.; Robertson, Gregory M.; Smith, Samuel I.; DiAngelo, Justin R.; Sassu, Eric D.; Bhalla, Satish C.; Sharif, Karim A.; Choeying, Tenzin; Macias, Jason S.; Sanusi, Fareed; Torchon, Karvyn; Bednarski, April E.; Alvarez, Consuelo J.; Davis, Kristen C.; Dunham, Carrie A.; Grantham, Alaina J.; Hare, Amber N.; Schottler, Jennifer; Scott, Zackary W.; Kuleck, Gary A.; Yu, Nicole S.; Kaehler, Marian M.; Jipp, Jacob; Overvoorde, Paul J.; Shoop, Elizabeth; Cyrankowski, Olivia; Hoover, Betsy; Kusner, Matt; Lin, Devry; Martinov, Tijana; Misch, Jonathan; Salzman, Garrett; Schiedermayer, Holly; Snavely, Michael; Zarrasola, Stephanie; Parrish, Susan; Baker, Atlee; Beckett, Alissa; Belella, Carissa; Bryant, Julie; Conrad, Turner; Fearnow, Adam; Gomez, Carolina; Herbstsomer, Robert A.; Hirsch, Sarah; Johnson, Christen; Jones, Melissa; Kabaso, Rita; Lemmon, Eric; Vieira, Carolina Marques dos Santos; McFarland, Darryl; McLaughlin, Christopher; Morgan, Abbie; Musokotwane, Sepo; Neutzling, William; Nietmann, Jana; Paluskievicz, Christina; Penn, Jessica; Peoples, Emily; Pozmanter, Caitlin; Reed, Emily; Rigby, Nichole; Schmidt, Lasse; Shelton, Micah; Shuford, Rebecca; Tirasawasdichai, Tiara; Undem, Blair; Urick, Damian; Vondy, Kayla; Yarrington, Bryan; Eckdahl, Todd T.; Poet, Jeffrey L.; Allen, Alica B.; Anderson, John E.; Barnett, Jason M.; Baumgardner, Jordan S.; Brown, Adam D.; Carney, Jordan E.; Chavez, Ramiro A.; Christgen, Shelbi L.; Christie, Jordan S.; Clary, Andrea N.; Conn, Michel A.; Cooper, Kristen M.; Crowley, Matt J.; Crowley, Samuel T.; Doty, Jennifer S.; Dow, Brian A.; Edwards, Curtis R.; Elder, Darcie D.; Fanning, John P.; Janssen, Bridget M.; Lambright, Anthony K.; Lane, Curtiss E.; Limle, Austin B.; Mazur, Tammy; McCracken, Marly R.; McDonough, Alexa M.; Melton, Amy D.; Minnick, Phillip J.; Musick, Adam E.; Newhart, William H.; Noynaert, Joseph W.; Ogden, Bradley J.; Sandusky, Michael W.; Schmuecker, Samantha M.; Shipman, Anna L.; Smith, Anna L.; Thomsen, Kristen M.; Unzicker, Matthew R.; Vernon, William B.; Winn, Wesley W.; Woyski, Dustin S.; Zhu, Xiao; Du, Chunguang; Ament, Caitlin; Aso, Soham; Bisogno, Laura Simone; Caronna, Jason; Fefelova, Nadezhda; Lopez, Lenin; Malkowitz, Lorraine; Marra, Jonathan; Menillo, Daniella; Obiorah, Ifeanyi; Onsarigo, Eric Nyabeta; Primus, Shekerah; Soos, Mahdi; Tare, Archana; Zidan, Ameer; Jones, Christopher J.; Aronhalt, Todd; Bellush, James M.; Burke, Christa; DeFazio, Steve; Does, Benjamin R.; Johnson, Todd D.; Keysock, Nicholas; Knudsen, Nelson H.; Messler, James; Myirski, Kevin; Rekai, Jade Lea; Rempe, Ryan Michael; Salgado, Michael S.; Stagaard, Erica; Starcher, Justin R.; Waggoner, Andrew W.; Yemelyanova, Anastasia K.; Hark, Amy T.; Bertolet, Anne; Kuschner, Cyrus E.; Parry, Kesley; Quach, Michael; Shantzer, Lindsey; Shaw, Mary E.; Smith, Mary A.; Glenn, Omolara; Mason, Portia; Williams, Charlotte; Key, S. Catherine Silver; Henry, Tyneshia C. P.; Johnson, Ashlee G.; White, Jackie X.; Haberman, Adam; Asinof, Sam; Drumm, Kelly; Freeburg, Trip; Safa, Nadia; Schultz, Darrin; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Wellinghoff, Jules; Hoopes, Laura L. M.; Chau, Kim M.; Ward, Alyssa; Regisford, E. Gloria C.; Augustine, LaJerald; Davis-Reyes, Brionna; Echendu, Vivienne; Hales, Jasmine; Ibarra, Sharon; Johnson, Lauriaun; Ovu, Steven; Braverman, John M.; Bahr, Thomas J.; Caesar, Nicole M.; Campana, Christopher; Cassidy, Daniel W.; Cognetti, Peter A.; English, Johnathan D.; Fadus, Matthew C.; Fick, Cameron N.; Freda, Philip J.; Hennessy, Bryan M.; Hockenberger, Kelsey; Jones, Jennifer K.; King, Jessica E.; Knob, Christopher R.; Kraftmann, Karen J.; Li, Linghui; Lupey, Lena N.; Minniti, Carl J.; Minton, Thomas F.; Moran, Joseph V.; Mudumbi, Krishna; Nordman, Elizabeth C.; Puetz, William J.; Robinson, Lauren M.; Rose, Thomas J.; Sweeney, Edward P.; Timko, Ashley S.; Paetkau, Don W.; Eisler, Heather L.; Aldrup, Megan E.; Bodenberg, Jessica M.; Cole, Mara G.; Deranek, Kelly M.; DeShetler, Megan; Dowd, Rose M.; Eckardt, Alexandra K.; Ehret, Sharon C.; Fese, Jessica; Garrett, Amanda D.; Kammrath, Anna; Kappes, Michelle L.; Light, Morgan R.; Meier, Anne C.; O’Rouke, Allison; Perella, Mallory; Ramsey, Kimberley; Ramthun, Jennifer R.; Reilly, Mary T.; Robinett, Deirdre; Rossi, Nadine L.; Schueler, Mary Grace; Shoemaker, Emma; Starkey, Kristin M.; Vetor, Ashley; Vrable, Abby; Chandrasekaran, Vidya; Beck, Christopher; Hatfield, Kristen R.; Herrick, Douglas A.; Khoury, Christopher B.; Lea, Charlotte; Louie, Christopher A.; Lowell, Shannon M.; Reynolds, Thomas J.; Schibler, Jeanine; Scoma, Alexandra H.; Smith-Gee, Maxwell T.; Tuberty, Sarah; Smith, Christopher D.; Lopilato, Jane E.; Hauke, Jeanette; Roecklein-Canfield, Jennifer A.; Corrielus, Maureen; Gilman, Hannah; Intriago, Stephanie; Maffa, Amanda; Rauf, Sabya A.; Thistle, Katrina; Trieu, Melissa; Winters, Jenifer; Yang, Bib; Hauser, Charles R.; Abusheikh, Tariq; Ashrawi, Yara; Benitez, Pedro; Boudreaux, Lauren R.; Bourland, Megan; Chavez, Miranda; Cruz, Samantha; Elliott, GiNell; Farek, Jesse R.; Flohr, Sarah; Flores, Amanda H.; Friedrichs, Chelsey; Fusco, Zach; Goodwin, Zane; Helmreich, Eric; Kiley, John; Knepper, John Mark; Langner, Christine; Martinez, Megan; Mendoza, Carlos; Naik, Monal; Ochoa, Andrea; Ragland, Nicolas; Raimey, England; Rathore, Sunil; Reza, Evangelina; Sadovsky, Griffin; Seydoux, Marie-Isabelle B.; Smith, Jonathan E.; Unruh, Anna K.; Velasquez, Vicente; Wolski, Matthew W.; Gosser, Yuying; Govind, Shubha; Clarke-Medley, Nicole; Guadron, Leslie; Lau, Dawn; Lu, Alvin; Mazzeo, Cheryl; Meghdari, Mariam; Ng, Simon; Pamnani, Brad; Plante, Olivia; Shum, Yuki Kwan Wa; Song, Roy; Johnson, Diana E.; Abdelnabi, Mai; Archambault, Alexi; Chamma, Norma; Gaur, Shailly; Hammett, Deborah; Kandahari, Adrese; Khayrullina, Guzal; Kumar, Sonali; Lawrence, Samantha; Madden, Nigel; Mandelbaum, Max; Milnthorp, Heather; Mohini, Shiv; Patel, Roshni; Peacock, Sarah J.; Perling, Emily; Quintana, Amber; Rahimi, Michael; Ramirez, Kristen; Singhal, Rishi; Weeks, Corinne; Wong, Tiffany; Gillis, Aubree T.; Moore, Zachary D.; Savell, Christopher D.; Watson, Reece; Mel, Stephanie F.; Anilkumar, Arjun A.; Bilinski, Paul; Castillo, Rostislav; Closser, Michael; Cruz, Nathalia M.; Dai, Tiffany; Garbagnati, Giancarlo F.; Horton, Lanor S.; Kim, Dongyeon; Lau, Joyce H.; Liu, James Z.; Mach, Sandy D.; Phan, Thu A.; Ren, Yi; Stapleton, Kenneth E.; Strelitz, Jean M.; Sunjed, Ray; Stamm, Joyce; Anderson, Morgan C.; Bonifield, Bethany Grace; Coomes, Daniel; Dillman, Adam; Durchholz, Elaine J.; Fafara-Thompson, Antoinette E.; Gross, Meleah J.; Gygi, Amber M.; Jackson, Lesley E.; Johnson, Amy; Kocsisova, Zuzana; Manghelli, Joshua L.; McNeil, Kylie; Murillo, Michael; Naylor, Kierstin L.; Neely, Jessica; Ogawa, Emmy E.; Rich, Ashley; Rogers, Anna; Spencer, J. Devin; Stemler, Kristina M.; Throm, Allison A.; Van Camp, Matt; Weihbrecht, Katie; Wiles, T. Aaron; Williams, Mallory A.; Williams, Matthew; Zoll, Kyle; Bailey, Cheryl; Zhou, Leming; Balthaser, Darla M.; Bashiri, Azita; Bower, Mindy E.; Florian, Kayla A.; Ghavam, Nazanin; Greiner-Sosanko, Elizabeth S.; Karim, Helmet; Mullen, Victor W.; Pelchen, Carly E.; Yenerall, Paul M.; Zhang, Jiayu; Rubin, Michael R.; Arias-Mejias, Suzette M.; Bermudez-Capo, Armando G.; Bernal-Vega, Gabriela V.; Colon-Vazquez, Mariela; Flores-Vazquez, Arelys; Gines-Rosario, Mariela; Llavona-Cartagena, Ivan G.; Martinez-Rodriguez, Javier O.; Ortiz-Fuentes, Lionel; Perez-Colomba, Eliezer O.; Perez-Otero, Joseph; Rivera, Elisandra; Rodriguez-Giron, Luke J.; Santiago-Sanabria, Arnaldo J.; Senquiz-Gonzalez, Andrea M.; delValle, Frank R. Soto; Vargas-Franco, Dorianmarie; Velázquez-Soto, Karla I.; Zambrana-Burgos, Joan D.; Martinez-Cruzado, Juan Carlos; Asencio-Zayas, Lillyann; Babilonia-Figueroa, Kevin; Beauchamp-Pérez, Francis D.; Belén-Rodríguez, Juliana; Bracero-Quiñones, Luciann; Burgos-Bula, Andrea P.; Collado-Méndez, Xavier A.; Colón-Cruz, Luis R.; Correa-Muller, Ana I.; Crooke-Rosado, Jonathan L.; Cruz-García, José M.; Defendini-Ávila, Marianna; Delgado-Peraza, Francheska M.; Feliciano-Cancela, Alex J.; Gónzalez-Pérez, Valerie M.; Guiblet, Wilfried; Heredia-Negrón, Aldo; Hernández-Muñiz, Jennifer; Irizarry-González, Lourdes N.; Laboy-Corales, Ángel L.; Llaurador-Caraballo, Gabriela A.; Marín-Maldonado, Frances; Marrero-Llerena, Ulises; Martell-Martínez, Héctor A.; Martínez-Traverso, Idaliz M.; Medina-Ortega, Kiara N.; Méndez-Castellanos, Sonya G.; Menéndez-Serrano, Krizia C.; Morales-Caraballo, Carol I.; Ortiz-DeChoudens, Saryleine; Ortiz-Ortiz, Patricia; Pagán-Torres, Hendrick; Pérez-Afanador, Diana; Quintana-Torres, Enid M.; Ramírez-Aponte, Edwin G.; Riascos-Cuero, Carolina; Rivera-Llovet, Michelle S.; Rivera-Pagán, Ingrid T.; Rivera-Vicéns, Ramón E.; Robles-Juarbe, Fabiola; Rodríguez-Bonilla, Lorraine; Rodríguez-Echevarría, Brian O.; Rodríguez-García, Priscila M.; Rodríguez-Laboy, Abneris E.; Rodríguez-Santiago, Susana; Rojas-Vargas, Michael L.; Rubio-Marrero, Eva N.; Santiago-Colón, Albeliz; Santiago-Ortiz, Jorge L.; Santos-Ramos, Carlos E.; Serrano-González, Joseline; Tamayo-Figueroa, Alina M.; Tascón-Peñaranda, Edna P.; Torres-Castillo, José L.; Valentín-Feliciano, Nelson A.; Valentín-Feliciano, Yashira M.; Vargas-Barreto, Nadyan M.; Vélez-Vázquez, Miguel; Vilanova-Vélez, Luis R.; Zambrana-Echevarría, Cristina; MacKinnon, Christy; Chung, Hui-Min; Kay, Chris; Pinto, Anthony; Kopp, Olga R.; Burkhardt, Joshua; Harward, Chris; Allen, Robert; Bhat, Pavan; Chang, Jimmy Hsiang-Chun; Chen, York; Chesley, Christopher; Cohn, Dara; DuPuis, David; Fasano, Michael; Fazzio, Nicholas; Gavinski, Katherine; Gebreyesus, Heran; Giarla, Thomas; Gostelow, Marcus; Greenstein, Rachel; Gunasinghe, Hashini; Hanson, Casey; Hay, Amanda; He, Tao Jian; Homa, Katie; Howe, Ruth; Howenstein, Jeff; Huang, Henry; Khatri, Aaditya; Kim, Young Lu; Knowles, Olivia; Kong, Sarah; Krock, Rebecca; Kroll, Matt; Kuhn, Julia; Kwong, Matthew; Lee, Brandon; Lee, Ryan; Levine, Kevin; Li, Yedda; Liu, Bo; Liu, Lucy; Liu, Max; Lousararian, Adam; Ma, Jimmy; Mallya, Allyson; Manchee, Charlie; Marcus, Joseph; McDaniel, Stephen; Miller, Michelle L.; Molleston, Jerome M.; Diez, Cristina Montero; Ng, Patrick; Ngai, Natalie; Nguyen, Hien; Nylander, Andrew; Pollack, Jason; Rastogi, Suchita; Reddy, Himabindu; Regenold, Nathaniel; Sarezky, Jon; Schultz, Michael; Shim, Jien; Skorupa, Tara; Smith, Kenneth; Spencer, Sarah J.; Srikanth, Priya; Stancu, Gabriel; Stein, Andrew P.; Strother, Marshall; Sudmeier, Lisa; Sun, Mengyang; Sundaram, Varun; Tazudeen, Noor; Tseng, Alan; Tzeng, Albert; Venkat, Rohit; Venkataram, Sandeep; Waldman, Leah; Wang, Tracy; Yang, Hao; Yu, Jack Y.; Zheng, Yin; Preuss, Mary L.; Garcia, Angelica; Juergens, Matt; Morris, Robert W.; Nagengast, Alexis A.; Azarewicz, Julie; Carr, Thomas J.; Chichearo, Nicole; Colgan, Mike; Donegan, Megan; Gardner, Bob; Kolba, Nik; Krumm, Janice L.; Lytle, Stacey; MacMillian, Laurell; Miller, Mary; Montgomery, Andrew; Moretti, Alysha; Offenbacker, Brittney; Polen, Mike; Toth, John; Woytanowski, John; Kadlec, Lisa; Crawford, Justin; Spratt, Mary L.; Adams, Ashley L.; Barnard, Brianna K.; Cheramie, Martin N.; Eime, Anne M.; Golden, Kathryn L.; Hawkins, Allyson P.; Hill, Jessica E.; Kampmeier, Jessica A.; Kern, Cody D.; Magnuson, Emily E.; Miller, Ashley R.; Morrow, Cody M.; Peairs, Julia C.; Pickett, Gentry L.; Popelka, Sarah A.; Scott, Alexis J.; Teepe, Emily J.; TerMeer, Katie A.; Watchinski, Carmen A.; Watson, Lucas A.; Weber, Rachel E.; Woodard, Kate A.; Barnard, Daron C.; Appiah, Isaac; Giddens, Michelle M.; McNeil, Gerard P.; Adebayo, Adeola; Bagaeva, Kate; Chinwong, Justina; Dol, Chrystel; George, Eunice; Haltaufderhyde, Kirk; Haye, Joanna; Kaur, Manpreet; Semon, Max; Serjanov, Dmitri; Toorie, Anika; Wilson, Christopher; Riddle, Nicole C.; Buhler, Jeremy; Mardis, Elaine R.

    2015-01-01

    The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu. PMID:25740935

  11. Drosophila muller f elements maintain a distinct set of genomic properties over 40 million years of evolution.

    Science.gov (United States)

    Leung, Wilson; Shaffer, Christopher D; Reed, Laura K; Smith, Sheryl T; Barshop, William; Dirkes, William; Dothager, Matthew; Lee, Paul; Wong, Jeannette; Xiong, David; Yuan, Han; Bedard, James E J; Machone, Joshua F; Patterson, Seantay D; Price, Amber L; Turner, Bryce A; Robic, Srebrenka; Luippold, Erin K; McCartha, Shannon R; Walji, Tezin A; Walker, Chelsea A; Saville, Kenneth; Abrams, Marita K; Armstrong, Andrew R; Armstrong, William; Bailey, Robert J; Barberi, Chelsea R; Beck, Lauren R; Blaker, Amanda L; Blunden, Christopher E; Brand, Jordan P; Brock, Ethan J; Brooks, Dana W; Brown, Marie; Butzler, Sarah C; Clark, Eric M; Clark, Nicole B; Collins, Ashley A; Cotteleer, Rebecca J; Cullimore, Peterson R; Dawson, Seth G; Docking, Carter T; Dorsett, Sasha L; Dougherty, Grace A; Downey, Kaitlyn A; Drake, Andrew P; Earl, Erica K; Floyd, Trevor G; Forsyth, Joshua D; Foust, Jonathan D; Franchi, Spencer L; Geary, James F; Hanson, Cynthia K; Harding, Taylor S; Harris, Cameron B; Heckman, Jonathan M; Holderness, Heather L; Howey, Nicole A; Jacobs, Dontae A; Jewell, Elizabeth S; Kaisler, Maria; Karaska, Elizabeth A; Kehoe, James L; Koaches, Hannah C; Koehler, Jessica; Koenig, Dana; Kujawski, Alexander J; Kus, Jordan E; Lammers, Jennifer A; Leads, Rachel R; Leatherman, Emily C; Lippert, Rachel N; Messenger, Gregory S; Morrow, Adam T; Newcomb, Victoria; Plasman, Haley J; Potocny, Stephanie J; Powers, Michelle K; Reem, Rachel M; Rennhack, Jonathan P; Reynolds, Katherine R; Reynolds, Lyndsey A; Rhee, Dong K; Rivard, Allyson B; Ronk, Adam J; Rooney, Meghan B; Rubin, Lainey S; Salbert, Luke R; Saluja, Rasleen K; Schauder, Taylor; Schneiter, Allison R; Schulz, Robert W; Smith, Karl E; Spencer, Sarah; Swanson, Bryant R; Tache, Melissa A; Tewilliager, Ashley A; Tilot, Amanda K; VanEck, Eve; Villerot, Matthew M; Vylonis, Megan B; Watson, David T; Wurzler, Juliana A; Wysocki, Lauren M; Yalamanchili, Monica; Zaborowicz, Matthew A; Emerson, Julia A; Ortiz, Carlos; Deuschle, Frederic J; DiLorenzo, Lauren A; Goeller, Katie L; Macchi, Christopher R; Muller, Sarah E; Pasierb, Brittany D; Sable, Joseph E; Tucci, Jessica M; Tynon, Marykathryn; Dunbar, David A; Beken, Levent H; Conturso, Alaina C; Danner, Benjamin L; DeMichele, Gabriella A; Gonzales, Justin A; Hammond, Maureen S; Kelley, Colleen V; Kelly, Elisabeth A; Kulich, Danielle; Mageeney, Catherine M; McCabe, Nikie L; Newman, Alyssa M; Spaeder, Lindsay A; Tumminello, Richard A; Revie, Dennis; Benson, Jonathon M; Cristostomo, Michael C; DaSilva, Paolo A; Harker, Katherine S; Jarrell, Jenifer N; Jimenez, Luis A; Katz, Brandon M; Kennedy, William R; Kolibas, Kimberly S; LeBlanc, Mark T; Nguyen, Trung T; Nicolas, Daniel S; Patao, Melissa D; Patao, Shane M; Rupley, Bryan J; Sessions, Bridget J; Weaver, Jennifer A; Goodman, Anya L; Alvendia, Erica L; Baldassari, Shana M; Brown, Ashley S; Chase, Ian O; Chen, Maida; Chiang, Scott; Cromwell, Avery B; Custer, Ashley F; DiTommaso, Tia M; El-Adaimi, Jad; Goscinski, Nora C; Grove, Ryan A; Gutierrez, Nestor; Harnoto, Raechel S; Hedeen, Heather; Hong, Emily L; Hopkins, Barbara L; Huerta, Vilma F; Khoshabian, Colin; LaForge, Kristin M; Lee, Cassidy T; Lewis, Benjamin M; Lydon, Anniken M; Maniaci, Brian J; Mitchell, Ryan D; Morlock, Elaine V; Morris, William M; Naik, Priyanka; Olson, Nicole C; Osterloh, Jeannette M; Perez, Marcos A; Presley, Jonathan D; Randazzo, Matt J; Regan, Melanie K; Rossi, Franca G; Smith, Melanie A; Soliterman, Eugenia A; Sparks, Ciani J; Tran, Danny L; Wan, Tiffany; Welker, Anne A; Wong, Jeremy N; Sreenivasan, Aparna; Youngblom, Jim; Adams, Andrew; Alldredge, Justin; Bryant, Ashley; Carranza, David; Cifelli, Alyssa; Coulson, Kevin; Debow, Calise; Delacruz, Noelle; Emerson, Charlene; Farrar, Cassandra; Foret, Don; Garibay, Edgar; Gooch, John; Heslop, Michelle; Kaur, Sukhjit; Khan, Ambreen; Kim, Van; Lamb, Travis; Lindbeck, Peter; Lucas, Gabi; Macias, Elizabeth; Martiniuc, Daniela; Mayorga, Lissett; Medina, Joseph; Membreno, Nelson; Messiah, Shady; Neufeld, Lacey; Nguyen, San Francisco; Nichols, Zachary; Odisho, George; Peterson, Daymon; Rodela, Laura; Rodriguez, Priscilla; Rodriguez, Vanessa; Ruiz, Jorge; Sherrill, Will; Silva, Valeria; Sparks, Jeri; Statton, Geeta; Townsend, Ashley; Valdez, Isabel; Waters, Mary; Westphal, Kyle; Winkler, Stacey; Zumkehr, Joannee; DeJong, Randall J; Hoogewerf, Arlene J; Ackerman, Cheri M; Armistead, Isaac O; Baatenburg, Lara; Borr, Matthew J; Brouwer, Lindsay K; Burkhart, Brandon J; Bushhouse, Kelsey T; Cesko, Lejla; Choi, Tiffany Y Y; Cohen, Heather; Damsteegt, Amanda M; Darusz, Jess M; Dauphin, Cory M; Davis, Yelena P; Diekema, Emily J; Drewry, Melissa; Eisen, Michelle E M; Faber, Hayley M; Faber, Katherine J; Feenstra, Elizabeth; Felzer-Kim, Isabella T; Hammond, Brandy L; Hendriksma, Jesse; Herrold, Milton R; Hilbrands, Julia A; Howell, Emily J; Jelgerhuis, Sarah A; Jelsema, Timothy R; Johnson, Benjamin K; Jones, Kelly K; Kim, Anna; Kooienga, Ross D; Menyes, Erika E; Nollet, Eric A; Plescher, Brittany E; Rios, Lindsay; Rose, Jenny L; Schepers, Allison J; Scott, Geoff; Smith, Joshua R; Sterling, Allison M; Tenney, Jenna C; Uitvlugt, Chris; VanDyken, Rachel E; VanderVennen, Marielle; Vue, Samantha; Kokan, Nighat P; Agbley, Kwabea; Boham, Sampson K; Broomfield, Daniel; Chapman, Kayla; Dobbe, Ali; Dobbe, Ian; Harrington, William; Ibrahem, Marwan; Kennedy, Andre; Koplinsky, Chad A; Kubricky, Cassandra; Ladzekpo, Danielle; Pattison, Claire; Ramirez, Roman E; Wande, Lucia; Woehlke, Sarah; Wawersik, Matthew; Kiernan, Elizabeth; Thompson, Jeffrey S; Banker, Roxanne; Bartling, Justina R; Bhatiya, Chinmoy I; Boudoures, Anna L; Christiansen, Lena; Fosselman, Daniel S; French, Kristin M; Gill, Ishwar S; Havill, Jessen T; Johnson, Jaelyn L; Keny, Lauren J; Kerber, John M; Klett, Bethany M; Kufel, Christina N; May, Francis J; Mecoli, Jonathan P; Merry, Callie R; Meyer, Lauren R; Miller, Emily G; Mullen, Gregory J; Palozola, Katherine C; Pfeil, Jacob J; Thomas, Jessica G; Verbofsky, Evan M; Spana, Eric P; Agarwalla, Anant; Chapman, Julia; Chlebina, Ben; Chong, Insun; Falk, I N; Fitzgibbons, John D; Friedman, Harrison; Ighile, Osagie; Kim, Andrew J; Knouse, Kristin A; Kung, Faith; Mammo, Danny; Ng, Chun Leung; Nikam, Vinayak S; Norton, Diana; Pham, Philip; Polk, Jessica W; Prasad, Shreya; Rankin, Helen; Ratliff, Camille D; Scala, Victoria; Schwartz, Nicholas U; Shuen, Jessica A; Xu, Amy; Xu, Thomas Q; Zhang, Yi; Rosenwald, Anne G; Burg, Martin G; Adams, Stephanie J; Baker, Morgan; Botsford, Bobbi; Brinkley, Briana; Brown, Carter; Emiah, Shadie; Enoch, Erica; Gier, Chad; Greenwell, Alyson; Hoogenboom, Lindsay; Matthews, Jordan E; McDonald, Mitchell; Mercer, Amanda; Monsma, Nicholaus; Ostby, Kristine; Ramic, Alen; Shallman, Devon; Simon, Matthew; Spencer, Eric; Tomkins, Trisha; Wendland, Pete; Wylie, Anna; Wolyniak, Michael J; Robertson, Gregory M; Smith, Samuel I; DiAngelo, Justin R; Sassu, Eric D; Bhalla, Satish C; Sharif, Karim A; Choeying, Tenzin; Macias, Jason S; Sanusi, Fareed; Torchon, Karvyn; Bednarski, April E; Alvarez, Consuelo J; Davis, Kristen C; Dunham, Carrie A; Grantham, Alaina J; Hare, Amber N; Schottler, Jennifer; Scott, Zackary W; Kuleck, Gary A; Yu, Nicole S; Kaehler, Marian M; Jipp, Jacob; Overvoorde, Paul J; Shoop, Elizabeth; Cyrankowski, Olivia; Hoover, Betsy; Kusner, Matt; Lin, Devry; Martinov, Tijana; Misch, Jonathan; Salzman, Garrett; Schiedermayer, Holly; Snavely, Michael; Zarrasola, Stephanie; Parrish, Susan; Baker, Atlee; Beckett, Alissa; Belella, Carissa; Bryant, Julie; Conrad, Turner; Fearnow, Adam; Gomez, Carolina; Herbstsomer, Robert A; Hirsch, Sarah; Johnson, Christen; Jones, Melissa; Kabaso, Rita; Lemmon, Eric; Vieira, Carolina Marques Dos Santos; McFarland, Darryl; McLaughlin, Christopher; Morgan, Abbie; Musokotwane, Sepo; Neutzling, William; Nietmann, Jana; Paluskievicz, Christina; Penn, Jessica; Peoples, Emily; Pozmanter, Caitlin; Reed, Emily; Rigby, Nichole; Schmidt, Lasse; Shelton, Micah; Shuford, Rebecca; Tirasawasdichai, Tiara; Undem, Blair; Urick, Damian; Vondy, Kayla; Yarrington, Bryan; Eckdahl, Todd T; Poet, Jeffrey L; Allen, Alica B; Anderson, John E; Barnett, Jason M; Baumgardner, Jordan S; Brown, Adam D; Carney, Jordan E; Chavez, Ramiro A; Christgen, Shelbi L; Christie, Jordan S; Clary, Andrea N; Conn, Michel A; Cooper, Kristen M; Crowley, Matt J; Crowley, Samuel T; Doty, Jennifer S; Dow, Brian A; Edwards, Curtis R; Elder, Darcie D; Fanning, John P; Janssen, Bridget M; Lambright, Anthony K; Lane, Curtiss E; Limle, Austin B; Mazur, Tammy; McCracken, Marly R; McDonough, Alexa M; Melton, Amy D; Minnick, Phillip J; Musick, Adam E; Newhart, William H; Noynaert, Joseph W; Ogden, Bradley J; Sandusky, Michael W; Schmuecker, Samantha M; Shipman, Anna L; Smith, Anna L; Thomsen, Kristen M; Unzicker, Matthew R; Vernon, William B; Winn, Wesley W; Woyski, Dustin S; Zhu, Xiao; Du, Chunguang; Ament, Caitlin; Aso, Soham; Bisogno, Laura Simone; Caronna, Jason; Fefelova, Nadezhda; Lopez, Lenin; Malkowitz, Lorraine; Marra, Jonathan; Menillo, Daniella; Obiorah, Ifeanyi; Onsarigo, Eric Nyabeta; Primus, Shekerah; Soos, Mahdi; Tare, Archana; Zidan, Ameer; Jones, Christopher J; Aronhalt, Todd; Bellush, James M; Burke, Christa; DeFazio, Steve; Does, Benjamin R; Johnson, Todd D; Keysock, Nicholas; Knudsen, Nelson H; Messler, James; Myirski, Kevin; Rekai, Jade Lea; Rempe, Ryan Michael; Salgado, Michael S; Stagaard, Erica; Starcher, Justin R; Waggoner, Andrew W; Yemelyanova, Anastasia K; Hark, Amy T; Bertolet, Anne; Kuschner, Cyrus E; Parry, Kesley; Quach, Michael; Shantzer, Lindsey; Shaw, Mary E; Smith, Mary A; Glenn, Omolara; Mason, Portia; Williams, Charlotte; Key, S Catherine Silver; Henry, Tyneshia C P; Johnson, Ashlee G; White, Jackie X; Haberman, Adam; Asinof, Sam; Drumm, Kelly; Freeburg, Trip; Safa, Nadia; Schultz, Darrin; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Wellinghoff, Jules; Hoopes, Laura L M; Chau, Kim M; Ward, Alyssa; Regisford, E Gloria C; Augustine, LaJerald; Davis-Reyes, Brionna; Echendu, Vivienne; Hales, Jasmine; Ibarra, Sharon; Johnson, Lauriaun; Ovu, Steven; Braverman, John M; Bahr, Thomas J; Caesar, Nicole M; Campana, Christopher; Cassidy, Daniel W; Cognetti, Peter A; English, Johnathan D; Fadus, Matthew C; Fick, Cameron N; Freda, Philip J; Hennessy, Bryan M; Hockenberger, Kelsey; Jones, Jennifer K; King, Jessica E; Knob, Christopher R; Kraftmann, Karen J; Li, Linghui; Lupey, Lena N; Minniti, Carl J; Minton, Thomas F; Moran, Joseph V; Mudumbi, Krishna; Nordman, Elizabeth C; Puetz, William J; Robinson, Lauren M; Rose, Thomas J; Sweeney, Edward P; Timko, Ashley S; Paetkau, Don W; Eisler, Heather L; Aldrup, Megan E; Bodenberg, Jessica M; Cole, Mara G; Deranek, Kelly M; DeShetler, Megan; Dowd, Rose M; Eckardt, Alexandra K; Ehret, Sharon C; Fese, Jessica; Garrett, Amanda D; Kammrath, Anna; Kappes, Michelle L; Light, Morgan R; Meier, Anne C; O'Rouke, Allison; Perella, Mallory; Ramsey, Kimberley; Ramthun, Jennifer R; Reilly, Mary T; Robinett, Deirdre; Rossi, Nadine L; Schueler, Mary Grace; Shoemaker, Emma; Starkey, Kristin M; Vetor, Ashley; Vrable, Abby; Chandrasekaran, Vidya; Beck, Christopher; Hatfield, Kristen R; Herrick, Douglas A; Khoury, Christopher B; Lea, Charlotte; Louie, Christopher A; Lowell, Shannon M; Reynolds, Thomas J; Schibler, Jeanine; Scoma, Alexandra H; Smith-Gee, Maxwell T; Tuberty, Sarah; Smith, Christopher D; Lopilato, Jane E; Hauke, Jeanette; Roecklein-Canfield, Jennifer A; Corrielus, Maureen; Gilman, Hannah; Intriago, Stephanie; Maffa, Amanda; Rauf, Sabya A; Thistle, Katrina; Trieu, Melissa; Winters, Jenifer; Yang, Bib; Hauser, Charles R; Abusheikh, Tariq; Ashrawi, Yara; Benitez, Pedro; Boudreaux, Lauren R; Bourland, Megan; Chavez, Miranda; Cruz, Samantha; Elliott, GiNell; Farek, Jesse R; Flohr, Sarah; Flores, Amanda H; Friedrichs, Chelsey; Fusco, Zach; Goodwin, Zane; Helmreich, Eric; Kiley, John; Knepper, John Mark; Langner, Christine; Martinez, Megan; Mendoza, Carlos; Naik, Monal; Ochoa, Andrea; Ragland, Nicolas; Raimey, England; Rathore, Sunil; Reza, Evangelina; Sadovsky, Griffin; Seydoux, Marie-Isabelle B; Smith, Jonathan E; 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Sunjed, Ray; Stamm, Joyce; Anderson, Morgan C; Bonifield, Bethany Grace; Coomes, Daniel; Dillman, Adam; Durchholz, Elaine J; Fafara-Thompson, Antoinette E; Gross, Meleah J; Gygi, Amber M; Jackson, Lesley E; Johnson, Amy; Kocsisova, Zuzana; Manghelli, Joshua L; McNeil, Kylie; Murillo, Michael; Naylor, Kierstin L; Neely, Jessica; Ogawa, Emmy E; Rich, Ashley; Rogers, Anna; Spencer, J Devin; Stemler, Kristina M; Throm, Allison A; Van Camp, Matt; Weihbrecht, Katie; Wiles, T Aaron; Williams, Mallory A; Williams, Matthew; Zoll, Kyle; Bailey, Cheryl; Zhou, Leming; Balthaser, Darla M; Bashiri, Azita; Bower, Mindy E; Florian, Kayla A; Ghavam, Nazanin; Greiner-Sosanko, Elizabeth S; Karim, Helmet; Mullen, Victor W; Pelchen, Carly E; Yenerall, Paul M; Zhang, Jiayu; Rubin, Michael R; Arias-Mejias, Suzette M; Bermudez-Capo, Armando G; Bernal-Vega, Gabriela V; Colon-Vazquez, Mariela; Flores-Vazquez, Arelys; Gines-Rosario, Mariela; Llavona-Cartagena, Ivan G; Martinez-Rodriguez, Javier O; Ortiz-Fuentes, Lionel; Perez-Colomba, Eliezer O; Perez-Otero, Joseph; Rivera, Elisandra; Rodriguez-Giron, Luke J; Santiago-Sanabria, Arnaldo J; Senquiz-Gonzalez, Andrea M; delValle, Frank R Soto; Vargas-Franco, Dorianmarie; Velázquez-Soto, Karla I; Zambrana-Burgos, Joan D; Martinez-Cruzado, Juan Carlos; Asencio-Zayas, Lillyann; Babilonia-Figueroa, Kevin; Beauchamp-Pérez, Francis D; Belén-Rodríguez, Juliana; Bracero-Quiñones, Luciann; Burgos-Bula, Andrea P; Collado-Méndez, Xavier A; Colón-Cruz, Luis R; Correa-Muller, Ana I; Crooke-Rosado, Jonathan L; Cruz-García, José M; Defendini-Ávila, Marianna; Delgado-Peraza, Francheska M; Feliciano-Cancela, Alex J; Gónzalez-Pérez, Valerie M; Guiblet, Wilfried; Heredia-Negrón, Aldo; Hernández-Muñiz, Jennifer; Irizarry-González, Lourdes N; Laboy-Corales, Ángel L; Llaurador-Caraballo, Gabriela A; Marín-Maldonado, Frances; Marrero-Llerena, Ulises; Martell-Martínez, Héctor A; Martínez-Traverso, Idaliz M; Medina-Ortega, Kiara N; Méndez-Castellanos, Sonya G; Menéndez-Serrano, Krizia C; Morales-Caraballo, Carol I; Ortiz-DeChoudens, Saryleine; Ortiz-Ortiz, Patricia; Pagán-Torres, Hendrick; Pérez-Afanador, Diana; Quintana-Torres, Enid M; Ramírez-Aponte, Edwin G; Riascos-Cuero, Carolina; Rivera-Llovet, Michelle S; Rivera-Pagán, Ingrid T; Rivera-Vicéns, Ramón E; Robles-Juarbe, Fabiola; Rodríguez-Bonilla, Lorraine; Rodríguez-Echevarría, Brian O; Rodríguez-García, Priscila M; Rodríguez-Laboy, Abneris E; Rodríguez-Santiago, Susana; Rojas-Vargas, Michael L; Rubio-Marrero, Eva N; Santiago-Colón, Albeliz; Santiago-Ortiz, Jorge L; Santos-Ramos, Carlos E; Serrano-González, Joseline; Tamayo-Figueroa, Alina M; Tascón-Peñaranda, Edna P; Torres-Castillo, José L; Valentín-Feliciano, Nelson A; Valentín-Feliciano, Yashira M; Vargas-Barreto, Nadyan M; Vélez-Vázquez, Miguel; Vilanova-Vélez, Luis R; Zambrana-Echevarría, Cristina; MacKinnon, Christy; Chung, Hui-Min; Kay, Chris; Pinto, Anthony; Kopp, Olga R; Burkhardt, Joshua; Harward, Chris; Allen, Robert; Bhat, Pavan; Chang, Jimmy Hsiang-Chun; Chen, York; Chesley, Christopher; Cohn, Dara; DuPuis, David; Fasano, Michael; Fazzio, Nicholas; Gavinski, Katherine; Gebreyesus, Heran; Giarla, Thomas; Gostelow, Marcus; Greenstein, Rachel; Gunasinghe, Hashini; Hanson, Casey; Hay, Amanda; He, Tao Jian; Homa, Katie; Howe, Ruth; Howenstein, Jeff; Huang, Henry; Khatri, Aaditya; Kim, Young Lu; Knowles, Olivia; Kong, Sarah; Krock, Rebecca; Kroll, Matt; Kuhn, Julia; Kwong, Matthew; Lee, Brandon; Lee, Ryan; Levine, Kevin; Li, Yedda; Liu, Bo; Liu, Lucy; Liu, Max; Lousararian, Adam; Ma, Jimmy; Mallya, Allyson; Manchee, Charlie; Marcus, Joseph; McDaniel, Stephen; Miller, Michelle L; Molleston, Jerome M; Diez, Cristina Montero; Ng, Patrick; Ngai, Natalie; Nguyen, Hien; Nylander, Andrew; Pollack, Jason; Rastogi, Suchita; Reddy, Himabindu; Regenold, Nathaniel; Sarezky, Jon; Schultz, Michael; Shim, Jien; Skorupa, Tara; Smith, Kenneth; Spencer, Sarah J; Srikanth, Priya; Stancu, Gabriel; Stein, Andrew P; Strother, Marshall; Sudmeier, Lisa; Sun, Mengyang; Sundaram, Varun; Tazudeen, Noor; Tseng, Alan; Tzeng, Albert; Venkat, Rohit; Venkataram, Sandeep; Waldman, Leah; Wang, Tracy; Yang, Hao; Yu, Jack Y; Zheng, Yin; Preuss, Mary L; Garcia, Angelica; Juergens, Matt; Morris, Robert W; Nagengast, Alexis A; Azarewicz, Julie; Carr, Thomas J; Chichearo, Nicole; Colgan, Mike; Donegan, Megan; Gardner, Bob; Kolba, Nik; Krumm, Janice L; Lytle, Stacey; MacMillian, Laurell; Miller, Mary; Montgomery, Andrew; Moretti, Alysha; Offenbacker, Brittney; Polen, Mike; Toth, John; Woytanowski, John; Kadlec, Lisa; Crawford, Justin; Spratt, Mary L; Adams, Ashley L; Barnard, Brianna K; Cheramie, Martin N; Eime, Anne M; Golden, Kathryn L; Hawkins, Allyson P; Hill, Jessica E; Kampmeier, Jessica A; Kern, Cody D; Magnuson, Emily E; Miller, Ashley R; Morrow, Cody M; Peairs, Julia C; Pickett, Gentry L; Popelka, Sarah A; Scott, Alexis J; Teepe, Emily J; TerMeer, Katie A; Watchinski, Carmen A; Watson, Lucas A; Weber, Rachel E; Woodard, Kate A; Barnard, Daron C; Appiah, Isaac; Giddens, Michelle M; McNeil, Gerard P; Adebayo, Adeola; Bagaeva, Kate; Chinwong, Justina; Dol, Chrystel; George, Eunice; Haltaufderhyde, Kirk; Haye, Joanna; Kaur, Manpreet; Semon, Max; Serjanov, Dmitri; Toorie, Anika; Wilson, Christopher; Riddle, Nicole C; Buhler, Jeremy; Mardis, Elaine R; Elgin, Sarah C R

    2015-03-04

    The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25-50%) than euchromatic reference regions (3-11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11-27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4-3.6 vs. 8.4-8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu. Copyright © 2015 Leung et al.

  12. Chemical compounds related to the predation risk posed by malacophagous ground beetles alter self-maintenance behavior of naive slugs (Deroceras reticulatum.

    Directory of Open Access Journals (Sweden)

    Piotr Bursztyka

    Full Text Available Evidence that terrestrial gastropods are able to detect chemical cues from their predators is obvious yet scarce, despite the scientific relevance of the topic to enhancing our knowledge in this area. This study examines the influence of cuticular extracts from predacious ground beetles (Carabus auratus, Carabus hispanus, Carabus nemoralis and Carabus coriaceus, and a neutral insect species (Musca domestica on the shelter-seeking behavior of naive slugs (Deroceras reticulatum. Slugs, known to have a negative phototactic response, were exposed to light, prompting them to make a choice between either a shelter treated with a cuticular extract or a control shelter treated with pure ethyl alcohol. Their behavioral responses were recorded for one hour in order to determine their first shelter choice, their final position, and to compare the percentage of time spent in the control shelters with the time spent in the treated shelters.The test proved to be very effective: slugs spent most of the experiment in a shelter. They spent significantly more time in the control shelter than in the shelter treated with either C. nemoralis (Z = 2.43; p = 0.0151; Wilcoxon matched-pairs signed-ranks test or C. coriaceus cuticular extracts (Z = 3.31; p<0.01; Wilcoxon matched-pairs signed-ranks test, with a seemingly stronger avoidance effect when presented with C. coriaceus extracts. The other cuticular extracts had no significant effect on any of the behavioral items measured. Although it cannot be entirely excluded that the differences observed, are partly due to the intrinsic properties of the vehicle employed to build the cuticular extracts, the results suggest that slugs can innately discriminate amongst different potential predators and adjust their behavioral response according to the relevance of the threat conveyed by their predator's chemical cues.

  13. Chemical compounds related to the predation risk posed by malacophagous ground beetles alter self-maintenance behavior of naive slugs (Deroceras reticulatum).

    Science.gov (United States)

    Bursztyka, Piotr; Saffray, Dominique; Lafont-Lecuelle, Céline; Brin, Antoine; Pageat, Patrick

    2013-01-01

    Evidence that terrestrial gastropods are able to detect chemical cues from their predators is obvious yet scarce, despite the scientific relevance of the topic to enhancing our knowledge in this area. This study examines the influence of cuticular extracts from predacious ground beetles (Carabus auratus, Carabus hispanus, Carabus nemoralis and Carabus coriaceus), and a neutral insect species (Musca domestica) on the shelter-seeking behavior of naive slugs (Deroceras reticulatum). Slugs, known to have a negative phototactic response, were exposed to light, prompting them to make a choice between either a shelter treated with a cuticular extract or a control shelter treated with pure ethyl alcohol. Their behavioral responses were recorded for one hour in order to determine their first shelter choice, their final position, and to compare the percentage of time spent in the control shelters with the time spent in the treated shelters.The test proved to be very effective: slugs spent most of the experiment in a shelter. They spent significantly more time in the control shelter than in the shelter treated with either C. nemoralis (Z = 2.43; p = 0.0151; Wilcoxon matched-pairs signed-ranks test) or C. coriaceus cuticular extracts (Z = 3.31; p<0.01; Wilcoxon matched-pairs signed-ranks test), with a seemingly stronger avoidance effect when presented with C. coriaceus extracts. The other cuticular extracts had no significant effect on any of the behavioral items measured. Although it cannot be entirely excluded that the differences observed, are partly due to the intrinsic properties of the vehicle employed to build the cuticular extracts, the results suggest that slugs can innately discriminate amongst different potential predators and adjust their behavioral response according to the relevance of the threat conveyed by their predator's chemical cues.

  14. An antioxidant extract of tropical lichen, Parmotrema reticulatum, induces cell cycle arrest and apoptosis in breast carcinoma cell line MCF-7.

    Directory of Open Access Journals (Sweden)

    Nikhil Baban Ghate

    Full Text Available This report highlights the phytochemical analysis, antioxidant potential and anticancer activity against breast carcinoma of 70% methanolic extract of lichen, Parmotrema reticulatum (PRME. Phytochemical analysis of PRME confirms the presence of various phytoconstituents like alkaloids, carbohydrates, flavonoids, glycosides, phenols, saponins, tannins, anthraquinones, and ascorbic acid; among which alkaloids, phenols and flavonoids are found in abundant amount. High performance liquid chromatography (HPLC analysis of PRME revealed the presence of catechin, purpurin, tannic acid and reserpine. Antioxidant activity was evaluated by nine separate methods. PRME showed excellent hydroxyl and hypochlorous radical scavenging as well as moderate DPPH, superoxide, singlet oxygen, nitric oxide and peroxynitrite scavenging activity. Cytotoxicity of PRME was tested against breast carcinoma (MCF-7, lung carcinoma (A549 and normal lung fibroblast (WI-38 using WST-1 method. PRME was found cytotoxic against MCF-7 cells with an IC50 value 130.03 ± 3.11 µg/ml while negligible cytotoxicity was observed on A549 and WI-38 cells. Further flow cytometric study showed that PRME halted the MCF-7 cells in S and G2/M phases and induces apoptosis in dose as well as time dependent manner. Cell cycle arrest was associated with downregulation of cyclin B1, Cdk-2 and Cdc25C as well as slight decrease in the expression of Cdk-1 and cyclin A1 with subsequent upregulation of p53 and p21. Moreover PRME induced Bax and inhibited Bcl-2 expression, which results in increasing Bax/Bcl-2 ratio and activation of caspase cascade. This ultimately leads to PARP degradation and induces apoptosis in MCF-7 cells. It can be hypothesised from the current study that the antioxidant and anticancer potential of the PRME may reside in the phytoconstitutents present in it and therefore, PRME may be used as a possible source of natural antioxidant that may be developed to an anticancer agent.

  15. Statistical analysis of natural radiation levels inside the UNICAMP campus through the use of Geiger-Muller counter; Analise estatistica dos niveis de radiacao natural dentro da UNICAMP atraves do uso de contador Geiger-Muller

    Energy Technology Data Exchange (ETDEWEB)

    Fontolan, Juliana A.; Biral, Antonio Renato P., E-mail: fontolanjuliana@gmail.com.br, E-mail: biral@ceb.unicamp.br [Hospital das Clinicas (CEB/UNICAMP), Campinas, SP (Brazil). Centro de Engenharia Biomedica

    2013-07-01

    It is known that the distribution at time intervals of random and unrelated events leads to the Poisson distribution . This work aims to study the distribution in time intervals of events resulting from radioactive decay of atoms present in the UNICAMP where activities involving the use of ionizing radiation are performed environments . The proposal is that the distribution surveys at intervals of these events in different locations of the university are carried out through the use of a Geiger-Mueller tube . In a next step , the evaluation of distributions obtained by using non- parametric statistics (Chi- square and Kolmogorov Smirnoff) will be taken . For analyzes involving correlations we intend to use the ANOVA (Analysis of Variance) statistical tool . Measured in six different places within the Campinas , with the use of Geiger- Muller its count mode and a time window of 20 seconds was performed . Through statistical tools chi- square and Kolmogorov Smirnoff tests, using the EXCEL program , it was observed that the distributions actually refer to a Poisson distribution. Finally, the next step is to perform analyzes involving correlations using the statistical tool ANOVA.

  16. Opposing Actions of Fgf8a on Notch Signaling Distinguish Two Muller Glial Cell Populations that Contribute to Retina Growth and Regeneration

    Directory of Open Access Journals (Sweden)

    Jin Wan

    2017-04-01

    Full Text Available The teleost retina grows throughout life and exhibits a robust regenerative response following injury. Critical to both these events are Muller glia (or, Muller glial cells; MGs, which produce progenitors for retinal growth and repair. We report that Fgf8a may be an MG niche factor that acts through Notch signaling to regulate spontaneous and injury-dependent MG proliferation. Remarkably, forced Fgf8a expression inhibits Notch signaling and stimulates MG proliferation in young tissue but increases Notch signaling and suppresses MG proliferation in older tissue. Furthermore, cessation of Fgf8a signaling enhances MG proliferation in both young and old retinal tissue. Our study suggests that multiple MG populations contribute to retinal growth and regeneration, and it reveals a previously unappreciated role for Fgf8a and Notch signaling in regulating MG quiescence, activation, and proliferation.

  17. Magnetic Random Access Memory based non-volatile asynchronous Muller cell for ultra-low power autonomous applications

    Science.gov (United States)

    Di Pendina, G.; Zianbetov, E.; Beigne, E.

    2015-05-01

    Micro and nano electronic integrated circuit domain is today mainly driven by the advent of the Internet of Things for which the constraints are strong, especially in terms of power consumption and autonomy, not only during the computing phases but also during the standby or idle phases. In such ultra-low power applications, the circuit has to meet new constraints mainly linked to its changing energetic environment: long idle phases, automatic wake up, data back-up when the circuit is sporadically turned off, and ultra-low voltage power supply operation. Such circuits have to be completely autonomous regarding their unstable environment, while remaining in an optimum energetic configuration. Therefore, we propose in this paper the first MRAM-based non-volatile asynchronous Muller cell. This cell has been simulated and characterized in a very advanced 28 nm CMOS fully depleted silicon-on-insulator technology, presenting good power performance results due to an extremely efficient body biasing control together with ultra-wide supply voltage range from 160 mV up to 920 mV. The leakage current can be reduced to 154 pA thanks to reverse body biasing. We also propose an efficient standard CMOS bulk version of this cell in order to be compatible with different fabrication processes.

  18. Magnetic Random Access Memory based non-volatile asynchronous Muller cell for ultra-low power autonomous applications

    Energy Technology Data Exchange (ETDEWEB)

    Di Pendina, G., E-mail: gregory.dipendina@cea.fr, E-mail: eldar.zianbetov@cea.fr, E-mail: edith.beigne@cea.fr; Zianbetov, E., E-mail: gregory.dipendina@cea.fr, E-mail: eldar.zianbetov@cea.fr, E-mail: edith.beigne@cea.fr [Univ. Grenoble Alpes, INAC-SPINTEC, F-38000 Grenoble (France); CNRS, SPINTEC, F-38000 Grenoble (France); CEA, INAC-SPINTEC, F-38000 Grenoble (France); Beigne, E., E-mail: gregory.dipendina@cea.fr, E-mail: eldar.zianbetov@cea.fr, E-mail: edith.beigne@cea.fr [Univ. Grenoble Alpes, CEA, LETI, F-38000 Grenoble (France)

    2015-05-07

    Micro and nano electronic integrated circuit domain is today mainly driven by the advent of the Internet of Things for which the constraints are strong, especially in terms of power consumption and autonomy, not only during the computing phases but also during the standby or idle phases. In such ultra-low power applications, the circuit has to meet new constraints mainly linked to its changing energetic environment: long idle phases, automatic wake up, data back-up when the circuit is sporadically turned off, and ultra-low voltage power supply operation. Such circuits have to be completely autonomous regarding their unstable environment, while remaining in an optimum energetic configuration. Therefore, we propose in this paper the first MRAM-based non-volatile asynchronous Muller cell. This cell has been simulated and characterized in a very advanced 28 nm CMOS fully depleted silicon-on-insulator technology, presenting good power performance results due to an extremely efficient body biasing control together with ultra-wide supply voltage range from 160 mV up to 920 mV. The leakage current can be reduced to 154 pA thanks to reverse body biasing. We also propose an efficient standard CMOS bulk version of this cell in order to be compatible with different fabrication processes.

  19. Statistical analysis of natural radiation levels inside the UNICAMP campus through the use of Geiger-Muller counter

    International Nuclear Information System (INIS)

    Fontolan, Juliana A.; Biral, Antonio Renato P.

    2013-01-01

    It is known that the distribution at time intervals of random and unrelated events leads to the Poisson distribution . This work aims to study the distribution in time intervals of events resulting from radioactive decay of atoms present in the UNICAMP where activities involving the use of ionizing radiation are performed environments . The proposal is that the distribution surveys at intervals of these events in different locations of the university are carried out through the use of a Geiger-Mueller tube . In a next step , the evaluation of distributions obtained by using non- parametric statistics (Chi- square and Kolmogorov Smirnoff) will be taken . For analyzes involving correlations we intend to use the ANOVA (Analysis of Variance) statistical tool . Measured in six different places within the Campinas , with the use of Geiger- Muller its count mode and a time window of 20 seconds was performed . Through statistical tools chi- square and Kolmogorov Smirnoff tests, using the EXCEL program , it was observed that the distributions actually refer to a Poisson distribution. Finally, the next step is to perform analyzes involving correlations using the statistical tool ANOVA

  20. Magnetic Random Access Memory based non-volatile asynchronous Muller cell for ultra-low power autonomous applications

    International Nuclear Information System (INIS)

    Di Pendina, G.; Zianbetov, E.; Beigne, E.

    2015-01-01

    Micro and nano electronic integrated circuit domain is today mainly driven by the advent of the Internet of Things for which the constraints are strong, especially in terms of power consumption and autonomy, not only during the computing phases but also during the standby or idle phases. In such ultra-low power applications, the circuit has to meet new constraints mainly linked to its changing energetic environment: long idle phases, automatic wake up, data back-up when the circuit is sporadically turned off, and ultra-low voltage power supply operation. Such circuits have to be completely autonomous regarding their unstable environment, while remaining in an optimum energetic configuration. Therefore, we propose in this paper the first MRAM-based non-volatile asynchronous Muller cell. This cell has been simulated and characterized in a very advanced 28 nm CMOS fully depleted silicon-on-insulator technology, presenting good power performance results due to an extremely efficient body biasing control together with ultra-wide supply voltage range from 160 mV up to 920 mV. The leakage current can be reduced to 154 pA thanks to reverse body biasing. We also propose an efficient standard CMOS bulk version of this cell in order to be compatible with different fabrication processes

  1. Shared Reed-Muller Decision Diagram Based Thermal-Aware AND-XOR Decomposition of Logic Circuits

    Directory of Open Access Journals (Sweden)

    Apangshu Das

    2016-01-01

    Full Text Available The increased number of complex functional units exerts high power-density within a very-large-scale integration (VLSI chip which results in overheating. Power-densities directly converge into temperature which reduces the yield of the circuit. An adverse effect of power-density reduction is the increase in area. So, there is a trade-off between area and power-density. In this paper, we introduce a Shared Reed-Muller Decision Diagram (SRMDD based on fixed polarity AND-XOR decomposition to represent multioutput Boolean functions. By recursively applying transformations and reductions, we obtained a compact SRMDD. A heuristic based on Genetic Algorithm (GA increases the sharing of product terms by judicious choice of polarity of input variables in SRMDD expansion and a suitable area and power-density trade-off has been enumerated. This is the first effort ever to incorporate the power-density as a measure of temperature estimation in AND-XOR expansion process. The results of logic synthesis are incorporated with physical design in CADENCE digital synthesis tool to obtain the floor-plan silicon area and power profile. The proposed thermal-aware synthesis has been validated by obtaining absolute temperature of the synthesized circuits using HotSpot tool. We have experimented with 29 benchmark circuits. The minimized AND-XOR circuit realization shows average savings up to 15.23% improvement in silicon area and up to 17.02% improvement in temperature over the sum-of-product (SOP based logic minimization.

  2. MOLLUSCA' BIODIVERSITY (GASTROPODA AND BIVALVIA AS A BIO INDICATOR OF QUALITY OF WATER IN THE COASTAL ISLAND OF TUNDA ISLAND, BANTEN

    Directory of Open Access Journals (Sweden)

    Indria Wahyuni

    2017-07-01

    Full Text Available The research has been done on Juli 2017 in the coastal region of Tunda Island. This study aims to determine the Biodiversity of Mollusca (Gastropoda and Bivalvia As Bioindicator of Water Quality In Coastal Area of Tunda Island, Banten. Sampling consists of 2 observation stations, namely the mangrove coastal area (3 transects and the seagrass coastal area (2 transects determined by purposive sampling. The observation of each station is done by using the quadratic transect method with 100 m transect line distance, and in each transect line there are 5 observation plots measuring 1m2 x 1m2. The data analysis includes density, biodiversity, bio-indicators of water quality based on diversity index. Result of research on 5 transect found 45 type Mollusca which represent 2 class, that is Gastropoda class of 29 species Gastropoda joined in 14 Family. As for Bivalvia class found 16 species incorporated in 9 families. The total density of Mollusca is 541.2 ind / m2 which consists of 392.4 ind / m2 for Gastropoda class and 148.8 ind / m2 for Bivalvia class. Mollusca diversity was calculated using the diversity index of Shannon-Wienner (H '. The results of diversity index ranged from 3.1356 - 3.3314 with high category. Bioindicator of aquatic quality using diversity index indicates that the coastal area of Tunda Island belongs to a very mildly polluted category.

  3. The Histopathology of the Infection of Tilapia rendalli and Hypostomus regani (Osteichthyes by Lasidium Larvae of Anodontites trapesialis (Mollusca, Bivalvia

    Directory of Open Access Journals (Sweden)

    Ângela Teresa Silva-Souza

    2002-04-01

    Full Text Available It is described the histopathology of the infection of Tilapia rendalli (Osteichthyes, Perciformes, Cichlidae and Hypostomus regani (Osteichthyes, Siluriformes, Loricariidae by lasidium larvae of Anodontites trapesialis (Mollusca, Bivalvia, Mycetopodidae. The larvae were encysted within the epidermis of the host, being surrounded by a thin hyaline membrane, 3-6 µm thick, of parasite origin. A proliferative host cell reaction did not occur. The histopathology of the infection shows that the lesions induced by the parasites are minimal. However, the numerous small lesions produced by the release of the larvae may provide optimal conditions for the infection by opportunistic pathogens, namely fungus, which may eventually cause the death of the host.

  4. Quitones (Mollusca: Polyplacophora de El Salvador, América Central

    Directory of Open Access Journals (Sweden)

    Cedar I García-Ríos

    2007-03-01

    Full Text Available En El Salvador se habían registrado los poliplacóforos Chaetopleura lurida (Sowerby, 1832; Ischnochiton guatemalensis (Thiele, 1910; Ceratozona angusta (Thiele, 1909; Chiton stokesii (Broderip, 1832 y Acantochitona exquisita (Pilsbry, 1893. Recolectamos quitones en aguas someras de El Salvador en julio del 2002, agragando a la lista a Lepidochitona beanii (Carpenter, 1857; Ischnochiton dispar (Sowerby, 1832; Stenoplax limaciformis (Sowerby, 1832; Callistochiton expressus (Carpenter, 1865; Acanthochitona arragonites (Carpenter, 1867; Acanthochitona ferreirai (Lyons, 1988 y Acanthochitona hirudiniformis (Sowerby, 1832. Ampliamos la distribución documentada de I. dispar hacia el norte y describimos brevemente una especie innominada de Lepidochitona.Chitons (Mollusca: Polyplacophora from El Salvador, Central America. Collections of 11 species of shallow water Polyplacophora from El Salvador were made in July 2002. Previously only five species had been documented in El Salvador: Chaetopleura lurida (Sowerby, 1832; Ischnochiton guatemalensis (Thiele, 1910; Ceratozona angusta (Thiele, 1909; Chiton stokesii (Broderip, 1832 and Acantochitona exquisita (Pilsbry, 1893. Of these, I. guatemalensis and A. exquisita were not collected in this census. Seven other species are reported here for El Salvador for the first time: Lepidochitona beanii (Carpenter, 1857; Ischnochiton dispar (Sowerby, 1832; Stenoplax limaciformis (Sowerby, 1832; Callistochiton expressus (Carpenter, 1865; Acanthochitona arragonites (Carpenter, 1867; A. ferreirai (Lyons, 1988 and A. hirudiniformis (Sowerby, 1832. The known geographic distribution of I. dispar is extended to the north. An un-named species of Lepidochitona is briefly described. Rev. Biol. Trop. 55 (1: 171-176. Epub 2007 March. 31.

  5. Mollusca from a species-rich deep-water Leptometra community in the Alboran Sea

    Directory of Open Access Journals (Sweden)

    Serge Gofas

    2014-12-01

    Full Text Available An exceptional species richness for Mollusca was found on Avempace bank (349-365 m, Djibouti group, Alboran Sea, where the most abundant species was the crinoid Leptometra phalangium. A sample of sediment sieved on a 0.5-mm mesh yielded 156 species of molluscs (83 live-taken, 1772 specimens with a high Shannon-Wiener diversity index (H’(log2=3.60. The dominant mollusc was Limopsis aurita and the six most common species accounted for 77% of the specimens. On the other hand, 42 species were represented by only one or two specimens. Two species are described as new, three more are first findings in the Mediterranean and two are first findings in Iberian waters. One-third of the species have not been reported from the neighbouring, well-explored Alboran Island platform. There is a considerable balance between the trophic groups, denoting a stable and structured community. Most of the species have an extensive Atlantic range, and most have a planktonic larval stage. Therefore, it can be hypothesized that the fauna benefits from a diverse influx of larvae carried in by the more superficial incoming Atlantic current. Because of its exceptional richness, this type of bathyal community with Leptometra and Limopsis should be considered a high priority for habitat conservation in the Mediterranean deep sea.

  6. Effects of the nematode Phasmarhabditis hermaphrodita and of venom from the endoparasitic wasp Pimpla hypochondriaca on survival and food consumption of the pest slug Deroceras reticulatum; implications for novel biocontrol strategies.

    Science.gov (United States)

    Richards, Elaine H; DeMarzo, Damian; Port, Gordon R; Dani, M Paulina; Walters, Keith F A

    2008-07-01

    Controlling pests through disruption of biochemical pathways by physiologically active compounds/factors from animals and plants represents an expanding field of research. The authors investigated whether such factors in venom from the wasp Pimpla hypochondriaca (Retzius) can affect the viability and food consumption of the slug Deroceras reticulatum (Müller), and whether they can improve the efficacy of nematode-induced slug mortality. Exposure of slugs to 4 mL of water containing 500, 1000 and 5000 Phasmarhabditis hermaphrodita (Schneider) resulted in significant increases in mortality (with hazard ratios of 3.5, 3.9 and 5.8 respectively) and significant reductions in total food consumption and mean food consumption each day for 21 days. Injection of slugs with 4, 8 or 12 microL of P. hypochondriaca venom resulted in significant increases in mortality (with hazard ratios of 3.3, 4.5 and 9.0 respectively) and significant reductions in total food consumption compared with the controls. However, there was no significant effect of venom on the mean food consumption on individual days of the 21 day assay period, although significant reductions occurred for the 8 and 12 microL doses up to day 10. Injecting slugs with 4 microL of venom prior to exposure to 500 nematodes had no synergistic effect on either mortality or food consumption compared with either of the individual treatments. Pimpla hypochondriaca venom contains factors capable of killing and reducing food consumption by D. reticulatum. The utilization of these factors as components of integrated pest management strategies is discussed.

  7. Differential occurrence of chromosome inversion polymorphisms among Muller's elements in three species of the tripunctata group of Drosophila, including a species with fast chromosomal evolution.

    Science.gov (United States)

    Brianti, Mitsue T; Ananina, Galina; Klaczko, Louis B

    2013-01-01

    Detailed chromosome maps with reliable homologies among chromosomes of different species are the first step to study the evolution of the genetic architecture in any set of species. Here, we present detailed photo maps of the polytene chromosomes of three closely related species of the tripunctata group (subgenus Drosophila): Drosophila mediopunctata, D. roehrae, and D. unipunctata. We identified Muller's elements in each species, using FISH, establishing reliable chromosome homologies among species and D. melanogaster. The simultaneous analysis of chromosome inversions revealed a distribution pattern for the inversion polymorphisms among Muller's elements in the three species. Element E is the most polymorphic, with many inversions in each species. Element C follows; while the least polymorphic elements are B and D. While interesting, it remains to be determined how general this pattern is among species of the tripunctata group. Despite previous studies showing that D. mediopunctata and D. unipunctata are phylogenetically closer to each other than to D. roehrae, D. unipunctata shows rare karyotypic changes. It has two chromosome fusions: an additional heterochromatic chromosome pair and a pericentric inversion in the X chromosome. This especial conformation suggests a fast chromosomal evolution that deserves further study.

  8. The threshold vs LNT showdown: Dose rate findings exposed flaws in the LNT model part 1. The Russell-Muller debate

    Energy Technology Data Exchange (ETDEWEB)

    Calabrese, Edward J., E-mail: edwardc@schoolph.umass.edu

    2017-04-15

    This paper assesses the discovery of the dose-rate effect in radiation genetics and how it challenged fundamental tenets of the linear non-threshold (LNT) dose response model, including the assumptions that all mutational damage is cumulative and irreversible and that the dose-response is linear at low doses. Newly uncovered historical information also describes how a key 1964 report by the International Commission for Radiological Protection (ICRP) addressed the effects of dose rate in the assessment of genetic risk. This unique story involves assessments by two leading radiation geneticists, Hermann J. Muller and William L. Russell, who independently argued that the report's Genetic Summary Section on dose rate was incorrect while simultaneously offering vastly different views as to what the report's summary should have contained. This paper reveals occurrences of scientific disagreements, how conflicts were resolved, which view(s) prevailed and why. During this process the Nobel Laureate, Muller, provided incorrect information to the ICRP in what appears to have been an attempt to manipulate the decision-making process and to prevent the dose-rate concept from being adopted into risk assessment practices. - Highlights: • The discovery of radiation dose rate challenged the scientific basis of LNT. • Radiation dose rate occurred in males and females. • The dose rate concept supported a threshold dose-response for radiation.

  9. The threshold vs LNT showdown: Dose rate findings exposed flaws in the LNT model part 1. The Russell-Muller debate

    International Nuclear Information System (INIS)

    Calabrese, Edward J.

    2017-01-01

    This paper assesses the discovery of the dose-rate effect in radiation genetics and how it challenged fundamental tenets of the linear non-threshold (LNT) dose response model, including the assumptions that all mutational damage is cumulative and irreversible and that the dose-response is linear at low doses. Newly uncovered historical information also describes how a key 1964 report by the International Commission for Radiological Protection (ICRP) addressed the effects of dose rate in the assessment of genetic risk. This unique story involves assessments by two leading radiation geneticists, Hermann J. Muller and William L. Russell, who independently argued that the report's Genetic Summary Section on dose rate was incorrect while simultaneously offering vastly different views as to what the report's summary should have contained. This paper reveals occurrences of scientific disagreements, how conflicts were resolved, which view(s) prevailed and why. During this process the Nobel Laureate, Muller, provided incorrect information to the ICRP in what appears to have been an attempt to manipulate the decision-making process and to prevent the dose-rate concept from being adopted into risk assessment practices. - Highlights: • The discovery of radiation dose rate challenged the scientific basis of LNT. • Radiation dose rate occurred in males and females. • The dose rate concept supported a threshold dose-response for radiation.

  10. Homology and homoplasy of swimming behaviors and neural circuits in the Nudipleura (Mollusca, Gastropoda, Opisthobranchia)

    Science.gov (United States)

    Newcomb, James M.; Sakurai, Akira; Lillvis, Joshua L.; Gunaratne, Charuni A.; Katz, Paul S.

    2012-01-01

    How neural circuit evolution relates to behavioral evolution is not well understood. Here the relationship between neural circuits and behavior is explored with respect to the swimming behaviors of the Nudipleura (Mollusca, Gastropoda, Opithobranchia). Nudipleura is a diverse monophyletic clade of sea slugs among which only a small percentage of species can swim. Swimming falls into a limited number of categories, the most prevalent of which are rhythmic left–right body flexions (LR) and rhythmic dorsal–ventral body flexions (DV). The phylogenetic distribution of these behaviors suggests a high degree of homoplasy. The central pattern generator (CPG) underlying DV swimming has been well characterized in Tritonia diomedea and in Pleurobranchaea californica. The CPG for LR swimming has been elucidated in Melibe leonina and Dendronotus iris, which are more closely related. The CPGs for the categorically distinct DV and LR swimming behaviors consist of nonoverlapping sets of homologous identified neurons, whereas the categorically similar behaviors share some homologous identified neurons, although the exact composition of neurons and synapses in the neural circuits differ. The roles played by homologous identified neurons in categorically distinct behaviors differ. However, homologous identified neurons also play different roles even in the swim CPGs of the two LR swimming species. Individual neurons can be multifunctional within a species. Some of those functions are shared across species, whereas others are not. The pattern of use and reuse of homologous neurons in various forms of swimming and other behaviors further demonstrates that the composition of neural circuits influences the evolution of behaviors. PMID:22723353

  11. Diversidad y microestructura de quitones (Mollusca: Polyplacophora del Caribe de Costa Rica

    Directory of Open Access Journals (Sweden)

    Cedar I García-Ríos

    2011-03-01

    Full Text Available Los poliplacóforos asociados a los arrecifes de coral en la costa caribeña de Costa Rica han sido poco estudiados. El examen del cascajo de coral acumulado en el sublitoral somero, en cuatro estaciones de colección, localizadas en la Provincia de Limón reveló una diversidad de quitones mayor a la documentada. Anteriormente se habían registrado ocho especies para el Caribe costaricense: Ischnochiton erythronotus (C.B. Adams, 1845; Ischnoplax pectinata (Sowerby 1840; Stenoplax boogii (Haddon, 1886; S. purpurascens (C.B. Adams, 1845; Acanthopleura granulata (Gmelin, 1791; Chiton marmoratus Gmelin, 1791; C. tuberculatus Linnaeus, 1758; Acanthochitona rhodea (Pilsbry, 1893. Otras cinco se registran aquí por primera vez: Callistochiton portobelensis Ferreira 1976; Ischnochiton kaasi Ferreira 1987; I. pseudovirgatus Kaas 1972; Acanthochitona balesae Abbott 1954; Cryptoconchus floridanus (Dall 1889.Diversity and microstructure of quitons (Mollusca: Polyplacophora from the Caribbean of Costa Rica. The polyplacophorans of the coral reef on the Caribbean coast of Costa Rica have been insufficiently studied. The examination of coral rubble accumulated in the shallow sublitoral waters on four collection stations in Provincia Limón revealed a higher diversity of chitons than was documented. From the country eight species were previously known: Ischnochiton erythronotus (C.B. Adams 1845; Ischnoplax pectinata (Sowerby 1840; Stenoplax boogii (Haddon 1886; S. purpurascens (C.B. Adams 1845; Acanthopleura granulate (Gmelin 1791; Chiton marmoratus Gmelin 1791; C. tuberculatus Linnaeus 1758 and Acanthochitona rhodea (Pilsbry 1893. This study added five more species that are reported here for the first time: Callistochiton portobelensis Ferreira 1976; Ischnochiton kaasi Ferreira 1987; I. pseudovirgatus Kaas 1972; Acanthochitona balesae Abbott 1954 and Cryptoconchus floridanus (Dall 1889. Rev. Biol. Trop. 59 (1: 129-136. Epub 2011 March 01.

  12. Volutidae (Mollusca: Gastropoda) of the Lakhra Formation (Earliest Eocene, Sindh, Pakistan): systematics, biostratigraphy and paleobiogeography.

    Science.gov (United States)

    Merle, Didier; Pacaud, Jean-Michel; Métais, Grégoire; Bartolini, Annachiara; Lashari, Rafiq A; Brohi, Imdad A; Solangi, Sarfraz H; Marivaux, Laurent; Welcomme, Jean-Loup

    2014-06-27

    The paleobiodiversity of the Volutidae (Mollusca: Gastropoda) of the Ranikot Group (Sindh, Pakistan) and particularly of the Lakhra Formation (SBZ 5 biozone, Earliest Eocene), is reconsidered on the basis of new material collected during recent field trips. Ten new species are described (Mitreola brohii sp. nov., Lyrischapa vredenburgi sp. nov., L. brevispira sp. nov., Athleta (Volutopupa) citharopsis sp. nov., A. (Volutocorbis) lasharii sp. nov., Volutilithes welcommei sp. nov., V. sindhiensis sp. nov., Pseudaulicina coxi sp. nov., Sindhiluta lakhraensis sp. nov. and Pakiluta solangii sp. nov.) and one species is in open nomenclature (Lyria sp.). Three new genera are described: Lyriopsis gen. nov. [Volutinae, ?Lyriini, type species: Lyriopsis cossmanni (Vredenburg, 1923)], Sindhiluta gen. nov. [Volutilithinae, type species: Sindhiluta lakhraensis n. sp.] and Pakiluta gen. nov. [?Volutodermatinae, type species: Pakiluta solangii n. sp.]. Two new combinations are proposed: Lyriopsis cossmanni (Vredenburg, 1923) comb. nov. and Athleta (Volutopupa) intercrenatus (Cossmann & Pissarro, 1909) comb. nov. Lectotypes are designated for Lyria cossmanni Vredenburg, 1923, L. feddeni Vredenburg, 1923, Volutospina noetlingi Cossmann & Pissarro, 1909, V. intercrenata Cossmann & Pissarro, 1909 and Athleta (Volutocorbis) victoriae Vredenburg, 1923. With 21 species, this volutid fauna is the most diverse recorded from the Tethys Ocean during Earliest Eocene time. The assemblage is characterized by a strong turnover marked by regional speciation and the appearance of many western Tethyan invaders. Although at the species level, the assemblage documents a strong provincialism, at the genus level, the high number of shared genera between Eastern Tethyan and Old World Tethyan realms begins a phase of long-term homogeneity of volutid assemblages from the Tethyan paleobiogeographic province.

  13. The Complete Sequence of the Mitochondrial Genome of the Chamberednautilus (Mollusca: Cephalopoda)

    Energy Technology Data Exchange (ETDEWEB)

    Boore, Jeffrey L.

    2005-12-01

    Background: Mitochondria contain small genomes that arephysically separate from those of nuclei. Their comparison serves as amodel system for understanding the processes of genome evolution.Although complete mitochondrial genome sequences have been reported formore than 600 animals, the taxonomic sampling is highly biased towardvertebrates and arthropods, leaving much of the diversity yetuncharacterized. Results: The mitochondrial genome of a cephalopodmollusk, the Chambered Nautilus, is 16,258 nts in length and 59.5 percentA+T, both values that are typical of animal mitochondrial genomes. Itcontains the 37 genes that are typical for animal mtDNAs, with 15 on oneDNA strand and 22 on the other. The arrangement of these genes can bederived from that of the distantly related Katharina tunicata (Mollusca:Polyplacophora) by a switch in position of two large blocks of genes andtranspositions of four tRNA genes. There is strong skew in thedistribution of nucleotides between the two strands. There are an unusualnumber of non-coding regions and their function, if any, is not known;however, several of these demark abrupt shifts in nucleotide skew,suggesting that they may play roles in transcription and/or replication.One of the non-coding regions contains multiple repeats of a tRNA-likesequence. Some of the tRNA genes appear to overlap on the same strand,but this could be resolved if the polycistron were cleaved at thebeginning of the downstream gene, followed by polyadenylation of theproduct of the upstream gene to form a fully paired structure.Conclusions: Nautilus sp. mtDNA contains an expected gene content thathas experienced few rearrangements since the evolutionary split betweencephalopods and polyplacophorans. It contains an unusual number ofnon-coding regions, especially considering that these otherwise often aregenerated by the same processes that produce gene rearrangements. Thisappears to be yet another case where polyadenylation of mitochondrialtRNAs restores

  14. Comparação dos caldos selenito cistina, tetrationato Muller-Kauffmann e Rappaport-Vassiliadis no isolamento de Salmonella Typhimurium

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    L.G. Ávila

    2012-06-01

    Full Text Available Three selective enrichment broths - selenite cystine (SC, Muller-Kauffmann tetrathionate (MKT and Rappaport-Vassiliadis (RV - were compared, for Salmonella Typhimurium isolation from rectal swabs of a calf experimentally infected. The bacteriological procedure involved pre-enrichment in Hajna-GN broth (only for the samples inoculated in RV broth, selective enrichment (SC, MKT and RV broths, culture in modified brilliant green agar (BGA, presumptive biochemistry tests (using triple-sugar-iron agar and lysine-agar and slide agglutination test with poli-O and poli-H Salmonella antisera. SC and MKT broths were more efficient in the isolation of Salmonella Typhimurium (12 positive samples, whereas RV broth had a lower efficiency in the microbiological isolation (ten positive samples.

  15. First record of Stibarobdella moorei (Annelida, Hirudinea, Piscicolidae) a marine leech parasitizing Octopus bimaculatus (Mollusca: Octopodidae) from the Mexican Pacific coast

    OpenAIRE

    López-Peraza D. J.; Hernández-Rodríguez M.; Barón-Sevilla B.; Bückle-Ramírez L. F.; Grano-Maldonado M. I.

    2017-01-01

    The occurrence of the parasitic marine leech Stibarobdella moorei (Oka, 1910) (Hirudinea: Piscicolidae) along the northwest Mexican Pacific coast is described for the first time. This ectoparasite was collected from the skin of the Octopus bimaculatus (Verril, 1983) (Mollusca: Octopodidae). Stibarobdella loricata (Hardig, 1924) is synonymized with S. moorei as this species resembles other species of the genus based on tubercle patterns and the presence of papillae and a marginal fringe on the...

  16. Nervous system development in the Pacific oyster, Crassostrea gigas (Mollusca: Bivalvia).

    Science.gov (United States)

    Yurchenko, Olga V; Skiteva, Olga I; Voronezhskaya, Elena E; Dyachuk, Vyacheslav A

    2018-01-01

    have not been observed previously in molluscs. Finally, we performed a morphology-based comparative analysis of neuronal structures among bivalve, conchiferan, and aculiferan species. We described the development of the nervous system during the larval development in Crassostrea gigas . These data greatly advance the currently limited understanding of neurodevelopment in bivalves and mollusks, which has hampered the generation of a ground pattern reconstruction of the last common ancestor of Mollusca. Our morphological data support phylogenomic data indicating a closer Bivalvia-Gastropoda sister group relationship than the Bivalvia-Scaphopoda (Diasoma) group relationship.

  17. Comparative Study on the Adaptation and Growth Dynamics of the Helix pomatia and Helix aspersa Muller Terrestrial Snails Under Different Feeding Regimes

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    Adrian Toader-Williams

    2010-05-01

    Full Text Available We used Helix pomatia and Helix aspersa species and measure their growth as the snails were approaching the hibernation season. Helix pomatia 2yo shown a decrease in weight while being raised in enclosed parcels of 4sqm the younger Helix pomatia 1yo as well as Helix aspersa Muller demonstrated the ability to adapt relatively fast to the same conditions. We established 5 experimental lots in a Helix pomatia farm, GPS coordinates N46.606040 E23.599950. Control lot contained Taraxacum officinales, Sonchus oleraceus, Equisetum arvense and Atriplex hortensis, wild flora found within the farm. The other lots contained the same plants as the control lot plus different combinations of imported plants from other areals. The H. pomatia 2yo weight decreased in the control lot by a mean of -3.86% while H. aspersa 1yo marked an increase of +16.89% in the same lot during the same period. The lot containing lupinus polyphyllus delivered snails with weight gain of +24.66% for H. pomatia 2yo and an increase of only +1.98% for H. aspersa 1yo. As a contrast, H. pomatia 2yo gained only +7.72% while H. aspersa 1yo gained +28.89%, in the lot containing Lavanda officinalis, Foeniculum vulgare and Hyssopus officinalis among the other plants.

  18. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda in the Museum für Naturkunde, Berlin

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    Abraham Breure

    2013-03-01

    Full Text Available The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Z. quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = O. bensoni (Reeve, 1849; Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789; Porphyrobaphe (Myiorthalicus dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848; Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909; Orthalicus (Laeorthalicus reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821; Bulimus (Eurytus corticosus Sowerby III, 1895 = Plekocheilus (Eurytus stuebeli Martens, 1885. The taxon Bulimus (Eudioptus psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007 and a partial list of letters present in the correspondence archives.

  19. Comunidades de quitones (Mollusca: Polyplacophora de la Bahía de La Paz, Baja California Sur, México

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    Cedar I García Ríos

    2007-03-01

    Full Text Available A las ocho especies de poliplacóforos registradas en Bahía de la Paz, Baja California Sur, México, o cerca de ella, agregamos a Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata y Acanthochitona arragonites. El análisis de las comunidades estudiadas usando técnicas de ordenación sugiere que podría relacionarse la exposición al oleaje con la riqueza y la diversidad de especies. La comunidad recolectada en condiciones intermedias de exposición al oleaje presentó mayor número de especies y mayor diversidad de acuerdo con el índice de Shannon.Polyplacophoran communities (Mollusca: Polyplacophora at Bahía de La Paz, Baja California Sur, México. Eight species of polyplacophorans have been reported from La Bahía de la Paz, Baja California Sur, Mexico. We add Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata and Acanthochitona arragonites, increasing the known number of species to 15. Ordination analysis of five chiton communities at the site suggests a correlation of wave exposure to species composition and diversity: communities with intermediate wave exposure have more species (richness and higher diversity (Shannon’s index. Rev. Biol. Trop. 55 (1: 177-182. Epub 2007 March. 31.

  20. Biochemical profile of Achatina fulica (Mollusca: Gastropoda) after infection by different parasitic loads of Angiostrongylus cantonensis (Nematoda, Metastrongylidae).

    Science.gov (United States)

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Amaral, Ludimila Santos; Mota, Esther Maria; Maldonado Júnior, Arnaldo; Pinheiro, Jairo; Garcia, Juberlan

    2015-01-01

    The effect of experimental infection by different parasitic loads of Angiostrongylus cantonensis (Nematode, Metastrongylidae) on the activities of the aminotransferases and concentration of total proteins, uric acid and urea in the hemolymph of Achatina fulica (Mollusca, Gastropoda) were investigated. There was a significant decrease in the concentration of total proteins in the exposed snails to 5000 or more larvae. This change was accompanied by an increase in the concentrations of urea and uric acid in the hemolymph, suggesting a higher rate of deamination of the amino acids. Besides this, variations in the activities of the aminotransferases were also observed, with the highest values recorded in the groups exposed to greater parasite load. These results suggest an increase in the use of total proteins, since there was increased formation of nitrogenous catabolites, in conformity with an increase in the aminotransferase activities. Infection was verified by the fact that L3 larvae recovered from the snails was proportion to the exposure dose of L1 larvae. Histopathological results also indicated presence of an inflammatory cell infiltrate, favoring an increase of both transaminases. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Annotated type catalogue of the Orthalicoidea (Mollusca, Gastropoda) in the Museum für Naturkunde, Berlin.

    Science.gov (United States)

    Breure, Abraham S H

    2013-01-01

    The type status is described of 96 taxa classified within the superfamily Orthalicoidea and present in the Mollusca collection of the Museum für Naturkunde der Humboldt-Universität zu Berlin. Lectotypes are designated for the following taxa: Orthalicus elegans Rolle, 1895; Bulimus maranhonensis Albers, 1854; Orthalicus nobilis Rolle, 1895; Orthalichus tricinctus Martens, 1893. Orthalicus sphinx tresmariae is introduced as new name for Zebra sphinx turrita Strebel, 1909, not Zebra quagga turrita Strebel, 1909. The following synonyms are established: Zebra crosseifischeri Strebel, 1909 = Orthalicus princeps fischeri Martens, 1893; Orthalicus isabellinus Martens, 1873 = Orthalicus bensoni (Reeve, 1849); Zebra zoniferus naesiotes Strebel, 1909 = Orthalicus undatus (Bruguière, 1789); Porphyrobaphe (Myiorthalicus) dennisoni pallida Strebel, 1909 = Hemibulimus dennisoni (Reeve, 1848); Zebra delphinus pumilio Strebel, 1909 = Orthalicus delphinus (Strebel, 1909); Orthalicus (Laeorthalicus) reginaeformis Strebel, 1909 = Corona perversa (Swainson, 1821); Bulimus (Eurytus) corticosus Sowerby III, 1895 = Plekocheilus (Eurytus) stuebeli Martens, 1885. The taxon Bulimus (Eudioptus) psidii Martens, 1877 is now placed within the family Sagdidae, tentatively in the genus Platysuccinea. Appendices are included with an index to all the types of Orthalicoidea extant (including those listed by Köhler 2007) and a partial list of letters present in the correspondence archives.

  2. ON THE PALEOFAUNA INVERTEBRATES (MOLLUSCA, ARTROPODA; INSECTA OF DIATOMITE DEPOSITS OF SHAMB–1 LOCALITY (SISIAN SUITE, EARLY PLEISTOCENE, ARMENIA

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    М. A. Маrjanyan

    2016-01-01

    Full Text Available Aim. The study of fossil insects from diatomaceous sediments of Shamb-1 locality of Sisian Suite (Early Pleistocene. The collection of fossils plants and animals of Institute of Botany of NAS RA and authors' findings served as material for study.Methods. The material is processed and prepared for study by conventional methods in paleontology for prints and fossils of insects from diatomaceous sediments. There are 654 samples studied: 2 samples were with mollusks’ imprints and 652 samples with imprints of insects, from which preserved marks on 291samples allowed to identify them up to order, family, genus and species.Results. The studied material refers to the Mollusca and Arthropoda (Insecta types. Insects are represented by species of orders Orthoptera (2 fam., Homoptera (1 fam., Heteroptera (2 fam., Coleoptera (15 fam., Hymenoptera (2 fam., Diptera (1 fam.. Coleopteras dominate among them and are presented with following species of the family – Carabidae, Dytiscidae, Hydrophilidae, Histeridae, Staphylinidae, Silphidae, Elateridae, Buprestidae, Lampyridae, Scarabaeidae, Chrysomelidae, Tenebrionidae, Coccinellidae, Cerambycidae, Curculionidae.Main conclusions. An analysis of the taxonomic composition of paleofauna was done, which corresponds to the recent fauna and with considering modern ecological characteristics of systematical groups and species. In the investigated location of Shamb-1 a version is suggested about the palaeolandscapes and palaeoclimate in the Early Pleistocene.

  3. Evaluation of Accessory Lacrimal Gland in Muller's Muscle Conjunctival Resection Specimens for Precursor Cell Markers and Biological Markers of Dry Eye Disease.

    Science.gov (United States)

    Ali, Marwan; Shah, Dhara; Pasha, Zeeshan; Jassim, Sarmad H; Jassim Jaboori, Assraa; Setabutr, Pete; Aakalu, Vinay K

    2017-04-01

    The accessory lacrimal glands (ALGs) are an understudied component of the tear functional unit, even though they are important in the development of dry eye syndrome (DES). To advance our understanding of aging changes, regenerative potential, and histologic correlates to human characteristics, we investigated human ALG tissue from surgical samples to determine the presence or absence of progenitor cell markers and lacrimal epithelial markers and to correlate marker expression to relevant patient characteristics. ALG tissues obtained from Muller's muscle conjunctival resection (MMCR) specimens were created using tissue microarrays (TMAs). Immunofluorescence staining of MMCR sections was performed using primary antibodies specific to cell protein markers. Cell marker localization in TMAs was then assessed by two blinded observers using a standardized scoring system. Patient characteristics including age, race, and status of ocular surface health were then compared against expression of stem cell markers. Human ALG expressed a number of epithelial markers, and in particular, histatin-1 was well correlated with the expression of epithelial markers and was present in most acini. In addition, we noted the presence of precursor cell markers nestin, ABCG2, and CD90 in ALG tissue. There was a decrease in precursor cell marker expression with increasing age. Finally, we noted that a negative association was present between histatin-1 expression and DES. Thus, we report for the first time that human ALG tissues contain precursor marker-positive cells and that this marker expression may decrease with increasing age. Moreover, histatin-1 expression may be decreased in DES. Future studies will be performed to use these cell markers to isolate and culture lacrimal epithelial cells from heterogeneous tissues, determine the relevance of histatin-1 expression to DES, and isolate candidate precursor cells from ALG tissue.

  4. Reduction of the duration of the natural dead time of a 4 {pi} gas ionization counter operating in geiger-muller; Reduction de la duree de l'etat d'insensibilite naturelle d'un compteur a ionisation gazeuse de geometrie 4 {pi} travaillant en regime de Geiger-Muller

    Energy Technology Data Exchange (ETDEWEB)

    Becker, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires, Departement d' Electronique Generale, Laboratoire de Mesure des Radioelements

    1967-07-01

    It Is only possible to benefit from the 100 per cent efficiency of a 4 {pi} gas-ionisation detector operating in the Geiger-Muller regime (an efficiency which always appears difficult to attain in other detectors) if, one is able: - on the one hand to reduce considerably - on the other hand to fix very precisely the length at the real dead time of the system operating in the above conditions. Taking into account both the phenomena characteristic of the discharge in the regime under consideration, phenomena whose properties are described, and the geometrical conditions depending on the operation over a solid angle of 4 {pi}, it is shown that with an exterior electronic system for cutting off the discharge for example in 30 nanoseconds, absolute 4 {pi} G.M. measurements would become competitive with those now carried out almost in proportional conditions. Measurement results on sources of 5 x 10{sup 3} emissions per second maximum obtained by the use of a system for which the interval between the passage of a particle and the moment when the device has been made insensitive is still 60 nanoseconds have made it possible to confirm these statements. (author) [French] De l'efficacite de 100 pour cent du detecteur a ionisation gazeuse travaillant en regime de Geiger-Muller en geometrie 4 {pi} (efficacite toujours difficile a atteindre par d'autres detecteurs semble-t-il) on ne peut cependant beneficier que si l'on est capable: - d'une part, de reduire considerablement - d'autre part, de fixer de maniere tres precise la duree d'insensibilite reelle du systeme travaillant dans les conditions ci-dessus. Tenant compte des phenomenes propres a la decharge, dans le regime en question, phenomenes dont on rappeUto quelques caracteristiques, et des conditions geometriques propres a une detection dans un angle solide de 4 {pi} on montre qu'avec un systeme electronique de coupure externe de la decharge qui arreterait cette derniere en 30 nanosecondes par exemple, des mesures

  5. Reduction of the duration of the natural dead time of a 4 {pi} gas ionization counter operating in geiger-muller; Reduction de la duree de l'etat d'insensibilite naturelle d'un compteur a ionisation gazeuse de geometrie 4 {pi} travaillant en regime de Geiger-Muller

    Energy Technology Data Exchange (ETDEWEB)

    Becker, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires, Departement d' Electronique Generale, Laboratoire de Mesure des Radioelements

    1967-07-01

    It Is only possible to benefit from the 100 per cent efficiency of a 4 {pi} gas-ionisation detector operating in the Geiger-Muller regime (an efficiency which always appears difficult to attain in other detectors) if, one is able: - on the one hand to reduce considerably - on the other hand to fix very precisely the length at the real dead time of the system operating in the above conditions. Taking into account both the phenomena characteristic of the discharge in the regime under consideration, phenomena whose properties are described, and the geometrical conditions depending on the operation over a solid angle of 4 {pi}, it is shown that with an exterior electronic system for cutting off the discharge for example in 30 nanoseconds, absolute 4 {pi} G.M. measurements would become competitive with those now carried out almost in proportional conditions. Measurement results on sources of 5 x 10{sup 3} emissions per second maximum obtained by the use of a system for which the interval between the passage of a particle and the moment when the device has been made insensitive is still 60 nanoseconds have made it possible to confirm these statements. (author) [French] De l'efficacite de 100 pour cent du detecteur a ionisation gazeuse travaillant en regime de Geiger-Muller en geometrie 4 {pi} (efficacite toujours difficile a atteindre par d'autres detecteurs semble-t-il) on ne peut cependant beneficier que si l'on est capable: - d'une part, de reduire considerablement - d'autre part, de fixer de maniere tres precise la duree d'insensibilite reelle du systeme travaillant dans les conditions ci-dessus. Tenant compte des phenomenes propres a la decharge, dans le regime en question, phenomenes dont on rappeUto quelques caracteristiques, et des conditions geometriques propres a une detection dans un angle solide de 4 {pi} on montre qu'avec un systeme electronique de coupure externe de la decharge qui arreterait cette derniere en 30

  6. Molecular phylogenetic analysis supports a Gondwanan origin of the Hyriidae (Mollusca: Bivalvia: Unionida) and the paraphyly of Australasian taxa.

    Science.gov (United States)

    Graf, Daniel L; Jones, Hugh; Geneva, Anthony J; Pfeiffer, John M; Klunzinger, Michael W

    2015-04-01

    The freshwater mussel family Hyriidae (Mollusca: Bivalvia: Unionida) has a disjunct trans-Pacific distribution in Australasia and South America. Previous phylogenetic analyses have estimated the evolutionary relationships of the family and the major infra-familial taxa (Velesunioninae and Hyriinae: Hyridellini in Australia; Hyriinae: Hyriini, Castaliini, and Rhipidodontini in South America), but taxon and character sampling have been too incomplete to support a predictive classification or allow testing of biogeographical hypotheses. We sampled 30 freshwater mussel individuals representing the aforementioned hyriid taxa, as well as outgroup species representing the five other freshwater mussel families and their marine sister group (order Trigoniida). Our ingroup included representatives of all Australian genera. Phylogenetic relationships were estimated from three gene fragments (nuclear 28S, COI and 16S mtDNA) using maximum parsimony, maximum likelihood, and Bayesian inference, and we applied a Bayesian relaxed clock model calibrated with fossil dates to estimate node ages. Our analyses found good support for monophyly of the Hyriidae and the subfamilies and tribes, as well as the paraphyly of the Australasian taxa (Velesunioninae, (Hyridellini, (Rhipidodontini, (Castaliini, Hyriini)))). The Hyriidae was recovered as sister to a clade comprised of all other Recent freshwater mussel families. Our molecular date estimation supported Cretaceous origins of the major hyriid clades, pre-dating the Tertiary isolation of South America from Antarctica/Australia. We hypothesize that early diversification of the Hyriidae was driven by terrestrial barriers on Gondwana rather than marine barriers following disintegration of the super-continent. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Abyssal fauna of the UK-1 polymetallic nodule exploration area, Clarion-Clipperton Zone, central Pacific Ocean: Mollusca.

    Science.gov (United States)

    Wiklund, Helena; Taylor, John D; Dahlgren, Thomas G; Todt, Christiane; Ikebe, Chiho; Rabone, Muriel; Glover, Adrian G

    2017-01-01

    We present the first DNA taxonomy publication on abyssal Mollusca from the Clarion-Clipperton Zone (CCZ), central Pacific ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise 'AB01' to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration area 'UK-1' in the eastern CCZ. This is the third paper in a series to provide regional taxonomic data for a region that is undergoing intense deep-sea mineral exploration for high-grade polymetallic nodules. Taxonomic data are presented for 21 species from 42 records identified by a combination of morphological and genetic data, including molecular phylogenetic analyses. These included 3 heterodont bivalves, 5 protobranch bivalves, 4 pteriomorph bivalves, 1 caudofoveate, 1 monoplacophoran, 1 polyplacophoran, 4 scaphopods and 2 solenogastres. Gastropoda were recovered but will be the subject of a future study. Seven taxa matched published morphological descriptions for species with deep Pacific type localities, and our sequences provide the first genetic data for these taxa. One taxon morphologically matched a known cosmopolitan species but with a type locality in a different ocean basin and was assigned the open nomenclature ' cf ' as a precautionary approach in taxon assignments to avoid over-estimating species ranges. One taxon is here described as a new species, Ledella knudseni sp. n. For the remaining 12 taxa, we have determined them to be potentially new species, for which we make the raw data, imagery and vouchers available for future taxonomic study. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections.

  8. Abyssal fauna of the UK-1 polymetallic nodule exploration area, Clarion-Clipperton Zone, central Pacific Ocean: Mollusca

    Directory of Open Access Journals (Sweden)

    Helena Wiklund

    2017-10-01

    Full Text Available We present the first DNA taxonomy publication on abyssal Mollusca from the Clarion-Clipperton Zone (CCZ, central Pacific ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE environmental survey cruise ‘AB01’ to the UK Seabed Resources Ltd (UKSRL polymetallic-nodule exploration area ‘UK-1’ in the eastern CCZ. This is the third paper in a series to provide regional taxonomic data for a region that is undergoing intense deep-sea mineral exploration for high-grade polymetallic nodules. Taxonomic data are presented for 21 species from 42 records identified by a combination of morphological and genetic data, including molecular phylogenetic analyses. These included 3 heterodont bivalves, 5 protobranch bivalves, 4 pteriomorph bivalves, 1 caudofoveate, 1 monoplacophoran, 1 polyplacophoran, 4 scaphopods and 2 solenogastres. Gastropoda were recovered but will be the subject of a future study. Seven taxa matched published morphological descriptions for species with deep Pacific type localities, and our sequences provide the first genetic data for these taxa. One taxon morphologically matched a known cosmopolitan species but with a type locality in a different ocean basin and was assigned the open nomenclature ‘cf’ as a precautionary approach in taxon assignments to avoid over-estimating species ranges. One taxon is here described as a new species, Ledella knudseni sp. n. For the remaining 12 taxa, we have determined them to be potentially new species, for which we make the raw data, imagery and vouchers available for future taxonomic study. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections.

  9. Evaluation of uptake and chronic toxicity of virgin polystyrene microbeads in freshwater zebra mussel Dreissena polymorpha (Mollusca: Bivalvia).

    Science.gov (United States)

    Magni, Stefano; Gagné, François; André, Chantale; Della Torre, Camilla; Auclair, Joëlle; Hanana, Houda; Parenti, Camilla Carla; Bonasoro, Francesco; Binelli, Andrea

    2018-08-01

    Microplastics (MPs), plastic debris smaller than 5mm, are widely found in both marine and freshwater ecosystems. However, few studies regarding their hazardous effects on inland water organisms, have been conducted. For this reason, the aim of our research was the evaluation of uptake and chronic toxicity of two mixtures (MIXs) of virgin polystyrene microbeads (PMs) of 10μm and 1μm in size (MIX 1, with 5×10 5 of 1μmsizePMs/L and 5×10 5 of 10μmsizePMs/L, and MIX 2 with 2×10 6 of 1μmsizePMs/L and 2×10 6 of 10μmsizePMs/L) on freshwater zebra mussel Dreissena polymorpha (Mollusca: Bivalvia) during 6 exposure days. The PM uptake in the mussel body and hemolymph was assessed using confocal microscopy, while the chronic toxicity of PMs was evaluated on exposed mussels using a comprehensive battery of biomarkers of cellular stress, oxidative damage and neuro- genotoxicity. Confocal microscopy analyses showed that MPs concentrated in the gut lumen of exposed mussels, absorbed and transferred firstly in the tissues and then in the hemolymph. The results revealed that PMs do not produce oxidative stress and genetic damage, with the exception of a significant modulation of catalase and glutathione peroxidase activities in mussels exposed to MIX 1. Regarding neurotoxicity, we observed only a significant increase of dopamine concentration in mussels exposed to both MIXs, suggesting a possible implication of this neurotransmitter in an elimination process of accumulated PMs. This research represents a first study about the evaluation of virgin MP toxicity in zebra mussel and more research is warranted concerning the long term neurological effects of virgin MPs. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  10. First record of Stibarobdella moorei (Annelida, Hirudinea, Piscicolidae a marine leech parasitizing Octopus bimaculatus (Mollusca: Octopodidae from the Mexican Pacific coast

    Directory of Open Access Journals (Sweden)

    López-Peraza D. J.

    2017-12-01

    Full Text Available The occurrence of the parasitic marine leech Stibarobdella moorei (Oka, 1910 (Hirudinea: Piscicolidae along the northwest Mexican Pacific coast is described for the first time. This ectoparasite was collected from the skin of the Octopus bimaculatus (Verril, 1983 (Mollusca: Octopodidae. Stibarobdella loricata (Hardig, 1924 is synonymized with S. moorei as this species resembles other species of the genus based on tubercle patterns and the presence of papillae and a marginal fringe on the oral sucker. The present finding throws new light on the biodiversity and host preference of the ectoparasite and suggests a successful migration to unusual host. The coast of the Pacific Ocean, particularly in the Bay of Los Angeles, Baja California, Mexico is a new geographical distribution area for S. moorei, and O. bimaculatus is a new host reported for this leech. The morphology of this ectoparasite is briefly described.

  11. A massive ingression of the alien species Mytilus edulis L. (Bivalvia: Mollusca into the Mediterranean Sea following the Costa Concordia cruise-ship disaster

    Directory of Open Access Journals (Sweden)

    E. CASOLI

    2016-03-01

    Full Text Available The Costa Concordia cruise-ship disaster occurred just off the coast of Italy on January 13th, 2012, and entailed the largest marine salvage operation in history. The salvage employed vessels from different European harbours, providing an unexpected means for transporting alien species into the Mediterranean. In this work we identified mussel species using fragments length polymorphism of a nuclear locus and report the first evidence of the transport of the blue mussel, Mytilus edulis Linnaeus, 1758 (Bivalvia: Mollusca, into the Mediterranean Sea, as a part of the fouling community of the hull of an accommodation barge arrived from a NE Atlantic location in October 2012. Furthermore, we describe the rapid growth of this species, under the ASV Pioneer, until its almost total extinction during the summer of 2013, which left a covering of mussel shells on the underlying Posidonia oceanica (Linnaeus Delile, 1813. meadow. This high mortality rate indicated that M. edulis had been exposed to high stress conditions, probably due to different salinity, temperature, and oligotrophic conditions from its place of origin, and there was no spawning event or known settlement on the nearest infralittoral natural habitats. This event reminds us of how the Mediterranean Sea is constantly under alien-species pressure, due to human activities.

  12. The influence of fish cage culture on δ{sup 13}C and δ{sup 15}N of filter-feeding Bivalvia (Mollusca)

    Energy Technology Data Exchange (ETDEWEB)

    Benedito, E.; Takeda, A.M., E-mail: eva@nupelia.uem.br [Universidade Estadual de Maringa (UEM), PR (Brazil). Nucleo de Pesquisas em Limnologia, Ictiologia e Aquicultura; Figueroa, L. [Universidade Estadual de Maringa (UEM), PR (Brazil). Pos-Graduacao em Ecologia de Ambientes Aquaticos Continentais; Manetta, GI. [Universidade Estadual de Maringa (UEM), PR (Brazil). Pos-Graduacao em Biologia Comparada

    2013-11-15

    The objective of this study was to evaluate the effect of Oreochromis niloticus cage culture promoted variations in the δ{sup 13}C and δ{sup 15}N in Corbicula fluminea (Mollusca; Bivalvia) and in the sediment of an aquatic food web. Samples were taken before and after net cage installation in the Rosana Reservoir (Paranapanema River, PR-SP). Samples of specimens of the bivalve filter C. fluminea and samples of sediment were collected using a modified Petersen grab. All samples were dried in an oven (60 °C) for 72 hours, macerated to obtain homogenous fine powders and sent for carbon (δ{sup 13}C) and nitrogen (δ{sup 15}N) isotopic value analysis in a mass spectrometer. There were significant differences in the δ{sup 13}C and δ{sup 15}N values of the invertebrate C. fluminea between the beginning and the end of the experiment. There were no differences between the δ{sup 13}C and δ{sup 15}N values of sediment. These results indicate that the installation of fish cage culture promoted impacts in the isotopic composition of the aquatic food web organisms, which could exert influence over the native species and the ecosystem. (author)

  13. (Lamark) (Mollusca: Bivalvia)

    African Journals Online (AJOL)

    Figure 2 Mean monthly surface water temperature and salinity values ..... Excluding the effect of the flood, the progression of the .... Growth and metabolism of Mactra lilacea. Abstract ... tolerance and osmoregulation in some estuarine bivalves.

  14. The linked units of 5S rDNA and U1 snDNA of razor shells (Mollusca: Bivalvia: Pharidae).

    Science.gov (United States)

    Vierna, J; Jensen, K T; Martínez-Lage, A; González-Tizón, A M

    2011-08-01

    The linkage between 5S ribosomal DNA and other multigene families has been detected in many eukaryote lineages, but whether it provides any selective advantage remains unclear. In this work, we report the occurrence of linked units of 5S ribosomal DNA (5S rDNA) and U1 small nuclear DNA (U1 snDNA) in 10 razor shell species (Mollusca: Bivalvia: Pharidae) from four different genera. We obtained several clones containing partial or complete repeats of both multigene families in which both types of genes displayed the same orientation. We provide a comprehensive collection of razor shell 5S rDNA clones, both with linked and nonlinked organisation, and the first bivalve U1 snDNA sequences. We predicted the secondary structures and characterised the upstream and downstream conserved elements, including a region at -25 nucleotides from both 5S rDNA and U1 snDNA transcription start sites. The analysis of 5S rDNA showed that some nontranscribed spacers (NTSs) are more closely related to NTSs from other species (and genera) than to NTSs from the species they were retrieved from, suggesting birth-and-death evolution and ancestral polymorphism. Nucleotide conservation within the functional regions suggests the involvement of purifying selection, unequal crossing-overs and gene conversions. Taking into account this and other studies, we discuss the possible mechanisms by which both multigene families could have become linked in the Pharidae lineage. The reason why 5S rDNA is often found linked to other multigene families seems to be the result of stochastic processes within genomes in which its high copy number is determinant.

  15. Megafauna of the UKSRL exploration contract area and eastern Clarion-Clipperton Zone in the Pacific Ocean: Annelida, Arthropoda, Bryozoa, Chordata, Ctenophora, Mollusca.

    Science.gov (United States)

    Amon, Diva J; Ziegler, Amanda F; Drazen, Jeffrey C; Grischenko, Andrei V; Leitner, Astrid B; Lindsay, Dhugal J; Voight, Janet R; Wicksten, Mary K; Young, Craig M; Smith, Craig R

    2017-01-01

    There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite having been the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. To predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to ABYSSLINE research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ. Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle (as well as several other pieces of equipment), the megafauna within the UK Seabed Resources Ltd exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal annelid, arthropod, bryozoan, chordate, ctenophore and molluscan megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 55 distinct morphospecies (8 Annelida, 12 Arthropoda, 4 Bryozoa, 22 Chordata, 5 Ctenophora, and 4 Mollusca) identified mostly by morphology but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat.

  16. Tolerance to air exposure of the New Zealand mudsnail Potamopyrgus antipodarum (Hydrobiidae, Mollusca as a prerequisite to survival in overland translocations

    Directory of Open Access Journals (Sweden)

    Alvaro Alonso

    2012-08-01

    Full Text Available Spreading throughout a new ecosystem is the last step of an exotic species to become invasive. In the case of invasive aquatic molluscs, tolerance to air exposure is one of the main mechanisms allowing overland translocation and spreading. The mudsnail Potamopyrgus antipodarum (Hydrobiidae, Mollusca is native to New Zealand but it has spread worldwide, invading ecosystems in Europe, Australia, America and Asia. The aim of our study is to assess mudsnail tolerance to air exposure, which may contribute to the successful overland translocation of this species. We conducted a laboratory experiment with four levels of air exposure (9, 18, 24 and 36 hours in a controlled climatic chamber. Snails were placed for 60 seconds in a laboratory paper filter to remove surface snail water. Then they were placed back in empty vessels during the four periods of air exposure, except the control group, which was immediately returned to water. At the end of each period of air exposure all vessels were filled with water and the cumulative mortality was monitored after 24, 96, 168 and 264 hours of rehydration. The calculated Lethal Times (i.e. the time of air exposure (in hours necessary to cause the death of 50% (LT50 or 99% (LT99 of the population and their 95% confidence limits at 24, 96, 168 and 264 hours were 28.1 (25.2–31.9, 26.9 (24.2–30.1, 25.9 (23.4–28.9 and 25.9 (23.4–28.9 hours, respectively for LT50, and 49.6 (42.7–63.3, 45.6 (39.9–56.5, 43.2 (38.0–53.0 and 43.2 (38.0–53.0 hours, respectively for LT99. Therefore an air exposure time over 43 hours caused the death of all studied individuals during all monitoring periods. Extending the monitoring period beyond 24 hours did not significantly change lethal times. Therefore, we recommend exposing fishing tools or boats at open air during at least 53 hours as a low cost measure to control mudsnail spread in early stages of invasion.

  17. Marine mollusca of oxygen isotope stages of the last 2 million years in New Zealand. Part 1, Revised generic positions and recognition of warm-water and cool-water migrants

    International Nuclear Information System (INIS)

    Beu, A.G.

    2004-01-01

    Warm-water molluscs were transported to Wanganui Basin from the northeastern North Island during Pleistocene time as planktotrophic larvae. This is not possible at present, so their occurrence in Wanganui Basin correlates with breaches of the Auckland isthmus during high sea levels. The end of Nukumaruan time is clearly defined by the extinction of 29 genera of molluscs (most only locally) during this stage, including 15 at the end. The extinction likely was caused by the initial closure of the Auckland isthmus. Migrants to Wanganui from the northeastern North Island indicate that breaches of the isthmus during interglacials commenced in oxygen isotope stage (OIS) 25, just before the mid-Pleistocene transition (MPT). Appearances of taxa from Australia at Wanganui during OIS 17-9 therefore indicate that warm-water taxa were transported to New Zealand during interglacial maxima after the MPT. The migrants provide the first molluscan biostratigraphy at the OIS scale. The Castlecliffian/Nukumaruan boundary, at the base of Ototoka tephra at Ototoka Beach, Wanganui, falls within OIS 57, with an age of c. 1.63 Ma. It is also dated at 1.63 Ma by the position with respect to the geomagnetic polarity time-scale of three chemically indistinguishable tephra in ODP core 1123. This paper presents the first results of a reassessment of the taxonomy and time ranges of the fossil marine molluscan fauna that occupied New Zealand during the last 2 m.y. (latest Pliocene-Holocene). Time ranges are compiled in oxygen isotope stages rather than in the traditional 'local' (or regional) stages in use in New Zealand. This should provide precision in time ranges of the order of 40,000-100,000 yr, rather than the 0.34-1.3 m.y. duration of New Zealand local stages of the latest Neogene (Nukumaruan, Castlecliffian, and Haweran Stages). The reassessment is aimed also, though, at providing evidence from Mollusca of climate change over this period. Much useful information on paleoclimates can be

  18. Growth of juvenile Pseudoplatystoma reticulatum and Pseudoplatystoma spp. in pond

    Directory of Open Access Journals (Sweden)

    Aline Mayra da Silva Oliveira

    2014-02-01

    Full Text Available The growth of the fish is an important factor that determines the potential of various species for economic exploitation. The aim this work was evaluates the growth juvenile cachara and hybrid grown in pond. Information was collected of weight and morphometric measures during the experimental period. Total length gain, body height gain, body width gain, weight gain, growth index, morphometric ratios and body percentage were calculated. The methodology of generalized linear models was used, considering Gamma distribution and inverse link function. The variances and averages of variables were submitted tests F of the Snedecor and Chi-Square, respectively. The hybrids gained more weight in second and third biometrics, beyond of presented greater total length gain and body percentage. The head size and head width of cacharas were higher in three biometrics. The variances of hybrids were higher in the second and third biometrics. The hybrids presented better performance, but lesser standardization for traits evaluated than pure specie, confirming the need development genetic improvement programs that performs pure species selection for increased commercial production.

  19. Pectinoidea (Mollusca: Bivalvia) from Iceland

    NARCIS (Netherlands)

    Dijkstra, H.H.; Waren, A.; Gudmundsson, G.

    2009-01-01

    The Icelandic pectinoid fauna is reviewed, based on material from the benthic survey programme BIOICE and 17 species are recorded. Similipecten oskarssoni is proposed as a replacement name for Pecten groenlandicus var. minor Locard, 1898 (Propeamussiidae), which is considered a valid species.

  20. Fauna Europaea: Mollusca – Bivalvia

    Directory of Open Access Journals (Sweden)

    Rafael Araujo

    2015-07-01

    European freshwater bivalves belong to the Orders Unionoida and Cardiida. All the European unionoids are included in the superfamily Unionoidea, the freshwater mussels or naiads. The European cardiids belong to the following three superfamilies: Cardioidea, Cyrenoidea and Dreissenoidea. Among the Unionoidea there are the most imperilled animal groups on the planet while the Cardioidea includes the cosmopolitan genus Pisidium, the Cyrenoidea the Asiatic clam (Corbicula fluminea and the Dreissenoidea the famous invasive zebra mussel (Dreissena polymorpha. Basic information is summarized on their taxonomy and biology. Tabulations include a complete list of the current estimated families, genera and species.

  1. Evaluation of the levels of Br, Cl, K, Mg, Mn and V in Perna perna mussels (Linnaeus, 1758: Mollusca Bivalvia) collected in the coast of Sao Paulo state, Brazil; Avaliacao dos teores de Br, Cl, K, Mg, Mn e V em mexilhoes Perna perna (Linnaeus, 1758: Mollusca Bivalvia) coletados no litoral do estado de Sao Paulo, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Daniele

    2012-07-01

    The coastal environment has been heavily altered by multiple environmental impacts of human activities, such as disposal of sewage from urban areas, the release of numerous chemical industries, agriculture and the flow of vessels, which can lead to accidental spills of oil and oil products, fuels and other products transported by sea. In this context, a means of determining concentrations of these potentially toxic substances in the sea water is the biomonitoring by means of different types of bivalves, which have been used by various researchers, in Brazil and other countries. With regard to bivalve mollusks, particularly mussels, their use in monitoring the marine contamination is mainly due to their wide geographic distribution, sessile habit and ability to concentrate toxic metals to 102-105 times in relation to the concentrations detected in water. In the present study, we employed the passive biomonitoring using the Perna perna bivalve mollusk with respect to the elements Br, Cl, K, Mg, Mn and V. These elements were chosen since they can be determined by INAA method (Instrumental Neutron Activation Analysis), by means of short irradiation which provides faster analyzes and also due to their importance from the standpoint of environmental or nutritional studies. The aim of this study was to evaluate the content of Br, Cl, K, Mg, Mn and V in samples of Perna perna mussels (Linnaeus, 1758: Mollusca, Bivalvia) collected in coastal regions of Sao Paulo subject to anthropogenic contamination (Ponta de Itaipu and Palmas Island, in Santos), comparing the values obtained in sites potentially impacted with the values of the control site in Praia da Cocanha, in Caraguatatuba. The collection points located in Sao Paulo coast are located in the geographical areas 23 Masculine-Ordinal-Indicator 37'S - 45 Degree-Sign 24' W (Caraguatatuba) and 23 Masculine-Ordinal-Indicator 57'S - 46 Masculine-Ordinal-Indicator 20' W (Santos). The collection of organisms

  2. Evaluation of the levels of Br, Cl, K, Mg, Mn and V in Perna perna mussels (Linnaeus, 1758: Mollusca Bivalvia) collected in the coast of Sao Paulo state, Brazil; Avaliacao dos teores de Br, Cl, K, Mg, Mn e V em mexilhoes Perna perna (Linnaeus, 1758: Mollusca Bivalvia) coletados no litoral do estado de Sao Paulo, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Daniele

    2012-07-01

    The coastal environment has been heavily altered by multiple environmental impacts of human activities, such as disposal of sewage from urban areas, the release of numerous chemical industries, agriculture and the flow of vessels, which can lead to accidental spills of oil and oil products, fuels and other products transported by sea. In this context, a means of determining concentrations of these potentially toxic substances in the sea water is the biomonitoring by means of different types of bivalves, which have been used by various researchers, in Brazil and other countries. With regard to bivalve mollusks, particularly mussels, their use in monitoring the marine contamination is mainly due to their wide geographic distribution, sessile habit and ability to concentrate toxic metals to 102-105 times in relation to the concentrations detected in water. In the present study, we employed the passive biomonitoring using the Perna perna bivalve mollusk with respect to the elements Br, Cl, K, Mg, Mn and V. These elements were chosen since they can be determined by INAA method (Instrumental Neutron Activation Analysis), by means of short irradiation which provides faster analyzes and also due to their importance from the standpoint of environmental or nutritional studies. The aim of this study was to evaluate the content of Br, Cl, K, Mg, Mn and V in samples of Perna perna mussels (Linnaeus, 1758: Mollusca, Bivalvia) collected in coastal regions of Sao Paulo subject to anthropogenic contamination (Ponta de Itaipu and Palmas Island, in Santos), comparing the values obtained in sites potentially impacted with the values of the control site in Praia da Cocanha, in Caraguatatuba. The collection points located in Sao Paulo coast are located in the geographical areas 23 Masculine-Ordinal-Indicator 37'S - 45 Degree-Sign 24' W (Caraguatatuba) and 23 Masculine-Ordinal-Indicator 57'S - 46 Masculine-Ordinal-Indicator 20' W (Santos). The collection of organisms was performed in all

  3. ’n Vergelyking van die Mollusca-diversiteit in die Mooirivier (Noordwes-Provinsie soos gevind met opnames wat gemaak is in 1963 en weer 50 jaar later

    Directory of Open Access Journals (Sweden)

    Cornelius T. Wolmarans

    2015-02-01

    Full Text Available Die hoogste getal gedokumenteerde uitsterwings van enige belangrike taksonomiese groepword aan die Mollusca toegedig. Faktore wat hoofsaaklik hiervoor verantwoordelik is, sluitonder meer omgewingsveranderinge en antropogeniese impakte in wat tot die tot niet gaanvan die habitat aanleiding gee. Daarbenewens is die bewaringstatus van minder as 2% van dieongeveer 7000 molluskspesies wêreldwyd bekend tot dusver nog nie behoorlik geassesseernie. Die doel van die huidige ondersoek wat in 2014 uitgevoer is, was om die molluskdiversiteitvan die Mooirivier met die resultate van 1963 te vergelyk. Dit is gedoen deur ’n opnameuit te voer van die molluskdiversiteit by dieselfde lokaliteite as in 1963. Twee opnames isgemaak tydens ’n vroeë- en laatlaagvloeiperiode in 2014 by agt lokaliteite wat met dié vandie 1963-opnames ooreenstem. Die pH, elektriese geleiding (EG en temperatuur is ook byelk van die lokaliteite gemeet. Die identiteit van die 14 slakspesies wat in 1963 gevind is, hetooreengestem met 14 van die 15 in 2014. Die uitheemse indringerspesie Physa acuta is tydensdie 2014-opname vir die eerste keer in hierdie rivier gevind, waarskynlik weens ’n toename inorganiese verryking. In die 1963-opname is Burnupia mooiensis en Pisidium langlyanum by diemeeste lokaliteite gevind, en in 2014 Gyraulus connollyi en Ferrissia cawstoni. Die meeste van diemolluske uit hierdie gebied wat voorheen op rekord gestel is, is in 2014 gevind. Die pH watin 2014 ’n geringe tot aansienlike verlaging getoon het, word aan mynversuring toegeskryfen het nie ’n merkbare invloed op die molluskdiversiteit gehad nie. Die hoër elektriesegeleiding wat tydens die 2014-opname gemeet is, het vanweë die verdraagsaamheid vanvarswatermolluske in hierdie verband, ook geen verandering in die molluskdiversiteit teweeggebring nie. Die temperatuur was in die laatlaagvloei deurgaans hoër. Ondanks die feit dathierdie studies vyf dekades uitmekaar gedoen is en antropogeniese impakte

  4. Intragenomic sequence variation at the ITS1 - ITS2 region and at the 18S and 28S nuclear ribosomal DNA genes of the New Zealand mud snail, Potamopyrgus antipodarum (Hydrobiidae: mollusca)

    Science.gov (United States)

    Hoy, Marshal S.; Rodriguez, Rusty J.

    2013-01-01

    Molecular genetic analysis was conducted on two populations of the invasive non-native New Zealand mud snail (Potamopyrgus antipodarum), one from a freshwater ecosystem in Devil's Lake (Oregon, USA) and the other from an ecosystem of higher salinity in the Columbia River estuary (Hammond Harbor, Oregon, USA). To elucidate potential genetic differences between the two populations, three segments of nuclear ribosomal DNA (rDNA), the ITS1-ITS2 regions and the 18S and 28S rDNA genes were cloned and sequenced. Variant sequences within each individual were found in all three rDNA segments. Folding models were utilized for secondary structure analysis and results indicated that there were many sequences which contained structure-altering polymorphisms, which suggests they could be nonfunctional pseudogenes. In addition, analysis of molecular variance (AMOVA) was used for hierarchical analysis of genetic variance to estimate variation within and among populations and within individuals. AMOVA revealed significant variation in the ITS region between the populations and among clones within individuals, while in the 5.8S rDNA significant variation was revealed among individuals within the two populations. High levels of intragenomic variation were found in the ITS regions, which are known to be highly variable in many organisms. More interestingly, intragenomic variation was also found in the 18S and 28S rDNA, which has rarely been observed in animals and is so far unreported in Mollusca. We postulate that in these P. antipodarum populations the effects of concerted evolution are diminished due to the fact that not all of the rDNA genes in their polyploid genome should be essential for sustaining cellular function. This could lead to a lessening of selection pressures, allowing mutations to accumulate in some copies, changing them into variant sequences.                   

  5. Comunidad de moluscos asociados al mejillón verde Perna viridis (Mollusca: Bivalvia y sus relaciones tróficas en la costa norte de la Península de Araya, Estado Sucre, Venezuela

    Directory of Open Access Journals (Sweden)

    Sioliz Villafranca

    2006-12-01

    Full Text Available Perna viridis es un bivalvo procedente del Indo-Pacífico que habita en la zona intermareal y ha invadido varios ecosistemas de la costa norte del estado Sucre, Venezuela. Con la finalidad de realizar un estudio sobre las comunidades de moluscos asociadas a esta especie y sus relaciones tróficas, se llevaron a cabo muestreos bimensuales entre octubre/97 y agosto/98, en un banco natural de mejillones a dos metros de profundidad en la costa norte de la península de Araya (10°40’N -48°63’W. Los organismos fueron recolectados delimitando el área con una cuadrícula de 0.25 m². Se identificaron los organismos hasta la categoría de especies utilizando claves específicas para moluscos y bibliográficamente se les determinó categoría trófica.Se capturó un total de 1 235 individuos de P. viridis y asociados a la especie 3 163 especímenes pertenecientes al phylum Mollusca, contenidos en tres clases: Bivalvia,Gastropoda y Polyplacophora. Éstas estuvieron representadas por 50 especies correspondientes a 10 órdenes, 24 familias; para los gasterópodos se contabilizaron 25 especies, para los bivalvos 22 y tres para los poliplacóforos. Del total de las especies, 40% fueron filtradoras, 26% carnívoras, 24% herbívoras y el 10% restante presentó dos categorías.De las filtradoras las más representativas fueron: Perna perna, Musculus lateralis, Crassostrea rhizophorae y Ostrea equestris; en el grupo de los carnívoros dominaron tres especies de la familia Columbellidae:Mitrella lunata, Anachis obesa y Nitidella ocellata y para el grupo de los herbívoros destacaron dos especies de la familia Fisurellidae: Diodora cayenensis y D. minuta. Se registraron dos especies filtradoras-detritívoras, y tres especies herbívoras-filtradoras representantes del género C repidula. El alto porcentaje de filtradores sería un indicativo de que dentro de este sistema probablemente hay una mayor disponibilidad de fracciones alimenticias para este grupo

  6. Evaluation of the levels of Br, Cl, K, Mg, Mn and V in Perna perna mussels (Linnaeus, 1758: Mollusca Bivalvia) collected in the coast of Sao Paulo state, Brazil

    International Nuclear Information System (INIS)

    Seo, Daniele

    2012-01-01

    The coastal environment has been heavily altered by multiple environmental impacts of human activities, such as disposal of sewage from urban areas, the release of numerous chemical industries, agriculture and the flow of vessels, which can lead to accidental spills of oil and oil products, fuels and other products transported by sea. In this context, a means of determining concentrations of these potentially toxic substances in the sea water is the biomonitoring by means of different types of bivalves, which have been used by various researchers, in Brazil and other countries. With regard to bivalve mollusks, particularly mussels, their use in monitoring the marine contamination is mainly due to their wide geographic distribution, sessile habit and ability to concentrate toxic metals to 102-105 times in relation to the concentrations detected in water. In the present study, we employed the passive biomonitoring using the Perna perna bivalve mollusk with respect to the elements Br, Cl, K, Mg, Mn and V. These elements were chosen since they can be determined by INAA method (Instrumental Neutron Activation Analysis), by means of short irradiation which provides faster analyzes and also due to their importance from the standpoint of environmental or nutritional studies. The aim of this study was to evaluate the content of Br, Cl, K, Mg, Mn and V in samples of Perna perna mussels (Linnaeus, 1758: Mollusca, Bivalvia) collected in coastal regions of São Paulo subject to anthropogenic contamination (Ponta de Itaipu and Palmas Island, in Santos), comparing the values obtained in sites potentially impacted with the values of the control site in Praia da Cocanha, in Caraguatatuba. The collection points located in São Paulo coast are located in the geographical areas 23º 37'S - 45° 24' W (Caraguatatuba) and 23º 57'S - 46º 20' W (Santos). The collection of organisms was performed in all seasons of the year, beginning in spring 2008 and ending in winter 2009. The samples

  7. Incarnation theology versus the sacralisation of authority | Muller ...

    African Journals Online (AJOL)

    This article juxtaposed the theological theme of incarnation with quasi-religious invasions of public power structures and institutions in southern Africa, which has been described by the term sacralisation of authority. Incarnational theology as constructed on the model of the Incarnation of Jesus Christ concerns a ...

  8. Oxidative Stress-Induced Dysfunction of Muller Cells During Starvation

    DEFF Research Database (Denmark)

    Toft-Kehler, Anne Katrine; Gurubaran, Iswariyaraja Sridevi; Madsen, Claus Desler

    2016-01-01

    starvation for 24 hours. Effects of starvation and H2O2 on glutamate uptake and mitochondrial function were assessed by kinetic glutamate uptake assays and Seahorse assays, respectively. Cell survival was evaluated by cell viability assays. mRNA and protein expressions were assessed by quantitative PCR...

  9. Decoding Reed-Muller Codes beyond Half the Minimum Distance

    DEFF Research Database (Denmark)

    Heydtmann, Agnes Eileen; Jakobsen, Thomas

    1999-01-01

    vanishing when evaluated at points in $\\ff^m_2$ joint with the corresponding received bits. To obtain a list of codewords closest to the received word we need to factor $Q$ considered as an element of the quotient ring of boolean polynomials which is not a unique factorization domain. Therefore we introduce...

  10. Record Litter Size for the Bull Shark, Carcharhinus leucas (Muller ...

    African Journals Online (AJOL)

    On the morning of 25 September 2013, a large female bull shark, Carcharhinus leucas, was landed in Port Victoria, Seychelles. It had been caught on an anchored long line set the previous evening, within 100 m of the main fishing quay. The female exhibited an unusually large girth for this heavy-set species. The shark ...

  11. Pereskia aculeata Muller (Cactaceae Leaves: Chemical Composition and Biological Activities

    Directory of Open Access Journals (Sweden)

    Lucèia Fàtima Souza

    2016-09-01

    Full Text Available The aims of this work were to study the chemical composition of the essential oil from the leaves of Pereskia aculeata and to evaluate some biological activities of three leaf extracts. The phenolic content, antioxidant activity, and in vitro antimicrobial and antifungal activities were determined. The methanol extract showed antioxidant activity (EC50 7.09 mg/mL and high polyphenols content (15.04 ± 0.31 mg gallic acid equivalents (GAE/g. The petroleum ether extract exhibited potent antibacterial activity against Escherichia coli, whereas the chloroform extract showed inhibitory activity against Bacillus cereus and Staphylococcus aureus. The petroleum ether and methanol extracts were more effective in inhibiting the growth of Aspergillus versicolor. The possible cytotoxicity of extracts on neuroblastoma SH-SY5Y cancer cell line and the influence on adenylate cyclase (ADCY expression was also studied. P. aculeata chloroform extract showed antiproliferative activity with an IC50 value of 262.83 µg/mL. Treatments of SH-SY5Y neuroblastoma cells with 100 µg/mL of methanol extract significantly reduced ADCY1 expression.

  12. Didactic counter unit with Geiger-Muller tubes

    International Nuclear Information System (INIS)

    Campos, A.

    1981-01-01

    At this paper a prototype of these instruments is search for a didactic application. A block diagram to instrument, well as an operation process of it, is developed. A description of each one blocks, mentioning the characteristics, advantages and, to compare some possible solutions, is also presented. (author)

  13. Linking poverty and violence: The South African scenario | Muller ...

    African Journals Online (AJOL)

    In present-day South Africa we are daily confronted with individual or group scenes of violence in townships and 'shanty-towns' where people live in poverty. Frequently, it involves people clamouring for the redemption of the promises made to them by politicians prior to the first democratic election in 1994 – promises of a ...

  14. Pereskia aculeata Muller (Cactaceae) Leaves: Chemical Composition and Biological Activities.

    Science.gov (United States)

    Souza, Lucèia Fàtima; Caputo, Lucia; Inchausti De Barros, Ingrid Bergman; Fratianni, Florinda; Nazzaro, Filomena; De Feo, Vincenzo

    2016-09-03

    The aims of this work were to study the chemical composition of the essential oil from the leaves of Pereskia aculeata and to evaluate some biological activities of three leaf extracts. The phenolic content, antioxidant activity, and in vitro antimicrobial and antifungal activities were determined. The methanol extract showed antioxidant activity (EC50 7.09 mg/mL) and high polyphenols content (15.04 ± 0.31 mg gallic acid equivalents (GAE)/g). The petroleum ether extract exhibited potent antibacterial activity against Escherichia coli, whereas the chloroform extract showed inhibitory activity against Bacillus cereus and Staphylococcus aureus. The petroleum ether and methanol extracts were more effective in inhibiting the growth of Aspergillus versicolor. The possible cytotoxicity of extracts on neuroblastoma SH-SY5Y cancer cell line and the influence on adenylate cyclase (ADCY) expression was also studied. P. aculeata chloroform extract showed antiproliferative activity with an IC50 value of 262.83 µg/mL. Treatments of SH-SY5Y neuroblastoma cells with 100 µg/mL of methanol extract significantly reduced ADCY1 expression.

  15. Perfil de lípidos y ácidos grasos de Perna viridis, mejillón verde (Mollusca: Bivalvia en el oriente venezolano y la costa oeste de Trinidad

    Directory of Open Access Journals (Sweden)

    Tamar Koftayan

    2011-03-01

    Full Text Available Los lípidos totales fueron extraídos, identificados y cuantificados por gravimetría, mediante TLC/FID (sistema Iatroscan. Los ácidos grasos de los lípidos totales, fosfolípidos y triacilgliceroles fueron identificados y cuantificados por cromatografía de gases. Las mayores concentraciones de lípidos totales se presentaron en las muestras de Los Cedros, La Brea y Chaguaramas con valores de 7.92, 7.74 y 7.53%; respectivamente y los valores mínimos en las de La Restinga (6.08%. En la composición lípidica, las muestras de Chacopata presentaron la menor concentración de fosfolípidos (48.86% y los máximos valores de colesterol (38.87% y triacilgliceroles (12.26%, y las muestras de La Esmeralda y Río Caribe exhibieron concentraciones máximas de fosfolípidos (88.71-84.93%, respectivamente y mínimas de colesterol (6.50-4.42%. En los lípidos totales, los ácidos grasos saturados se encontraron entre 15.04 y 65.55%, con máximos en muestras de La Esmeralda y mínimos en Chacopata y los poliinsaturados estuvieron entre 7.80 y 37.18%, con máximos valores en la Brea y mínimos en la Esmeralda. En los fosfolípidos, la concentración de ácidos grasos saturados estuvo entre 38.81 y 48.68% para las muestras de Chaguaramas y Chacopata, respectivamente; los ácidos grasos poliinsaturados se encontraron entre no detectado y 34.51%, con altas concentraciones en muestras de Los Cedros (27.97% y Chaguaramas (34.51%. En los triacilgliceroles, la composición de ácidos grasos saturados variaron entre 14.27 y 53.80%, con baja concentración en Chacopata y alta concentración en La Restinga; los ácidos grasos poliinsaturados estuvieron entre 4.66 y 35.55%, con valores menores en las muestras de Chacopata (4.66% y mayores en Chaguaramas. El consumo frecuente de Perna viridis es recomendable, debido a su alto contenido de fosfolípidos y ácidos grasos insaturados.Lipid and fatty acid profile of Perna viridis, Green Mussel (Mollusca: Bivalvia in

  16. Miocene freshwater Mollusca from western Brazilian Amazonia

    NARCIS (Netherlands)

    Wesselingh, F.P.; Ranzi, A.; Räsänen, M.E.

    2006-01-01

    Thirteen species of fossil molluscs are reported from the Solimões Formation of western Brazilian Amazonia. Based on mammalian chronology of the Solimões Formation and radiometric ages reported from coeval deposits in adjacent Peru, the age of the fauna is established as Late Miocene. The fauna

  17. Lorentz Spengler's descriptions of chitons (Mollusca: Polyplacophora)

    NARCIS (Netherlands)

    Kaas, P.; Knudsen, J.

    1992-01-01

    The present paper deals with an important Danish paper on the Polyplacophora, published in 1797 by Lorentz Spengler: Udförlig Beskrivelse over det mangeskallede Konkylie-Slaegt, af Linnaeus kaldet Chiton; med endeel nye Arter og Varieteter. -Skrivter af Naturhistorie-Selskabet, 4e Bind, Ie Hefte,

  18. Short Communication Myosotella myosotis (Mollusca: Ellobiidae ...

    African Journals Online (AJOL)

    Myosotella myosotis is shown to be a well-established alien species in South Africa. Discovered in Port Elizabeth more than 100 years ago, it was initially thought to be indigenous and was described under two different names, but subsequent taxonomic work has demonstrated that these are synonyms of the variable and ...

  19. Radiochemical investigation of the bioaccumulation of urea by the alga Hydrodictyon reticulatum

    International Nuclear Information System (INIS)

    Havelka, M.; Stary, J.; Kratzer, K.

    1987-01-01

    It is found that the bioaccumulation of 14 C-urea in the light is connected with the increase of pH-value of the external medium, of the intracellular concentration of ammonium ions and with the decrease of the intracellular concentration of potassium ions. The uptake rate does not depend on the concentration of urea in the range from 0.1 to 2.0 mmol dm -3 and it has a broad maximum at pH 6.5-8.0. The uptake rate of urea is a little higher compared with nitrite or nitrate anions, however it is at least three times lower in comparison with that of ammonium or hydrocarbonate ions. The uptake of urea in the dark leads to the increase of the intracellular concentration of ammonium ions, however, carbon dioxide formed is released from the cell. (author) 7 refs

  20. Description of the manufacture of a Geiger-Muller counter with window; Descripcion de la fabricacion de un contador Geiger-Muller con ventana

    Energy Technology Data Exchange (ETDEWEB)

    Granados, C E

    1959-07-01

    Total details about the manufacture elements in counter fabrication and the way of obtention are described as well as total indications useful in the installation process and filling of the counter. The appropriate materials and precautions that might be adopted in order to obtain counters with uniform operation and good characteristics, are described. Counters are of brass, with thin mica or aluminium windows and operate at 1100 V approximately with a slope lower than 5 % 1100 V. (Author)

  1. Chitons (Mollusca, Polyplacophora) from Alacranes Reef, Yucatan, Mexico

    Science.gov (United States)

    Reyes-Gómez, Adriana; Ortigosa, Deneb; Simões, Nuno

    2017-01-01

    Abstract This study represents the first comprehensive chiton study from Alacranes Reef, the largest reef system in the Gulf of Mexico. Nine chiton species were found in seven localities within the area, in the intertidal and subtidal to 12 m depth. SEM examination of C. janeirensis, A. hemphilli, T. schrammi and C. floridanus, showed variations in the sculpture and radular teeth morphology when compared to specimens of the same species from Florida Keys, Bahamas and Puerto Rico. The distribution ranges of T. schrammi, L. liozonis and S. floridana are extended into the south-western area of the Gulf of Mexico. Altogether, combining previous literature and the present survey, reports eleven chiton species which have now been recorded within the Alacranes reef area. PMID:28769624

  2. Planaxidae (Mollusca, Gastropoda) from the South China Sea

    Science.gov (United States)

    Chen, Zhiyun; Zhang, Junlong; Lian, Xiping; Tan, Yehui

    2018-03-01

    Planaxidae is a family of tropical and subtropical marine gastropods that are adapted to an intertidal, rocky environment. The present study deals with three species in the family Planaxidae from the South China Sea: Planaxis sulcatus (von Born, 1778), Angiola longispira (Smith, 1872), and Supplanaxis niger (Quoy and Gaimard, 1833), based on specimens deposited in the Marine Biodiversity Collections of the South China Sea, Chinese Academy of Sciences. The taxonomic status, main morphological characteristics of the shell and radula, distribution, and habitat of these three planaxid species are presented. We also briefly discuss their morphological differences and the biogeographic distribution.

  3. Vanadium, rubidium and potassium in Octopus vulgaris (Mollusca: Cephalopoda

    Directory of Open Access Journals (Sweden)

    Sónia Seixas

    2005-06-01

    Full Text Available The levels of vanadium, rubidium and potassium were determined in Octopus vulgaris caught during commercial fishing activities at three locations (Cascais, Santa Luzia and Viana do Castelo in Portugal in autumn and spring. We determined the concentration of these elements in digestive gland, branchial heart, gills, mantle and arms in males and females. At least five males and five females were assessed for each season/location combination. Elemental concentrations were determined by Particle Induced X-ray Emission (PIXE. Vanadium was detectable only in digestive gland and branchial heart samples. Its concentration was not correlated with total weight, total length or mantle length. There were no differences in concentrations of V, Rb and K between sexes. There were significant differences in vanadium concentrations in branchial hearts in autumn between samples from Viana do Castelo and those from the other two sites. We found a significant positive relationship between the concentration of vanadium and those of potassium and rubidium in branchial hearts. Branchial hearts appear to play an important role in decontamination of V.

  4. Clio pyramidata Linnaeus, 1767 forma convexa (Boas, 1886) (Mollusca, Pteropoda)

    NARCIS (Netherlands)

    Spoel, van der S.

    1973-01-01

    The pelagic fauna of the Red Sea shows special variation induced by its isolated character (Van der Spoel, 1971). Clio pyramidata from the Red Sea is usually incorrectly referred to as the tropical forma lanceolata (Lesueur, 1813) or the typical forma pyramidata Linnaeus, 1767. Some large samples

  5. Parasitism by a Digenea in Lucina pectinata (Mollusca: Lucinidae

    Directory of Open Access Journals (Sweden)

    M. M. Ribeiro

    2017-06-01

    Full Text Available Abstract Lucina pectinata is an important economic resource in the Brazilian coast. This study reports parasitism caused by a Digenea in this species. The specimens (n = 470 were collected in December 2012 in a mangrove swamp of the Cachoeira River estuary, Bahia, Brazil. They were measured along the anterior-posterior axis (length, and after macroscopic analysis for parasites and diseases cuts of 5 mm were fixated in Carnoy’s solution and processed by routine histology technique wherein sessions of 7 μm were stained with Harris hematoxylin and eosin (H&E. The tissues were examined using an optical microscope. The mean length of L. pectinata was 4.0 ± 0.53 cm. Microscopic analysis showed sporocysts containing both germ balls as cercariae of an unidentified Digenea (Platyhelminthes, these in various stages of development. The prevalence was 1.48% (7/470. In a parasitized specimen was macroscopic evidence of tissue densification of gills. The sporocysts were observed in mantle, gills, digestive gland and gonads, with evident alteration/destruction of tissues, including parasitic castration. There were no other parasites found, which is probably related to inaccessibility and chemical conditions in which lives L. pectinata, i.e., between 10 and 20 cm in mangrove sediment.

  6. Octopus tetricus (Mollusca: Cephalopoda as an ecosystem engineer

    Directory of Open Access Journals (Sweden)

    David Scheel

    2014-12-01

    Full Text Available The Sydney octopus (Octopus tetricus occurs in unusual numbers on a shell bed of its prey remains that have accumulated as an extended midden where additional octopuses excavate dens. Here, O tetricus are ecosystem engineers, organisms that modulate availability of resources to other species and to their own species by causing physical state changes in materials. A community of invertebrate grazers and scavengers has developed on the shell bed. Fishes are attracted to the shell bed in numbers significantly greater than in nearby habitats. Large predators, including wobbegong sharks, were attracted to and fed on concentrations of fish, inhibiting the activities of the original engineers, the octopuses. Positive feedbacks included the accumulation of shell debris, increasing shelter availability for additional octopuses and aggregating fish. Negative feedbacks included reductions of nearby prey size and availability, aggression among octopuses, and predator limitation to octopus activity that would otherwise maintain the shell bed.

  7. On Pomacea canaliculata (Lamarck, 1822 (Mollusca; Pilidae: Ampullariidae

    Directory of Open Access Journals (Sweden)

    Silvana C. Thiengo

    1993-03-01

    Full Text Available This paper deals with the morphology of Pomacea caniculata (Lamarck, 1822 collected at Corrientes, Argentina. Comparison is made with Pomacea lineata (Spix, 1827 and Pomacea sordida (Swainson, 1823. The shell is globose, heavy, with greenish or horn-colored periostracum and dark spiral bands; apex subelevated, 5-6 whorls increasing rather rapidly and separated by very deep suture. Aperture large, rounded to subelongated; lip sometimes reddish; umbilicus large and deep; operculum corneous, entirely closing the aperture. Ratios: shell width/shell length = 0.78-0.96 (mean 0.86; aperture length/shell length = 0.68-0.77 (mean 0.72. Radula similar to other congeneric species. Testis and spermiduct as in P. lineata and P. sordida; prostate cylindric and short, cream in color as the testis. Penial sheath straight bearing a central outer gland deeply embedded in the tissue of its basal portion and a large wrinkled gland occupying 2/3 of the distal tip of its inner surface; the rigth margin of the sheath overlaps the left one until 2/3 of its proximal end. Female reproductive apparatus similar to that P. lineata; vestigial male copulatory apparatus (penis and its sheath present in all females examined.

  8. Gundlachia dutrae: n. sp. from northwest Brazil (Mollusca: Basommatophora: Ancylidae

    Directory of Open Access Journals (Sweden)

    Sonia Barbosa dos Santos

    1994-06-01

    Full Text Available A new species of Gundlachia, Gundlachia dutrae is described from northwest Brazil. It is distinguishable from other congenerie species by characteristics of the shell, radula and internal organs. Shell relatively high. Aperture near-circular; periostracum dark brown without periostracal hairs. Apex slightly inclined to the right, projected but not hooked, with an apical depression surrounted by a sculpture of well-marked irregular punctations. Shell surface with prominent radial sculpture. No septate specimens were observed. Ratios (n= 59: shell width/shell lenght = 0,66- 0,79 (mean 0,73; shell height/shell length = 0,32- 0,45 ( mean 0,37; shell height/shell width = 0,43- 0,63 (mean 0,51. Body of normal ancylid type; mantle pigmentation dark brown or black, concentrated along the mantle collar. The dorsal surface of the right anterior muscle is elongated and medially constricted. The left anterior and the posterior muscles are almost elliptical. Adhesive area is V-shaped. Pseudobranch unpigmented bearing a very small and thin dorsal lobe. Ovotestis with more than 25 unbranched diverticula. Ovispermiduct with seminal vesicle rather developed. Elongated nidamental gland continous with the glandular wall of the uterus. Nidamental gland appendix ending into a bulbous swelling Spermathecal body almost rounded. Well-developed prostate with five long diverticula. Ejaculatory complex with long glandular flagellum, without a penis or true ultra-penis. "Penis sheath" developed. "Ultra-penis" projected as a tube inside the lumem of prepuce, with a slit between "ultra-penis" and "penis sheath". Rachidian tooth tetracuspid, with two median cusps assymmetrical and aculeated. Lateral teeth tricuspid, with a reduced endocon and a prominent mesocon. A well marked gap occurs between meso and ectocon. Marginal teeth similar to lateral ones. Jaw T-shaped, with about 28 dorsal plates.

  9. Variation in foraging activity of Acanthochitona garnoti (Mollusca ...

    African Journals Online (AJOL)

    Foraging activity of Acanthochitona gamoti was studied during spring and neap tides in three different habitats: an aeolian sandstone ... mm) during a spring tide new moon and least on a spring tide full moon (x = 4.0 h; x = 182 rnm). Chitons on the boulder ..... BECKLEY, L.E. 1994. Two Oceans: A guide to Marine Life of.

  10. Imposex in endemic volutid from Northeast Brazil (Mollusca: Gastropoda

    Directory of Open Access Journals (Sweden)

    Ítalo Braga de Castro

    2008-10-01

    Full Text Available Imposex is characterized by the development of masculine sexual organs in neogastropod females. Almost 120 mollusk species are known to present imposex when exposed to organic tin compounds as tributyltin (TBT and triphenyltin (TPT. These compounds are used as biocide agents in antifouling paints to prevent the incrustations on boats. Five gastropod species are known to present imposex in Brazil: Stramonita haemastoma, Stramonita rustica, Leucozonia nassa, Cymathium parthenopeum and Olivancillaria vesica. This paper reports the first record of imposex observed in the endemic gastropod Voluta ebraea from Pacheco Beach, Northeast Brazil. Animals presenting imposex had regular female reproductive organs (capsule gland, oviduct and sperm-ingesting gland and an abnormal penis. As imposex occurs in mollusks exposed to organotin compounds typically found at harbors, marinas, shipyards and areas with high shipping activities, probably contamination of Pacheco Beach is a consequence of a shipyard activity located in the nearest areas.O imposex caracteriza-se pelo surgimento de estruturas sexuais masculinas, em fêmeas de gastrópodes. Cerca de 120 espécies de moluscos que exibem o fenômeno quando expostas a contaminação por compostos orgânicos de estanho tais como o Tributilestanho (TBT e o Trifenilestanho (TPT. Esses compostos são utilizados, sobretudo em embarcações, no intuito de evitar a bioincrustração que danifica as embarcações e eleva os custos das viagens marítimas. No Brasil se conhecem 5 espécies de moluscos gastrópodes que manifestam imposex, são elas: Stramonita haemastoma, Stramonita rustica, Leucozonia nassa, Cymathium parthenopeum e Olivancillaria vesica. No Nordeste, monitoramentos da contaminação por organoestânicos foram realizados utilizando o imposex em gastrópodes como biomarcador. O presente estudo tem por objetivo notificar a primeira ocorrência de imposex na espécie endêmica do Nordeste brasileiro, Voluta ebraea. De um total de 11 animais observados, duas fêmeas apresentaram imposex, provenientes da Praia do Pacheco no litoral do Ceará. Observou-se nesses indivíduos a presença de glândula de cápsulas, ovidutos e receptáculo seminal concomitantemente ao pênis o que caracteriza o imposex. Como o imposex só se manifesta em moluscos expostos a compostos organoestânicos tipicamente encontrados em portos, marinas, estaleiros e locais com grande fluxo de embarcações atribui-se a origem dessa contaminação provavelmente a um estaleiro localizado nas proximidades da área de coleta.

  11. The non-marine Mollusca of St. Martin (Lesser Antilles)

    NARCIS (Netherlands)

    Coomans, H.E.

    1967-01-01

    After our studies about the marine mollusks of St. Martin, (COOMANS 1963a, 1963b), this publication will deal with the land and freshwater shells of the island. The non-marine mollusks of St. Martin were already fairly well known at the end of the last century (MAZÉ 1890, p. 22—34), who mentioned 36

  12. Chitons (Mollusca, Polyplacophora from Alacranes Reef, Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Adriana Reyes-Gómez

    2017-04-01

    Full Text Available This study represents the first comprehensive chiton study from Alacranes Reef, the largest reef system in the Gulf of Mexico. Nine chiton species were found in seven localities within the area, in the intertidal and subtidal to 12 m depth. SEM examination of C. janeirensis, A. hemphilli, T. schrammi and C. floridanus, showed variations in the sculpture and radular teeth morphology when compared to specimens of the same species from Florida Keys, Bahamas and Puerto Rico. The distribution ranges of T. schrammi, L. liozonis and S. floridana are extended into the south-western area of the Gulf of Mexico. Altogether, combining previous literature and the present survey, reports eleven chiton species which have now been recorded within the Alacranes reef area.

  13. The Genus Theba (Mollusca: Gastropoda: Helicidae), Systematics and Distribution

    NARCIS (Netherlands)

    Gittenberger, E.; Ripken, Th. E.J.

    1987-01-01

    Our knowledge concerning taxonomy and zoogeography of the fossil and recent species of the helicid genus Theba is summarized and enlarged. The fossil T. arinagae spec. nov. is described from Gran Canaria. The recent T. andalusica spec. nov. and T. sacchii spec. nov. are described from the

  14. Nematodes from Achatina fulica Bowdich, 1822 (Mollusca: Gastropoda in Argentina

    Directory of Open Access Journals (Sweden)

    Valente R.

    2016-03-01

    Full Text Available The aim of this study is to describe the nematode cysts and larvae found in Achatina fulica, the giant African snail, in the northeast of Argentina. A total of 373 snails were collected from the cities of Puerto Iguazú and Corrientes. Cysts (N= 2958 containing nematodes identified as L3 Strongyluris sp. were found in the mantle cavity of 87 snails from Puerto Iguazú City (Prevalence 23 %; Mean Intensity= 34; Mean Abundance= 8. The shell size correlated with prevalence, mean intensity and mean abundance (p < 0.05 indicating that there is an exposure-infection constant rather than an accidental one. In other hand, the absence of infection in the smallest shell size suggests a threshold of size to be infected. Taking into account that there exist records of A. fulica infected by nematodes of medical and veterinary importance such as Angiostrongylus and Aelurostrongylus in some Brazilian states near Puerto Iguazú, we emphasize the need for snail surveillance.

  15. A new species of Indo-Pacific Modulidae (Mollusca: Caenogastropoda).

    Science.gov (United States)

    Lozouet, Pierre; Krygelmans, Anouchka

    2016-04-12

    Modulidae is a littoral cerithioid family exclusively encountered in tropical and subtropical regions. It contains 12 to 15 living species (some species are not clearly delimited). Only one species is known to occur in the vast Indo-Pacific region (Bouchet 2015) and two species in the eastern Atlantic. By comparison, the tropical American regions are relatively rich with at least eleven living species (two or three species in the eastern Pacific and nine or more in the western Atlantic), and an equivalent number or more of fossil species (Landau et al. 2014).

  16. Diversity of Indo-West Pacific Siphonaria (Mollusca: Gastropoda: Euthyneura).

    Science.gov (United States)

    Dayrat, Benoît; Goulding, Tricia C; White, Tracy R

    2014-03-14

    Species of the limpet genus Siphonaria (Gastropoda: Euthyneura) are commonly found in the rocky intertidal, worldwide, except in the Arctic. In total, 205 species-group names are available and not permanently invalid. However, estimating the actual species diversity of Siphonaria has remained challenging, mainly because past authors have interpreted differently the variation of shell characters, resulting in different taxonomic accounts. Species diversity of Siphonaria is evaluated for the first time here based on DNA sequence data (three mitochondrial gene fragments: COI, 12S, and 16S) and a large sampling focusing on the tropical and subtropical Indo-West Pacific (from eastern Africa to Hawaii): new sequences are provided for 153 individuals, 123 of which were collected from 93 locations throughout the Indo-West Pacific. In total, 41 species (molecular units) are recognized worldwide (31 from the Indo-West Pacific), all of which are strongly supported. Potential names are discussed for those 41 species, based on traditional taxonomy. The shells of 66 of the individuals from which DNA was extracted are illustrated: intra- and inter-specific variation is documented in detail and discussed in the light of new molecular results. It is shown that many species could hardly be identified based on the shell only, because the variation of shell characters is too high and overlaps between species. Geographically, no species is found across the entire Indo-West Pacific, where quite a few species seem to be endemic to restricted areas. The biogeography of Siphonaria in the Indo-West Pacific is compared to other groups.

  17. Intramantle Inking: A Stress Behavior in Octopus bimaculoides (Mollusca: Cephalopoda)

    Science.gov (United States)

    Toll, Ronald B

    2011-01-01

    Several Pacific 2-spot octopuses (Octopus bimaculoides) shipped from California and held in a recirculating seawater system at Illinois College exhibited an unusual postshipping stress behavior not previously documented in the literature. Ink, normally ejected into the surrounding seawater, was uncharacteristically retained in the mantle cavity. We describe the resulting behaviors, discuss successful resuscitation efforts, and briefly consider the possible role(s) that ink may have played in the death of one octopus. PMID:22330791

  18. On locality of Generalized Reed-Muller codes over the broadcast erasure channel

    KAUST Repository

    Alloum, Amira; Lin, Sian Jheng; Al-Naffouri, Tareq Y.

    2016-01-01

    , and more specifically at the application layer where Rateless, LDPC, Reed Slomon codes and network coding schemes have been extensively studied, optimized and standardized in the past. Beyond reusing, extending or adapting existing application layer packet

  19. Applications Geiger-Muller detectors monitor the level of radioactivity in the human body

    International Nuclear Information System (INIS)

    Gunarwan Prayitno

    2008-01-01

    Nuclear technology is the technology high risk, because of an application and implementation have to support by human skill. The support facility has to complete and up to date, or modern. It means if the accident occurs in mistake have to do or delayed something, they can solved that problem. So the probability the risk of accident can be minimized. The specific problem is in the implementation nuclear technology on the human safety which is works in the radiation field or in the environment where they are working. The pointer that the problems have to design the tools monitor to monitoring the value radiation maximum was allowed. The tools monitor design is giving the information signal, if the radiation level maximum have over limit. Whereas the high and low level radiation can be just depend on the needed. (author)

  20. A freak twin trilobite larva of the Indian horseshoe crab Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Mishra, J.K.; Chatterji, A.; Parulekar, A.H.

    Early embryonic stages of a horseshoe crab Tachypleus gigas were studied using micrographs of live embryo. A freak egg showing two trilobite larvae bridged with each other was noticed on 38th day after fertilization. Morphology of this egg has been...

  1. Regeneration of gill lamellae of the Indian horseshoe crab, Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Alam, H.; Joshi, B.K.; Bhonde, R.R.

    taxa of other plant groups l ike Coniferales and Cycadales. The appea r- ance of Ginkgoales in India du r ing Early Cretaceous is significant. Ther e fore, the present study is aimed to trace its lineage from the earl i est record of fossils from...

  2. Nesting behaviour of the Indian horseshoe crab, Tachypleus gigas (Muller) (Xiphosura)

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Parulekar, A.H.; Qasim, S.Z.

    stream_size 14 stream_content_type text/plain stream_name Indias_EEZ_1996_142.pdf.txt stream_source_info Indias_EEZ_1996_142.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  3. Effect of temperature on 'N' uptake of Chaetomorpha linum (Muller) and Padina tetrastomatica (Hauck)

    Digital Repository Service at National Institute of Oceanography (India)

    Raikar, V.; Wafar, M.V.M.

    of temperature were tested at 4 different temperatures (20, 25, 30 and 35 degrees C). The irradiance measured during the incubation period was 276 mu E m sup(-2) s sup(-1). The duration of each experiment was 1 h. The experiments were carried out in duplicates...

  4. Description of the manufacture of a Geiger-Muller counter with window

    International Nuclear Information System (INIS)

    Granados, C. E.

    1959-01-01

    Total details about the manufacture elements in counter fabrication and the way of obtention are described as well as total indications useful in the installation process and filling of the counter. The appropriate materials and precautions that might be adopted in order to obtain counters with uniform operation and good characteristics, are described. Counters are of brass, with thin mica or aluminium windows and operate at 1100 V approximately with a slope lower than 5 % 1100 V. (Author)

  5. Long-term in vitro generation of amoebocytes from the Indian horseshoe crab Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Joshi, B.; Chatterji, A.; Bhonde, R.

    Amoebocyte is the single type of cell circulating in the horseshoe crab hemolymph, which plays a major role in the defense system of the animal. Granules present in these cells are sensitive to nanogram quantities of bacterial endotoxins, which form...

  6. Sets of disjoint snakes based on a Reed-Muller code and covering the hypercube

    NARCIS (Netherlands)

    Van Zanten, A.J.; Haryanto, L.

    2008-01-01

    A snake-in-the-box code (or snake) of word length n is a simple circuit in an n-dimensional cube Q n , with the additional property that any two non-neighboring words in the circuit differ in at least two positions. To construct such snakes a straightforward, non-recursive method is developed based

  7. Muller cell-specific autoantibodies in a patient with progressive loss of vision

    NARCIS (Netherlands)

    Peek, R.; Verbraak, F.; Coevoet, H. M.; Kijlstra, A.

    1998-01-01

    PURPOSE. To study the specificity of circulating retinal autoantibodies in a patient with progressive loss of vision resembling cancer-associated retinopathy in the absence of systemic malignancy. METHODS. Patient's serum was tested for the presence of antiretinal antibodies by Western blot

  8. Spawning migration of the horseshoe crab, Tachypleus gigas (Muller), in relation to lunal cycle

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Rathod, V.; Parulekar, A.H.

    Effects of lunar phases and tidal height on the spawning migration of the horseshoe crab, Tachypleus gigas, along the northeastern coast of India were studied. Mature pairs of crabs migrate towards the shore and build their nests in sandy beaches...

  9. Canonical multi-valued input Reed-Muller trees and forms

    Science.gov (United States)

    Perkowski, M. A.; Johnson, P. D.

    1991-01-01

    There is recently an increased interest in logic synthesis using EXOR gates. The paper introduces the fundamental concept of Orthogonal Expansion, which generalizes the ring form of the Shannon expansion to the logic with multiple-valued (mv) inputs. Based on this concept we are able to define a family of canonical tree circuits. Such circuits can be considered for binary and multiple-valued input cases. They can be multi-level (trees and DAG's) or flattened to two-level AND-EXOR circuits. Input decoders similar to those used in Sum of Products (SOP) PLA's are used in realizations of multiple-valued input functions. In the case of the binary logic the family of flattened AND-EXOR circuits includes several forms discussed by Davio and Green. For the case of the logic with multiple-valued inputs, the family of the flattened mv AND-EXOR circuits includes three expansions known from literature and two new expansions.

  10. Feeding behaviour and food selection in the horseshoe crab, Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A; Mishra, J.K.; Parulekar, A

    The Indian horseshoe crab, Tachypleus gigas, is a benthic feeder which subsists mainly on molluscs, decayed organic matter and polychaetes, in order of prevalence. A strong and positive preference was recorded for molluscs over other food organisms...

  11. Effect of salinity on larval growth of horseshoe crab, Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Kotnala, S.; Mathew, R.

    abou t 200 eggs per spawning on the sandy beaches and the male fe r tilizes them. The trilobite larvae hatch out 40 ? 45 days after fertilization and return to the sea. Du r- ing different developmental stages and migration, the tr i- lobite is su b...N; long 84 ?53 minuteE). The ga m- etes were collect ed and fertilized in vitro following the method described by Chatterji 1 . Fertilized eggs were i n cu - bated at 27 ? 1 ?C with adequate aeration. Hatching of the larvae occurred 42 ? 45 days...

  12. Energy source in the developing eggs of the Indian horseshoe crab, Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Aguiar, Q.; Saldanha, C.

    Wet weight, dry weight, water content, ash weight, soluble and insoluble proteins, carbohydrates, lipids, and glycogen were determined from 0 to 40th day after fertilization of the developing eggs of the Indian horseshoe crab, Tachypleus gigas...

  13. Barbarid, plastiliinijänes, Miriam ja Frank Muller / Annika Koppel

    Index Scriptorium Estoniae

    Koppel, Annika

    2003-01-01

    Nukufilm näitab 4 uut filmi : "Barbarid" (stsenaristid Andrus Kivirähk ja Hardi Volmer, režissöör H. Volmer), "Porgand" (stsenarist Peep Pedmanson, režissöör Pärtel Tall), "Miriami jõulupäkapikk" (stsenaristid Leelo Tungal ja Peep Pedmanson, režissöör Mait Laas), "Kuuvaatleja" (reklaamitreiler Frank Mulleri kellafirmale ; stsenarist, režissöör, kunstnik Mati Kütt)

  14. Does apparent size capture attention in visual search? Evidence from the Muller-Lyer illusion.

    Science.gov (United States)

    Proulx, Michael J; Green, Monique

    2011-11-23

    Is perceived size a crucial factor for the bottom-up guidance of attention? Here, a visual search experiment was used to examine whether an irrelevantly longer object can capture attention when participants were to detect a vertical target item. The longer object was created by an apparent size manipulation, the Müller-Lyer illusion; however, all objects contained the same number of pixels. The vertical target was detected more efficiently when it was also perceived as the longer item that was defined by apparent size. Further analysis revealed that the longer Müller-Lyer object received a greater degree of attentional priority than published results for other features such as retinal size, luminance contrast, and the abrupt onset of a new object. The present experiment has demonstrated for the first time that apparent size can capture attention and, thus, provide bottom-up guidance on the basis of perceived salience.

  15. Producción de YTX por cultivos de Protoceratium reticulatum: variabilidad en el perfil de toxinas de diferentes cepas

    OpenAIRE

    Paz, Beatriz

    2008-01-01

    Proyectos "Producción de toxinas marinas a partir de cultivos de dinoflagelados" CICYT, REN2001-2959-C04-01. "Producción de toxinas marinas a partir de cultivos de dinoflagelados" CICYT AGL2004-08241-C04-02/ALI". "Producción de toxinas liposolubles" (Ostreoscinas y Yessotoxinas). Subproyecto 1: "Producción de toxinas marinas por cultivos de dinoflagelados" del proyecto coordinado "Análisis de toxinas en alimentos de origen marino: Identificación de cultivos de los microorganismos res...

  16. Biomedical and pharmacological potential of tetrodotoxin-producing bacteria isolated from marine pufferfish Arothron hispidus (Muller, 1841

    Directory of Open Access Journals (Sweden)

    S Bragadeeswaran

    2010-01-01

    Full Text Available Specimens of the pufferfish Arothron hispidus collected at Parangipettai, on the southeast coast of India, were subjected to bacterial isolation and identification. Three species were identified, namely Bacillus sp., Kytococcus sedentarius and Cellulomonas fimi. Partially-purified microbial filtrates exhibited hemolytic activity on chicken and human erythrocytes of O, B and AB blood groups, with maximum activity of 32 HU. The microbial filtrates also presented ATPase, Mg2+-ATPase, Na+K+-ATPase and AchE enzymatic activities of positive neuromodulation in Kytococcus sedentarius with 1300, 300.1, 1549.98 and 140.55%, in Cellulomonas fimi with 620, 300, 10 and 128.42%, and in Bacillus species with 40, 200, 849.98 and 158.69%, respectively. Toxicity symptoms were observed when the bacterial filtrate was intraperitoneally injected into mice. The bacterial filtrate caused adverse effects on viability of the mouse muscle cell line (L929 and leukemia cell line (P388. Maximum level of inhibition was observed on the growth of L929 cell line. Bacillus lentimorbus inhibited the cell line from 84.03 to 94.43% whereas Bacillus species inhibited the growth in a range between 77.25 and 86.16% at the lowest dilution.

  17. Episodic human activities and seasonal impacts on the Tachypleus gigas (Muller, 1785) population at Tanjung Selangor in Peninsular Malaysia

    Digital Repository Service at National Institute of Oceanography (India)

    Nelson, B.R.; Satyanarayan, B.; Zhong, J.M.H.; Shaharome, F.; Sukumaran, M.; Chatterji, A.

    absence during 2011 (PRIMER v.6) Since Tanjung Selangor beach (adjoining the Terus and Pahang Tua estuary) is one of the very few known spawning grounds for the Malaysian horseshoe crab (T gigas), it is imperative to conserve and manage this area...

  18. Seasonal variations in the volume of the haemolymph and body weight of the horseshoe crab, Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Rathod, V.; Parulekar, A.H.

    in sizes between 121-140 mm. An inverse relationship was observed between the volume of haemolymph and salinity of the environment. Maximum volume of haemolymph (57.3 ml) in females was observed when the salinity of the environment was low in October...

  19. Effect of juvenile hormone and serotonin (5-HT) on mixis induction of the rotifer Brachionus plicatilis Muller.

    Science.gov (United States)

    Gallardo; Hagiwara; Snell

    2000-09-05

    Juvenile hormone (JH) and serotonin (5-HT) were previously shown to enhance mictic (sexual) female production of the rotifer Brachionus plicatilis in batch cultures. To explore the basis of these effects, experiments were conducted on isolated individuals. JH treatment of maternal rotifers with 5 and 50 µgml(-1) (18.8 and 187.7 µM) resulted in significantly higher (P<0.05) mictic female production in the second (F(2)) and third (F(3)) generations. JH treatment was effective even at a lower food concentration of 7x10(5) cellsml(-1), but it was not effective when free ammonia was added at 2.4 and 3.1 µgml(-1). Mictic female production was not increased with exposure to 5-HT up to 50 µgml(-1) (129.1 µM) concentrations. When food level was reduced to 7x10(5) cellsml(-1), however, 5-HT-treated rotifers produced significantly (P<0.05) more mictic females than the control, particularly in F(3) generation. Mictic female production of 5-HT-treated rotifers did not differ from that of the control with or without free ammonia, but the intrinsic rate of natural increase (r) of 5-HT-treated rotifers at 3.1 µgml(-1) free ammonia was significantly higher than the control. These results show that juvenile hormone increases mictic female production under optimum and sub-optimum food levels, whereas 5-HT increases both mictic female production at low food level and population growth rate at high free ammonia concentrations. These compounds could be used to manage rotifer cultures and probe the mechanisms controlling the rotifer life cycle as it switches to mictic reproduction.

  20. Cesium-134 assimilation and retention in the landsnail Helix aspersa Muller 1974. Its potential usefulness as bioindicator for radioactive contamination

    International Nuclear Information System (INIS)

    Alfonso, L.A.; Carvalho, F.P.

    1986-01-01

    Cesium-134 retention was experimentally studied on two groups (n=20 in each) of the land-snail Helix aspersa, labelled either through ingestion of labelled food or the radionuclide injection into the foot muscle. Cesium elimination was found to be not dependent from the labelling technique used. The mean biological half-life for Cs retention in both Helix groups was 53.6+- 0.8 d for the largest retention component, accounting for 0.88 of the initally absorbed Cs. Another experiment runned on a similar size Helix group allowed the gravimetric determination of food ingestion rate (8.8 mg/ g/day) and food assimilation efficiency (0.70+-0.20). Predictive modelling of Cs accumulation by Helix indicates a relatively high bioaccumulation potential in this species. This fact, together with the long biological half-life found for Cs retention, indicate that land snails could be used as suitable bioindicators for radioactive pollution in restrict terrestrial areas. (author)

  1. Beta, gamma contamination analysis of thermo luminescence dosimeter cassettes using Geiger Muller counting set up and gamma spectrometry techniques

    International Nuclear Information System (INIS)

    Prasad, S.K.; Sudheer, T.S.; Sahoo, L.; Vinayagam, Bhakti; Kamble, Mahesh; Khuspe, R.R.; Anilkumar, Rekha; Verma, K.K.

    2009-01-01

    Β-γ contamination cheek up of TLD cassettes were carried out and the isotopes found were 137 Cs, 106 Ru, 60 Co, 64 Cu, 144 Ce and 95 Nb with activity per square cm varying from 0.05-4.70 Bq/cm 2 with median value 1.3. The assessed dose in TLD was in the range of 2.10 mSv to 22.05 mSv for beta, 0.05 mSv to 5.25 mSv for gamma. The beta doses have median value of 6.19 mSv. This contamination may be due to active water contamination on TLD's of personnel working for irradiated fuel handling or work in fuel rod (under water) storage area. This gives a method to estimate skin exposure of personnel due to skin contamination during work. Chances of getting TLD's contaminated due to various reasons were studied. Contamination was found maximum inside the cassette box having area 16 cm 2 . In case of plastic pouch of TLD disc contamination was detected in three cases. Contamination level on TLD cassettes using GM counter was found in the range of 0.30-3.6 Bq/cm 2 for cassettes. By opening the window of the surveymeter contamination and field of these cassettes in closed condition were found to increase by 20% due to the measurement of beta dose. With the same condition contamination of TLD cassette in open condition was found five times more. This is due to the a-contamination which is five times more than a contamination, The most prominent isotope 137 Cs in common chemical forms are soluble in water and if inhaled or ingested are rapidly and completely absorbed in the lungs and across the gastrointestinal tract. Thus a skin contamination of most prominent isotope 137 Cs can lead to intake in addition to skin dose. Fading studies of contamination of TLD cassettes were carried out. It was found negligible after counting with GM counting set up after a period of 3 months. But one of the TLD cassettes was showing an 80% reduction of contamination after 3 months with GM counting set up, the contaminants being 141 Ce, 103 Ru and 95 Nb. The gamma peaks in the external exposure are due to external exposure in specific work during the period. 60 Co is an activation product by activation of pipe line corrosion parts, while 64 Cu, a positron emitter is an activation product formed from 63 Cu from the tubing used in primary coolant water system. Beta contamination dose conversion factor of 2 mSv/Bq/cm 2 is arrived at, for a period of 1 month. (author)

  2. Muller glia, vision-guided ocular growth, retinal stem cells, and a little serendipity: the Cogan lecture.

    Science.gov (United States)

    Fischer, Andy J

    2011-09-29

    Hypothesis-driven science is expected to result in a continuum of studies and findings along a discrete path. By comparison, serendipity can lead to new directions that branch into different paths. Herein, I describe a diverse series of findings that were motivated by hypotheses, but driven by serendipity. I summarize how investigations into vision-guided ocular growth in the chick eye led to the identification of glucagonergic amacrine cells as key regulators of ocular elongation. Studies designed to assess the impact of the ablation of different types of neurons on vision-guided ocular growth led to the finding of numerous proliferating cells within damaged retinas. These proliferating cells were Müller glia-derived retinal progenitors with a capacity to produce new neurons. Studies designed to investigate Müller glia-derived progenitors led to the identification of a domain of neural stem cells that form a circumferential marginal zone (CMZ) that lines the periphery of the retina. Accelerated ocular growth, caused by visual deprivation, stimulated the proliferation of CMZ progenitors. We formulated a hypothesis that growth-regulating glucagonergic cells may regulate both overall eye size (scleral growth) and the growth of the retina (proliferation of CMZ cells). Subsequent studies identified unusual types of glucagonergic neurons with terminals that ramify within the CMZ; these cells use visual cues to control equatorial ocular growth and the proliferation of CMZ cells. Finally, while studying the signaling pathways that stimulate CMZ and Müller glia-derived progenitors, serendipity led to the discovery of a novel type of glial cell that is scattered across the inner retinal layers.

  3. Review of Studies on Visual Perception in Grey Parrots (Psittacus erithacus: The Muller-Lyer Illusion, Amodal and Modal Completion

    Directory of Open Access Journals (Sweden)

    Irene M. Pepperberg

    2017-08-01

    Full Text Available Few avian studies on optical illusions are directly comparable to those with humans. Grey parrots that have some referential use of English speech, however, allow for such comparative studies, as these birds can be tested just as are humans, by asking them to describe exactly what they have seen. Here I review two studies, one on the Müller-Lyer illusion (Pepperberg, Vicinay, & Cavanagh, 2008, one on amodal and modal perception (Pepperberg & Nakayama, 2016, that demonstrate similarities between human and Grey parrot perceptual abilities.

  4. Book Review: Potassic igneous rocks and associated gold-copper mineralization, Fourth edition (D. Muller and D.I. Groves)

    Science.gov (United States)

    Kelley, Karen D.

    2016-01-01

    The fourth edition of this comprehensive textbook, which succeeds those published in 1995, 1997, and 2000, very nicely summarizes the geochemical and petrological characteristics of potassic igneous rock complexes and the different tectonic settings in which they occur. The authors provide an overview and a classification of these rocks and they outline the geochemical differences between barren and mineralized potassic igneous complexes. Owing to the common association of potassic igneous rocks with many gold- and copper-rich ore deposits, this book will be of interest not only to research scientists but also to those exploring for major deposits in young and ancient terranes. In fact, there was a clear attempt by the authors to provide a good mix of theoretical discussions based on experimental work, with case studies that illustrate field and applied research.

  5. Genome-wide mapping in a house mouse hybrid zone reveals hybrid sterility loci and Dobzhansky-Muller interactions.

    Science.gov (United States)

    Turner, Leslie M; Harr, Bettina

    2014-12-09

    Mapping hybrid defects in contact zones between incipient species can identify genomic regions contributing to reproductive isolation and reveal genetic mechanisms of speciation. The house mouse features a rare combination of sophisticated genetic tools and natural hybrid zones between subspecies. Male hybrids often show reduced fertility, a common reproductive barrier between incipient species. Laboratory crosses have identified sterility loci, but each encompasses hundreds of genes. We map genetic determinants of testis weight and testis gene expression using offspring of mice captured in a hybrid zone between M. musculus musculus and M. m. domesticus. Many generations of admixture enables high-resolution mapping of loci contributing to these sterility-related phenotypes. We identify complex interactions among sterility loci, suggesting multiple, non-independent genetic incompatibilities contribute to barriers to gene flow in the hybrid zone.

  6. Observations on the morphology of Pomacea lineata (Spix, 1827 (Mollusca, Ampullariidae Observações sobre a morfologia de Pomacea lineata (Spix, 1827 (Mollusca, Ampullaridae

    Directory of Open Access Journals (Sweden)

    Silvana Carvalho Thiengo

    1987-12-01

    Full Text Available This paper deals with the morpholgy of Pomacea lineata (Spix, 1827 collected at its type locality. The shell is globose, moderately heavy, horn-colored with brown spiral bands; apex subelevated; 4 - 5 rounded whorls increasing in diameter rather rapidly, separated by deep suture. Aperture large and ovoid; outer lip sharp; umbilicus narrow and deep; operculum concentric, corneous. Ratios: shell width/shell length = 0.74 - 0.83 (mean 0.78; spire length/shell length = 0.10 - 0.18 (mean 0.13; aperture length/shell length = 0.70 - 0.77 (mean 0.73. The animal is longisiphonate. Renal organ brownish with marked invagination at its right edge. Ureter elongated with its long axis transverse to the main axis of the kidney. The radula is taenioglossate (2.1.1.1.2 and has on average 35 transverse rows of teeth. The form and arrangement of the radula teeth are nearly the same as in other Ampullariidae. The testis is cream-colored and lies in the first three whorls of the spire. Spermiduct uniformly narrow, running to the base of the spire. Seminal vesicle whitish, slightly pressed dorsoventrally. Prostate cylindric and thick, similar in color to the testis. Penis whiplike, with a closed circular spermiduct. Penis pouch ovoid completely envelping the penis. Penis sheath elongated, broad prosimally, tapering distally. Its inner surface shows a longitudinal channel along its proximal half and two glands, one on the middle and the other apical. Ovary composed of branched whitish tubules situated on the surface of the digestive gland. Oviduct slender running along the columellar axis toward the base of the spire. Seminal receptalble tubiform, thick-walled and rounded proximally. Albumen gland large, pink, enclosing the receptacle and the spiral capsule gland. Vestigial male copulatory apparatus (penis and its sheath present in all females examined.Neste trabalho e estudada a morfologia de Pomacea lineata (Spix, 1827 baseada em material coletado na localidade-tipo. Concha com espessura moderada, globosa, castanha, com faixas espirais castanhas-escuras; ápice pouco elevado, 4-5 giros arredondados crescendo rapidamente em diâmetro, separados por suturas profundas. Abertura grande oval; lábio externo simples; umbigo pequeno e profundo; opérculo concêntrico, córneo. Razão: largura da concha/comprimento da concha = 0.74 - 0.83 (média 0.78; comprimento da espira/comprimento da concha = 0.10 - 0.18 (média 0.13; comprimento da abertura/comprimento da concha = 0.70 - 0.77 (média 0.73. Animal com sifão bem desenvolvido. A rádula é tenioglossa (2.1.1.1.2 e tem em média 35 fileiras transversais de dentes. A forma e a disposição dos dentes radulares são semelhantes ao padrão dos ampularídeos. Rim de cor castanha apresentando uma invaginação acentuada na parede direita. Ureter alongado e transversal ao eixo principal do rim. Testículo constituído por uma massa cor creme, ocupando as três primeiras voltas da espira. Espermiduto estreito e uniforme, correndo para a base da espira. Vesícula seminal esbranquiçada levemente achatada dorso-ventralmente. Próstata cilíndrica e compacta com coloração semelhante à do testículo. Pênis em forma de chicote com canal espermático fechado e de contorno circular. Bolsa do pênis ovalada, envolvendo-o completamente. Bainha do pênis alongada tendo sua largura diminuída gradualmente da base para a extremidade; sua superfície interna apresenta um canal mediano em sua metade proximal e duas glândulas, uma mediana e outra apical. Ovário constituído por túbulos ramificados branco-amarelados situados superficilamente sobre a glândula digestiva. Oviduto estreito correndo pelo eixo columelar até a base da espira. Receptáculo seminal tubular com parede espessa e extremidade proximal alargada. Glândula de albume volumosa e rosada envolvendo o receptáculo seminal e a glândula da casca em espiral. Vestígio do aparelho copulador masculino (pênis e sua bainha presente em todas as fêmeas examinadas.

  7. Distribucion arborea de los gastropodos cerithidea montagnei (mollusca potamidae y littorina Spp. (Mollusca, Littorinidae en el manglar de Mata de Limón, Costa Rica

    Directory of Open Access Journals (Sweden)

    Édgar Suarez B

    2016-03-01

    Full Text Available En el manglar de Mata de Limón, Puntarenas, Costa Rica, se estudió la distribución y preferencia por el susbtrato arbóreo de gastrópodos C. montagnei y Littorina spp. en cuatro especies de mangle, según la cantidad de moluscos observados en cada árbol y la cantidad de árboles con presencia o ausencia de ellos, en el período de setiembre de 1982 a junio de 1983. El orden de preferencia mostrado por ambos grupos de moluscos fue: 1 Rhizophora mangle, 2 Avicennia germinans, 3Pelliciera rhizophorae y 4 Laguncularia racemosa. Se discuten las posibles razones de esta preferencia. Cerithidea montagnei presentó una mayor distribución horizontal, así como una mayor abundancia respecto de Littorina spp.

  8. Ocorrência do bivalve exótico Mytilopsis leucophaeta (Conrad (Mollusca, Bivalvia, no Brasil Occurrence of exotic bivalve Mytilopsis leucophaeta (Conrad (Mollusca, Bivalvia, in Brazil

    Directory of Open Access Journals (Sweden)

    José R. B. de Souza

    2005-12-01

    Full Text Available O molusco Mytilopsis leucophaeta (Conrad, 1831, natural da América do Norte, foi localizado no litoral de Pernambuco, Brasil, em 2004, trazido provavelmente por água de lastro de navios. Na região, sua distribuição atualmente abrange zonas estuarinas adjacentes ao Porto do Recife. Os organismos foram encontrados restritos à região entre-marés, formando agregados densos com até 176.800 ind./m².The mussel Mytilopsis leucophaeta (Conrad, 1831 is native to North America. It was found at Pernambuco Coast, northeastern Brazil, in 2004, probably brought by ships' ballast water. The distribution of this species has been now spread to estuarial area near Recife Harbour. They showed a clumped distribution with a maximum of 176,800 ind./m² only in the intertidal zone.

  9. Comportamento agregativo em Subulina octona (Brugüière (Mollusca, Subulinidae Aggregative behavior in Subulina octona (Brugüière (Mollusca, Subulinidae

    Directory of Open Access Journals (Sweden)

    Sthefane D'ávila

    2006-06-01

    Full Text Available O objetivo deste trabalho foi verificar a existência de comportamento agregativo na espécie Subulina octona (Brugüière, 1789 e obter evidências da mediação química desse comportamento. Foram utilizados 150 animais adultos, distribuídos em 15 caixas com terra vegetal (10 animais por caixa. Em cada caixa foram colocados quatro discos plásticos identificados, em posição eqüidistante, os quais serviram como abrigos para os animais. No experimento I, foram colocados 10 animais no centro de cada caixa. Após 24, 48, 96, 120, 144 e 168 horas foram observados o número de agregados formados, a posição dos agregados (sob qual abrigo, o número de indivíduos por agregado e o número de indivíduos isolados. No experimento II, todos os indivíduos foram transferidos para outras caixas contendo terra vegetal, três novos discos e o disco que continha o maior agregado após as 168 horas do experimento I (denominado disco condicionado. Foi verificado, após 24 e 48 horas, o número de indivíduos sob o disco condicionado. Em todas as caixas utilizadas e em todos os intervalos de tempo observados no experimento I, houve a formação de agregados. Houve um aumento significativo do número de indivíduos por agregado e uma diminuição do número de indivíduos isolados com o passar do tempo (ANOVA, p The current study aimed to verify the existence of aggregative behavior in Subulina octona (Brugüière, 1789 and to obtain behavioral evidence of chemical mediation of this behavior. We used 150 adult animals allocated in 15 boxes with humus (10 animals per box. In each box we placed four identified plastic disks in an equidistant position. These disks worked as shelters for the animals. In experiment I, 10 animals were put in the middle of each box. After 24, 48, 96, 120, 144, and 168 hours we observed the number of formed aggregations, as well as the position of the aggregates (in each shelter, the number of individual per aggregation and the number of isolated individuals. In order to test the hypothesis of conditioning of disks by chemicals compounds, the experiment II was carried out. All the individuals were transferred to other boxes with humus, three new disks and the disk containing the larger aggregate after the 168 hours of the experiment I (denominated conditioned disk. We verified, after 24 and 48 hours, the number of individuals below the conditioned disk. In experiment I, aggregations were observed in every used box and in every time intervals. In all boxes, there was a significant increase in the number of individuals per aggregation and a reduction in the number of isolated individuals until the end of the experiment (ANOVA, p < 0.005. In experiment II, after 24 hours, six from 15 boxes presented aggregations under the conditioned disk, and after 48 hours, seven boxes presented aggregations under conditioned disk. These were the aggregations with a larger quantity of individuals, which suggests the conditioning of the used disks by some factor, possibly a chemical compound.

  10. Especies nuevas del género Gibberula (Mollusca: Cystiscidae de Cuba y Venezuela New species of the genus Gibberula (Mollusca: Cystiscidae from Cuba and Venezuela

    Directory of Open Access Journals (Sweden)

    José Espinosa

    2011-03-01

    Full Text Available Se describen 3 especies nuevas de moluscos marinos: Gibberula palmasola sp. n., recolectada en la vegetación asociada a rocas rodeadas de sedimentos blandos en una laguna costera cercada por mangle en la península de Guanahacabibes, Cuba, y caracterizada por presentar, el animal vivo, la cabeza negra y una distribución típica de bandas negras y pardas con lunares anaranjados en el manto bajo la concha; Gibberula dosmosquises sp. n., recolectada en fondos rocosos del Caribe insular de Venezuela, se caracteriza por una discreta coloración del manto y un patrón de manchas en el pie, y Gibberula thetisae sp. n, proveniente de los pastos marinos del golfo de Batabanó, Cuba, con 3 pliegues en la columela, el último muy débil, y un labio externo casi cortante, caracteres que permiten separarla de todas las demás especies conocidas en el área antillana, aunque se desconozca la anatomía del animal. Se discute la lista de especies válidas del género para Cuba y Venezuela, y se hacen adiciones y consideraciones al complejo de especies en torno a Gibberula ubitaensis Espinosa y Ortea, 2000.Three new species of marine molluscs are described. Gibberula palmasola new species, collected in vegetation associated with rocks surrounded by soft sediments in a coastal lagoon surrounded by mangroves in Guanahacabibes Peninsula, Cuba, and characterized by a black head and typical distribution of black and brown bands and orange spots in the mantle. Gibberula dosmosquises new species, collected in rocky bottoms of a Caribbean island from Venezuela, characterized by a simple staining in the mantle and a pattern of spots on the foot, and Gibberula thetisae new species, from sea grass in the gulf of Batabano, Cuba, with shell having 3 columellar folds, the last very weak, and a sharp outer lip; although, its anatomy is not known, these conchological characters separate it from all other known species in the Antilles. Aditionally, the list of valid species for Cuba and Venezuela is discussed and some considerations about Gibberula ubitaensis Espinosa y Ortea, 2000 species complex are given.

  11. The relative availability of inorganic carbon and inorganic nitrogen influences the response of the dinoflagellate Protoceratium reticulatum to elevated CO2

    Czech Academy of Sciences Publication Activity Database

    Pierangelini, M.; Raven, J.A.; Giordano, Mario

    2017-01-01

    Roč. 53, č. 2 (2017), s. 298-307 ISSN 0022-3646 Institutional support: RVO:61388971 Keywords : cell composition * CO 2 * dinoflagellate Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.608, year: 2016

  12. Influence of a non-copper algicide on the cyanobacterium, Nostoc spongiaeforme, and the green alga, Hydrodictyon reticulatum, in field and laboratory experiments

    Science.gov (United States)

    Cyanobacteria grow in California rice fields where they form large mats that may smoother seedlings or cause them to dislodge, resulting in yield loss. The most troublesome species is Nostoc spongiaeforme. It is very difficult to control using currently accepted methods, i.e., aerial applications of...

  13. Identification of quantitative trait loci (QTL) controlling cold tolerance in chickpea recombinant RIL population (CRIL2) from Cicer arietinum L. x Cicer reticulatum

    Science.gov (United States)

    Published yields for chickpea (Cicer arietinum L.) are higher when the crop is planted in the fall rather than in the spring seasons (Singh et al 1989, Singh et al 1997). Because of its lack of cold hardiness alleles to survive freezing temperatures, chickpea is planted in the spring in temperate re...

  14. Removal of Molluscicidal Bait Pellets by Earthworms and its Impact on Control of the Gray Field Slug, Derocerus reticulatum Mueller, in Western Oregon Grass Seed Fields

    Science.gov (United States)

    Slugs are common pests of grass seed fields in western Oregon and are currently controlled using bait pellets that often fail to give adequate protection. Here we demonstrate the loss of bait pellet products to earthworms and its adverse effects on controlling slugs. Three years of field and greenho...

  15. Systematic reviews on the Mesodesmatidae (Mollusca, Bivalvia) I. The Genus Monterosatus Beu, 1971

    NARCIS (Netherlands)

    Rooij-Schuiling, de L.A.

    1977-01-01

    In trying to identify a small Mesodesma from West Irian, New Guinea, much material in the collections of several museums was studied. As a guide for the identification I at first used the revision of the Mesodesmatidae by Lamy (1914), which is based exclusively on the collections of the Parisian

  16. A biomechanical model of rock drilling in the piddock Barnea candida (Bivalvia; Mollusca)

    NARCIS (Netherlands)

    Nederlof, R.; Muller, M.

    2012-01-01

    The bivalve Barnea candida (Pholadacea) makes its burrow in clay, soft rock and peat. Barnea has developed a number of adaptations to accommodate this lifestyle. Four muscles enable burrowing. These are situated around a dorsal pivot in such a way that the piddock is able to rotate the shells around

  17. The influence of thymol+DMSO on survival, growth and reproduction of Bradybaena similaris (Mollusca: Bradybaenidae

    Directory of Open Access Journals (Sweden)

    Paula Ferreira

    2011-04-01

    Full Text Available Bradybaena similaris (Férussac, 1821, commonly known as the Asian trampsnail, is a terrestrial snail native to Asia, introduced in other regions of the world. In Brazil, populations of this land snail are distributed from the state of Amapá in the North to Rio Grande do Sul in the South. This species acts as an intermediate host for parasites and is a difficult-to-control agricultural pest as well, causing great losses to crops and ornamental plant cultivation. This land snail is easily reared in the laboratory and has been successfully used as a biological model in studies that aim at verifying molluscicidal effects of plant extracts. Several studies have demonstrated that B. similaris, like many other species of land and freshwater snails, is physiologically adapted to survival over transitory unfavorable environmental conditions. Moreover, this species seems to have a life history strategy characterized by a short life span and a maximal opportunistic reproductive effort during transient favorable periods. Such biological features may potentially lead to the inefficacy of control attempts and, simultaneously, make this species able to repopulate sites previously treated with biocides. For this reason, studies that aim at verifying the effect of molluscicides on the reproduction, growth and survival of molluscs are greatly required. Molluscicides of plant origin may represent a safe and effective way of controlling these animals. Thymol is a substance of plant origin which has bactericidal, fungicidal and anti-inflammatory properties and has been presented as a promissory biocide of mollusc species. The aim of this work was to assess the molluscicidal property of thymol in combination with DMSO against eggs and adults of B. similaris. During 120 days, we evaluated the effect of thymol+DMSO at different concentrations (2.5 g/L and 5 g/L on the hatching success, hatchling survival, growth and reproduction of B. similaris under laboratory conditions. We tested thymol+DMSO on 160 eggs, 160 10-day-old and 160 30-day-old juveniles. The results showed that thymol+DMSO (5 g/L and 2.5 g/L affected hatching success, acting as an ovicide. The tests with 10-day-old juveniles showed that thymol+DMSO at 2.5 g/L and 5 g/L caused 90 and 100% of mortality, respectively. For the 30-day-old juveniles, thymol+DMSO caused 87.5% of mortality at 5 g/L, and 75% at 2.5 g/L. With regard to growth, the results were not significant. The 10-day-old individuals treated with thymol+DMSO showed only one reproductive event during the 120 days of the experiment. Thymol+DMSO showed molluscicidal and residual activity, which makes evident its potential for controlling snails, and consequently, snail-borne diseases.

  18. Biomphalaria obstructa (Morelet, 1849: a study of topotypic specimens (Mollusca: pulmonata: planorbidae

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1990-12-01

    Full Text Available A description of Biomphalaria obstructa (Morelet, 1849, based on specimens collected at its type locality - isla del carmen, state of Campeche, Mexico - is presented. The Shell is small, 13 mm in diameter, 3.5 mm in width and with 5.75 whorls in the largest specimen, thin, moderately lustrous and translucent, horn-colored. Whorls increasing regularly (neither slowly nor rapidly in diameter, rounded on the periphery side, bluntly angular on the left. Suture well-marked, deeper on the left. Right side widely concave, with first whorl deeply situated and partly hidden by the next. Left side shallower than right one, largely flattened, with first whorl plaintly visible. Aperture roundly heart-shaped, usually in the same plane as the body whorl but somewhat deflected to the left (less frequently to the right in some specimens. Peristome sharp, seldom blunt; a distinct callus on the parietal wall. A number of young shells develop one set (seldom more of apertural lamellae which tend to be resorbed as the shell grows. Absence of renal ridge. Ovotestis with about 70 mostly unbrached diverticula. Seminal vesicle beset with well-developed knoblike to fingerlike diverticula. Vaginal pouch more or less developed. Spermatheca club-shaped when empty, egg-shaped when full, and with intermediate forms between those extremes. Spermathecal body usually somewhat longer than the duct. Prostate with 7 to 20 (mean 12.06 ± 2.51 usually short diverticula which give off plumpish branches spreading out in a fan shape and overlapping to some extent their immediate neighbors. Foremost prostatic diverticulum nearly always partially or completely inserted between the spermathecal body and the uterine wall. Penial sheath consistently narrower and shorter than the prepuce. Muscular coat of the penis consisting of an inner longitudinal and an outer circular layers. Ratios between organ lengths: caudal to cephalic parts of female duct = 0.55 to 1.37 (mean 0.85 +- 0.17; cephalic parte of female duct to penial complex = 1.36 to 2.81 ((mean 1.90 +- 0.33; penial sheath to prepuce = 042 to 0.96 (mean 0.67 +- 0.13. Comparison with Morelet’s type specimens of Planorbis orbiculus and P. retusus points to the identity of those nominal species with B. obstructa.

  19. New records and new species of cones from deeper water off Fiji (Mollusca, Gastropoda, Conidae)

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Röckel, D.; Bouchet, P.

    2008-01-01

    A little less than 100 species of cones are known in the literature from waters around the Fiji islands, all intertidal to subtidal. We report here on the species taken by recent offshore and deep-water benthic sampling expeditions. Samples were taken to depths of 1300 m, although cones were taken

  20. Pseudoglessula Libera, a new Subulinid land snail from Guinea, West Africa (Mollusca, Gastropoda Pulmonata)

    NARCIS (Netherlands)

    Solem, A.; Bruggen, van A.C.

    1976-01-01

    Study of some land snails collected in Guinea, West Africa, by Ms. Diane deVry has led to the description of a new species, Pseudoglessula libera. It is currently known only from several localities near Conakry, but probably has a wide distribution. Detailed comparisons with previously described

  1. Histofisiología del epitelio renal de helix aspersa (mollusca, gastropoda, pulmonata, stylommatophora)

    OpenAIRE

    Sánchez Aguayo, Inmaculada

    1983-01-01

    La excreción es, por definición, la separación de los productos de desecho de los fluidos tisulares y corporales, y su eliminación del organismo. Además, se considera como el resultado de la filtración del líquido de la sangre, de la reabsorción de ciertos compuestos y de la secreción de sustancias en el interior de túbulos excretores. Los productos de desecho son el resultado del metabolismo celular. Aunque en general son productos finales de procesos catabólicos, también pueden incluir ...

  2. Is Galba schirazensis (Mollusca, Gastropoda) an intermediate host of Fasciola hepatica (Trematoda, Digenea) in Ecuador?

    Science.gov (United States)

    Caron, Yannick; Celi-Erazo, Maritza; Hurtrez-Boussès, Sylvie; Lounnas, Mannon; Pointier, Jean-Pierre; Saegerman, Claude; Losson, Bertrand; Benítez-Ortíz, Washington

    2017-01-01

    Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts is relatively scarce in Ecuador. For three months, lymnaeid snails were sampled (n = 1482) in Pichincha Province at two sites located in a highly endemic area. Snails were identified (based on morphology and ITS-2 sequences) and the infection status was established through microscopic dissection and a multiplex polymerase chain reaction (PCR)-based technique. Techniques based on morphology were not useful to accurately name the collected snail species. Comparison with available DNA sequences showed that a single snail species was collected, Galba schirazensis. Live rediae were observed in 1.75% (26/1482) and Fasciola sp. DNA was detected in 6% (89/1482) of collected snails. The COX-1 region permitted identification of the parasite as Fasciola hepatica. The relative sensitivity and specificity of the microscope study, compared to PCR results, were 25.84% and 99.78%, respectively. The mean size of the snails recorded positive for F. hepatica through crushing and microscopy was significantly higher than the mean size of negative snails, but there was no such difference in PCR-positive snails. The role of G. schirazensis as an intermediate host of F. hepatica in Ecuador is discussed and the hypothesis of an adaptation of the parasite to this invasive snail is proposed. For the first time, an epidemiological survey based on molecular biology-based techniques assessed the possible role of lymnaeid snails in the epidemiology of fasciolosis in Ecuador. © Y. Caron et al., published by EDP Sciences, 2017.

  3. Is Galba schirazensis (Mollusca, Gastropoda an intermediate host of Fasciola hepatica (Trematoda, Digenea in Ecuador?

    Directory of Open Access Journals (Sweden)

    Caron Yannick

    2017-01-01

    Full Text Available Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts is relatively scarce in Ecuador. For three months, lymnaeid snails were sampled (n = 1482 in Pichincha Province at two sites located in a highly endemic area. Snails were identified (based on morphology and ITS-2 sequences and the infection status was established through microscopic dissection and a multiplex polymerase chain reaction (PCR-based technique. Techniques based on morphology were not useful to accurately name the collected snail species. Comparison with available DNA sequences showed that a single snail species was collected, Galba schirazensis. Live rediae were observed in 1.75% (26/1482 and Fasciola sp. DNA was detected in 6% (89/1482 of collected snails. The COX-1 region permitted identification of the parasite as Fasciola hepatica. The relative sensitivity and specificity of the microscope study, compared to PCR results, were 25.84% and 99.78%, respectively. The mean size of the snails recorded positive for F. hepatica through crushing and microscopy was significantly higher than the mean size of negative snails, but there was no such difference in PCR-positive snails. The role of G. schirazensis as an intermediate host of F. hepatica in Ecuador is discussed and the hypothesis of an adaptation of the parasite to this invasive snail is proposed. For the first time, an epidemiological survey based on molecular biology-based techniques assessed the possible role of lymnaeid snails in the epidemiology of fasciolosis in Ecuador.

  4. Gonad development during the early life of Octopus maya (Mollusca: Cephalopoda).

    Science.gov (United States)

    Avila-Poveda, Omar Hernando; Colin-Flores, Rafael Francisco; Rosas, Carlos

    2009-02-01

    Gonad development during the early life of Octopus maya is described in terms of histological, morphometric, oocytes growth, and somatic-oocyte relationship data obtained from octopus cultured at the UMDI-UNAM, in Sisal, Yucatan, Mexico. This study is the first publication on gonad development during the early life of Octopus maya. A total of 83 O. maya specimens were used; their sizes ranged from 6.5 to 76 mm of total length (TL), 4 to 28 mm of dorsal mantle length (DML), 2.5 to 20 mm of ventral mantle length (VML), and 0.0180 to 7.2940 g of fixed body weight (fBW). Animals were weighed and measured only after preservation. A loss of 10% of living weight was estimated for juvenile octopuses after formalin preservation. The relation of length to weight (VML, DML, TL/fBW) pooled for both sexes had a strong positive correlation (r), as shown by a potential power function that was quite close to 1. Compound images were produced from numerous microscopic fields. The histological examination revealed that, 4 months after hatching, male octopus (24.5 mm DML and 7.2940 g fBW) were in gonad stages 2 (maturing) to 3 (mature), with spermatogonia and spermatocytes in the tubule wall and abundant spermatids and spermatozoa in the central lumen of the seminiferous tubules, suggesting the occurrence of different phases of gonad development at different maturity stages. In contrast, females (22.5 mm DML and 4.8210 g fBW) at the same time since hatching were immature (stage 1), with many oogonia, few oocytes, and germinal epithelium. This suggests that males reach maturity earlier than females, indicating a probable onset of maturity for males at around 4 months of culture or 8 g of wet body weight. Our results indicate the possibility that the size-at-weight can be recognized early with a degree of certainty that allows the sexes to be separated for culture purposes; but more detailed studies on reproduction in relation to endocrinology and nutrition are needed.

  5. High accumulation of cobalt-60 by the particular organ or part of some species in mollusca

    International Nuclear Information System (INIS)

    Yoshida, Katsuhiko

    1981-01-01

    A large amounts of samples in marine Cephalopoda and Tridacna were sampled in north west pacific ocean, near Japan. The samples were separated into organs or parts for determination of Co-60 concentration. A peculiar accumulation of Co-60 by the branchial heart of Octopus was also recognized in field condition, but it had become apparent that branchial heart of squid had not same ability. Liver of Cephalopoda had the ability to highly accumulate the Co-60 and specific activity of squid was one order highter than Octopus. The concentration of Cobalt-60 in visceral muss kidney of Tridacna maxima lineally increased with increasing shell length but that in other soft parts was kept constant. After examination of the other papers it was assumed that Co-60 highly accumulated in these organs was transfered by the food chain. (author)

  6. Vestigial phragmocone in the gladius points to a deepwater origin of squid (Mollusca: Cephalopoda)

    Science.gov (United States)

    Arkhipkin, Alexander I.; Bizikov, Vyacheslav A.; Fuchs, Dirk

    2012-03-01

    The microstructure of the gladius cone was investigated in six species of nektonic squid: shallow-water Loligo gahi (Loliginidae), pelagic eurybathic Illex argentinus, Todarodes pacificus, Dosidicus gigas (Ommastrephidae), and deepwater Onykia ingens (Onychoteuthidae) and Gonatus antarcticus (Gonatidae) using state-of-the-art microscopy. Apart from L. gahi, all other species had septa-like layers in the gladius cone, which for the first time were investigated in detail and compared with those in extinct Cretaceous belemnites Hibolithes sp. and Pachyteuthis sp., and spirulid Cyrtobelus sp. It was found that the organic layers of the gladius cone in recent squid can be homologized with the organic components of the shell in fossil phragmocone-bearing coleoids. The septa-like layers in modern gladius cones therefore represent a vestigial phragmocone composed of organic septal rudiments of the ancestral phragmocone that has lost the siphuncle and gas-filled chambers. The well-developed rostrum in onychoteuthids and small rostrum of the gladius in ommastrephids and gonatids can be seen as homologous with the belemnoid rostrum, which may indicate a close phylogenetic relationship between belemnites and at least some squid. Possible evolutionary pathways of the reduction of the functional phragmocone in squid ancestors are discussed. Several features such as the loss of shell calcification, deep water speciation, and the structure of the equilibrium organ point to a deep-water origin of squids.

  7. Alien Planorbid (Mollusca, Gastropoda Pulmonata) from South West Africa erroneously recorded as Biomphalaria Pfeifferi

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1974-01-01

    In 1970 I published a record of the freshwater snail Biomphalaria pfeifferi (Krauss, 1848) (fam. Planorbidae) for South West Africa: "Sandamap Farm, Spitzkoppe" (Van Bruggen, 1970: 45, figs. 1-13). Dr. D. S. Brown of the Medical Research Council (London) kindly drew my attention to the fact that

  8. Genetics and shell morphometrics of assimineids (Mollusca, Caenogastropoda, Truncatelloidea) in the St Lucia Estuary, South Africa.

    Science.gov (United States)

    Miranda, Nelson A F; van Rooyen, Ryan; MacDonald, Angus; Ponder, Winston; Perissinotto, Renzo

    2014-01-01

    The Assimineidae are a family of amphibious microgastropods that can be mostly found in estuaries and mangroves in South Africa. These snails often occur in great numbers and are ecologically important to the St Lucia Estuary, which forms a crucial part of the iSimangaliso Wetland Park, a UNESCO World Heritage Site. Genetic and shell morphometric analyses were conducted on individuals collected from nine localities distributed from the northern lake regions to the southern lake and the mouth of the St Lucia estuarine lake. Mitochondrial (COI) and nuclear (28S) DNA was used to construct Bayesian Inference, Neighbour-joining, Maximum Parsimony and Maximum Likelihood trees. Principal Component Analysis and Cluster Analysis were performed on standard shell parameter data. Results indicate that two different taxa are present in St Lucia. The taxon comprising individuals from the South Lake and St Lucia Estuary Mouth is identified as Assiminea cf. capensis Bartsch, in accordance with the latest taxonomic consensus. The taxon comprising assimineid individuals from False Bay, North Lake and South Lake, is here tentatively named "Assiminea" aff. capensis (Sowerby). These two taxa exhibit patterns of spatial overlap that appear to vary depending on environmental parameters, particularly salinity. The need to resolve the complex taxonomy of assimineids is highlighted.

  9. Neuromuscular development of Aeolidiella stephanieae Valdéz, 2005 (Mollusca, Gastropoda, Nudibranchia)

    DEFF Research Database (Denmark)

    Kristof, Alen; Klussmann-Kolb, Annette

    2010-01-01

    ABSTRACT: BACKGROUND: Studies on the development of the nervous system and the musculature of invertebrates have become more sophisticated and numerous within the last decade and have proven to provide new insights into the evolutionary history of organisms. In order to provide new morphogenetic ...

  10. The Bulimulidae (Mollusca: Pulmonata) from the Región de Atacama, northern Chile.

    Science.gov (United States)

    Araya, Juan Francisco

    2015-01-01

    The bulimulid genus Bostryx Troschel, 1847 is the most species-rich genus of land snails found in Chile, with the majority of its species found only in the northern part of the country, usually in arid coastal zones. This genus has been sparsely studied in Chile and there is little information on their distribution, diversity or ecology. Here, for the first time, a formal analysis of the diversity of bulimulids in the Región de Atacama, northern Chile, is reported. Of the seventeen species recorded for the area, most of them were efectively found in the field collections and one record was based on literature. Five taxa are described as new: Bostryx ancavilorum sp. nov., Bostryx breurei sp. nov., Bostryx calderaensis sp. nov., Bostryx ireneae sp. nov. and Bostryx valdovinosi sp. nov., and the known geographic distribution of seven species is extended. Results reveal that the Región de Atacama is the richest region in terrestrial snails in Chile, after the Juan Fernández Archipelago. All of the terrestrial molluscan species occurring in the area are endemic to Chile, most of them with restricted geographic distributions along the coastal zones, and none of them are currently protected by law. Further sampling in northern Chile will probably reveal more snail species to be discovered and described.

  11. Invertebrate shells (mollusca, foraminifera) as pollution indicators, Red Sea Coast, Egypt

    Science.gov (United States)

    Youssef, Mohamed; Madkour, Hashem; Mansour, Abbas; Alharbi, Wedad; El-Taher, Atef

    2017-09-01

    To assess the degree of pollution and its impact on the environment along the Red Sea Coast, the most abundant nine species of recent benthic foraminifera and three species of molluscan shells have been selected for the analysis of Fe, Mn, Zn, Cu, Pb, Ni, Co, and Cd concentrations. The selected foraminiferal species are: Textularia agglutinans, Amphispsorus hemprichii, Sorites marginalis, Peneroplis planatus, Borelis schlumbergeri, Amphistegina lessonii, Ammonia beccarii, Operculina gaimairdi, and Operculinella cumingii. The selected molluscan shells are: Lambis truncata and Strombus tricornis (gastropods) and Tridacana gigas (bivalves). The inorganic material analysis of foraminifera and molluscs from the Quseir and Safaga harbors indicates that foraminifera tests include higher concentrations of heavy metals such as Fe and Mn than molluscan shells. These results are supported by the black tests of porcelaneous foraminifera and reflect iron selectivity. The Cd and Pb concentrations in molluscan shells are high in the El Esh Area because of oil pollution at this site. The Cu, Zn, and Ni concentrations in the studied invertebrates are high at Quseir Harbor and in the El Esh Area because of the strong influence of terrigenous materials that are rich in these metals. The heavy metal contamination is mostly attributed to anthropogenic sources.

  12. Molecular phylogeny of pearl oysters and their relatives (Mollusca, Bivalvia, Pterioidea

    Directory of Open Access Journals (Sweden)

    Tëmkin Ilya

    2010-11-01

    Full Text Available Abstract Background The superfamily Pterioidea is a morphologically and ecologically diverse lineage of epifaunal marine bivalves distributed throughout the tropical and subtropical continental shelf regions. This group includes commercially important pearl culture species and model organisms used for medical studies of biomineralization. Recent morphological treatment of selected pterioideans and molecular phylogenetic analyses of higher-level relationships in Bivalvia have challenged the traditional view that pterioidean families are monophyletic. This issue is examined here in light of molecular data sets composed of DNA sequences for nuclear and mitochondrial loci, and a published character data set of anatomical and shell morphological characters. Results The present study is the first comprehensive species-level analysis of the Pterioidea to produce a well-resolved, robust phylogenetic hypothesis for nearly all extant taxa. The data were analyzed for potential biases due to taxon and character sampling, and idiosyncracies of different molecular evolutionary processes. The congruence and contribution of different partitions were quantified, and the sensitivity of clade stability to alignment parameters was explored. Conclusions Four primary conclusions were reached: (1 the results strongly supported the monophyly of the Pterioidea; (2 none of the previously defined families (except for the monotypic Pulvinitidae were monophyletic; (3 the arrangement of the genera was novel and unanticipated, however strongly supported and robust to changes in alignment parameters; and (4 optimizing key morphological characters onto topologies derived from the analysis of molecular data revealed many instances of homoplasy and uncovered synapomorphies for major nodes. Additionally, a complete species-level sampling of the genus Pinctada provided further insights into the on-going controversy regarding the taxonomic identity of major pearl culture species.

  13. Molecular phylogeny of pearl oysters and their relatives (Mollusca, Bivalvia, Pterioidea)

    Science.gov (United States)

    2010-01-01

    Background The superfamily Pterioidea is a morphologically and ecologically diverse lineage of epifaunal marine bivalves distributed throughout the tropical and subtropical continental shelf regions. This group includes commercially important pearl culture species and model organisms used for medical studies of biomineralization. Recent morphological treatment of selected pterioideans and molecular phylogenetic analyses of higher-level relationships in Bivalvia have challenged the traditional view that pterioidean families are monophyletic. This issue is examined here in light of molecular data sets composed of DNA sequences for nuclear and mitochondrial loci, and a published character data set of anatomical and shell morphological characters. Results The present study is the first comprehensive species-level analysis of the Pterioidea to produce a well-resolved, robust phylogenetic hypothesis for nearly all extant taxa. The data were analyzed for potential biases due to taxon and character sampling, and idiosyncracies of different molecular evolutionary processes. The congruence and contribution of different partitions were quantified, and the sensitivity of clade stability to alignment parameters was explored. Conclusions Four primary conclusions were reached: (1) the results strongly supported the monophyly of the Pterioidea; (2) none of the previously defined families (except for the monotypic Pulvinitidae) were monophyletic; (3) the arrangement of the genera was novel and unanticipated, however strongly supported and robust to changes in alignment parameters; and (4) optimizing key morphological characters onto topologies derived from the analysis of molecular data revealed many instances of homoplasy and uncovered synapomorphies for major nodes. Additionally, a complete species-level sampling of the genus Pinctada provided further insights into the on-going controversy regarding the taxonomic identity of major pearl culture species. PMID:21059254

  14. Variações anatômicas em Lymnaea columella (Mollusca, Gastropoda

    Directory of Open Access Journals (Sweden)

    Marlene T. Ueta

    1977-12-01

    Full Text Available Foram estudadas variações anatômicas de espécimes de L. columella coletados de diferentes criadouros situados em diversos Municípios do Estado de São Paulo: Campinas, Americana, Atibaia, Pirassununga, Caçapava e Taubaté. As comparações morfométricas foram baseadas em estudos do aparelho genital, rim e rádula. Foram medidos, para cada criadouro, os comprimentos do conjunto útero-vagina, dueto da espermateca, prepúcio e bainha do pênis. Foram ainda calculados os índices de relação entre bainha do pênis/prepúcio e estabelecidos os coeficientes de correlação entre comprimento da concha e comprimento do prepúcio. Cortes longitudiais do complexo peniano foram também objeto de estudo. Em relação a rádula foram determinados o número de fileiras transversais e o número de dentes por fileira, e estabelecida uma fórmula radular aproximada para os diversos criadouros.Soft parts of Lymnaea columella from ten populations from the State of São Paulo were studied in order to determine morphometric variations. These morphometric cornparisons were made upon reproductive system, kidney and radula of snail samples collected in different municipalities: Campinas, Americana, Atibaia, Pirassununga, Caçapava and Taubaté. Length measurementes of uterus, duct of spermatheca, prepuce and penis sheath were taken; the ratio penis sheath/prepuce and correlation coefficients between length of shell and length of prepuce were established. Longitudinal sections of penial complex were also studied. The number of trans verse rows, number of teeth per rows and the length of shell were determined. For each sample, the radular formula was indicated.

  15. Studies on the physiology and endocrinology of reproduction of Helisoma duryi (Mollusca: Pulmonata)

    Energy Technology Data Exchange (ETDEWEB)

    Miksys, S.L.

    1987-01-01

    Helisoma duryi is a hermaphroditic, freshwater, pulmonate snail native to North America. It has been proposed as a biological control agent against snail intermediate hosts of Schistosoma sp., a parasitic trematode in man. Very little is known of the physiology and endocrinology of reproduction of H. duryi. This thesis investigates vitello-genesis, endocrine control of the synthesis of albumen, a nutrient-rich fluid catabolized by developing embryos, and the possible endocrine role of the gonad. Light and electron microscopy, chemical extraction, energy dispersive X-ray analysis, and radioimmunoassay are used to identify the yolk protein ferritin. It is proposed that ferritin synthesis, and its circulating levels, are regulated, probably indirectly, by a gonadal factor released into the blood. The rate of synthesis of albumen polysaccharides can be monitored in vitro by providing albumen gland explants with the precursor /sup 14/C-glucose and measuring /sup 14/C-polysaccharide produced. The basal synthetic activity of the gland reflects the reproductive activity of the snail.

  16. Stunting of the penis in Heleobia parchappii (Mollusca: Cochliopidae) and its relationship with parasitism.

    Science.gov (United States)

    Merlo, Matías J; Parietti, Manuela; Etchegoin, Jorge A

    2017-02-08

    Penis anatomy is used to discriminate species of gastropods belonging to the family Cochliopidae; however, this characteristic may be affected by the presence of parasites. To evaluate the possible effect of parasites on penis length and number of papillae in Heleobia parchappii, 195 males were collected from the Nahuel Rucá Lagoon, Argentina. Male snails were only infected by trematode digeneans (total prevalence 45.13%). Three out of 9 species of digeneans registered showed prevalence values higher than 10%: Microphallus szidati, M. simillimus, and Notocotylidae sp. 1. The penis length of non-parasitized males and those parasitized by M. szidati and M. similimus increased with increased snail length; however, this increase was lower in infected snails. In the case of snails infected with Notocotylidae sp. 1, no relationship between shell length and penis length was apparent. Differences in the life cycles of these 3 digeneans could explain the null or lower penis growth rate in relation to host body growth. In contrast, no change was observed in the number of penial papillae of H. parchappii when these snails were infected by larval digeneans compared to those that were not infected. This indicates that penial papillae may be a more stable characteristic than penis length to discriminate between species within the Cochliopidae. The study of penial papillae should be central in the taxonomy and identification of new species within the Cochliopidae, as well as in previously described species.

  17. A new record of marine wood-borer (Mollusca: Teredinidae) from waters off Bombay

    Digital Repository Service at National Institute of Oceanography (India)

    Raveendran, T.V.; Wagh, A.B.

    The occurrence of Teredona princesae (Sivickis) has been reported for the first time from the Exclusive Economic Zone (EEZ) off Bombay. A brief description of the pallet and distribution of this species is presented...

  18. Integrative taxonomy of the genus Onchidium Buchannan, 1800 (Mollusca, Gastropoda, Pulmonata, Onchidiidae

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    Benoît Dayrat

    2016-11-01

    Full Text Available In an effort to clarify the species diversity of onchidiid slugs, the taxonomy of the genus Onchidium Buchannan, 1800 is revised using an integrative approach. New, fresh specimens were collected in a large number of places, including type localities. The genus Onchidium is redefined here as a clade including only three species which are strongly supported by both morphological and molecular data. All three species were already named: the type species O. typhae Buchannan, 1800, O. stuxbergi (Westerlund, 1883, and O. reevesii (J.E. Gray, 1850. With the exception of a re-description of O. typhae published in 1869, all three species are re-described here for the first time. First-hand observations on the color variation of live animals in their natural habitat are provided. The anatomy of each species is described. Important nomenclatural issues are addressed. In particular, Labella Starobogatov, 1976 is regarded as a junior synonym of Onchidium and Labella ajuthiae (Labbé, 1935 and O. nigrum (Plate, 1893 are regarded as junior synonyms of O. stuxbergi. The nomenclatural status of several other species names is discussed as well. Many new records are provided across South-East Asia and precise ranges of geographic distributions are provided for the genus Onchidium and its three species. Distinctive features that help distinguish the genus Onchidium from other onchidiids are provided, as well as an identification key for the three species.

  19. THE BIOLOGY OF FISSURELLA MAXIMA SOWERBY (MOLLUSCA: ARCHAEOGASTROPODA) IN NORTHERN CHILE. 2. NOTES ON ITS REPRODUCTION.

    Science.gov (United States)

    Bretos, Marta; Tesorieri, Italo; Alvarez, Luis

    1983-12-01

    For 14 months, monthly samples were collected to study reproduction in Fissurella maxima at Huayquique. Results indicate that F. maxima is a dioecious species; no sign of hermaphroditism has been observed. The sex ratio is 1:1 in the different size classes analyzed. Ovaries are green and testis are median brown to yellowish white. Eggs in the ovary measure from 120-280 µ without envelopes. The gonads are parasitized by adult digenea trematods of the genus Proctoeces. Some effects of parasitism are discussed. Variations in mean monthly gonadosomatic index suggest that there is a main spawning period in late November-December (late spring-early summer) and a secondary period in July-August (winter). Fluctuations in mean gonad index show a close correlation with sea water temperature variations. The youngest mature specimens detected were about 5 cm in shell length (over two years old), but the majority of mature animals were over 6.5 cm.

  20. Cellular biomarker responses of limpets (Mollusca as measure of sensitivity to cadmiumcontamination

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    Koot Reinecke

    2008-09-01

    Full Text Available Due to the availability and chemical nature of some heavy metals, sub-lethal toxicant levels may persist in the ocean waters and may cause physiological problems and toxicity in invertebrates and other marine organisms. Although studies of metal concentrations in False Bay showed relatively low mean concentrations of Cd, invertebrates such as molluscs, crustaceans and many other groups are able to accumulate high levels of heavy metals in their tissues and still survive in the heaviest polluted areas. They can accumulate numerous pollutants from natural waters in quantities that are many orders of magnitude higher than background levels. Bioaccumulation ofcadmium in intertidal species could cause stress which may be measurable at the cellular level. A variety of limpet species that may serve as suitable ecotoxicological monitoring species occur in abundance on rocky shores along the South African coastline. The aim of this study was to obtain sensitivity data which could contribute to the selection of a suitable monitoring species and the eventual establishment of a species sensitivity distribution model (SSD with a biomarker responseas endpoint. The limpets Cymbula oculus, Scutellastra longicosta, Cymbula granatina and Scutellastragranularis as well as water samples were collected at two localities in False Bay, South Africa. Analysis of water and biological samples were done by atomic absorption spectrometry. Exposures were done to three different sublethal concentrations of cadmium in the laboratory in static flow tanks over three days. There was a moderate increase in cadmium body concentrations over time. Results obtained at three exposure concentrations showed no significant differences in metal concentrations between the different C. oculus samples. Significant differences were obtained between the control and the exposure groups for each exposure time except between the control and the 1mg/L CdCl2 exposure group after 24 and 72 hours of exposure. Cd body concentrations(soft tissue varied between 4.56 and 21.41µg/g (wet mass.Mean Cd concentrations in soft tissue of S. longicosta was considerably lower (varying between 1.18 and 19.58 µg/g Cd than in the tissues of C. oculus. The control group differed significantly from the 0.8 and 1 mg/L CdCl2 exposures after 48 and 72 hours. Mean Cd body concentrations in S. granular is were the highest of all exposed species, reaching a level of 148 µg/g Cd at the highest exposure concentration and differed significantly from the means of the other samples of the 0.8 mg/L CdCl2 exposure group after 72 hours and from the 1 mg/L CdCl2 group after 24 hours. Significant differences were also obtained between theCd body concentrations of C. granatina for the three exposure concentrations and three exposure times. Lysosomal membrane integrity was determined for both exposed and control animals, using the neutral red retention assay. Three of the four species showed a significant decrease in retention times with an increase in Cd concentration. Inter-species differences in sensitivity to environmentally relevant cadmium concentrations were reflected in the biomarker responses. Based on reduction of NRR times, the order of relative sensitivity to cadmium was S. granularis >C. oculus> S. longicosta.> C.granatina. 

  1. One hundred years after Pinctada: an update on alien Mollusca in Tunisia

    Directory of Open Access Journals (Sweden)

    M. ANTIT

    2011-04-01

    The occurrence of aliens in Tunisia is balanced between presumably Lessepsian species of tropical Indo-Pacific origin, and species from other sources including species from the Tropical Atlantic introduced through shipping. Nevertheless there is a prevalence of Lessepsian species towards the Gulf of Gabes in the south, whereas the shipping activity in Tunis harbour may be the main pathway of introduction in the north.

  2. Comparative morphology among representatives of main taxa of Scaphopoda and basal protobranch Bivalvia (Mollusca

    Directory of Open Access Journals (Sweden)

    Luiz Ricardo L. Simone

    2009-01-01

    Full Text Available This study deals with detailed morphology and anatomy of 4 species of Scaphopoda and 5 species of protobranch Bivalvia. Both classes are traditionally grouped in the taxon Diasoma, which has been questioned by different methodologies, such as molecular and developmental. This study is developed under a phylogenetic methodology with the main concern in performing it in an intelligible and testable methodology. The analyzed Scaphopoda species came from the Brazilian coast and belong to the family Dentaliidae [(1 Coccodentalium carduus; (2 Paradentalium disparile] and Gadiliidae; [(3 Polyschides noronhensis, n. sp. from Fernando de Noronha Archipelago; (4 Gadila braziliensis]. These species represent the main branches of the class Scaphopoda. From protobranch bivalves, representatives of the families Solemyidae [(5 Solemya occidentalis, from Florida; S. notialis, n. sp. from S.E. Brazil], Nuculanidae [(6 Propeleda carpentieri from Florida], and Nuculidae [(7 Ennucula puelcha, from south Brazil] are included. These species represent the main branches of the basal Bivalvia. The descriptions on the anatomy of S. occidentalis and of P. carpentieri are published elsewhere. The remaining are included here, for which a complete taxonomical treatment is performed. Beyond these species, representatives of other taxa are operationally included as part of the ingroup (indices are then shared with them, as a procedure to test the morphological monophyly of Diasoma. These taxa are: two lamellibranch bivalves [(8 Barbatia - Arcidae; (9 Serratina - Tellinidae; both published elsewhere;, and Propilidium (10 Patellogastropoda, and (11 Nautilus, basal Cephalopoda, based on basal taxa. The effective outgroups are (12 Neopilina (Monoplacophora and (13 Hanleya (Polyplacophora. The phylogenetic analysis based on morphology revealed that the taxon Diasoma is supported by 14 synapomorphies, and is separated from Cyrtosoma (Gastropoda + Cephalopoda. Although they are not the main goal of this paper, the taxa Scaphopoda and Bivalvia are supported by 8 and by 7 synapomorphies respectively. The taxon Protobranchia resulted paraphyletic. Both scaphopod orders resulted monophyletic. The obtained cladogram is: ((((Coccodentalium carduus - Paradentalium disparile (Polyschides noronhensis - Gadila brasiliensis ((Solemya occidentalis - S. notialis (Propeleda carpenteri (Ennucula puelcha (Barbatia cancellaria - Serratina capsoides (Propilidium curumim - Nautilus pompilius - Lolliguncula brevis.Este estudo analisa a morfologia e anatomia detalhadas de 4 espécies de Scaphopoda e 5 espécies de bivalves protobrânquios. Ambas as classes são tradicionalmente agrupadas no táxon Diasoma, o qual vem sendo questionado por diferentes metodologias, tais como molecular e de desenvolvimento. Este estudo é desenvolvido sob uma metodologia filogenética, a qual a maior preocupação é fornecer um procedimento inteligível e testável. As espécies de Scaphopoda analisadas provieram da costa brasileira e pertencem à família Dentaliidae [(1 Coccodentalium carduus; (2 Paradentalium disparile] e Gadilidae [(3 Polyschides noronhensis, n. sp. do Arquipélago de Fernando de Noronha; (4 Gadila braziliensis]. Estas espécies representam os ramos principais da classe Scaphopoda. Dos bivalves protobrânquios, representantes das famílias Solemyidae [(5 Solemya occidentalis, da Flórida; S. notialis, n. sp. do S.E. Brasil], Nuculanidae [(6 Propeleda carpentieri, da Flórida] e Nuculidae [(7 Ennucula puelcha, do sul do Brasil] são incluídos. Estas espécies representam os principais ramos dos bivalves basais. As descrições anatômicas de S. occidentalis e de P. carpentieri estão sendo publicadas em outro artigo, as das demais espécies estão incluídas neste, o qual também inclui um completo tratamento taxonômico. Além dessas espécies, representantes de outros táxons são operacionalmente incluídos como parte do ingroup (então os índices são compartilhados com eles, um procedimento visando testar a monofilia morfológica de Diasoma. Esses táxons são 2 bivalves lamelibrânquios [(8 Barbatia - Arcidae; (9 Serratina - Tellinidae; ambos publicados em artigos a parte]; Propilidium (10 Patellogastropoda e (11 Nautilus, Cephalopoda basal, baseados em táxons basais. Os outgroups efetivos são (12 Neopilina (Monoplacophora e (13 Hanleya (Polyplacophora. A análise filogenética baseada na morfologia revelou que o táxon Diasoma é suportado por 14 sinapomorfias, sendo separada de Cyrtosoma (Gastropoda + Cephalopoda. Embora não sendo o principal enfoque do presente artigo, os táxons Scaphopoda e Bivalvia são suportados por 8 e por 7 sinapomorfias respectivamente. O táxon Protobranchia resultou parafilético. O cladograma obtido é: ((((Coccodentalium carduus - Paradentalium disparile (Polyschides noronhensis - Gadila brasiliensis ((Solemya occidentalis - S. notialis (Propeleda carpenteri (Ennucula puelcha (Barbatia cancellaria - Serratina capsoides (Propilidium curumim - Nautilus pompilius - Lolliguncula brevis.

  3. [Reproductive aspects of Pomacea flagellata (Mollusca: Ampullariidae) at Bacalar lagoon, Quintana Roo, México].

    Science.gov (United States)

    Oliva-Rivera, José J; Ocaña, Frank A; Navarrete, Alberto de Jesús; Carrillo, Rosa M de Jesús; Vargas-Espósitos, Abel A

    2016-12-01

    The freshwater snail Pomacea flagellata is native from Southeastern Mexico. Studies about this species are scarce and none has treated their reproduction. This snail has been exploited at Bacalar lagoon for many years, leading to a significant decrease in their abundance and currently, a permanent ban was proposed by the government. This work aimed to assess the temporal variations of mating frequency and the abundance of egg clutches of P. flagellata at Bacalar lagoon, as well as their relation with snails density and environmental variables. Sampling was done during the three climatic seasons: Rainy (July, August and September/2012), North or Cold fronts (December/2012 and January and February/2013) and Dry (March, April and May/2013) in 12 sampling stations located along the Bacalar lagoon. On each station a transect of 100 m length was set parallel to the edge, and the number of fresh egg clutches (pink color) laid over vegetation, rocks or manmade structures, were counted. In the water, three 50 x 2 m transects were set and the number of snails were counted as well as the mating frequency. Density of snails varied significantly among seasons, decreasing from the rainy to the dry season. There were no significant differences of snail abundance among months, nested in climatic seasons (ANOVA, p>0.05). During the rainy season the mating frequency was significantly higher than in the Norths, meanwhile in the dry season no mating were registered (Kruskal-Wallis, p˂0.05). Eggs clutches appeared from July to March. Density of egg clutches presented no differences between the Rainy and the North seasons (2.72 and 2.93 clutches/m, respectively), nonetheless during the dry season abundance of egg masses was significantly lower (0.1 clutches/m) (H, p˂0.05). Mating frequency was related with snail abundance (rs= 0.26; p<0.05) and water temperature (rs= 0.34; p<0.05) and the abundance of egg masses is related with snail abundance (rs= 0.46; p<0.05). In general, we observed that reproductive activity of P. flagellata at Bacalar lagoon is related with the warmer months and with higher rainfall. This finding is relevant to support the management of this resource in the region, so that to implement any management arrangement they must be aware that a temporal ban is necessary during the reproductive season at least.

  4. A molecular method to detect and identify the native species of southwestern Atlantic Crassostrea (Mollusca: Ostreidae

    Directory of Open Access Journals (Sweden)

    Sandra Ludwig

    2011-08-01

    Full Text Available Among oysters, species of Crassostrea (Sacco, 1897 are the most attractive to aquaculture. In Brazil, the genus is represented by C. rhizophorae (Guilding, 1828 and C. brasiliana (Lamarck, 1819. Because the maturation and breeding technology is not well developed for these species, aquaculturists need a reliable method to decide the correct time to place spat collectors in the field, and to identify both species, which are morphologically similar. In this study a specific Multiplex PCR protocol was developed, using one pair of universal primers from 18S rDNA as a positive control and a pair of specific primers for each target species. The sensitivity and specificity of the protocol was evaluated. It detected C. rhizophorae DNA in low concentrations, and C. brasiliana DNA in even lower concentrations. Further, the Multiplex PCR proved efficient in detecting DNA in concentrations equivalent to that of a single larva of each species, either separated or combined, when mixed with total DNA extract of a plankton sample representing 1000 L of filtered water. Field tests confirmed the applicability of the protocol, which holds the promise to become an important tool for aquaculture or conservation programs, allowing for the continuous monitoring of the life cycle of C. brasiliana and C. rhizophorae, by detecting the right periods of larval release and settlement.

  5. New species of Rissoidae from the Cape Verde Islands (Mollusca: Gastropoda) Part 1

    OpenAIRE

    Moolenbeek, R.G.; Rolán, E.

    1988-01-01

    Sediment samples collected at the Cape Verde Islands contained many interesting micromolluscs. Amongst them, four new species of the family Rissoidae ( Alvania peli, A. nicolauensis, A. stocki and A. planciusi).

  6. Patterns of Diversity of the Rissoidae (Mollusca: Gastropoda) in the Atlantic and the Mediterranean Region

    OpenAIRE

    Sérgio P. Ávila; Jeroen Goud; António M. de Frias Martins

    2012-01-01

    The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species—those living between the intertidal and 50 m depth, and deep species—those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean...

  7. Patterns of diversity of the Rissoidae (Mollusca: Gastropoda) in the Atlantic and the Mediterranean region.

    Science.gov (United States)

    Ávila, Sérgio P; Goud, Jeroen; de Frias Martins, António M

    2012-01-01

    The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species--those living between the intertidal and 50 m depth, and deep species--those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean Sea, belonging to 33 genera. The Mediterranean Sea is the most diverse site, followed by Canary Islands, Caribbean, Portugal, and Cape Verde. The Mediterranean and Cape Verde Islands are the sites with higher numbers of endemic species, with predominance of Alvania spp. in the first site, and of Alvania and Schwartziella at Cape Verde. In spite of the large number of rissoids at Madeira archipelago, a large number of species are shared with Canaries, Selvagens, and the Azores, thus only about 8% are endemic to the Madeira archipelago. Most of the 542-rissoid species that live in the Atlantic and in the Mediterranean are shallow species (323), 110 are considered as deep species, and 23 species are reported in both shallow and deep waters. There is a predominance of nonplanktotrophs in islands, seamounts, and at high and medium latitudes. This pattern is particularly evident in the genera Crisilla, Manzonia, Onoba, Porosalvania, Schwartziella, and Setia. Planktotrophic species are more abundant in the eastern Atlantic and in the Mediterranean Sea. The results of the analysis of the probable directions of faunal flows support the patterns found by both the Parsimony Analysis of Endemicity and the geographical distribution. Four main source areas for rissoids emerge: Mediterranean, Caribbean, Canaries/Madeira archipelagos, and the Cape Verde archipelago. We must stress the high percentage of endemics that occurs in the isolated islands of Saint Helena, Tristan da Cunha, Cape Verde archipelago and also the Azores, thus reinforcing the legislative protective actions that the local governments have implemented in these islands during the recent years.

  8. A new Indo-Pacific Zebina species (Mollusca: Gastropoda: Rissoidae)

    OpenAIRE

    Sleurs, W.J.; Van Goethem, J.L.

    2002-01-01

    A new, widespread, but uncommon Indo-Pacific rissoinine species, Zebina ( ? Zebina) malagazzae sp. nov. is described. It is compared with its morphologically closest relative, the tropical Eastern Pacific species Zebina axeliana (STRONG & HERTLEIN, 1951 ), with the holotype of Zebina constricta LASERON, 1956 from Christmas Island and with Zebina ( ?Zebina) japonica (WEINKAUFF, 1881).

  9. Diversity and biogeography of land snails (Mollusca, Gastropoda) in the limestone hills of Perak, Peninsular Malaysia

    Science.gov (United States)

    Foon, Junn Kitt; Clements, Gopalasamy Reuben; Liew, Thor-Seng

    2017-01-01

    Abstract Limestone hills are now gaining global conservation attention as hotspots for short-range endemic species. Levels of land snail endemism can be high at limestone hills, especially at hill clusters that are geographically isolated. In the State of Perak, Peninsular Malaysia, limestone hills have been opportunistically surveyed for land snails in the past, but the majority have yet to be surveyed. To address this knowledge gap, we systematically surveyed the terrestrial malacofauna of 12 limestone hills that, based on our opinion, are a representation of the limestone land snail assemblages within the State. Our inventory yielded high sampling completeness (>85%). We found 122 species of land snails, of which 34 species were unique to one of the surveyed hills. We identified 30 species that are potentially new to science. The number of land snail species recorded at each hill ranged between 39 and 63 species. Four of the sampled limestone hills namely, Prk 01 G. Tempurung, Prk 55 G. Pondok, Prk 47 Kanthan, and Prk 64 Bt Kepala Gajah, have high levels of species richness and unique species, representing 91% of the total species recorded in this study. We identified two clusters of limestone hills in central Perak with distinct differences in land snail species composition – a northern hill cluster on elevated granite bedrock and southern hill cluster in a low-lying valley surrounded by alluvial soils. As limestone hills continue to be quarried to meet the cement demand, the four identified limestone hills, along with other hills from the two clusters, warrant urgent conservation attention in order to maintain high species diversity within Perak’s terrestrial malacofauna. PMID:28769723

  10. Acanthochitona terezae sp. n., um novo poliplacóforo da costa brasileira (Mollusca, Polyplacophora

    Directory of Open Access Journals (Sweden)

    Orlando Guerra Júnior

    1983-12-01

    Full Text Available O autor descreve uma nova espécie de poliplacóforo (Acanthochitona terezae para o litoral brasileiro, apresenta dados sobre sua morfologia e discute aspectos biogeográficos.The author describes a new species of chiton (Acanthochitona terezae from the coast of Brazil, adducing data on its morphology and biogeographic aspects.

  11. Chitons (Mollusca: Polyplacophora) from the Seychelles with description of a new species

    NARCIS (Netherlands)

    Kaast, P.

    1996-01-01

    Notes are given on nine chiton species, collected mainly during the 'Oceanic Reefs' Expedition to the Seychelles (1992-1993), with some biogeographical observations. Ischnochiton goudi (family Ischnochitonidae) is described as a new species.

  12. Diversidad y microestructura de quitones (Mollusca: Polyplacophora del Caribe de Costa Rica

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    Cedar I García-Ríos

    2011-03-01

    Full Text Available Los poliplacóforos asociados a los arrecifes de coral en la costa caribeña de Costa Rica han sido poco estudiados. El examen del cascajo de coral acumulado en el sublitoral somero, en cuatro estaciones de colección, localizadas en la Provincia de Limón reveló una diversidad de quitones mayor a la documentada. Anteriormente se habían registrado ocho especies para el Caribe costaricense: Ischnochiton erythronotus (C.B. Adams, 1845; Ischnoplax pectinata (Sowerby 1840; Stenoplax boogii (Haddon, 1886; S. purpurascens (C.B. Adams, 1845; Acanthopleura granulata (Gmelin, 1791; Chiton marmoratus Gmelin, 1791; C. tuberculatus Linnaeus, 1758; Acanthochitona rhodea (Pilsbry, 1893. Otras cinco se registran aquí por primera vez: Callistochiton portobelensis Ferreira 1976; Ischnochiton kaasi Ferreira 1987; I. pseudovirgatus Kaas 1972; Acanthochitona balesae Abbott 1954; Cryptoconchus floridanus (Dall 1889.

  13. New records for the shallow-water chiton fauna (Mollusca, Polyplacophora of the Azores (NE Atlantic

    Directory of Open Access Journals (Sweden)

    Sérgio Ávila

    2013-06-01

    Full Text Available Published records, original data from recent field work on all of the islands of the Azores (NE Atlantic, and a revision of the entire mollusc collection deposited in the Department of Biology of the University of the Azores (DBUA were used to compile a checklist of the shallow-water Polyplacophora of the Azores. Lepidochitona cf. canariensis and Tonicella rubra are reported for the first time for this archipelago, increasing the recorded Azorean fauna to seven species.

  14. The first observations of Ischnochiton (Mollusca, Polyplacophora movement behaviour, with comparison between habitats differing in complexity

    Directory of Open Access Journals (Sweden)

    Kiran Liversage

    2017-12-01

    Full Text Available Most species of Ischnochiton are habitat specialists and are almost always found underneath unstable marine hard-substrata such as boulders. The difficulty of experimenting on these chitons without causing disturbance means little is known about their ecology despite their importance as a group that often contributes greatly to coastal species diversity. In the present study we measured among-boulder distributional patterns of Ischnochiton smaragdinus, and used time-lapse photography to quantify movement behaviours within different habitat types (pebble substrata and rock-platform. In intertidal rock-pools in South Australia, I. smaragdinus were significantly overdispersed among boulders, as most boulders had few individuals but a small proportion harboured large populations. I. smaragdinus individuals emerge from underneath boulders during nocturnal low-tides and move amongst the inter-boulder matrix (pebbles or rock-platform. Seventy-two percent of chitons in the pebble matrix did not move from one pebble to another within the periods of observation (55–130 min but a small proportion moved across as many as five pebbles per hour, indicating a capacity for adults to migrate among disconnected habitat patches. Chitons moved faster and movement paths were less tortuous across rock-platform compared to pebble substrata, which included more discontinuities among substratum patches. Overall, we show that patterns of distribution at the boulder-scale, such as the observed overdispersion, must be set largely by active dispersal of adults across the substratum, and that differing substratum-types may affect the degree of adult dispersal for this and possibly other under-boulder chiton species.

  15. The complete mitochondrial genome of the giant African snail Achatina fulica (Mollusca: Achatinidae).

    Science.gov (United States)

    Yang, Huirong; Zhang, Jia-En; Guo, Jing; Deng, Zhixin; Luo, Hao; Luo, Mingzhu; Zhao, Benliang

    2016-05-01

    We present the complete mitochondrial genome of the Achatina fulica in this study. The results show that the mitochondrial genome is 15,057 bp in length, which is comprised of 13 protein-coding genes, 2 rRNA genes, 21 tRNA genes. The nucleotide compositions of the light strand are 35.47% of A, 27.97% of T 19.46% of C, and 17.10% of G. Except the ND3, 7 tRNA, ATP6, ATP8, COX3 and 12S-rRNA on the light strand, the rest are encoded on the heavy strand. Five types of inferred initiation codons are ATA (ND1, ND5), GTG (ND6), ATG (COX3, COX2), ATT (ND4) and TTG (COX1, ND2, ND3, ND4L, ATP6, ATP8, Cytb), and 3 types of inferred termination codons are T (COX3, ND2), TAA (ND1, ND4L, ND5, ND6, ATP6), and TAG (ND3, ND4, COX1, COX2, Cytb, ATP8). There are 24 intergenic spacers and 6 gene overlaps. The tandem repeat sequence (total 52 bp) of (AATAATT)n is observed in 16S-rRNA. Gene arrangement and distribution are inconsistent with the typical vertebrates.

  16. [Occurrence of Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda) in Brazil: intermediate snail host of angiostrongyliasis].

    Science.gov (United States)

    Teles, H M; Vaz, J F; Fontes, L R; Domingos, M de F

    1997-06-01

    Achatina fulica, the intermediate snail host of angiostrongyliasis and also an agricultural pest, is being bred in Brazil for human consumption as "escargot". The snail has escaped from its artificial breeding sites and its dispersal in Itariri country, State of S. Paulo, is reported here for the first time. A. fulica is a transmitter of the rat lungworm Angiostrongylus cantonensis, nematode which causes meningoencephalic angiostrongyliasis; the risks of human contamination are commented on.

  17. Unveiling the oxidative metabolism of Achatina fulica (Mollusca: Gastropoda) experimentally infected to Angiostrongylus cantonensis (Nematoda: Metastrongylidae).

    Science.gov (United States)

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Garcia, Juberlan; Mota, Esther Maria; Castro, Rosane Nora; Pontes, Emerson Guedes; Pinheiro, Jairo

    2018-06-01

    For the first time, alterations in the oxidative metabolism of Achatina fulica experimentally infected with different parasite loads of Angiostrongylus cantonensis were determined. For this, the hemolymph activities of lactate dehydrogenase (LDH) and hexokinase and the glucose concentrations in the hemolymph, as well as the polysaccharide reserves in the digestive gland and cephalopedal mass, were assessed. Additionally, the contents of some carboxylic acids in the hemolymph of infected and uninfected snails were determined by high-performance liquid chromatography (HPLC), permitting a better understanding of the alterations related to the host's oxidative metabolism. As the main results, activation of oxidative pathways, such as the glycolytic pathway, was demonstrated in response to the increase in the activity of hexokinase. This tendency was confirmed by the decrease in the contents of glucose in the hemolymph of parasitized snails, indicating that the infection by A. cantonensis alters the host's metabolism, and that these changes are strongly influenced by the parasite load. This metabolic scenario was accompanied by activation of the anaerobic fermentative metabolism, indicated not only by an increase in the activity of (LDH), but also by a reduction of the content of pyruvic acid and accumulation of lactic acid in the hemolymph of parasitized snails. In this circumstance, maintenance of the host's redox balance occurs through activation of the fermentative pathways, and LDH plays a central role in this process. Together, the results indicate that A. cantonensis infection induces activation of the anaerobic metabolism of A. fulica, characterized not only by the accumulation of lactic acid, but also by a reduction in the pyruvic acid and oxalic acid contents in the hemolymph of the infected snails.

  18. How well-known is the Cephalaspidean fauna (Mollusca: Opisthobranchia) in the Indo-Pacific region?

    DEFF Research Database (Denmark)

    Cedhagen, Tomas

    1998-01-01

    The gastropod group Cephalaspidea contains about 700 recent species worldwide. The status of the research on the group, indicated as the number of described species, in the tropical Indo-Pacific region is compared with other areas. The number ofspecies are 118 in the Indo-Pacific, 168 in Japan...

  19. Using DNA barcoding to differentiate invasive Dreissena species (Mollusca, Bivalvia

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    Jonathan Marescaux

    2013-12-01

    Full Text Available The zebra mussel (Dreissena polymorpha and the quagga mussel (Dreissena rostriformis bugensis are considered as the most competitive invaders in freshwaters of Europe and North America. Although shell characteristics exist to differentiate both species, phenotypic plasticity in the genus Dreissena does not always allow a clear identification. Therefore, the need to find an accurate identification method is essential. DNA barcoding has been proven to be an adequate procedure to discriminate species. The cytochrome c oxidase subunit 1 mitochondrial gene (COI is considered as the standard barcode for animals. We tested the use of this gene as an efficient DNA barcode and found that it allow rapid and accurate identification of adult Dreissena individuals.

  20. Using DNA barcoding to differentiate invasive Dreissena species (Mollusca, Bivalvia).

    Science.gov (United States)

    Marescaux, Jonathan; Van Doninck, Karine

    2013-12-30

    The zebra mussel (Dreissena polymorpha) and the quagga mussel (Dreissena rostriformis bugensis) are considered as the most competitive invaders in freshwaters of Europe and North America. Although shell characteristics exist to differentiate both species, phenotypic plasticity in the genus Dreissena does not always allow a clear identification. Therefore, the need to find an accurate identification method is essential. DNA barcoding has been proven to be an adequate procedure to discriminate species. The cytochrome c oxidase subunit I mitochondrial gene (COI) is considered as the standard barcode for animals. We tested the use of this gene as an efficient DNA barcode and found that it allow rapid and accurate identification of adult Dreissena individuals.

  1. Phylogenetic Diversity of Cephalopoda (Animalia:Mollusca) Along the Saudi Arabian Red Sea Coastline

    KAUST Repository

    Byron, Gordon

    2016-01-01

    ecosystems, serving as part of the food chain and exhibiting population increases due to targeted teleost fisheries and global climate change. In order to assess the biodiversity of Cephalopoda in the Saudi Arabian Red Sea, 87 specimens were collected from 25

  2. Nonhemocyte sources of selected lysosomal enzymes in Biomphalaria glabrata, B. tenagophila and B. straminea (Mollusca: Pulmonata

    Directory of Open Access Journals (Sweden)

    Gary E. Rodrick

    1981-09-01

    Full Text Available The specific activities of acid phosphatase, alkaline phosphatase, β-glucuronidase, lysozymes, glutamate-oxalacetate transaminase and glutamate-pyruvate transaminate were determined in the head-foot and digestive gland of Brazilian Biomphalaria glabrata (Touros, B. tenagophila (Caçapava and B. straminea (Monsenhor Gil. All six enzymes were detected inthe 3000g supernatant. Both cytoplasmic enzymes, glutamate-oxalacetate and glutamate-pyruvate transaminase exhibited the highest specific activities. In the case of the four hydrolytic enzymes assayed, β-glucuronidase exhibited the highest specific activity while lysozyme showed the lowest activity. All six enzymes are thought to be produced by cells within the head-foot and digestive gland of B. glabrata, B. tenagophila and B. straminea.Foram determinadas, na massa cefalopedal e na glândula digestiva de Biomphalaria glabrata de Touros (Rio Grande do Norte B. tenagophila de Cacapava (Sao Paulo e B. straminea de Monsenhor Gil (Piauí, as atividades específicas das seguintes enzimas: fosfatase acida, fosfatase alcalina, beta-glucuronidase, lisozima, transaminase glutâmico-oxalacetica e transaminase glutâmico-piruvica. As seis enzimas referidas foram detectadas no sobrenadante a 3000g. Ambas as enzimas citoplasmaticas - transaminases glutamico-oxalacetica e glutamico-piruvica - mostraram as atividades específicas mais altas. No caso das quatro enzimas hidrolíticas, a beta-glucuronidase revelou a mais alta atividade específica, enquanto a lisozima revelou a mais baixa. E admitido que todas as seis enzimas sao produzidas por celulas presentes na massa cefalopedal e na glândula digestiva das tres especies de moluscos examinadas.

  3. Ross Sea Mollusca from the Latitudinal Gradient Program: R/V Italica 2004 Rauschert dredge samples

    Directory of Open Access Journals (Sweden)

    Claudio Ghiglione

    2013-10-01

    Full Text Available Information regarding the molluscs in this dataset is based on the Rauschert dredge samples collected during the Latitudinal Gradient Program (LGP on board the R/V “Italica” in the Ross Sea (Antarctica in the austral summer 2004. A total of 18 epibenthic dredge deployments/samplings have been performed at four different locations at depths ranging from 84 to 515m by using a Rauschert dredge with a mesh size of 500µm. In total 8,359 specimens have been collected belonging to a total of 161 species. Considering this dataset in terms of occurrences, it corresponds to 505 discrete distributional records (incidence data. Of these, in order of abundance, 5,965 specimens were Gastropoda (accounting for 113 species, 1,323 were Bivalvia (accounting for 36 species, 949 were Aplacophora (accounting for 7 species, 74 specimens were Scaphopoda (3 species, 38 were Monoplacophora (1 species and, finally, 10 specimens were Polyplacophora (1 species. This data set represents the first large-scale survey of benthic micro-molluscs for the area and provides important information about the distribution of several species, which have been seldom or never recorded before in the Ross Sea. All vouchers are permanently stored at the Italian National Antarctic Museum (MNA, Section of Genoa, enabling future comparison and crosschecking. This material is also currently under study, from a molecular point of view, by the barcoding project “BAMBi” (PNRA 2010/A1.10.

  4. Deep-water Drilliinae, Cochlespirinae and Oenopotinae (Mollusca: Gastropoda: Turridae from the Campos Basin, southeast Brazil

    Directory of Open Access Journals (Sweden)

    Raquel Medeiros Andrade Figueira

    2010-08-01

    Full Text Available Samples of a soft-bottom community from the continental slope of Campos Basin, off southeast Brazil, were obtained between 2001 and 2003 by the Research Vessel “Astro-Garoupa” with a 0.25 m2 box corer or by dredging with a Charcot dredge. A total of 177 samples were taken at depths ranging from 700 to 1950 m. Mollusks were present at all of the stations and among Gastropoda the Turridae showed the highest diversity. Within the family Cochlespirinae we found: Leucosyrinx tenoceras (Dall, 1889, L. verrillii (Dall, 1881, expanding the known distribution of the latter species farther south, and L.? subgrundifera (Dall, 1888, which is the first record of this species for the South Atlantic and the shallowest depth at which it has ever been found. Within the family Drilliinae we found Splendrillia centimata (Dall, 1889, also the first record of this species for the South Atlantic and its shallowest depth. Within the subfamily Oenopotinae we describe here three new species in the genus Oenopota Mörch, 1852: O. seraphina n. sp., O. diabula n. sp. and O. carioca n. sp.

  5. Three New Records of Gastropoda (Mollusca) from the Nansha Islands, China

    Science.gov (United States)

    Chen, Zhiyun; Shi, Wei; Gong, Li

    2018-04-01

    The Nansha Islands, China, have extremely high marine biodiversity and hundreds of mollusks have been reported there. Benthos resources investigations of the intertidal and subtidal zone around the Nansha Islands have been continuously performed for decades, and recently, dozens of new species and new records of mollusks have been reported from this area. This paper dealt with three new record species of the Gastropoda from Chinese waters: Cerithium salebrosum Sowerby II, 1855, Vexillum militare (Reeve, 1845) and Vexillum bizonale (Dautzenberg et Bouge, 1923), respectively belonging to three families: Cerithiidae Fleming, 1822, and Costellariidae MacDonald, 1860. All specimens were collected from the Nansha Islands during the benthos resources investigations on the intertidal zone of islands and reefs in the South China Sea in recent years. Diagnosis and geographic descriptions of both genus and species, illustrations of each species were given in this contribution, and discussion of taxonomy, identification features and faunal characteristics were presented. All examined specimens were deposited in the Marine Biodiversity Collections of South China Sea, Chinese Academy of Sciences.

  6. Especies bentónicas de Opisthobranchia (Mollusca: Gastropoda presentes en el litoral del norte peruano

    Directory of Open Access Journals (Sweden)

    Katia Nakamura

    2013-05-01

    Full Text Available El presente trabajo muestra las especies bentónicas de Opisthobranchia registradas para el norte del Perú. El trabajo se basa en la recopilación de la literatura científica disponible para el área de interés. Se presentan las 17 especies reportadas para dicha zona, clasificadas dentro del Grupo Informal Opisthobranchia en 6 clados, 12 familias y 14 géneros. A pesar del alto potencial de diversidad que se le otorga a la costa norte peruana, el número de especies registradas es bajo, debido principalmente al escaso número de exploraciones e investigaciones realizadas.

  7. The shallow-water chitons (Mollusca, Polyplacophora of Caldera, Region of Atacama, northern Chile

    Directory of Open Access Journals (Sweden)

    Juan Francisco Araya

    2015-03-01

    Full Text Available The Molluscan species of the northern littoral of Chile have been sparsely studied. This work reviews for the first time the diversity of polyplacophoran molluscs around the port of Caldera, in the Region of Atacama (26°45’49”S; 70°45’17”W to 27°20’23”S; 70°56’46”W, northern Chile. Eleven species were found in this study: Acanthopleura echinata (Barnes, 1824; Callistochiton pulchellus (Gray, 1828; Calloplax vivipara (Plate, 1899, Chaetopleura peruviana (Lamarck, 1819; Chiton cumingsii Frembly, 1827; Chiton granosus Frembly, 1827; Chiton magnificus Deshayes, 1827; Enoplochiton niger (Barnes, 1824, Radsia barnesii (Gray, 1828, Tonicia atrata (G. B. Sowerby II, 1840 and Tonicia chilensis (Frembly, 1827. All of the species occurring in the area have distributions in the southeastern Pacific Ocean, from Ecuador to central Chile, and three of them are species endemic to the Chilean coasts (Calloplax vivipara, Radsia barnesii, and Tonicia atrata. This diversity of species is comparable to that of better surveyed faunas of central and southern Chile or Patagonia. Of the eleven species recorded, the geographic distribution records for Callistochiton pulchellus, Radsia barnesii and Tonicia atrata are extended, and Calloplax vivipara is found alive again after 40 years, filling a gap in its known distribution. Illustrations of living specimens in their habitat, distribution records and a taxonomic key for all the studied taxa are also provided.

  8. Ueber den begriff "Kinoplasma" in der spermiogenese von Australorbis Glabratus Olivaceus (Mollusca, Pulmonata, Planorbidae

    Directory of Open Access Journals (Sweden)

    Rudolf Barth

    1960-11-01

    Full Text Available Zur Klaerung der Frage, ob der Begriff "Kinoplasma" fuer gewisse, von MERTON (1924,1926, 1930 beobachtete Bildungen an den reifenden Spermiden von pulmonaten Mollusken oder fuer Bestandteile des Cytoplasmas im Sinne von STRASBURGER und SCARTH zu verwenden ist, werden in der vorliegenden Mitteilung die Vorgaenge bei der Spermiohistogenese von Australorbis glabratus olivaceus untersucht. Es ergibt sich: 1. Das von MERTON bezeichnete "Kinoplasma" existiert nicht als solches, es handelt sich bei den von ihm dargestellten Protoplasmabildungen um kugelige, von den Spermiden abgeschnuerte Restkoerper nicht verwendeten Baumaterials, bestehend aus Protoplasma und einigen Mitochondrien. Sie werden von den Naehr- oder Bazalzellen phagozytiert. Der Ausdruck "Kinoplasma" kann nur fuer die submikroskopischen, geformten, faedigen Elemente des Cytoplasmas reserviert bleiben, die den geradlinigen Fall der uebrigen nicht geformten Komponenten bremst oder ablenkt; damit muss das Kinoplasma aber aus dem Begriff des Cytoplasmas herausgenommen werden, da es, wenn auch vermutlich reversibel, eine Differenzierung darstellt. 2. Der Spermienfaden wird von den Centriolen (Axialfilament und den Mitochondrien (zwei peripher gelegene Spiralfilamente, sowie einem Plasmamantel gebildet. 3. Nach Beendigung des Auswachsens der Spermiengeissel, die zu diesem Zeitpunkt nur aus dem Achsenfaden und dem Protoplasmazylinder besteht, setzt sich eine Protoplasmamasse vom Kopf in Richtung zum Geisselende in Bewegung. Sie fuehrt den Golgi-Koerper und sehr viele Mitochondrien mit sich. Aus diesen entwickeln sich Fibrillen, die sich zu den beiden Spiralfilamenten zusammenfuegen. Diese Masse entspricht der von MERTON in seiner Theorie als Kinoplasma bezeichneten Komponente. 4. Die Bewegung dieses Protoplasmateils wird auf den Schub zurueckgefuehrt, den die sich bildenden Fibrillen auf die Mitochondrien ausueben. 5. Die Rueckwaertsbewegung dieses Protoplasmakoerpers beruht wahrscheinlich auf Elastizitaet und Kontraktilitaet des Plasmalemmas. 6. Das zum Kopf zurueckgekehrte Protoplasma wird mit restlichen Mitochondrien als Kugel ausgeschieden und von den Naehrzellen phagocytiert. 7. Der Golgi-Koerper wird vor Beendigung der Protoplasmawanderung bereits in der letzten Haelfte der Geissel eliminiert.

  9. Sea Hare Aplysia punctata (Mollusca: Gastropoda) Can Maintain Shell Calcification under Extreme Ocean Acidification.

    Science.gov (United States)

    Carey, Nicholas; Dupont, Sam; Sigwart, Julia D

    2016-10-01

    Ocean acidification is expected to cause energetic constraints upon marine calcifying organisms such as molluscs and echinoderms, because of the increased costs of building or maintaining shell material in lower pH. We examined metabolic rate, shell morphometry, and calcification in the sea hare Aplysia punctata under short-term exposure (19 days) to an extreme ocean acidification scenario (pH 7.3, ∼2800 μatm pCO 2 ), along with a group held in control conditions (pH 8.1, ∼344 μatm pCO 2 ). This gastropod and its congeners are broadly distributed and locally abundant grazers, and have an internal shell that protects the internal organs. Specimens were examined for metabolic rate via closed-chamber respirometry, followed by removal and examination of the shell under confocal microscopy. Staining using calcein determined the amount of new calcification that occurred over 6 days at the end of the acclimation period. The width of new, pre-calcified shell on the distal shell margin was also quantified as a proxy for overall shell growth. Aplysia punctata showed a 30% reduction in metabolic rate under low pH, but calcification was not affected. This species is apparently able to maintain calcification rate even under extreme low pH, and even when under the energetic constraints of lower metabolism. This finding adds to the evidence that calcification is a largely autonomous process of crystallization that occurs as long as suitable haeomocoel conditions are preserved. There was, however, evidence that the accretion of new, noncalcified shell material may have been reduced, which would lead to overall reduced shell growth under longer-term exposures to low pH independent of calcification. Our findings highlight that the chief impact of ocean acidification upon the ability of marine invertebrates to maintain their shell under low pH may be energetic constraints that hinder growth of supporting structure, rather than maintenance of calcification.

  10. Effekte von Xenohormonen auf die limnischen Invertebraten Gammarus fossarum (Crustacea, Amphipoda) und Marisa cornuarietis (Mollusca, Prosobranchia)

    OpenAIRE

    Schirling, Martin

    2005-01-01

    In dieser Arbeit werden Effekte von Xenohormonen auf Gammarus fossarum und Marisa cornuarietis anhand verschiedener Parameter, auf unterschiedlichen biologischen Ebenen dargestellt. In einem Laborexperiment mit G. fossarum, das Grundlage für weitere Untersuchungen im Rahmen dieser Arbeit war, konnte gezeigt werden, dass sich die Stressproteine hsp90 und hsp70 im Laufe der Oocytenreifung gegenläufig verhalten. Sowohl in einem Freilandversuch, bei dem der Einfluss von Kläranlageneinleitern ...

  11. A new alien snail species from the Eger stream, Hungary (Mollusca, Ampullariidae

    Directory of Open Access Journals (Sweden)

    Frisóczki, B.

    2016-11-01

    Full Text Available Our macrozoobenthon samplings carried out in the Eger stream during 2015–2016 resulted in recording an alien species Marisa cornuarietis (Linneaus, 1758 the giant ramshorn snail which has not been reported so far from outdoorwaters in Hungary. Here we report on collecting several specimens from the urban section of the stream close to the outflow of the Eger thermal spa.

  12. The genus Alvania on the Canary islands and Madeira (Mollusca: Gastropoda), part 2 [final part

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Hoenselaar, H.J.

    1998-01-01

    Five Alvania species from the Canary Islands and the Madeira Archipelago are revised. A new species to science, A. johannae is described and for three species lectotypes are designated. Altogether 13 littoral alvaniids are presently known from this area. Doubtful records are enumerated and a list of

  13. The genus Alvania on the Canary Islands and Madeira (Mollusca: Gastropoda) Part 1

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Hoenselaar, H.J.

    1989-01-01

    Micromolluscs of the family Rissoidae and belonging to the genus Alvania s.l. from the Canary Islands and the Madeira archipelago are revised. For several species the type locality is restricted and lectotypes are designated for Rissoa canadensis d’Orbigny, 1839, R. euchila Watson, 1886, R.

  14. Estudo morfométrico da concha de Lymnaea columella say, 1817 (Mollusca, Gastropoda, Pulmonata

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    Marlene T. Ueta

    1980-12-01

    Full Text Available Foram estudadas variações morfométricas de conchas de L. columella, provenientes de dez criadouros localizados nos seguintes municípios do Estado de São Paulo: - Campinas, Americana, Atibaia, Pirassununga, Caçapava e Taubaté. Foram analisados os diferentes tipos de ambientes onde as limneas são encontradas com maior freqüência, estabelecendo-se a época do ano com maior abundância em espécimes, que correspondeu aos meses de julho a outubro. As medidas nas conhas dos diferentes criadouros referiram-se ao comprimento e largura da concha, comprimento e largura da abertura, comprimento da espira e número de voltas. Foram estabelecidos os coeficientes de correlação e de regressão e realizadas análises de variância entre as medidas tomadas e os índices obtidos da relação entre largura/comprimento da concha. Estas conchas foram comparadas com as de L. columella, L. viator, L. cubensis da coleção do Museu Nacional do Rio de Janeiro. Para a maioria das medidas as conchas mostraram proporções constantes, embora apresentassem diferenças em relação ao desenvolvimento. A maior variação foi observada em relação ao comprimento da espira. As variações morfométricas das conchas foram relacionadas com alguns fatores externos como pH, alcalinidade, dureza e teor da água. Aparentemente apenas a dureza total da água influiu na consistência das conchas.Shells of Lymnaea columella from ten populations from the State of São Paulo were studied to determine morphometric variation. Samples were collected in the following municipalities: Campinas, Americana, Atibaia, Pirassununga, Caçapava and Taubaté. Five measurements were taken from each shell: length and width of the shell, length and width of the aperture and lenght of the spire. Two ratios were also established: width/lenght of the shell and length of the aperture /length of the shell. The numbers of whorls and the length of the shell were also determined. Statistical tests (correlation coeficients, regression, and analysis of variance were used to compare the different samples. Also, com parisons of L. columella shells collected by us were made with those of L. columella, L. viator and L. cubensis from collections deposited in the Museu Nacional, Rio de Janeiro. The results of these studies revealed that in most of the cases the snail populations of different areas were similar, showing constant proportions, but they diverged in their absolute dimensions. Data on aquatic environmental conditions (pH, alkalinity, hardness, and calcium concentration were also obtained. These Chemical factors were examined with respect to shell morphology. Our results revealed that only hardness of water was associated with the robustness of the shells.

  15. Great Lakes DNA barcode reference library: Mollusca, annelida, and minor phyla

    Science.gov (United States)

    In recent years, the research and development of DNA-based tools has improved both their sensitivity and costs. This technology has the potential to be useful in the early detection of aquatic invasive species, and can increase the scope of surveillance compared with traditional ...

  16. The Recent Pectinoidea of the New Zealand region (Mollusca: Bivalvia: Propeamussiidae, Pectinidae and Spondylidae)

    NARCIS (Netherlands)

    Dijkstra, H.H.; Marshall, B.A.

    2008-01-01

    The Recent Pectinoidea of the New Zealand region are reviewed. Eight new species are described from the New Zealand Exclusive Economic Zone: Parvamussium cancellorum, Cyclochlamys austrina, Cc. delli, Cc. irregularis, Cc. munida, Cc. pileolus, Cyclopecten fluctuosus, and Catillopecten tasmani. Nine

  17. Changes in energetic metabolism of Biomphalaria glabrata (Mollusca, Planorbidae in response to exogenous calcium

    Directory of Open Access Journals (Sweden)

    L. D. Silva

    Full Text Available Abstract Calcium is considered an essential element for the metabolism of aquatic snail Biomphalaria glabrata (Say, 1818, intermediate host of Schistosoma mansoni Sambon, 1907 in Brazil, and represents a limiting factor to its distribution and adaptation to the environment. This study investigated the effect of different concentrations of exogenous CaCO3 on the energetic metabolism of B. glabrata for better understanding the physiological interference of chemical elements dissolved in the environment with the physiology of this species. Sixty-day-old snails were distributed into six groups, five exposed to different concentrations of CaCO3 (20, 40, 60, 80 and 100 mg/L and a control group. The exposure to CaCO3 was assessed over time, with analysis of 15 snails of each group in the following intervals: 1, 14, 21 or 30 days for hemolymph extraction. Concentrations of calcium and glucose in the hemolymph were determined by commercial kits, and organic acids were extracted using an ion exchange column and analyzed by high-performance liquid chromatography. Concentration of calcium in the hemolymph showed no significant difference (p>0.05 from the control group and between the concentrations tested. Concentration of glucose decreased (p<0.05 in the treatments of exposure to 20 and 40 mg/L and increased when exposed to 80 and 100 mg/L CaCO3 compared to control and to other concentrations tested over 30 days. The organic acids pyruvate, oxaloacetate, citrate, succinate, fumarate, beta-hydroxybutyrate and lactate presented increased concentrations, while propionate and acetoacetate, decreased concentrations, when exposed to CaCO3 compared to control. Considering the influence of different periods of exposure to CaCO3, on the 14th day, there were stronger alterations in the metabolism of B. glabrata. In conclusion, exposure to CaCO3 reduced the concentration of glucose, which is metabolized into pyruvate, the final product of glycolysis, and also influenced the energetic metabolism pathways, indicating an aerobic or partially anaerobic functioning.

  18. Patterns of Diversity of the Rissoidae (Mollusca: Gastropoda) in the Atlantic and the Mediterranean Region

    Science.gov (United States)

    Ávila, Sérgio P.; Goud, Jeroen; de Frias Martins, António M.

    2012-01-01

    The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species—those living between the intertidal and 50 m depth, and deep species—those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean Sea, belonging to 33 genera. The Mediterranean Sea is the most diverse site, followed by Canary Islands, Caribbean, Portugal, and Cape Verde. The Mediterranean and Cape Verde Islands are the sites with higher numbers of endemic species, with predominance of Alvania spp. in the first site, and of Alvania and Schwartziella at Cape Verde. In spite of the large number of rissoids at Madeira archipelago, a large number of species are shared with Canaries, Selvagens, and the Azores, thus only about 8% are endemic to the Madeira archipelago. Most of the 542-rissoid species that live in the Atlantic and in the Mediterranean are shallow species (323), 110 are considered as deep species, and 23 species are reported in both shallow and deep waters. There is a predominance of nonplanktotrophs in islands, seamounts, and at high and medium latitudes. This pattern is particularly evident in the genera Crisilla, Manzonia, Onoba, Porosalvania, Schwartziella, and Setia. Planktotrophic species are more abundant in the eastern Atlantic and in the Mediterranean Sea. The results of the analysis of the probable directions of faunal flows support the patterns found by both the Parsimony Analysis of Endemicity and the geographical distribution. Four main source areas for rissoids emerge: Mediterranean, Caribbean, Canaries/Madeira archipelagos, and the Cape Verde archipelago. We must stress the high percentage of endemics that occurs in the isolated islands of Saint Helena, Tristan da Cunha, Cape Verde archipelago and also the Azores, thus reinforcing the legislative protective actions that the local governments have implemented in these islands during the recent years. PMID:22693430

  19. The sensorial structures of Spondylus americanus Hermann,1781 (Mollusca: Bivalvia, Spondylidae

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    Marina Gomes Viana

    2007-09-01

    Full Text Available Adult animals of Spondylus americanus were analyzed and specialized sensorial structures, the sensorial papillae and the eyes, were characterized. The sensorial papillae were projections on the edge of the mantle in form of light brown fingers which had function of percepting stimulus coming from the medium. They were constituted by loose conjunctive tissues with longitudinal muscular fibers and externally covered by ciliated cubic epithelium, which presented high amount of melanocytes that gave the coloration of the papillae. The eyes were more complex, being on small stalks histologically similar to the papillae. They exhibited a circular formate and had a metallic blue color. Theses structures were constituted by a corneo epithelium, cornea, lens, retina, basal stalk, periocular band and optical nerve. The eyes were distributed asymmetrically to both valves related with the sedentarism of the species. Right valve presented a smaller number of eyes when compared to left one.Foram examinados exemplares adultos de Spondylus. americanus Hermann, 1781 e estruturas especializadas na percepção de estímulos foram caracterizadas: as papilas sensoriais e os ocelos. As papilas sensoriais são projeções do bordo manto em forma de dedos de cor castanha e com a função de perceber estímulos vindo do meio, são constituídas por tecido conjuntivo frouxo contendo fibras musculares longitudinais e revestidas externamente por epitélio cúbico ciliado, o qual apresenta grande quantidade de melanócitos, que dão a coloração das papilas. Os ocelos são mais complexos, estando sobre pequenos pedúnculos histologicamente semelhante às papilas, têm formato circular e possui cor azul metálica. Constituí-se por um epitélio córneo, córnea, lente, retina, pedúnculo basal, banda periocular e nervo óptico. Os ocelos distribuem-se assimetricamente por ambas as valvas, o que está relacionado com o sedentarismo da espécie. A valva direita apresenta menor número de ocelos quando comparada a esquerda.

  20. Anatomia e histologia do aparelho reprodutor masculino de Pomacea canaliculata (Lamarck, 1822 (Mollusca, Gastropoda, Pilidae

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    Eliana de Fátima Marques de Mesquita

    1990-01-01

    Full Text Available In this paper the authors give an anatomical and histological analysis of the male reproductive system of Pomacea canaliculata (Lamarck, 1822. Anatomically, the testis is better evidentiated than the ovary. In the structure of the testis a great number of very small channels converges to a single one. The male copulatory organs result of transformations that take place in the inner surface on the palial membrane. Histologically, the testis of immature males shows seminiferous ducts with round egg-shaped forms. In their lumens we could notice masses of cells that will originate spermatozoids. The penis has a conjunctive muscular sheath that can be seen in van Gieson's coloured preparations.

  1. Phylogenetic Diversity of Cephalopoda (Animalia:Mollusca) Along the Saudi Arabian Red Sea Coastline

    KAUST Repository

    Byron, Gordon

    2016-12-01

    Although the Red Sea presents a unique environment with high temperature and salinity, it remains an area that is understudied. This lack of information is reflected in many areas, one which is biodiversity. Despite increasing work on biodiversity throughout the Red Sea and an increase in Cephalopoda studies, Cephalopoda in the Red Sea remain underrepresented, which is especially pronounced in molecular analyses. Members of the class Cephalopoda are considered to be major contributors to coral reef ecosystems, serving as part of the food chain and exhibiting population increases due to targeted teleost fisheries and global climate change. In order to assess the biodiversity of Cephalopoda in the Saudi Arabian Red Sea, 87 specimens were collected from 25 reef locations between 17°N and 28°N latitude, as well as from the largest fish market in the Kingdom of Saudi Arabia. Taxonomic identification of specimens was determined using morphological comparisons with previously reported species in the Red Sea and the molecular barcoding region Cytochrome Oxidase I. 84 Red Sea sequences were compared with sequences from GenBank and analyzed using a complement of Neighbor-Joining, Maximum-Likelihood, and Bayesian inference trees. Species complexes were also investigated for Sepia pharaonis and Sepioteuthis lessoniana, which had been previously reported. From 17 cuttlefish, our study yielded three species, two of which matched previously reported species in GenBank. In addition, two distinct clades of Sepia pharaonis were identified. Of 35 squid collected, four species were identified, one of which did not match any other accepted species in literature, while Sepioteuthis lessoniana in the Red Sea formed a distinct clade. From 30 different specimens a total of five genera of Octopoda were present, forming six distinct species. Five Octopoda species collected did not match previously reported species, although many specimens were paralarvae or juveniles, so morphologically we could not compare to previously described species in the Red Sea. Cephalopoda fisheries in the Red Sea is low, and as their populations increase worldwide, this could be a viable fishery for Saudi Arabia. As such, further investigation into the role which cephalopods play in supporting biodiversity in the Red Sea is essential.

  2. Fine structure of the mineralized teeth of the chiton Acanthopleura echinata (Mollusca: Polyplacophora).

    Science.gov (United States)

    Wealthall, Rosamund J; Brooker, Lesley R; Macey, David J; Griffin, Brendan J

    2005-08-01

    The major lateral teeth of the chiton Acanthopleura echinata are composite structures composed of three distinct mineral zones: a posterior layer of magnetite; a thin band of lepidocrocite just anterior to this; and apatite throughout the core and anterior regions of the cusp. Biomineralization in these teeth is a matrix-mediated process, in which the minerals are deposited around fibers, with the different biominerals described as occupying architecturally discrete compartments. In this study, a range of scanning electron microscopes was utilized to undertake a detailed in situ investigation of the fine structure of the major lateral teeth. The arrangement of the organic and biomineral components of the tooth is similar throughout the three zones, having no discrete borders between them, and with crystallites of each mineral phase extending into the adjacent mineral zone. Along the posterior surface of the tooth, the organic fibers are arranged in a series of fine parallel lines, but just within the periphery their appearance takes on a "fish scale"-like pattern, reflective of the cross section of a series of units that are overlaid, and offset from each other, in adjacent rows. The units are approximately 2 microm wide and 0.6 microm thick and comprise biomineral plates separated by organic fibers. Two types of subunits make up each "fish scale": one is elongate and curved and forms a trough, in which the other, rod-like unit, is nestled. Adjacent rod and trough units are aligned into large sheets that define the fracture plane of the tooth. The alignment of the plates of rod-trough units is complex and exhibits extreme spatial variation within the tooth cusp. Close to the posterior surface the plates are essentially horizontal and lie in a lateromedial plane, while anteriorly they are almost vertical and lie in the posteroanterior plane. An understanding of the fine structure of the mineralized teeth of chitons, and of the relationship between the organic and mineral components, provides a new insight into biomineralization mechanisms and controls. Copyright 2005 Wiley-Liss, Inc.

  3. A checklist of land snails from the west coast islands of Sabah, Borneo (Mollusca, Gastropoda

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    Chee-Chean Phung

    2017-05-01

    Full Text Available Sabah, situated in one of the world’s biodiversity hotspots, has the largest number of islands in Malaysia with more than 500 of various sizes and degrees of isolation. However, information on the islands’ biodiversity is limited. This study provides an up-to-date checklist of land snail species found on 24 west coast islands in Sabah. A total of 67 species (nearly 20% of the total number of land snail species in the state representing 37 genera and 19 families is enumerated based on systematic field surveys of 133 sampling plots, BORNEENSIS database records and species checklists published between 2000 and 2016. The number of species on the islands ranges from four to 29. Labuan Island has the highest number of species (29, followed by Tiga Island (25, Mantanani Besar Island (24 and Gaya Island (23. However, the populations of some land snail species may have declined as several previously recorded species on the islands were not found in a recent systematic field sampling. This checklist is provided as a baseline inventory for future island land snail studies and to better inform biodiversity conservation plans of marine parks and other islands on the Sabah west coast.

  4. Biogeographical homogeneity in the eastern Mediterranean Sea - I: the opisthobranchs (Mollusca: Gastropoda from Lebanon

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    F. CROCETTA

    2013-07-01

    Full Text Available A reviewed knowledge of the opisthobranch species from Lebanon (eastern Mediterranean Sea, based on literature records (scattered throughout various papers published over a period of more than 150 years and recently collected material (1999-2002 within the CEDRE framework and other samples, is presented, yielding a total number of 35 taxa recorded from the Lebanese shores identified to species level. Special emphasis has mainly been given to the alien species, for which scattered notes are also given. The known opisthobranch biota is composed of 22 native (~ 63%, 12 alien (~ 34% and one cryptogenic (~ 3% taxa. Eleven of these (Berthella aurantiaca, B. ocellata, Aplysia fasciata, Felimare picta, Felimida britoi, F. luteorosea, F. purpurea, Phyllidia flava, Dendrodoris grandiflora, D. limbata and Aeolidiella alderi constitute new records for the Lebanese fauna, whilst the examined material of a further seven species (Elysia grandifolia, Pleurobranchus forskalii, Aplysia dactylomela, Bursatella leachii, Syphonota geographica, Goniobranchus annulatus, Flabellina rubrolineata anecdotally cited from Lebanon on the basis of the samples here studied, is here first explained. One additional taxon belonging to the genus Haminoea has been identified to genus level only. Despite the searching effort poning the basis of the material analyzed here, data reported clearly suggest that strong investments are still needed for a better understanding of the eastern Mediterranean opisthobranch fauna.

  5. Evolutionary position of Peruvian land snails (Orthalicidae among Stylommatophora (Mollusca: Gastropoda

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    Jorge Ramirez

    2011-07-01

    Full Text Available The genera Bostryx and Scutalus (Orthalicidae: Bulimulinae are endemics from South America. They are mainly distributed on the western slopes of the Peruvian Andes. The goal of the present work was to assess their evolutionary position among the stylommatophoran gastropods based on the 16S rRNA mitochondrial marker. Four sequences were obtained, and along with 28 sequences of other Stylommatophora retrieved from the GenBank, were aligned with ClustalX. The phylogenetic reconstruction was carried out using the methods of Neighbor-Joining, Maximum Parsimony, Maximum Likelihood and Bayesian inference. The multiple sequence alignment had 371 sites, with indels. The two genera of the family Orthalicidae for the first time included in a molecular phylogeny (Bostryx and Scutalus, formed a monophyletic group along with another member of the superfamily Orthalicoidea (Placostylus, result that is comparable with that obtained with nuclear markers. Their evolutionary relationship with other land snails is also discussed.

  6. Caloric variability of Corbicula fluminea (Mollusca, Bivalvia in Rosana Reservoir, Brazil

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    Yara Moretto Bagatini

    2007-01-01

    Full Text Available The purpose of the present study was to investigate temporal and longitudinal variation of caloric density of Corbicula fluminea in Rosana Reservoir. Significant differences concerning the caloric density of C. fluminea were observed throughout the year at the three reservoir sites. The caloric density variation during the year was probably related to reproductive activity, which demanded higher allocation of energy in certain period. The food source used by this species might be an important factor in the caloric value temporal and spatial variation of C. fluminea in Rosana Reservoir.O objetivo deste estudo foi investigar a variação temporal e longitudinal da densidade calórica de C. fluminea no reservatório de Rosana. Diferenças significativas na densidade calórica de C. fluminea foram observadas ao longo do ano e nas três estações do reservatório. A variação na densidade calórica de C. fluminea, durante o ano, provavelmente foi relacionada à atividade reprodutiva, que exige uma maior alocação de energia em determinado período. O recurso alimentar utilizado por esta espécie pode ser um importante fator na variação temporal e espacial do valor calórico de C. fluminea no reservatório de Rosana.

  7. Fine structure and immunocytochemistry of a new chemosensory system in the Chiton larva (Mollusca: Polyplacophora)

    DEFF Research Database (Denmark)

    Haszprunar, Gerhard; Friedrich, Stefan; Wanninger, Andreas

    2002-01-01

    symmetrically situated pairs lying dorsolaterally and ventrolaterally in the pretrochal part of the trochophore-like larva and they send axons into the cerebral commissure. They are lost at metamorphosis. The fine structure of these cells strongly resembles that of so-called "ampullary cells" known from various...

  8. Geochemical and Crystallographic Study of Turbo Torquatus (Mollusca: Gastropoda) From Southwestern Australia

    Science.gov (United States)

    Roger, L. M.; George, A. D.; Shaw, J.; Hart, R. D.; Roberts, M. P.; Becker, T.; Evans, N. J.; McDonald, B. J.

    2018-01-01

    Shells of the marine gastropod Turbo torquatus were sampled from three different locations along the Western Australian coastline, namely Marmion Lagoon (31°S), Rottnest Island (32°S), and Hamelin Bay (34°S). Marmion Lagoon and Rottnest Island have similar sea surface temperature ranges that are ˜1°C warmer than Hamelin Bay, with all sites influenced by the warm southward flowing Leeuwin Current. The shells were characterized using crystallographic, spectroscopic, and geochemical analyses. Shell mineral composition varies between the three sites suggesting the influence of sea surface temperature, oxygen consumption, and/or bedrock composition on shell mineralogy and preferential incorporation and/or elemental discrimination of Mg, P, and S. Furthermore, T. torquatus was found to exert control over the incorporation of most, if not all, the elements measured here, suggesting strong biological regulation. At all levels of testing, the concentrations of Li varied significantly, which indicates that this trace element may not be a suitable environmental proxy. Variation in Sr concentration between sites and between specimens reflects combined environmental and biological controls suggesting that Sr/Ca ratios in T. torquatus cannot be used to estimate sea surface temperature without experimentally accounting for metabolic and growth effects. The mineral composition and microstructure of T. torquatus shells may help identify sea surface temperature variations on geological time scales. These findings support the previously hypothesized involvement of an active selective pathway across the calcifying mantle of T. torquatus for most, if not all, the elements measured here.

  9. An annotated list of the species of the genus Corbicula from Indonesia (Mollusca: Corbiculidae)

    NARCIS (Netherlands)

    Djajasasmita, Machfudz

    1977-01-01

    The species of the genus Corbicula known from Indonesia are alphabetically listed and noted. Sixteen out of the 35 described species are considered valid, i.e. C. gustaviana, C. moltkiana, C. sumatrana, C. tobae and C. tumida from Sumatra; C. javanica, C. pulchella and C. rivalis from Java; C.

  10. Wood-Boring Bivalves (Mollusca: Teredinidae, Pholadidae) of Pacific coast of Colombia

    International Nuclear Information System (INIS)

    Cantera K, Jaime R

    2010-01-01

    Twelve species of wood-boring bivalves, ten of the family Teredinidae and two of family Pholadidae were collected in mangroves at 6 locations of the Pacific coast of Colombia. This paper presents a brief escription of these species, including size, ecological notes and geographical distribution.

  11. On the morphology of Laevapex vazi n. sp. from Brazil (Mollusca: Pulmonata: Basommatophora: Ancylidae

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    Sonia Barbosa dos Santos

    1989-01-01

    Full Text Available A description of Laevapex vazi n. sp. based on 8 specimens collectec in Ourinhos, state of São Paulo, is presented. Shell thin, diaphanous, with a light brown periostracum and moderately elliptical opening. Apex not pointed, smooth, situated on the right posterior region of the shell, inclined to the right often reaching the edge of the shell or extending beyond it. Concentric lines clearly visible; radial striation not visible or when perceptible very thin, here and there. Ratios: shell width/shell lenght = 0,60 - 0,67 (mean = 0,63; shell height/shell length = 0,50 - 0,61 (mean = 0,55; shell height/shell width = 0,33 - 0,40 (mean = 0,35. Body of normal ancylid type; mantle pigmentation concentrated on the left side; three muscles are seen: a round posterior one on the left side, an elliptical muscle on the right anterior side and an almost almond-shaped one on the left anterior side. Tentacles with a medium core of black pigment. Pseudobranch two-lobed and folded, the dorsal lobe smaller than the vetral one. Ovotestis with 20 unbranched diverticula, around a short collecting canal. Ovispermiduct with an enlargement with several round outpocketings constituting the seminal vesicle. Carrefour as a round sac. Albumen gland almost cylindrical with several acinous diverticula. Elongated nidamental gland continous with the galndular wall of the uterus; uterus flattened and thin-walled. Spermathecal body almost rounded. Pear-shaped prostate without diverticula. Penial complex without flagellum but with well-developed ultra-penis and penis. Jaw horseshoe shaped. Radular forma 20.1.20; raquidian tooth quadricuspid, asymmetrical. The genus Laevapex Walker, 1903 is recorded for the first time in Brazil. It is easily distinguished from South American Gundlachia Pfeiffer, 1849 by its penial complex. Laevapex vazi is dedicated to Dr. Jorge Faria Vaz, from SUCEN-SP, who have been sent to me the specimens.

  12. Keelan, käsen, poon ja lasen või osutan abi? [1.-2. osa] / Kärt Muller

    Index Scriptorium Estoniae

    Muller, Kärt

    2007-01-01

    Kaalutlusõiguse sisust ja põhimõtetest hoolekande teostamisel väljamõeldud kaasuste näitel, põhjendamiskohustuse sisust ja vajalikkusest. Võrdsest kohtlemisest kaalutlusõiguses, kaalutlusvigade kataloogist ja kaalutlusõiguse teostamisest praktikas Riigikohtu lahendite näite

  13. Morphofunctional evaluation of the testicle and the spermatogenic process of adult white-eyed parakeets (Aratinga leucophthalma MULLER, 1776) during the different seasons of the year.

    Science.gov (United States)

    Peixoto, J V; Paula, T A R; Balarini, M K; Matta, S L P; Santos, J A D; Lima, C B; Peixoto, G V

    2012-08-01

    In this experiment, testicle fragments of 14 adult White-eyed Parakeets (Aratinga leucophthalma) were evaluated as for their seasonal reproductive activities using the following quantitative parameters: average thickness of the testicular tunica albuginea, volumetric proportion of tubular and extratubular compartments, average diameter of the seminiferous tubules and corporal weight. Parameters were created for qualitative evaluations of the degree of spermatogenic development. In this experiment, all the animals were distributed into four groups, and their testicular fragments were collected during the middle of summer, fall, winter and spring. The animals were submitted to volatile general anaesthesia, and a biopsy was made by celioscopy. The fragments collected were processed histologically. The slides were prepared and later evaluated by using an optical microscope. The average seasonal values of the corporal weight increased, starting in the winter and reaching the peak during the spring. A seasonal testicle cycle was observed, because, in the spring, the testicles showed values for the quantitative and qualitative parameters of spermatic production compatible with the period of greater activity, while the opposite thing happened during the fall. Our data indicate that the parameters of sperm production may be correlated with daily light rather than with air humidity. © 2012 Blackwell Verlag GmbH.

  14. Melanoides tuberculata (Mollusca: Thiaridae as an intermediate host of Centrocestus formosanus (Trematoda: Heterophyidae in Brazil Melanoides tuberculata (Mollusca: Thiaridae como hospedeiro intermediário de Centrocestus formosanus (Trematoda: Heterophyidae no Brasil

    Directory of Open Access Journals (Sweden)

    Hudson Alves Pinto

    2010-08-01

    Full Text Available Pleurolophocercous cercariae emerged from naturally infected Melanoides tuberculata from Minas Gerais State, Brazil, were used to perform experimental infection of laboratory-reared Poecilia reticulata. Mature metacercariae were obtained from the gills of fishes and force-fed to Mus musculus. The adult parasites which recovered from small intestines of mice were identified as Centrocestus formosanus. This is the first report of M. tuberculata as intermediate host of this heterophyid in Brazil.Cercárias do tipo pleurolofocerca emergidas de Melanoides tuberculata naturalmente infectados coletados na represa da Pampulha, Belo Horizonte, Minas Gerais, Brasil, foram utilizadas para a infecção experimental de Poecilia reticulata criados em laboratório. Metacercárias maduras foram obtidas nas brânquias dos peixes e administradas por via oral a Mus musculus. Parasitos adultos recuperados no intestino delgado dos camundongos foram identificados como Centrocestus formosanus. Este é o primeiro relato de M. tuberculata como hospedeiro intermediário deste parasito no Brasil.

  15. Desarrollo morfológico e histológico del sistema reproductor de Pomacea patula catemacensis (Baker 1922 (Mollusca, Caenogastropoda: Ampullariidae Morphological and histological development of the reproductive system of Pomacea patula catemacensis (Baker 1922 (Mollusca, Caenogastropoda: Ampullariidae

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    AURA CARREÓN-PALAU

    2003-12-01

    Full Text Available El "tegogolo" Pomacea patula catemacensis es un gasterópodo dulceacuícola comestible, endémico del Lago de Catemaco en Veracruz, México. En los últimos años las poblaciones naturales se han visto diezmadas debido a que su captura se realiza sin control, a lo que se suma el alto grado de deterioro ambiental que presenta el lago, producto del "azolvamiento", así como por la contaminación por plaguicidas y detergentes. El objetivo del presente estudio fue caracterizar histológica y morfológicamente el sistema reproductor de P. patula catemacensis y determinar las etapas de madurez gonádica en condiciones de laboratorio. Se determinó que la maduración depende de la talla y no de la edad de los organismos, y se identificaron cuatro etapas principales en el desarrollo de machos y hembras: Los estadios y sus longitudes promedio ± intervalo de confianza del 95 % son (1 inmadura o indiferenciada (talla de 0,72 a 7 mm, (2 maduración temprana (18,95 ± 1,96 mm, (3 maduración intermedia (29,29 ± 4,9 mm y (4 madurez total (35,89 ± 3,92 mm. En este molusco los sexos están separados, la fertilización es interna y el desarrollo es ovovivíparo. En las hembras la secreción de albúmina y de carbonato de calcio se realiza en la glándula de la albúmina, característica en la que difiere de otras especies como P. paludosa y P. canaliculata, las cuales poseen además glándula de la cápsula. Es posible identificar el grado de madurez de los caracoles utilizando criterios anatómicos visuales, como la glándula de la albúmina, en el caso de la hembra, y el órgano copulador en el machoThe "apple snail" Pomacea patula catemacensis is an edible freshwater mollusc, endemic to the Catemaco Lake in Veracruz, Mexico. During the past few years, the natural populations of this species have been depleted mainly by uncontrolled fishery, and because of environmental degradation and pollution by pesticides and detergents. In the present study, we carried out the histological and morphological characterization of the reproductive system of P. patula catemacensis under laboratory conditions. We found that the reproductive development of this snail depended more on the size than on the age the animals, and identified four development main stages, both for males and females. The main stages and their mean lengths ± confidence interval at P < 0.05 were (1 immature or not differenced (from 0.72 to 7 mm, (2 early maturation (from 18.95 ± 1.96 mm, (3 intermediate maturation (from 29.29 ± 4.9 mm, and (4 full maturity (from 35.89 ± 3.92 mm. This species is ovoviviparous, both sexes are separated, and fertilization is internal. Albumin and calcium carbonate secretion in females are performed through the albumin gland, a trait that distinguishes this species from others, such as P. paludosa and P. canaliculata. The stage of development can be identified by means of using anatomical traits, such as the albumin gland (in the case of females, or the intromittent organ (in males

  16. Os gêneros Fasciolaria Lamarck, 1799 e Leucozonia Gray, 1847 no nordeste brasileiro (Mollusca: Gastropoda: Fasciolariidae The genera Fasciolaria Lamarck, 1799 and Leucozonia Gray, 1847 in the northeastern Brazil (Mollusca: Gastropoda: Fasciolariidae

    Directory of Open Access Journals (Sweden)

    Helena Matthews-Cascon

    1989-01-01

    Full Text Available The genera Fasciolaria Lamarck, 1799 and Leucozonia Gray, 1847 are represented in Northeastern Brazil by three species. Fasciolaria aurantiaca Lamarck, 1816; Leucozonia ocellata (Gmelin, 1791 and Leucozonia nassa (Gmelin, 1791. The three species are described and illustrated. An identification key for all the above mentioned taxa is included, together with some ecological data. The anatomy and radula of Fasciolaria aurantiaca and Leucozonia nassa are described and illustrated. Polimorfism in Fasciolaria aurantiaca and Leucozonia nassa is discussed.

  17. Algumas observações de campo sobre biologia e ecologia de Pomacea haustrum (Reeve, 1856 (Mollusca, Pilidae Some field observation on biology and ecology of Pomacea haustrum (Reeve, 1856 (Mollusca, Pilidae

    Directory of Open Access Journals (Sweden)

    Carlos Tito Guimarães

    1981-12-01

    Full Text Available Algumas observações de campo sobre o pilídeo Pomacea haustrum (Reeve, 1856, predador-competidor de planorbíneos hospedeiros intermediários da esquistossomose mansoni mostraram que: Cópula e oviposição são realizadas, preferencialmente, à noite e de madrugada. As desovas - cujas dimensões e formas dependem do número de ovos e tipos dos suportes - sao ovipostas, na maioria das vezes, de 6 a 10 cm acima do nível da água eclodindo após 9 a 30 dias de incubação; o número médio de ovos por desova foi de 236. A alimentação habitual deste molusco consiste de algas confervóides, além de vegetais aquáticos natantes e submersos; entretanto, e comum a utilização de outros materiais como alimento.Tem como habitat a zona marginal mais rasa das coleções hídricas onde e encontrado, predominando, aparentemente, nos ambientes lênticos. A distribuição espacial esta condicionada por determinadas características dos biótopos. Algumas aves aquáticas - anatídeos, ralídeos, etc.- revelaram-se importantes inimigos naturais, atacando além das desovas exemplares jovens e adultos; em determinadas condições podem constituir fator impeditivo da implantação e colonização de novos biótopos.Some field observations on the pilid Pomacea haustrum (Reeve, 1856, predator-competitor of schistosomiasis mansoni planorbid intermediate hosts have shown that: Copula and oviposition are preferably carried out at night or at dawn. Eggmasses - whose dimension and shape depend on the number of eggs and types of supports - are often laid from 6 to 10 com above the water level and hatched 9 to 30 days after incubation; the average number of eggs/egg-mass was 236. Habitual food consist of confervoid algae, besides natant and submerged aquatic vegetation; it is common, however, the utilization of the other material as food. Its habitat is the shallower marginal zone of hidric collections, predominatly in lentic surrounding. Its spacial distribution is conditioned to the biotipe special characteristics. Some aquatic birds - anatid, ralid, etc. - reveal important natural enemies, attacking both young and adult specimens, besides the egg-masses; under certain conditions they may be an impedictive factor to the establishment and colonization of this pilid in new biotopes.

  18. A new species of Temnocephala (Platyhelminthes, Temnocephalida commensal of Pomella megastoma (Mollusca, Ampullariidae from Misiones, Argentina Una especie nueva de Temnocephala (Platyhelminthes, Temnocephalida comensal de Pomella megastoma (Mollusca, Ampullariidae de Misiones, Argentina

    Directory of Open Access Journals (Sweden)

    Cristina Damborenea

    2008-08-01

    Full Text Available Temnocephala lamothei n. sp., a commensal of Pomella megastoma (Sowerby, 1825, is described herein from specimens collected at Arroyo Yabotí-Miní (Misiones province, Argentina. Juveniles and adults were removed from the mantle cavity by host relaxation. Distinctive characters of the new species are: non-partitioned intestine; conical cirrus with 1 face flat and another concave; distal area with spines, as evidenced by a strong, oblique sclerotized ring, and 2 rows of long spines, an internal one with long spines arising from base of introvert and an external one arising from distal end of the introvert. The closest species are T. iheringi, T. rochensis and T. haswelli, which are also commensals of mollusc species. The presence of this new species of Temnocephala, and its similarity to the other species that are commensals of molluscan species, suggest the existence of a morphologically homogeneous group.Temnocephala lamothei n. sp., comensal de Pomella megastoma (Sowerby, 1825, se describe para el arroyo Yabotí-Miní, provincia de Misiones, Argentina. Se extrajeron ejemplares juveniles y adultos de la cavidad paleal, por relajación de los hospederos. Las características distintivas de la nueva especie son: intestino no septado, cirro de forma cónica, con una cara plana y otra cóncava, zona distal con espinas evidente por un fuerte anillo oblicuo esclerosado. Dos hileras de espinas se reconocen en el extremo distal, 1 interna de espinas largas, que surge desde la base del introverso, y 1 externa, que surge del extremo distal del mismo. Las especies más semejantes son T. iheringi, T. rochensis y T. haswelli, especies comensales de moluscos con las que es comparada. El hallazgo de esta nueva especie de Temnocephala y sus características semejantes a las restantes especies del género comensales de moluscos, sugieren que las especies conocidas hasta la fecha formen un grupo morfológicamente homogéneo.

  19. Registro de Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda no Brasil: caramujo hospedeiro intermediário da angiostrongilíase Occurrence of Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda in Brazil: intermediate snail host of angiostrongyliasis

    Directory of Open Access Journals (Sweden)

    Horácio Manuel Santana Teles

    1997-06-01

    Full Text Available A introdução de Achatina fulica é assinalada em Itariri, SP, Brasil. Essa espécie de caramujo terrestre foi importada para cultivo, visando à comercialização para consumo humano como "escargot". O encontro de exemplares em vida livre mostra a dispersão de A. fulica e, conseqüentemente, o risco de transmissão de Angiostrongylus cantonensis, nematóide parasita do homem e de outros vertebrados. Além disso, o caramujo é uma praga importante da agricultura.Achatina fulica, the intermediate snail host of angiostrongyliasis and also an agricultural pest, is being bred in Brazil for human consumption as "escargot". The snail has escaped from its artificial breeding sites and its dispersal in Itariri county, State of S. Paulo, is reported here for the first time. A. fulica is a transmitter of the rat lungworm Angiostrongylus cantonensis, nematode which causes meningoencephalic angiostrongyliasis; the risks of human contamination are commented on.

  20. Desarrollo morfológico e histológico del sistema reproductor de Pomacea patula catemacensis (Baker 1922) (Mollusca, Caenogastropoda: Ampullariidae) Morphological and histological development of the reproductive system of Pomacea patula catemacensis (Baker 1922) (Mollusca, Caenogastropoda: Ampullariidae)

    OpenAIRE

    AURA CARREÓN-PALAU; ESTHER URIA-GALICIA; FÉLIX ESPINOSA-CHÁVEZ; FERNANDO MARTÍNEZ-JERÓNIMO

    2003-01-01

    El "tegogolo" Pomacea patula catemacensis es un gasterópodo dulceacuícola comestible, endémico del Lago de Catemaco en Veracruz, México. En los últimos años las poblaciones naturales se han visto diezmadas debido a que su captura se realiza sin control, a lo que se suma el alto grado de deterioro ambiental que presenta el lago, producto del "azolvamiento", así como por la contaminación por plaguicidas y detergentes. El objetivo del presente estudio fue caracterizar histológica y morfológicame...

  1. Spermatozoan ultrastructure in the trigonioid bivalve Neotrigonia margaritacea Lamarck (Mollusca): Comparison with other bivalves, especially Trigonioida and Unionoida

    Science.gov (United States)

    Healy, J. M.

    1996-06-01

    Spermatozoa of the trigonioid bivalve Neotrigonia margaritacea (Lamarck) (Trigoniidae, Trigonioida) are examined ultrastructurally. A cluster of discoidal, proacrosomal vesicles (between 9 to 15 in number) constitutes the acrosomal complex at the nuclear apex. The nucleus is short (2.4 2.6 μm long, maximum diameter 2.2 μm), blunt-conical in shape, and exhibits irregular lacunae within its contents. Five or sometimes four round mitochondria are impressed into shallow depressions in the base of the nucleus as is a discrete centriolar fossa. The mitochondria surround two orthogonally arranged centrioles to form, collectively, the midpiece region. The distal centriole, anchored by nine satellite fibres to the plasma membrane, acts as a basal body to the sperm flagellum. The presence of numerous proacrosomal vesicles instead of a single, conical acrosomal vesicle sets Neotrigonia (and the Trigonioida) apart from other bivalves, with the exception of the Unionoida which are also known to exhibit this multivesicular condition. Spermatozoa of N. margaritacea are very similar to those of the related species Neotrigonia bednalli (Verco) with the exception that the proacrosomal vesicles of N. margaritacea are noticeably larger than those of N. bednalli.

  2. Opisthobranchs from the western Indian Ocean, with descriptions of two new species and ten new records (Mollusca, Gastropoda

    Directory of Open Access Journals (Sweden)

    Nathalie Yonow

    2012-05-01

    Full Text Available Seventy species of opisthobranchs are described in this work based on collections from the Persian Gulf, Socotra, Kenya, Zanzibar, Madagascar, La Réunion, Mauritius, the Seychelles, the Maldives, and Sri Lanka. Ten species are newly recorded from the western Indian Ocean and four species are recorded in the scientific literature for the first time since their original descriptions. Two species are described as new: Cyerce bourbonica sp. n. from La Réand Doriopsilla nigrocera sp. n. from the Persian Gulf coast of Saudi Arabia. Chromodoris cavae is removed from its synonymy with C. tennentana and redescribed from specimens from La Réunion, while several new synonyms are proposed for some commonly occurring species. Risbecia bullockii is recorded for the second time from the Indian Ocean and assigned to its correct genus.

  3. Seasonal variations in metal content of two Unio pictorum mancus (Mollusca, Unionidae populations from two lakes of different trophic state

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    Pier Renato TRINCHERINI

    2007-02-01

    Full Text Available To assess the impact of lake trophy on trace element accumulation by Unio pictorum mancus, a population from the mesooligotrophic Lake Maggiore was compared with a population from the eutrophic Lake Candia. The element content in soft tissue and shell biomass, the seasonal variations of element concentrations in soft tissues and shell, and the relationship between element concentrations in the water and those in the tissues were estimated in pursuit of this objective. Thirteen mussel samplings were performed in Lake Maggiore between May 2003 and September 2004 and in Lake Candia between June 2003 and August 2004. Filtered water samples were collected seasonally. Water, shell and soft tissue samples were analysed by ICP-OES and ICP-MS for the measurement of following elements: Zn, Cu, Fe, Mn, Ni, As, Pb, Co, Cr, Mo, V, Cd, Be and Ca. The element concentrations in the mussel tissues and shell from Lake Maggiore were higher than those from Lake Candia. Due to the higher population density and higher element concentrations in the mussels of Lake Maggiore, the element content in the biomass per m2 in this lake far exceeded that in Lake Candia. The element concentrations in the mussel tissues, but not in their shells, of both lakes showed a seasonal pattern of variation; this was to be expected as a result of the slower turnover time of the elements in the shell than in the tissues. For all the elements, except Mo, Cr and Be, the "concentration factor" (C.F. value was higher in Lake Maggiore than in Lake Candia mussels, ranging from 10 to 104 and 10 to 103 respectively. The higher concentrations in the mussel tissues from Lake Maggiore were justified not merely by the higher element concentrations in the lake water, but probably also because other causes, such as element concentrations in food and element abundance in available forms, combine to affect the concentrations of the elements in the tissues.

  4. The effects of mercury exposure on the surface morphology of gill filaments in Perna perna (Mollusca: Bivalvia)

    CSIR Research Space (South Africa)

    Gregory, MA

    1999-01-01

    Full Text Available each animal were analysed for mercury using an atomic absorption spectrometer. Mercury concentration increased from 0.13 (pre-immersion) to 87 mu g/g after day 24. Surface morphology remained normal for all animals in tank 2 and for those exposed to Hg...

  5. Detection and genetic distance of resistant populations of Pseudosuccinea columella (Mollusca: Lymnaeidae) to Fasciola hepatica (Trematoda: Digenea) using RAPD markers.

    Science.gov (United States)

    Calienes, Aymé Fernandez; Fraga, Jorge; Pointier, Jean-Pierre; Yong, Mary; Sanchez, Jorge; Coustau, Christine; Gutiérrez, Alfredo; Théron, André

    2004-09-01

    Twelve natural populations of Pseudosuccinea columella snails, sampled in the western and central regions of Cuba, were analyzed using the RAPD-PCR technique to screen for resistance to Fasciola hepatica. Ten OPA primers previously shown to produce marker bands for resistance and susceptibility were tested. A new population of P. columella (El Azufre, Pinar del Río) exhibited the amplification patterns of resistant snails, and its resistant status was confirmed after experimental exposure to miracidia. No genetic variability was detected across or within the susceptible isolates. Similarly, the novel resistant isolate displayed an RAPD profile identical to the profile of two other isolates previously identified as resistant to F. hepatica. However, clear differences in RAPD banding patterns and genetic distance were observed between resistant and susceptible isolates.

  6. Marine Mollusca of isotope stages of the last 2 million years in New Zealand. Part 3, Gastropoda (Vetigastropoda - Littorinimorpha)

    International Nuclear Information System (INIS)

    Beu, A.G.

    2010-01-01

    Three new species: Grandicrepidula hemispherica (Nukumaruan, S Hawke's Bay), Pelicaria Granttaylori (Mangapanian-early Nukumaruan, Wanganui-Hawke's Bay), Pelicaria arahura (Waipipian-early Mangapanian, Westland and Hawke's Bay). Drawings of marine species in Smith's (1874) three plates of New Zealand molluscan types are republished. Further Australian molluscs in Wanganui Basin: Sabia australis (Lamarck), Clanculus plebejus (Philippi), both early Nukumaruan. Further northern New Zealand molluscs in Wanganui Basin: Stephopoma roseum (Quoy and Gaimard), OIS 13, 9. Distinctive gastropods extinct at end Nukumaruan: Struthiolaria frazeri (Hutton), Taxonia suteri (Marwick). Taniella planisuturalis (Marwick) (Opoitian-Nukumaruan, southern NZ) and Trivia (Ellatrivia) zealandica (Kirk) (Nukumaruan, Hawke's Bay-Wanganui; Castlecliffian, North Canterbury) occur in Castlecliffian (OIS 15?) rocks at Whakatane. Cantharidella tessellate (A. Adams) and Risellopsis varia (Hutton), formerly Haweran, are recorded from Nukumaruan and Castlecliffian rocks, respectively. New fossil late Nukumaruan-early Castlecliffian records listed from Mikonui-1 offshore well, Westland, include Malluvium calcareum (Suter) and 10 other species. Other biostratigraphically useful gastropods: Calliostoma (Maurea) nukumaruense (Laws) (Mangapanian-OIS 17); Argobuccinum pustulosum (Lightfoot), Semicassis labiate (Perry) (both earliest in OIS 7). New synonymy: Zeacumantus perplexus (Marshall and Murdoch) =Z. lutulentus (Kiener); Pelicaria vermis (Martyn) =all named Nukumaruan-Recent forms (other than P. rugosa (Marwick) and P. granttaylori n. sp.); Trivia flora Marwick =T.zealandica Kirk. Taxonomy revised: Zelippistes benhami (Suter) (OIS 13 and 9 at Wanganui), distinguished from Lippistes and Separatista; Stiracolpus species, informally; Maoricrypta profunda (Hutton), Waipipian-early Castlecliffian (- OIS 19); M. radiata (Hutton) (=incurva Zittel,=hochetteriana Woods, =wilckensi Finlay), (Middle Miocene?) Tongaporutuan-Opoitian; Eunaticina cincta (Hutton), holotype illustrated. (author). 427 refs., 22 figs.

  7. Genetics and shell morphometrics of assimineids (Mollusca, Caenogastropoda, Truncatelloidea in the St Lucia Estuary, South Africa

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    Nelson Miranda

    2014-06-01

    Full Text Available The Assimineidae are a family of amphibious microgastropods that can be mostly found in estuaries and mangroves in South Africa. These snails often occur in great numbers and are ecologically important to the St Lucia Estuary, which forms a crucial part of the iSimangaliso Wetland Park, a UNESCO World Heritage Site. Genetic and shell morphometric analyses were conducted on individuals collected from nine localities distributed from the northern lake regions to the southern lake and the mouth of the St Lucia estuarine lake. Mitochondrial (COI and nuclear (28S DNA was used to construct Bayesian Inference, Neighbour-joining, Maximum Parsimony and Maximum Likelihood trees. Principal Component Analysis and Cluster Analysis were performed on standard shell parameter data. Results indicate that two different taxa are present in St Lucia. The taxon comprising individuals from the South Lake and St Lucia Estuary Mouth is identified as Assiminea cf. capensis Bartsch, in accordance with the latest taxonomic consensus. The taxon comprising assimineid individuals from False Bay, North Lake and South Lake, is here tentatively named “A.” aff. capensis (Sowerby. These two taxa exhibit patterns of spatial overlap that appear to vary depending on environmental parameters, particularly salinity. The need to resolve the complex taxonomy of assimineids is highlighted.

  8. Seasonal variation in the abundance and distribution of Anomalocardia flexuosa (Mollusca, Bivalvia, Veneridae in an estuarine intertidal plain

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    Jacqueline S. Silva-Cavalcanti

    2018-02-01

    Full Text Available Spatial and temporal density and biomass of the infaunal mollusk Anomalocardia flexuosa (Linnaeus, 1767 evaluated a tidal plain at Goiana estuary (Northeast Brazil. Three hundred and sixty core samples were taken during an annual cycle from three intertidal habitats (A, B and C. Shell ranged from 2.20 to 28.48 mm (15.08 ± 4.08 mm. Recruitment occurred more intensely from January to March. Total (0–1,129 g m−2 differed seasons (rainy and dry, with highest values in the early rainy season (221.0 ± 231.44 g m−2; and lowest values in the late dry season (57.34 ± 97 g m−2. The lowest occurred during the late rainy (319 ± 259 ind m−2 and early dry (496 ± 607 ind m−2 seasons. Extreme environmental situations (e.g., river flow, salinity and water temperature at the end of each season also affected density ranges (late dry: 0–5,798 ind m−2; late rainy: 0–1,170 ind m−2. A. flexuosa in the Goiana estuary presented a dominance of juvenile individuals (shell length < 20 mm, with high biomass main the recruitment period. Average shell length, density and biomass values suggest overfishing of the stock unit. A. flexuosa is an important food and income resource along its whole distribution range. The species was previously also known as Anomalocardia brasiliana (Gmelin, 1791.

  9. Myogenesis in Aplysia californica (Cooper, 1863) (Mollusca, Gastropoda, Opisthobranchia) with special focus on muscular remodeling during metamorphosis

    DEFF Research Database (Denmark)

    Wollesen, Tim; Wanninger, Andreas; Klussmann-Kolb, Annette

    2008-01-01

    To date only few comparative approaches tried to reconstruct the ontogeny of the musculature in invertebrates. This may be due to the difficulties involved in reconstructing three dimensionally arranged muscle systems by means of classical histological techniques combined with light or transmissi...

  10. Detection of Bioactive Compounds in the Mucus Nets of Dendropoma maxima, Sowerby 1825 (Prosobranch Gastropod Vermetidae, Mollusca

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    Anne Klöppel

    2013-01-01

    Full Text Available The sessile suspension-feeding wormsnail Dendropoma maxima, Sowerby 1825 (Vermetidae secretes a mucus net to capture planktonic prey. The nets are spread out over the corals and often have remarkable deleterious effects on them like changes in growth form and pigmentation shifts not uncommonly resulting in tissue necrosis. Until now, there is no explanation for this phenomenon although the indication as well as theories about its genesis is mentioned in several publications. Vermetids are well studied concerning the intraspecific competition with neighboring individuals but not in their interaction with other taxa like corals or fish. We did extensive in situ video recording and observed that fish avoided the plankton-load nets although several specialized taxa are known to be molluscivores, mucivores, and/or feed on plankton. As many molluscs use chemical weapons to combat feeding pressure and to defend themselves against predators, we screened empty and plankton-load mucus nets for potential bioactive metabolites. Bioactivity testing was performed with a recently developed system based on a chromatographic separation (high-performance thin-layer chromatography (HPTLC and a bioassay with luminescent bacteria Vibrio fischeri. Thus, we found at least two active compounds exclusively accumulated by the wormsnails themselves. This is the first record of bioactive properties in the whole family of Vermetidae.

  11. Effect of zinc and benzene on respiration and excretion of mussel larvae (Perna perna (Linnaeus, 1758 (Mollusca; Bivalvia

    Directory of Open Access Journals (Sweden)

    RADLVC. Jorge

    Full Text Available The presence of pollutants in the ocean may affect different physiological parameters of animals. Oxygen consumption and ammonia excretion were evaluated in D-shaped larvae of mussels (Perna perna exposed to zinc sulphate (ZnSO4 and benzene (C6H6. When compared to the control group, both pollutants presented a significant reduction in oxygen consumption. A reduction in the ammonia excretion was also observed, both for ZnSO4 and C6H6 and also in the oxygen consumption. The results indicate that anaerobic metabolism may occur at the beginning of P. perna mussels development, as observed in veliger larvae. The O:N ratio under experimental conditions showed low values indicating that catabolism in veliger larvae was predominantly proteic.

  12. Metal concentrations in Unio pictorum mancus (Mollusca, Lamellibranchia from of 12 Northern Italian lakes in relation to their trophic level

    Directory of Open Access Journals (Sweden)

    Paolo LODIGIANI

    2003-08-01

    Full Text Available This research aims to test the reliability of environmental monitoring by bioaccumulators of pollutants; that is to establish a positive relationship between the pollutant concentrations in the bioaccumulator and those in the water in which it lives. To this end we analysed the contents of Al, Cu, Zn, Fe, Mn and Ca in the soft tissues and shell of Unio pictorum mancus. The filtered water samples from the mussel habitat were analysed for the same metals. The mussels were collected from 15 stations settled in 12 Northern Italian lakes during the first two weeks of July 2001. These results were obtained: a metal concentrations varied widely with mussel size and among stations; b a significant positive correlation between the concentration of calcium in the water and in the mussel tissues, but no relationship emerged for the other metals; c no relationship between the metal concentrations in the tissues and those in the shell was found; d there was a certain tendency for Mn, Fe and Zn concentrations in the soft tissues to increase with shell size; e the sequence of the decreasing metal concentrations arranged for the tissues was similar to that of the shell, but rather different from that in the water; and f the concentration factor values of the trace metals were high for the shell and soft tissues. In highly productive lakes large size mussels dominated, whereas small mussels were more abundant in low productive lakes. Although the metal concentrations in the water of productive lakes were greater than in low productive ones, the metal concentrations in the tissues of the mussels from the latter were generally higher than those in the mussels from the former. We propose some hypotheses to explain this paradox. Finally, our results show that the metal concentrations in the mussels do not reflect the metal concentrations in the water in which they live. It follows that this commonly used but oversimplified monitoring system cannot be recommended. On the other hand mussels may be very useful for other purposes, such as identifying new pollutants or pollutants present in such low concentrations that they cannot be measured with the commonly used methods. The pollutant content of mussels may enable the variations in time of the pollutant level of an environment to be monitored. In addition, the transplantation of mussels from a clean site to a polluted one may be a useful tool for identify the pollutants of the receiving environment.

  13. Isolation and Characterization of the First Microsatellite Markers for the Endangered Relict Mussel Hypanis colorata (Mollusca: Bivalvia: Cardiidae

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    Luis Ovidiu Popa

    2011-01-01

    Full Text Available Hypanis colorata (Eichwald, 1829 (Cardiidae: Lymnocardiinae is a bivalve relict species with a Ponto-Caspian distribution and is under strict protection in Romania, according to national regulations. While the species is depressed in the western Black Sea lagoons from Romania and Ukraine, it is also a successful invader in the middle Dniepr and Volga regions. Establishing a conservation strategy for this species or studying its invasion process requires knowledge about the genetic structure of the species populations. We have isolated and characterized nine polymorphic microsatellite markers in H. colorata. The number of alleles per locus ranged from 4 to 28 and the observed heterozygosity ranged from 0.613 to 1.000. The microsatellites developed in the present study are highly polymorphic and they should be useful for the assessment of genetic variation within this species.

  14. Abyssal Solenogastres (Mollusca, Aplacophora from the Northwest Pacific: Scratching the Surface of Deep-Sea Diversity Using Integrative Taxonomy

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    Franziska S. Bergmeier

    2017-12-01

    Full Text Available Solenogastres (Aplacophora is a small clade of marine, shell-less worm-molluscs with close to 300 valid species. Their distribution ranges across all oceans, and whereas the vast majority of species has been collected and described from the continental shelf and slope, only few species are known from depths below 4,000 m. Following traditional taxonomy, identification of specimens to species level is complex and time-consuming and requires detailed investigations of morphology and anatomy—often resulting in the exclusion of the clade in biodiversity or biogeographic studies. During the KuramBio expedition (Kuril-Kamchatka Biodiversity Studies to the abyssal plain of the Northwest Pacific and the Kuril-Kamchatka Trench, 33 solenogaster specimens were sampled from 4,830 m to 5,397 m. Within this study we present an efficient workflow to address solenogaster diversity, even when confronted with a high degree of singletons and minute body sizes, hampering the use of single individuals for multiple morphological and molecular approaches. We combine analyses of external characters and scleritome with molecular barcoding based on a self-designed solenogaster specific set of mitochondrial primers. Overall we were able to delineate at least 19 solenogaster lineages and identify 15 species to family level and beyond. Based on our approach we identified three key lineages from the two regionally most species-rich families (Acanthomeniidae and Pruvotinidae for deeper taxonomic investigations and describe the novel abyssal species Amboherpia abyssokurilensis sp. nov. (Cavibelonia, Acanthomeniidae using microanatomical 3D-reconstructions. Our study more than doubles the previous records of solenogaster species from the Northwest Pacific and its marginal seas. Almost all lineages are reported for the first time from the region of the (Northwest Pacific, vastly expanding distribution ranges of the respective clades. Moreover it doubles the number of Solenogastres collected from abyssal depths on a global scale and underlines the lack of exploratory α-diversity work in the abyssal zone for reliable species estimates in marine biodiversity.

  15. Conservational status and demographic characteristics of Patella ferruginea Gmelin, 1791 (Mollusca, Gastropoda) on the Alboran Island (Western Mediterranean)

    OpenAIRE

    Paracuellos, M.; Nevado, J. C.; Moreno, D.; Giménez, A.; Alesina, J. J.

    2003-01-01

    Due to the high risk of the global extinction in which Patella ferruginea Gmelin, 1791 is found, it is considered of great interest to describe and quantify its demographic characteristics in those sites where it still persists, as well as to evaluate the reasons which have led this limpet to be one of the most threatened marine species in the Mediterranean Sea. Over the study period (2000-2002), systematic census were made on the perimeter of the Alboran Island (Alboran Sea, westernmost area...

  16. Conservational status and demographic characteristics of Patella ferruginea Gmelin, 1791 (Mollusca, Gastropoda on the Alboran Island (Western Mediterranean

    Directory of Open Access Journals (Sweden)

    Paracuellos, M.

    2003-12-01

    Full Text Available Due to the high risk of the global extinction in which Patella ferruginea Gmelin, 1791 is found, it is considered of great interest to describe and quantify its demographic characteristics in those sites where it still persists, as well as to evaluate the reasons which have led this limpet to be one of the most threatened marine species in the Mediterranean Sea. Over the study period (2000-2002, systematic census were made on the perimeter of the Alboran Island (Alboran Sea, westernmost area of the Mediterranean Sea with the object to quantify the abundance of the species in the locality, as well as their external biometry and spatial distribution. As a result, the presence of a probable reproductive population of P. ferruginea was found on the island. The negative effect provoked by the continuous presence of man was proved, prejudicing the population in those zones which were more accessible for their harvesting. For this reason, it is necessary to regulate the use of the natural resources of the island to favour the conservation and spontaneous recolonisation of the zone by P. ferruginea.

  17. Conservational status and demographic characteristics of Patella ferruginea Gmelin, 1791 (Mollusca, Gastropoda) on the Alboran Island (Western Mediterranean)

    OpenAIRE

    Paracuellos, M.; Nevado, J. C.; Moreno, D.; Giménez, A.; Alesina, J. J.

    2003-01-01

    Due to the high risk of the global extinction in which Patella ferruginea Gmelin, 1791 is found, it is considered of great interest to describe and quantify its demographic characteristics in those sites where it still persists, as well as to evaluate the reasons which have led this limpet to be one of the most threatened marine species in the Mediterranean Sea. Over the study period (2000–2002), systematic census were made on the perimeter of the Alboran Island (Alboran Sea, westernmost area...

  18. Recrutamento larval e crescimento de teredinidae (mollusca-bivalvia em região entremarés de manguezais

    Directory of Open Access Journals (Sweden)

    Sônia Godoy Bueno Carvalho Lopes

    1997-01-01

    Full Text Available O recrutamento larval e o crescimento de Teredinidae na região entremarés do manguezal da Praia Dura, Ubatuba, SP, foi acompanhado durante doze meses (08/84 a 08/85 utilizando coletores construídos com madeira de mangue. O tempo decorrido para se detectar a presença dos primeiros Teredinidae foi de aproximadamente sete meses após o início do experimento e o número de indivíduos por coletor foi muito reduzido no período de amostragem. Esses resultados contrastam com os obtidos por outros autores que instalaram coletores em ambiente marinho, mas são semelhantes aos obtidos por autores que instalaram coletores em regiões estuarinas do litoral brasileiro. Essas diferenças nos resultados talvez possam ser explicadas pelo fato da salinidade ser mais baixa e mais variável nos estuários que no ambiente marinho. A análise dos dados sobre o recrutamento larval, permite concluir que a espécie mais abundante foi Nausitora fustieula (Jeffreys, 1860, com principal época de instalação em março e taxa inicial de crescimento de 1,86 mm/day. As outras espécies de Teredinidae, Bankiaflmbriatula Moll & Roch, 1931, Bankia roehi Moll, 1931 e Neoteredo reynei (Bartsch, 1920, apresentaram pequeno número de indivíduos e em função disso, não foi possível determinar suas épocas de instalação e respectivas taxas de crescimento.The larval settlement and growth of Teredinidae in the intertidal region of the Praia Dura mangrove, Ubatuba, SP, were undertaken during one year (08/84 to 08/85 using colectors made from mangrove wood. The presence of the first Teredinidae was detected approximately seven month after the inicial experiment and the number of specimens per coletor was small during the sampling period. These results contrast with those obtained by other authors working in a marine environment, but are similar to those obtained in experiments developed in Brazilian estuaries. The differences between data obtained in marine and estuarine environments, might be explained by the lower and more variable salinity gradient in estuaries. Larval settlement data revealed that the most abundant species was Nausitora fustieula (Jeffreys,1860, which settles on wood prefrerably in March, and has an initial growth rate of 1.86 mm/day. The other Teredinidae species Banida fimbriatula Moll & Roch, 1931, Bankia rochi Moll, 1931 and Neoteredo reynei (Bartsch, 1920, occurred in a very small number of specimens and therefore, their time of settlement and growth rates could not be determined.

  19. Comparative studies on the histology and ultrastructure of the siphons of two species of Tellinidae (Mollusca: Bivalvia from Brazil

    Directory of Open Access Journals (Sweden)

    João E.V.V. Vitonis

    2012-06-01

    Full Text Available Despite the great importance of the siphons for infaunal bivalves, only a few studies have examined their tissues using histology techniques or scanning electron microscopy. In the present study, the siphons of Tellina lineata Turton, 1819 and Macoma biota Arruda & Domaneschi, 2005 were investigated. The siphon walls are composed by a series of muscle sheets of longitudinal ("L", circular ("C" and radial ("R" fibers, with a clear pattern common to both species: there is a main median longitudinal layer (Lm, and two peripheral circular layers, one inner (Ci and one outer (Co, near the epithelia. A median circular layer (Cm separates an internal (Lmi from an outer (Lmo median longitudinal layer. Further, the Co is split by a thin outer longitudinal layer (Lo, forming Coi and Coo layers, the former being obliquely oriented. Thin radial fibers (R delimit clear packages of Lmi and Lmo fibers. In each siphon, there are six longitudinal nerve cords, running within the Lmi layer, adjacent to the Cm. The inhalant and exhalant siphons of M. biota are very similar in structure, but the Lmo of the exhalant siphon is almost twice as thick as its Lmi, while in the inhalant siphon these layers have similar thicknesses; the Coi is very thick, especially in the exhalant siphon. The inhalant siphon of T. lineata is very similar to that of M. biota, differing only with respect to the thickness of the Coi, which in the former species is not as well developed as in the latter. The Lmo of the exhalant siphon of T. lineata is by far the most developed layer, with the Lmi represented only by uniseriate small cells; in the vicinities of the nerve cords, the Cm is split in two layers. The epithelia of both siphons of M. biota and T. lineata bear ciliated receptors, which were difficult to observe as they were frequently covered with mucus. It was possible to observe that cilia are present in both species, differing in length and in the number per receptor between the inhalant and exhalant siphons, and between the species. Detailed comparisons among the siphons of M. biota and T. lineata and other bivalve species are very difficult, because of at least two reasons. First, each investigator has used different methods to prepare and observe the siphons through histological sections; and second, different nomenclatural schemes are used to describe the musculature of the siphons, causing confusion when the same layers are compared among different species. In order to unify the nomenclature of tissue layers of the bivalve siphons, we now propose a scheme to name these layers based on topological homology.

  20. The Japanese oyster drill Ocinebrellus inornatus (Récluz, 1851) (Mollusca, Gastropoda, Muricidae), introduced to the Limfjord, Denmark

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Faasse, Marco; Gittenberger, Adriaan

    2012-01-01

    The predatory neogastropod Ocinebrellus inornatus was first reported from Europe in W France in 1995 and has since been detected at other sites in NW and N France and The Netherlands. It is native to the North Pacific where it preys on the Pacific oyster Crassostrea gigas. Here we report on the o......The predatory neogastropod Ocinebrellus inornatus was first reported from Europe in W France in 1995 and has since been detected at other sites in NW and N France and The Netherlands. It is native to the North Pacific where it preys on the Pacific oyster Crassostrea gigas. Here we report...... on the occurrence of the species in beds of European oysters (Ostrea edulis) in the Limfjord, NW Jutland, Denmark. The morphology-based identification has been confirmed by genetic analysis. The species was probably introduced with oysters imported from France in the 1970s and 1980s. The invasion is still...... relatively localized but as the species has established a reproductive population, it may eventually spread to other parts of the fjord and in time pose a problem to the oyster fishery. The species’ invasion history is reviewed...

  1. In situ distribution and characterization of the organic content of the oyster shell Crassostrea gigas (Mollusca, Bivalvia).

    Science.gov (United States)

    Dauphin, Yannicke; Ball, Alexander D; Castillo-Michel, Hiram; Chevallard, Corinne; Cuif, Jean-Pierre; Farre, Bastien; Pouvreau, Stéphane; Salomé, Murielle

    2013-01-01

    Cultivation of commercial oysters is now facing the possible influence of global change in sea water composition, commonly referred to as "ocean acidification". In order to test the potential consequence of the predicted environmental changes, a cultivation experiment was carried out. The left and right valves of the oyster shell Crassostrea gigas differ in their structure; moreover, lenses of non compact layers are irregular. The shell layers of juvenile C. gigas are studied using a variety of highly spatially resolved techniques to establish their composition and structure. Our results confirm the presence of three different calcitic structural types. The role of the lenses of chalky layers is not yet deciplered. Despite a common mineralogy, the elemental composition of the layers differs. The sulphur aminoacids and sulphated polysaccharide contents of the intracrystalline and intercrystalline matrices differ, as well as those of the structural types. The possible different sensitivity of these structures to environmental changes is still unknown. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Anisospira velascorum, a new land snail from Mexico, with notes on the anatomy and histology (Mollusca, Gastropoda, Urocoptidae)

    NARCIS (Netherlands)

    Breure, A.S.H.

    1977-01-01

    During a collecting trip through southern and central Mexico (Breure, 1974) special attention has been paid to Bulimulidae and Urocoptidae. Among the material of urocoptids a new species has been found. Anisospira velascorum sp. n. (figs. 1-10, pl. 1) Description. — Shell up to 30.5 mm, 2.39 times

  3. Thais (Stramonita rustica (Lamarck, 1822 (Mollusca: Gastropoda: Thaididae, a potential bioindicator of contamination by organotin northeast Brazil

    Directory of Open Access Journals (Sweden)

    Ítalo Braga de Castro

    2004-06-01

    Full Text Available The use of antifouling paints containing the biocide compound tributyltin (TBT has been shown as an inductor of imposex in neogastropods mollusks. Imposex is characterized by the development of male features in females, mainly the appearance of a no functional vas deferens and penis. Samples of Thais rustica were collected in eight sites in the metropolitan area of Natal city, Rio Grande do Norte state, northeast Brazil, and examined for occurrence of imposex, which was found in many females. The higher imposex levels were presented by samples from sites near city harbor.A utilização de tintas antiincrustrantes contendo o composto biocida tributilestanho (TBT tem induzido moluscos neogastrópodes ao imposex. O imposex é caracterizado pelo surgimento de caracteres sexuais masculinos, sobretudo, pênis e vaso deferente não funcionais em fêmeas desses moluscos. Foram coletadas amostras de Thais rústica em oito estações ao longo da costa da cidade de Natal no Rio Grande do Norte. Esses animais foram analisados quanto a presença e o grau de imposex que apresentavam. Os níveis mais elevados de imposex foram observados na estação mais próxima ao porto.

  4. Bioindicator Thais carinifera (mollusca, gastropoda: imposex response and consequences along the Pakistan coast during the period from 1993 to 2012

    Directory of Open Access Journals (Sweden)

    Nuzhat Afsar

    2015-06-01

    Full Text Available Abstract Endocrine mediated "imposex" phenomenon was investigated and recorded in the muricoid gastropod species Thais carinifera during the two decades from 1993 to 2012 at three (3 sites out of six (6 localities investigated along the Sindh and Balochistan coast, Pakistan. The VDS stages 1 to 4 were apparent in Thais carinifera. The intensity of imposex has remained comparatively low in the populations of harbours in close proximity to port Mohammad Bin-Qasim, namely; Old Korangi Fish Harbour (OKFH and New Korangi Fish Harbour (NKFH where shipping activities are sporadic as compared to those in Manora Channel and the adjoining Karachi Port area where intensive shipping activity is rather frequent. Target species found to be good bioindicators have shown a marked decrease over the prolonged study period. Investigations show that this decrease is solely due to globally imposed effective bans on tributyltin (TBT based antifouling paints over the past decade.

  5. Assessment of tributyltin contamination based on imposex in Stramonita rustica (Mollusca: Gastropoda along southern Bahia coast, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    G. C. Zeidan

    Full Text Available Abstract This study investigated the effects of tributyltin (TBT on the morphology of the genital system of the gastropod Stramonita rustica in southern Bahia, Brazil. For this, 330 specimens were collected during the summer of 2014 at eight sampling points to ascertain whether male sex organs had developed in addition to the complete female genital tract in females (= imposex. The analyses were made under a stereoscopic microscope. Imposex and their associated indexes, and the sterile females, exhibited the highest rates in harbors and shipyards areas. Despite the total ban of TBT in anti-fouling paints on a global scale since 2003, the results of this and other studies indicate the continued use of those paints on the Brazilian coast. This shows the inefficiency of existing legislation and the need to strengthen enforcement of the ban.

  6. Assessment of tributyltin contamination based on imposex in Stramonita rustica (Mollusca: Gastropoda) along southern Bahia coast, northeastern Brazil.

    Science.gov (United States)

    Zeidan, G C; Boehs, G

    2017-03-01

    This study investigated the effects of tributyltin (TBT) on the morphology of the genital system of the gastropod Stramonita rustica in southern Bahia, Brazil. For this, 330 specimens were collected during the summer of 2014 at eight sampling points to ascertain whether male sex organs had developed in addition to the complete female genital tract in females (= imposex). The analyses were made under a stereoscopic microscope. Imposex and their associated indexes, and the sterile females, exhibited the highest rates in harbors and shipyards areas. Despite the total ban of TBT in anti-fouling paints on a global scale since 2003, the results of this and other studies indicate the continued use of those paints on the Brazilian coast. This shows the inefficiency of existing legislation and the need to strengthen enforcement of the ban.

  7. Imposex induction in Stramonita haemastoma floridana (Conrad, 1837 (Mollusca: Gastropoda: Muricidae submitted to an organotin-contaminated diet

    Directory of Open Access Journals (Sweden)

    Aline Fernandes Alves de Lima

    2006-03-01

    Full Text Available Marine organisms are affected by organotin compounds due to the cumulative, deleterious effects of these latter. The most evident and well known consequence of organotin contamination is imposex, a hormonal disruption that causes a superimposition of sexual male features in females of prosobranchia neogastropod molluscs such as Stramonita haemastoma floridana. Molluscs accumulate organotins mainly because of their poor ability to eliminate TBT and DBT from their tissues. The aim of this study was to analyze organotin uptake by ingestion experimentally, using uncontaminated subjects (S. haemastoma floridana fed with organotin-contaminated oysters (Crassostrea rhizophorae. A total of 248 gastropods, distributed in 7 tanks with uncontaminated water and contaminated food, were used in this study, a control group being fed uncontaminated oysters. Every 15 days, the individuals of one of the tanks were examined for the presence of imposex. Development of imposex was measured using the VDSI, RPSI and RPLI indexes. The animals had already developed imposex within the first 15 days, all the indexes measured (RPLI, RPSI and VDSI having increased significantly with duration of exposure, indicating that the animals were probablycontaminated by the food and had accumulated the pollutant. New paths of imposex development were also observed.Organismos marinhos são afetados por compostos organoestânicos que causam uma série de efeitos deletérios aos mesmos. O mais conhecido efeito da contaminação por organoestânicos é o imposex. Esse fenômeno consiste na masculinização de fêmeas de moluscos neogastrópodes tais como Stramonita haemastoma floridana. Esses compostos tendem a se acumular em moluscos devido a sua baixa capacidade de eliminá-los. Um total de 248 indivíduos de S. haemastoma floridana foram coletados de uma população livre qualquer indício de imposex. Esses animais foram mantidos em 7 aquários, com aproximadamente 30 indivíduos cada, 1 desses aquários foi considerado como controle e os animas do mesmo alimentados com ostras obtidas de locais onde não se verificou a ocorrência de imposex em neogastrópodes nativos. Os animais nos outros 6 aquários foram alimentados com ostras obtidas em local onde a incidência de imposex entre os gastrópodes nativos revelou-se muito alta. A cada 15 dias, por um período total de 90 dias, os animais de um dos tanques eram retirados e analisados quanto à presença de imposex. Os níveis de imposex foram quantificados através da % de imposex e dos índices: RPLI, RPSI e VDSI. Observou-se a indução de imposex em S. haemastoma floridana através da dieta a partir de Crassostrea rhizophora e um aumento significativo dos índices com o decorrer do tempo de exposição. Os animais do aquário controle foram analisados ao fim do experimento não revelando qualquer indício de imposex.

  8. Comparative sensitivity of juvenile and adult Potamopyrgus antipodarum (Mollusca: Hydrobiidae) under chronic exposure to cadmium and tributyltin.

    Science.gov (United States)

    Ruppert, Katharina; Geiß, Cornelia; Ostermann, Sina; Theis, Christina; Oehlmann, Jörg

    2016-07-28

    To investigate a potential extension of a partial life cycle test protocol to a full life cycle test design, a comparative sensitivity analysis with juvenile and adult Potamopyrgus antipodarum was performed. Neonates and adult snails were exposed to the metal cadmium (Cd) and the endocrine disruptor tributyltin (TBT) at nominal concentrations ranging from 1.56 to 50 μg Cd/L and from 25 to 1,000 ng TBT-Sn/L. The experiments were performed over 28 days at 16°C in a semi-static test design. Mortality was assessed for both life stages. Juvenile snails' specific growth rate and reproduction of adults were investigated as main endpoints. We determined effects on snails' survival, juvenile growth and embryo numbers in the brood pouch of adult snails under exposure to both chemicals. Juvenile control mortality was between 25% and 30% and significantly higher than in the control groups with adult snails. A higher sensitivity of juvenile snails compared to adults was observed for the endpoint mortality. Calculated LC50 in Cd exposed snails was 38.2 μg/L for adults and 15.0 μg/L for juvenile snails. Significant effects on mortality in TBT exposed adult snails occurred at the highest test concentration only with a LC50 of 535 ng Sn/L. Juvenile survival was significantly affected at 50.8 ng Sn/L and higher concentrations. Effect concentrations for the main endpoints reproduction and juvenile growth show comparable sensitivities. For Cd exposed groups, EC50 values were 11.3 μg/L for the endpoint reproduction in adult snails and 3.82 μg/L for juvenile growth with overlapping confidence intervals. TBT also significantly affected juvenile snails' growth (EC50: 178 ng Sn /L). EC50 for embryo numbers was 125 ng TBT-Sn/L. Results indicate the manageability of a FLC test starting with newly hatched snails. Precautions have to be taken to guarantee a sufficient number of surviving snails until adulthood so that reproduction can be assessed. For final decision for the practicability of a FLC, further tests are needed.

  9. Development and validation of an OECD reproductive toxicity test guideline with the mudsnail Potamopyrgus antipodarum (Mollusca, Gastropoda).

    Science.gov (United States)

    Ruppert, Katharina; Geiß, Cornelia; Askem, Clare; Benstead, Rachel; Brown, Rebecca; Coke, Maira; Ducrot, Virginie; Egeler, Philipp; Holbech, Henrik; Hutchinson, Thomas H; Kinnberg, Karin L; Lagadic, Laurent; Le Page, Gareth; Macken, Ailbhe; Matthiessen, Peter; Ostermann, Sina; Schimera, Agnes; Schmitt, Claudia; Seeland-Fremer, Anne; Smith, Andy J; Weltje, Lennart; Oehlmann, Jörg

    2017-08-01

    Mollusks are known to be uniquely sensitive to a number of reproductive toxicants including some vertebrate endocrine disrupting chemicals. However, they have widely been ignored in environmental risk assessment procedures for chemicals. This study describes the validation of the Potamopyrgus antipodarum reproduction test within the OECD Conceptual Framework for Endocrine Disrupters Testing and Assessment. The number of embryos in the brood pouch and adult mortality serve as main endpoints. The experiments are conducted as static systems in beakers filled with artificial medium, which is aerated trough glass pipettes. The test chemical is dispersed into the medium, and adult snails are subsequently introduced into the beakers. After 28 days the reproductive success is determined by opening the brood pouch and embryo counting. This study presents the results of two validation studies of the reproduction test with eleven laboratories and the chemicals tributyltin (TBT) with nominal concentrations ranging from 10 to 1000 ng TBT-Sn/L and cadmium with concentrations from 1.56 to 25 μg/L. The test design could be implemented by all laboratories resulting in comparable effect concentrations for the endpoint number of embryos in the brood pouch. After TBT exposure mean EC 10 , EC 50 , NOEC and LOEC were 35.6, 127, 39.2 and 75.7 ng Sn/L, respectively. Mean effect concentrations in cadmium exposed snails were, respectively, 6.53, 14.2, 6.45 and 12.6 μg/L. The effect concentrations are in good accordance with already published data. Both validation studies show that the reproduction test with P. antipodarum is a well-suited tool to assess reproductive effects of chemicals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Symbiotic relationship between the carapid fish Onuxodon fowleri (Ophidiiformes: Carapidae and the pearl oyster Pinctada margaritifera (Mollusca: Bivalvia: Pteriidae

    Directory of Open Access Journals (Sweden)

    Orphal Colleye

    2018-03-01

    Full Text Available At Makemo Atoll (French Polynesia, the carapid fish Onuxodon fowleri lives in symbiosis with the black-lip pearl oyster Pinctada margaritifera. Although the symbiont seems to live inside its host bivalve by using it as a shelter, additional data are still needed to better understand the exact nature of this association. For this purpose, we implemented an approach using stable isotope ratios of carbon (13C/12C and nitrogen (15N/14N. The δ13C and δ15N values were measured in tissues of the pearl oyster (gonads, gills, mantle and muscles, white muscle tissue from the fish and other food sources. This stable isotope approach was also complemented by the analysis of stomach contents in the carapid fish. Overall, the isotopic compositions measured in the present study support a commensal relationship between O. fowleri and P. margaritifera. In addition, our isotopic data bring new information about another guest living inside P. margaritifera, namely the palaemonid shrimp Conchodytes meleagrinae. Based on the δ13C and δ15N values, it appears that the shrimp might feed on the bivalve gonads.

  11. Phytochemical and molluscicidal activity of Mikania glomerata Sprengel (Asteraceae in different lifestages of Subulina octona (Mollusca, Subulinidade

    Directory of Open Access Journals (Sweden)

    Bruna Aparecida de Souza

    2014-04-01

    Full Text Available The objective of this work was to study the molluscicidal activity of aqueous extract of Mikania glomerata on the land snail Subulina octona and to assess the changes caused on the snail's fecundity, growth, hatchability and the offspring produced after exposure. Eggs, newly hatched and 30 day old snails were exposed to the sublethal concentration of M. glomerata extract for 24 and 48 h and the observations were made for 120 days. The presence of tannins, flavonoids and saponins were shown by phytochemical tests. The extract reduced significantly the hatchability and the survival of the offspring hatched from the exposed eggs. The eggs exposed for 48 h presented lower hatchability rates. There was a reduction on survival and growth of newly hatched and 30-days old snails exposed to the extract. These results indicated that the aqueous extract of M. glomerata could be applied as an alternative molluscicide for the control of this snail species efficiently.

  12. Diversidade e distribuição do gênero Alvania (Mollusca, Gastropoda: Rissoidae) no litoral brasileiro

    OpenAIRE

    SILVA, Luciana Soares da

    2012-01-01

    Os Rissoidae Gray, 1847 são compostos por conchas pequenas ou micro-conchas, abundantes nos mares de todo mundo. Uma grande diversidade das espécies desse grupo é encontrada nas zonas de maré baixa e ao longo do litoral, onde há a maior ocorrência de algas, rochas, corais e outros locais que fornecem abrigo, todavia muitos ocorrem também em zonas de mar profundo. Em Rissoidae, Alvania é um dos mais diversos quanto ao número de espécies, sendo frequentes as descrições ou re-descrições de...

  13. Size and metal concentration in the mangrove mussel Mytella guyanensis (Mollusca: Bivalva) from Baia de Sepetiba, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    de Lacerda, L.D.; Lima, N.R.W.; Pfeiffer, W.C.; Fiszman, M.

    1983-11-01

    The natural variability of metal concentrations in M. guyanensis was estimated. The chosen parameter was size, as it is well correlated with most other metabolic functions and is of major concern in developing monitoring programs. The sampled area is in the mangrove swamp of Itingussu, Baia de Sepetiba, Rio de Janerio State, an area with increasing industrial activity and consequently with moderate levels of heavy metals in the aquatic environment. The analysis of metals in shells showed a significant inverse relationship for all metals, presenting a constant trend not observed in soft tissues. As the mechanisms of metal uptake and excretion in shells are slower than those of soft tissues, shells should be used as monitoring instruments. The results suggest that the relation between metal concentration and size in mollusks is a significant factor to be considered in monitoring programs. These relationships vary with species, and care should be taken in considering results obtained in species from temperature regions and those from the tropics, even when the species are closely related. 7 references, 2 figures, 1 table.

  14. A Carboniferous chiton (Mollusca, Polyplacophora) at the end of its trail: a unique find from the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Mikuláš, Radek; Rindsberg, A. K.; Santos, A.; Pavela, M.

    2017-01-01

    Roč. 56, č. 2 (2017), s. 171-179 ISSN 0375-7633 Institutional support: RVO:67985831 Keywords : Viséan * Recent * locomotion traces * tracemakers * Proleptochiton Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 0.903, year: 2016

  15. Imposex in Thais rustica (Mollusca: Neogastropoda (Lamark, 1822 as an indicator of organotin compounds pollution at Maceio coast (Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Edmundo Camillo

    2004-06-01

    Full Text Available The use of OTC (organotin compounds as biocides in naval antifouling paints causes impacts on non-target organisms. One of these impacts is a syndrome called imposex in gastropod molluscs. Imposex is the imposition of male secondary sexual characteristics in female gastropods as result of endocrine disruption. In this preliminary study, imposex was observed in four out of ten sampled stations in Maceió: the city Port (100% females exhibited imposex, the Marine Emissary (23% females exhibited imposex, the Marine Terminal (35% females exhibited imposex and Saco da Pedra beach (12% females exhibited imposex. These stations were distributed in a NE-SW orientation from the Port southwards along the coastline, following the general circulation pattern of the area. The low values of VDSI, RPSI and RPLI indicate that Maceió Coast is a less contaminated area, probably because of low shipping activities together with the fact that the sampling zone is an open coastal system and not an enclosed bay. These results suggest that the imposex development in Thais rustica may be used as a biological indicator of OTC pollution.O uso de COE (compostos orgânicos de estanho como biocida em tintas antiincrustantes para embarcações causa impactos em organismos não-alvos. Um destes impactos é a síndrome chamada imposex, em moluscos gastrópodos. Imposex é a imposição de caracteres sexuais secundários masculinos em fêmeas de gastrópodos como resultado de desregulação endócrina. Neste estudo preliminar, o imposex foi observado em quatro de dez estações de amostragem em Maceió: o Porto de Maceió (100% de fêmeas imposexadas, o Emissário Submarino (23% de fêmeas imposexadas, o Terminal Marítimo (35% de fêmeas imposexadas e a praia do Saco da Pedra (12% de fêmeas imposexadas. Estas estações estão distribuídas no litoral no sentido NE/SW a partir do Porto, seguindo o padrão de circulação local. Os valores relativamente baixos dos índices VDSI, RPSI e RPLI indicam que a costa de Maceió é uma área moderadamente impactada. Isto poderia ser explicado pelo fato da costa não ser um sistema abrigado e pelo pequeno movimento de sua zona portuária. Estes resultados sugerem que o desenvolvimento do imposex em Thais rustica pode ser usado como indicador da poluição por COEs.

  16. On growth and form of irregular coiled-shell of a terrestrial snail: Plectostoma concinnum (Fulton, 1901) (Mollusca: Caenogastropoda: Diplommatinidae).

    Science.gov (United States)

    Liew, Thor-Seng; Kok, Annebelle C M; Schilthuizen, Menno; Urdy, Severine

    2014-01-01

    The molluscan shell can be viewed as a petrified representation of the organism's ontogeny and thus can be used as a record of changes in form during growth. However, little empirical data is available on the actual growth and form of shells, as these are hard to quantify and examine simultaneously. To address these issues, we studied the growth and form of a land snail that has an irregularly coiled and heavily ornamented shell-Plectostoma concinnum. The growth data were collected in a natural growth experiment and the actual form changes of the aperture during shell ontogeny were quantified. We used an ontogeny axis that allows data of growth and form to be analysed simultaneously. Then, we examined the association between the growth and the form during three different whorl growing phases, namely, the regular coiled spire phase, the transitional constriction phase, and the distortedly-coiled tuba phase. In addition, we also explored the association between growth rate and the switching between whorl growing mode and rib growing mode. As a result, we show how the changes in the aperture ontogeny profiles in terms of aperture shape, size and growth trajectory, and the changes in growth rates, are associated with the different shell forms at different parts of the shell ontogeny. These associations suggest plausible constraints that underlie the three different shell ontogeny phases and the two different growth modes. We found that the mechanism behind the irregularly coiled-shell is the rotational changes of the animal's body and mantle edge with respect to the previously secreted shell. Overall, we propose that future study should focus on the role of the mantle and the columellar muscular system in the determination of shell form.

  17. Potentiality of Achatina fulica Bowdich, 1822 (Mollusca: Gastropoda as intermediate host of the Angiostrongylus costaricensis Morera & Céspedes 1971

    Directory of Open Access Journals (Sweden)

    Carvalho Omar dos Santos

    2003-01-01

    Full Text Available Samples of Achatina fulica were experimentally infected with Angiostrongylus costaricensis larvae, etiological agent of abdominal angiostrongyliasis, showing that A. fulica is susceptible to the parasite. Achatina fulica may be a risk to urbanization of abdominal angiostrongyliasis presumably due to its high proliferation, continuous dispersion and remarkable adaptation in several Brazilian towns.

  18. First record of a nematode Metastrongyloidea (Aelurostrongylus abstrusus larvae) in Achatina (Lissachatina) fulica (Mollusca, Achatinidae) in Brazil.

    Science.gov (United States)

    Thiengo, Silvana C; Fernandez, Monica A; Torres, Eduardo J L; Coelho, Pablo M; Lanfredi, Reinalda M

    2008-05-01

    Achatina (Lissachatina) fulica was introduced in Brazil in the 1980s for commercial purposes ("escargot" farming) and nowadays, mainly by human activity, it is widespread in at least 23 out of 26 Brazilian states and Brasília, including the Amazonian region and natural reserves, where besides a general nuisance for people it is a pest and also a public health concern, since it is one of the natural intermediate host of Angiostrongylus cantonensis, ethiological agent of the meningoencephalitis in Asia. As Brazil is experiencing the explosive phase of the invasion, the Laboratório de Malacologia do Instituto Oswaldo Cruz/Fiocruz has been receiving samples of these molluscs for identification and search for Angiostrongylus cantonensis and Angiostrongylus costaricensis larvae. While examining samples of A. fulica different nematode larvae were obtained, including Aelurostrongylus, whose different species are parasites of felids, dogs, primates, and badger. Morphological and morphometric analyses presented herein indicated the species Aelurostrongylus abstrusus, as well as the occurrence of other nematode larvae (Strongyluris-like) found in the interior of the pallial cavity of A. fulica. This is the first report in Brazil of the development of A. abstrusus infective larvae in A. fulica evidencing the veterinary importance of this mollusc in the transmission of A. abstrusus to domestic cats. Since the spread of A. fulica is pointed out in the literature as one of the main causative spread of the meningoencephalitis caused by A. cantonensis the authors emphasize the need of sanitary vigilance of snails and rats from vulnerable areas for A. cantonensis introduction as the port side areas.

  19. First report of Angiostrongylus cantonensis (Nematoda: Metastrongylidae in Achatina fulica (Mollusca: Gastropoda from Southeast and South Brazil

    Directory of Open Access Journals (Sweden)

    Arnaldo Maldonado Júnior

    2010-11-01

    Full Text Available The rat lungworm Angiostrongylus cantonensis is a worldwide-distributed zoonotic nematode that can cause human eosinophilic meningoencephalitis. Here, for the first time, we report the isolation of A. cantonensis from Achatina fulica from two Brazilian states: Rio de Janeiro (specifically the municipalities of Barra do Piraí, situated at the Paraiba River Valley region and São Gonçalo, situated at the edge of Guanabara Bay and Santa Catarina (in municipality of Joinville. The lungworms were identified by comparing morphological and morphometrical data obtained from adult worms to values obtained from experimental infections of A. cantonensis from Pernambuco, Brazil, and Akita, Japan. Only a few minor morphological differences that were determined to represent intra-specific variation were observed. This report of A. cantonensis in South and Southeast Brazil, together with the recent report of the zoonosis and parasite-infected molluscs in Northeast Brazil, provide evidence of the wide distribution of A. cantonensis in the country. The need for efforts to better understand the role of A. fulica in the transmission of meningoencephalitis in Brazil and the surveillance of molluscs and rodents, particularly in ports, is emphasized.

  20. Potentiality of Achatina fulica Bowdich, 1822 (Mollusca: Gastropoda) as intermediate host of the Angiostrongylus costaricensis Morera & Céspedes 1971.

    Science.gov (United States)

    Carvalho, Omar dos Santos; Teles, Horácio M; Mota, Ester Maria; Lafetá, Cristiane; de Mendonça, Gomes Furtado; Lenzi, Henrique Leonel

    2003-01-01

    Samples of Achatina fulica were experimentally infected with Angiostrongylus costaricensis larvae, etiological agent of abdominal angiostrongyliasis, showing that A. fulica is susceptible to the parasite. Achatina fulica may be a risk to urbanization of abdominal angiostrongyliasis presumably due to its high proliferation, continuous dispersion and remarkable adaptation in several Brazilian towns.

  1. First report of Angiostrongylus cantonensis (Nematoda: Metastrongylidae) in Achatina fulica (Mollusca: Gastropoda) from Southeast and South Brazil.

    Science.gov (United States)

    Maldonado, Arnaldo; Simões, Raquel O; Oliveira, Ana Paula M; Motta, Esther M; Fernandez, Mônica A; Pereira, Zilene M; Monteiro, Simone S; Torres, Eduardo J Lopes; Thiengo, Silvana Carvalho

    2010-11-01

    The rat lungworm Angiostrongylus cantonensis is a worldwide-distributed zoonotic nematode that can cause human eosinophilic meningoencephalitis. Here, for the first time, we report the isolation of A. cantonensis from Achatina fulica from two Brazilian states: Rio de Janeiro (specifically the municipalities of Barra do Piraí, situated at the Paraiba River Valley region and São Gonçalo, situated at the edge of Guanabara Bay) and Santa Catarina (in municipality of Joinville). The lungworms were identified by comparing morphological and morphometrical data obtained from adult worms to values obtained from experimental infections of A. cantonensis from Pernambuco, Brazil, and Akita, Japan. Only a few minor morphological differences that were determined to represent intra-specific variation were observed. This report of A. cantonensis in South and Southeast Brazil, together with the recent report of the zoonosis and parasite-infected molluscs in Northeast Brazil, provide evidence of the wide distribution of A. cantonensis in the country. The need for efforts to better understand the role of A. fulica in the transmission of meningoencephalitis in Brazil and the surveillance of molluscs and rodents, particularly in ports, is emphasized.

  2. Potentiality of Achatina fulica Bowdich, 1822 (Mollusca: Gastropoda) as intermediate host of the Angiostrongylus costaricensis Morera & Céspedes 1971

    OpenAIRE

    Carvalho, Omar dos Santos; Teles, Horácio MS; Mota, Ester Maria; Mendonça, Cristiane Lafetá Gomes Furtado de; Lenzi, Henrique Leonel

    2003-01-01

    Samples of Achatina fulica were experimentally infected with Angiostrongylus costaricensis larvae, etiological agent of abdominal angiostrongyliasis, showing that A. fulica is susceptible to the parasite. Achatina fulica may be a risk to urbanization of abdominal angiostrongyliasis presumably due to its high proliferation, continuous dispersion and remarkable adaptation in several Brazilian towns. Exemplares de Achatina fulica foram experimentalmente infectados com larvas de Angiostrongylu...

  3. Immunochemical localization of ribulose-1,5-bisphosphate carboxylase in the symbiont-containing gills of Solemya velum (Bivalvia : Mollusca)

    NARCIS (Netherlands)

    Cavanaugh, Colleen M.; Abbott, Marilyn S.; Veenhuis, Marten

    1988-01-01

    The distribution of the Calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase (RbuP2Case; EC 4.1.1.39) was examined by using two immunological methods in tissues of Solemya velum, an Atlantic coast bivalve containing putative chemoautotrophic symbionts. Antibodies elicited by the purified large

  4. Immunochemical localization of ribulose-1,5-bisphosphate carboxylase in the symbiont-containing gills of Solemya velum (Bivalvia: Mollusca).

    Science.gov (United States)

    Cavanaugh, C M; Abbott, M S; Veenhuis, M

    1988-10-01

    The distribution of the Calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase (RbuP(2)Case; EC 4.1.1.39) was examined by using two immunological methods in tissues of Solemya velum, an Atlantic coast bivalve containing putative chemoautotrophic symbionts. Antibodies elicited by the purified large subunit of RbuP(2)Case from tobacco (Nicotiana tabacum) cross-reacted on immunoblots with a protein of similar molecular mass occurring in extracts of the symbiont-containing gill tissue of S. velum. No cross-reactivity was detected in symbiont-free tissue extracts. The antiserum also cross-reacted in immunoblots with proteins of Thiobacillus neapolitanus, a free-living sulfuroxidizing chemoautotroph whose RbuP(2)Case has been well characterized. In protein A-gold immunoelectron microscopy studies, this antiserum consistently labeled the symbionts but not surrounding host gill tissue, indicating that the symbionts are responsible for the RbuP(2)Case activity.

  5. Microsatellite loci for dreissenid mussels (Mollusca: Bivalvia: Dreissenidae) and relatives: markers for assessing exotic and native populations.

    Science.gov (United States)

    Feldheim, Kevin A; Brown, Joshua E; Murphy, Douglas J; Stepien, Carol A

    2011-07-01

    We developed and tested 14 new polymorphic microsatellite loci for dreissenid mussels, including the two species that have invaded many freshwater habitats in Eurasia and North America, where they cause serious industrial fouling damage and ecological alterations. These new loci will aid our understanding of their genetic patterns in invasive populations as well as throughout their native Ponto-Caspian distributions. Eight new loci for the zebra mussel Dreissena polymorpha polymorpha and six for the quagga mussel D. rostriformis bugensis were compared with new results from six previously published loci to generate a robust molecular toolkit for dreissenid mussels and their relatives. Taxa tested include D. p. polymorpha, D. r. bugensis, D. r. grimmi, D. presbensis, the 'living fossil'Congeria kusceri, and the dark false mussel Mytilopsis leucophaeata (the latter also is invasive). Overall, most of the 24 zebra mussel (N = 583) and 13 quagga mussel (N = 269) population samples conformed to Hardy-Weinberg equilibrium expectations for the new loci following sequential Bonferroni correction. The 11 loci (eight new, three previously published) evaluated for D. p. polymorpha averaged 35.1 alleles and 0.72 mean observed heterozygosity per locus, and 25.3 and 0.75 for the nine loci (six new, three previously published) developed for D. r. bugensis. All but three of these loci successfully amplified the other species of Dreissena, and all but one also amplified Congeria and Mytilopsis. All species and populations tested were significantly divergent using the microsatellite data, with neighbour-joining trees reflecting their evolutionary relationships; our results reveal broad utility for resolving their biogeographic, evolutionary, population and ecological patterns. © 2011 Blackwell Publishing Ltd.

  6. Effects of food type, feeding frequency, and temperature on juvenile survival and growth of Marisa cornuarietis (Mollusca: Gastropoda).

    Science.gov (United States)

    Selck, Henriette; Aufderheide, John; Pounds, Nadine; Staples, Charles; Caspers, Norbert; Forbes, Valery

    2006-06-01

    The present experiments are part of a larger study designed to investigate the influence of husbandry parameters on the life history of the ramshorn snail, Marisa cornuarietis, in order to identify suitable husbandry conditions for maintaining multi-generation populations in the laboratory for use in ecotoxicological testing. In this paper we focus on the effects of a combination of food types and feeding frequencies (i.e., the frequency with which the snails were offered food) on juvenile growth and survival at different temperatures. Offspring produced in the laboratory by wild specimens of M. cornuarietis, from Puerto Rico, were used to test the effects of three types of food (lettuce, alginate with fish food, alginate with snail mix) fed at three frequencies (given ad libitum on 4/4, 2/4, or 1/4 d) on juvenile survival and growth. The 4-d feeding regimens were repeated four times, giving a total of 16 d for the experiments. The experiments were conducted at two temperatures (22 degrees and 25 degrees C) under a 12 h light:12 h dark photoperiod. Juvenile growth rates increased with increasing feeding frequency for all food types. The most rapid growth rates occurred in the high-frequency lettuce treatments and the slowest growth rates in the low-frequency lettuce and alginate with snail mix treatments. Juvenile snails grew faster at 25 degrees than at 22 degrees C, and mortality was about twice as high at the lower temperature. Growth rates were used to provide a rough estimate of time to maturity, which was determined to take about twice as long at 22 degrees than at 25 degrees C. The results showed that lettuce is the best food if supplied in abundance, but effects on growth are very dependent on feeding frequency and temperature. We conclude that 25 degrees C is a more appropriate temperature for maintaining populations than 22 degrees C, that lettuce provides a suitable food source, and that food should be supplied continuously for husbandry and toxicity testing of populations of M. cornuarietis.

  7. Effects of food type, feeding frequency, and temperature on juvenile survival and growth of Marisa cornuarietis (Mollusca: Gastropoda)

    OpenAIRE

    Selck, Henriette; Aufderheide, John; Pounds, Nadine; Staples, Charles; Caspers, Norbert; Forbes, Valery

    2006-01-01

    The present experiments are part of a larger study designed to investigate the influence of husbandry parameters on the life history of the ramshorn snail, Marisa cornuarietis, in order to identify suitable husbandry conditions for maintaining multi-generation populations in the laboratory for use in ecotoxicological testing. In this paper we focus on the effects of a combination of food types and feeding frequencies (i.e., the frequency with which the snails were offered food) on juvenile gr...

  8. Development and validation of an OECD reproductive toxicity test guideline with the mudsnail Potamopyrgus antipodarum (Mollusca, Gastropoda)

    DEFF Research Database (Denmark)

    Ruppert, Katharina; Geiß, Cornelia; Askem, Clare

    2017-01-01

    Mollusks are known to be uniquely sensitive to a number of reproductive toxicants including some vertebrate endocrine disrupting chemicals. However, they have widely been ignored in environmental risk assessment procedures for chemicals. This study describes the validation of the Potamopyrgus ant...

  9. Development and validation of an OECD reproductive toxicity test guideline with the pond snail Lymnaea stagnalis (Mollusca, Gastropoda).

    Science.gov (United States)

    Ducrot, Virginie; Askem, Clare; Azam, Didier; Brettschneider, Denise; Brown, Rebecca; Charles, Sandrine; Coke, Maïra; Collinet, Marc; Delignette-Muller, Marie-Laure; Forfait-Dubuc, Carole; Holbech, Henrik; Hutchinson, Thomas; Jach, Arne; Kinnberg, Karin L; Lacoste, Cédric; Le Page, Gareth; Matthiessen, Peter; Oehlmann, Jörg; Rice, Lynsey; Roberts, Edward; Ruppert, Katharina; Davis, Jessica Elphinstone; Veauvy, Clemence; Weltje, Lennart; Wortham, Ruth; Lagadic, Laurent

    2014-12-01

    The OECD test guideline development program has been extended in 2011 to establish a partial life-cycle protocol for assessing the reproductive toxicity of chemicals to several mollusk species, including the great pond snail Lymnaea stagnalis. In this paper, we summarize the standard draft protocol for a reproduction test with this species, and present inter-comparison results obtained in a 56-day prevalidation ring-test using this protocol. Seven European laboratories performed semi-static tests with cultured snails of the strain Renilys® exposed to nominal concentrations of cadmium chloride (from 53 to 608μgCdL(-1)). Cd concentrations in test solutions were analytically determined to confirm accuracy in the metal exposure concentrations in all laboratories. Physico-chemical and biological validity criteria (namely dissolved oxygen content >60% ASV, water temperature 20±1°C, control snail survival >80% and control snail fecundity >8 egg-masses per snail over the test period) were met in all laboratories which consistently demonstrated the reproductive toxicity of Cd in snails using the proposed draft protocol. Effect concentrations for fecundity after 56days were reproducible between laboratories (68

  10. Genetic differentiation of Octopus minor (Mollusca, Cephalopoda) off the northern coast of China as revealed by amplified fragment length polymorphisms.

    Science.gov (United States)

    Yang, J M; Sun, G H; Zheng, X D; Ren, L H; Wang, W J; Li, G R; Sun, B C

    2015-12-02

    Octopus minor (Sasaki, 1920) is an economically important cephalopod that is found in the northern coastal waters of China. In this study, we investigated genetic differentiation in fishery populations using amplified fragment length polymorphisms (AFLPs). A total of 150 individuals were collected from five locations: Dalian (DL), Yan-tai (YT), Qingdao (QD), Lianyungang (LY), and Zhoushan (ZS), and 243 reproducible bands were amplified using five AFLP primer combinations. The percentage of polymorphic bands ranged from 53.33 to 76.08%. Nei's genetic identity ranged from 0.9139 to 0.9713, and the genetic distance ranged from 0.0291 to 0.0900. A phylogenetic tree was constructed using the unweighted pair group method with arithmetic mean, based on the genetic distance. The DL and YT populations originated from one clade, while the QD, LY, and ZS populations originated from another. The results indicate that the O. minor stock consisted of two genetic populations with an overall significantly analogous FST value (0.1088, P octopus fisheries, so that this marine resource can be conserved for its long-term utilization.

  11. Fine structure of the creeping larva of Loxosomella murmanica: additional evidence for a clade of Kamptozoa (Entoprocta) and Mollusca

    DEFF Research Database (Denmark)

    Haszprunar, Gerhard; Wanninger, Andreas Wilhelm Georg

    2008-01-01

    . The prototroch consists of two ciliary rings; a downstream collecting system is not present. Although there is a one-way gut with a lumen throughout, the larva obviously does not feed. A single pair of protonephridia is present. The foot sole shares distinct similarities with basic molluscs, particularly...

  12. Annotated type catalogue of the Megaspiridae, Orthalicidae, and Simpulopsidae (Mollusca, Gastropoda, Orthalicoidea in the Natural History Museum, London

    Directory of Open Access Journals (Sweden)

    Abraham S.H. Breure

    2015-01-01

    Full Text Available The type status is described for 65 taxa of the Orthalicoidea, classified within the families Megaspiridae (14, Orthalicidae (30, and Simpulopsidae (20; one taxon is considered a nomen inquirendum. Lectotypes are designated for the following taxa: Helix brephoides d’Orbigny, 1835; Simpulopsis cumingi Pfeiffer, 1861; Bulimulus (Protoglyptus dejectus Fulton, 1907; Bulimus iris Pfeiffer, 1853. The type status of Bulimus salteri Sowerby III, 1890, and Strophocheilus (Eurytus subirroratus da Costa, 1898 is now changed to lectotype according Art. 74.6 ICZN. The taxa Bulimus loxostomus Pfeiffer, 1853, Bulimus marmatensis Pfeiffer, 1855, Bulimus meobambensis Pfeiffer, 1855, and Orthalicus powissianus var. niveus Preston 1909 are now figured for the first time. The following taxa are now considered junior subjective synonyms: Bulimus marmatensis Pfeiffer, 1855 = Helix (Cochlogena citrinovitrea Moricand, 1836; Vermiculatus Breure, 1978 = Bocourtia Rochebrune, 1882. New combinations are: Kuschelenia (Bocourtia Rochebrune, 1882; Kuschelenia (Bocourtia aequatoria (Pfeiffer, 1853; Kuschelenia (Bocourtia anthisanensis (Pfeiffer, 1853; Kuschelenia (Bocourtia aquila (Reeve, 1848; Kuschelenia (Bocourtia badia (Sowerby I, 1835; Kuschelenia (Bocourtia bicolor (Sowerby I, 1835; Kuschelenia (Bocourtia caliginosa (Reeve, 1849; Kuschelenia (Bocourtia coagulata (Reeve, 1849; Kuschelenia (Bocourtia cotopaxiensis (Pfeiffer, 1853; Kuschelenia (Bocourtia filaris (Pfeiffer, 1853; Kara indentata (da Costa, 1901; Clathrorthalicus magnificus (Pfeiffer, 1848; Simpulopsis (Eudioptus marmartensis (Pfeiffer, 1855; Kuschelenia (Bocourtia nucina (Reeve, 1850; Kuschelenia (Bocourtia ochracea (Morelet, 1863; Kuschelenia (Bocourtia peaki (Breure, 1978; Kuschelenia (Bocourtia petiti (Pfeiffer, 1846; Clathrorthalicus phoebus (Pfeiffer, 1863; Kuschelenia (Bocourtia polymorpha (d’Orbigny, 1835; Scholvienia porphyria (Pfeiffer, 1847; Kuschelenia (Bocourtia purpurata (Reeve, 1849; Kuschelenia (Bocourtia quechuarum Crawford, 1939; Quechua salteri (Sowerby III, 1890; Kuschelenia (Bocourtia subfasciata Pfeiffer, 1853; Clathrorthalicus victor (Pfeiffer, 1854. In an addedum a lectotype is being designated for Bulimulus (Drymaeus interruptus var. pallidus Preston, 1909. An index is included to all taxa mentioned in this paper and the preceding ones in this series (Breure and Ablett 2011, 2012, 2014.

  13. Biomonitoring study of an estuarine coastal ecosystem, the Sacca di Goro lagoon, using Ruditapes philippinarum (Mollusca: Bivalvia)

    International Nuclear Information System (INIS)

    Sacchi, Angela; Mouneyrac, Catherine; Bolognesi, Claudia; Sciutto, Andrea; Roggieri, Paola; Fusi, Marco; Beone, Gian Maria; Capri, Ettore

    2013-01-01

    Coastal lagoons are constantly subjected to releases of chemical pollutants, and so organisms may be exposed to such toxicants. This study investigated through a multivariate approach the physiological status of bivalve Ruditapes philippinarum, farmed in Sacca di Goro lagoon. Biomarkers at different levels of biological organization (catalase, superoxide dismutase, genotoxicity, reburrowing behavior) were evaluated at three sites exposed to different environmental conditions. A seasonal trend was observed, and micronucleus frequency was significantly lowest at the relatively pristine reference site. Enzymatic activity toward oxyradicals be quite efficient since variations in responsiveness were not consistent. However, behavioral impairment was observed in reburrowing rates. Sediment concentrations showed low PAH levels and high natural levels of trace metals Cr and Ni. DistLM statistical analysis revealed a non-significant relationship between selected biomarkers and xenobiotics. Therefore other potentially toxic compounds in admixture at low doses may be involved in driving differing spatial distribution of physiological impairment. -- Highlights: ► Health status assessment of bivalve Ruditapes philippinarum, from lagoon of Sacca di Goro. ► Multiparametric approach (chemical analysis, biochemical and behavioral biomarkers). ► Impairments of burrowing kinetics in the contaminated site. ► Micronucleus genotoxicity test to detect effects of contaminants complex mixture. ► Multiple stress of chemicals in estuarine costal ecosystem. -- The bivalve Ruditapes philippinarum as a bioindicator in monitoring pollution of estuaries

  14. Deep-water Mangeliinae, Taraninae and Clathurellinae (Mollusca: Gastropoda: Conoidea: Turridae from the Campos Basin, southeast Brazil

    Directory of Open Access Journals (Sweden)

    Raquel Medeiros Andrade Figueira

    2010-11-01

    Full Text Available During the program “Environmental Characterization of the Campos Basin, RJ, Brazil”, from 2001 to 2003, samples were taken of soft bottoms from the continental slope of Campos Basin (off southeast Brazil by the Research Vessel “Astro-Garoupa” with a 0.25 m2 box corer or by dredging with a Charcot dredge; 117 stations with depths from 700 to 1950 m were sampled. There were molluscs in all samples, and among Gastropoda the Turridae showed the highest diversity. Here we present the results obtained for the subfamilies Mangeliinae, Taraninae and Clathurellinae. Two species were found within Mangeliinae: Benthomangelia cf. macra (Watson, 1881 and Benthomangelia enceladus n. sp. Within Taraninae only one undescribed species was found: Taranis tanata n. sp. Within Clathurellinae we found four species: Corinnaeturris leucomata (Dall, 1881, recorded for the first time in the South Atlantic; Corinnaeturris rhysa (Watson, 1881, extending its described depth range; Corinnaeturris angularis n. sp., Typhlomangelia nivalis (Lovén, 1846, expanding its known distribution farther south; and Drilliola pulchella (Verrill, 1880. The type material of Drilliola loprestiana (Calcara, 1841, previously considered lost, has been located and is illustrated here. Drilliola crispata (Cristofori and Jan, 1832 is considered to be a nomen dubium.

  15. Dynamics and ecology of an Indo-Pacific conch,Conomurex persicus (Mollusca: Gastropoda in southeastern Turkey

    Directory of Open Access Journals (Sweden)

    Erhan Mutlu

    2006-03-01

    Full Text Available Conomurex persicus, one of the tropical conchs, has been introduced to one of the subtropical regions, the northeastern Mediterranean Sea, and invaded sandy bottoms between 1 and 10 m deep. Population dynamics were studied from specimens collected with a standard dredge (60 x 15 cm mouth opening, 0.5 x 0.5 cm eye opening of net. Samples of C. persicus were collected monthly along the 5 and 10 m depth contours off Erdemli, Mersin, Turkey, in February and May 2000. Intra-annual density depended on salinity levels, while inter-annual density was correlated with bottom water temperature. Specimens underwent spring emergences and winter burial and sheltering (disappearance. Emergence took place in March when temperatures rose and the disappearance occurred in October-November when temperatures dropped. Adults live at 10 m, juveniles are recruited at a 5 m depth. Recruitment began in April and continued for the next 6 months. In contrast to shell width or shell lip thickness, shell length was not a convenient index for estimation of growth parameters. Annual production and mortality were calculated to be 7.86 g m-2 and 3.80 g m-2, respectively, in April-November. Rev. Biol. Trop. 54 (1: 117-129. Epub 2006 Mar 31.El gastrópodo tropical Conomurex persicurs, ha sido introducido a una región subtropical, el noreste del Mar Mediterráneo, y ha invadido los fondos arenosos en un rango de profundidad de 1 a 10 m. Se estudiarion las dinámicas poblacionales a partir de especímenes recolectados mediante un dragado estándard (60 x 15 cm de apertura de entrada y 0.5 x 0.5 cm de tramado. Muestras de C. persicus fueron recolectadas mensualmente a produndidades de 5 y 10 m en las cercanías de Erdemil, Mersin, Turkey, en los meses de febrero y mayo del año 2000. La densidad dentro de un mismo año depende de los niveles de salinidad, mientras que al comparar años distintos está correlacionada con la temperatura del agua.

  16. Anatomy and systematics of Anodontites Elongatus (Swainson from Amazon and Parana Basins, Brazil (Mollusca, Bivalvia, Unionoida, Mycetopodidae

    Directory of Open Access Journals (Sweden)

    Luiz Ricardo L Simone

    1997-12-01

    Full Text Available The anatomy of Anodontiies elongatus (Swainson, 1823, a rare species restricted to the Amazon and Parana Basins, is described by first time, showing a group of conchological and anatomical characters exclusive of this species that may be analyzed to identify it. Diagnosis of A. elongatus: shell long antero-posteriorly, umbones prominent, periostracum opaque and smooth, two posterior radial striae; middle fold of mantle edge veiy tall; gill long antero-posteriorly and short dorso-ventrally, extending about a half of it total length beyond visceral mass; palps proportionally small, several furrows in its outer surface; stomach without esophageal transversal ridjp, dorsal hood and gastric shield poorly developed, major typhlosole entering in ddd , posterior pouch of sa³ very-long; style sac reduced, without crystalline style; distal region of intestine and rectum with a well developed typhlosole, "T" in section, other intestinal regions without folds; gonad gonochoristic.

  17. Opisthobranchia (Mollusca, Gastropoda – more than just slimy slugs. Shell reduction and its implications on defence and foraging

    Directory of Open Access Journals (Sweden)

    Wägele Heike

    2005-02-01

    Full Text Available Abstract Background In general shell-less slugs are considered to be slimy animals with a rather dull appearance and a pest to garden plants. But marine slugs usually are beautifully coloured animals belonging to the less-known Opisthobranchia. They are characterized by a large array of interesting biological phenomena, usually related to foraging and/or defence. In this paper our knowledge of shell reduction, correlated with the evolution of different defensive and foraging strategies is reviewed, and new results on histology of different glandular systems are included. Results Based on a phylogeny obtained by morphological and histological data, the parallel reduction of the shell within the different groups is outlined. Major food sources are given and glandular structures are described as possible defensive structures in the external epithelia, and as internal glands. Conclusion According to phylogenetic analyses, the reduction of the shell correlates with the evolution of defensive strategies. Many different kinds of defence structures, like cleptocnides, mantle dermal formations (MDFs, and acid glands, are only present in shell-less slugs. In several cases, it is not clear whether the defensive devices were a prerequisite for the reduction of the shell, or reduction occurred before. Reduction of the shell and acquisition of different defensive structures had an implication on exploration of new food sources and therefore likely enhanced adaptive radiation of several groups.

  18. Analysis of the first and second internal transcribed spacer sequences of the ribosomal DNA in Biomphalaria tenagophila complex (Mollusca: Planorbidae

    Directory of Open Access Journals (Sweden)

    Teofânia HDA Vidigal

    2004-03-01

    Full Text Available The first and second internal transcribed spacer regions (ITS1 and ITS2 of the ribosomal DNA of Biomphalaria tenagophila complex (B. tenagophila, B. occidentalis, and B. t. guaibensis were sequenced and compared. The alignment lengths of these regions were about 655 bp and 481 bp, respectively. Phylogenetic relationships among the Biomphalaria species were inferred by Maximum Parsimony and Neighbor-joining methods. The phylogenetic trees produced, in most of the cases, were in accordance with morphological systematics and other molecular data previously obtained by polymerase chain reaction and restriction fragment length polymorphism analysis. The present results provide support for the proposal that B. tenagophila represents a complex comprising B. tenagophila, B. occidentalis and B. t. guaibensis.

  19. Effects of endocrine disruptors on prosobranch snails (Mollusca: Gastropoda) in the laboratory. Part III: Cyproterone acetate and vinclozolin as antiandrogens.

    Science.gov (United States)

    Tillmann, M; Schulte-Oehlmann, U; Duft, M; Markert, B; Oehlmann, J

    2001-12-01

    The effects of suspected endocrine disrupting chemicals on freshwater and marine prosobranch species were analysed in laboratory experiments. In this last of three publications, the responses of the fresh water snail Marisa cornuarietis and of two marine prosobranchs (Nucella lapillus, Nassarius (Hinia) reticulatus) to the antiandrogenic model compounds cyproterone acetate (CPA) and vinclozolin (VZ) are presented. The snails were exposed to nominal CPA concentrations of 1.25 mg/L alone and simultaneously to a potent synthetic estrogen (ethinylestradiol), androgen (methyltestosterone) or an indirectly acting xeno-androgen (tributyltin) in experiments with adult specimens and in a life cycle test for 12 months. Marisa and Nucella were furthermore exposed to nominal concentrations of 0.03-1.0 microgram VZ/L for up to 5 months. The antiandrogens induced a number of biological responses in all three species. The length of the penis and of accessory male sex organs (e.g., penis sheath, prostate) were significantly reduced. For Marisa, this effect occurred only in sexually immature specimens and was reversible as the males attained puberty. Typical androgen-mediated responses (imposex development, delayed spermatogenesis, tubulus necrosis of the testis with orchitis and Leydig cell hyperplasia) were partially or totally suppressed by a simultaneous administration of CPA. In the two marine species even adult, sexually mature males responded to antiandrogens with a reduction of the male sex organs and an advancement of the sexual repose phase. The results for CPA and VZ are compared with the effects of an exposure to xeno-estrogens (bisphenol A, octylphenol) and xeno-androgens (triphenyltin, tributyltin) in the same species. Each group of endocrine disruptors induces a characteristic set of toxicological effects in prosobranch snails which can be used as endpoints in an organismic invertebrate test for the identification of endocrine mimetic test compounds. Estrogens cause primarily an induction of superfemales resulting in an increased female mortality by the enhancement of spawning mass and egg production. The main effects of androgens are a virilization of females by imposex development and a marked decrease of the fecundity. Compared with estrogens and androgens, the antiandrogen responses seem to be less drastic and might have--in contrast to the two other disruptor classes--no biologically significant effects at the population level.

  20. Effects of endocrine disruptors on prosobranch snails (Mollusca: Gastropoda) in the laboratory. Part II: Triphenyltin as a xeno-androgen.

    Science.gov (United States)

    Schulte-Oehlmann, U; Tillmann, M; Markert, B; Oehlmann, J; Watermann, B; Scherf, S

    2000-12-01

    In laboratory experiments the effects of suspected endocrine disrupting chemicals on freshwater and marine prosobranch species were analysed. In this second of three publications the responses of the freshwater ramshorn snail Marisa cornuarietis and of two marine prosobranchs (the dogwhelk Nucella lapillus and the netted whelk Hinia reticulata) to the xeno-androgenic model compound triphenyltin (TPT) are presented. Marisa and Nucella were exposed via water (nominal concentrations 5-500 ng TPT-Sn/L) and Hinia via sediments (nominal concentrations 50-500 micrograms TPT-Sn/kg dry wt.) for up to 4 months. Female ramshorn snails but not the two marine species developed imposex in a time and concentration dependent manner (EC10 4 months: 12.3 ng TPT-Sn/L) with a comparable intensity as described for tributyltin. TPT reduced furthermore the fecundity of Marisa at lower concentrations (EC10 4 months: 5.59 ng TPT-Sn/L) with a complete inhibition of spawning at nominal concentrations > or = 250 ng TPT-Sn/L (mean measured +/- SD: > or = 163 +/- 97.0 ng TPT-Sn/L). The extension of the pallial sex organs (penis with accessory structures and prostate gland) of male ramshorn snails and dogwhelks were reduced by up to 25% compared to the control but not in netted whelks. Histopathological analyses for M. cornuarietis and H. reticulata provide evidence for a marked impairment of spermatogenesis (both species) and oogenesis (only netted whelks). The test compound induced a highly significant and concentration independent increase in the incidence of hyperplasia on gills, osphradia and other organs in the mantle cavity of N. lapillus indicating a carcinogenic potential of TPT. The results show that prosobranchs are sensitive to endocrine disruption at environmentally relevant concentrations of TPT. Also, M. cornuarietis is a promising candidate for a future organismic invertebrate system to identify endocrine-mimetic test compounds.

  1. Inhibition of dye-coupling in Patella (mollusca) embryos by microinjection of antiserum against Nephrops (arthropoda) gap junctions

    NARCIS (Netherlands)

    Serras, F.; Buultjens, T.E.J.; Finbow, M.E.

    1988-01-01

    Antiserum raised against Nephrops gap junctions was injected into single cells of the 2-, 4-, 8-, 16-, and 32-cell stage of the Patella vulgata embryos. The pattern of junctional communication by iontophoresis of Lucifer Yellow CH was tested at the 32-cell stage. The results show that the normal

  2. Effect of temperature on growth, mortality, reproduction, and production of adult Lymnaea obrussa Say (Mollusca:Gastropoda)

    International Nuclear Information System (INIS)

    Mattice, J.S.

    1975-01-01

    Shell lengths and egg production were measured weekly under constant (K; 10, 15, 20, 25 0 C) and varying temperature regimes during the reproductive period. Varying regimes included natural field temperature in a pond (F; diurnal and seasonal), mean daily field temperature (anti F; seasonal) and 5 and 10 0 C above anti F. Growth rate of large snails (>10 mm) was unaffected by temperature, but small snails (6 to 10 mm) grew fastest at 15 0 C(K). Growth and reproductive periods were longest, production was highest, and mortality rate was lowest at 15 0 C(K). Rate (per snail) of egg production increased with temperature. At equal mean temperature, regime affected growth rate only at anti F. Regime affected the following values as shown: mortality rate,F > anti F = K; rate of reproduction, F > K > anti F; and total production, K > anti F = F. The validity of extrapolation of energetic data from laboratory to field is discussed. Data relating production and temperature are valuable in thermal impact analysis. (U.S.)

  3. Effect of heavy metals (Cu, Cd and Pb) on aspartate and alanine aminotransferase in Ruditapes philippinarum (Mollusca: Bivalvia)

    International Nuclear Information System (INIS)

    Blasco, J.; Puppo, J.

    1999-01-01

    The accumulation of cadmium, copper and lead and their effects on aspartate and alanine aminotransferases in digestive gland, gills, foot and soft body in the clam Ruditapes philippinarum were examined. The animals were exposed to different concentrations: Cd (200-600 μg·l -1 ), Pb (350-700 μg·l -1 ) and Cu (10-20 μg·l -1 ) for 7 days. The highest concentrations were found in digestive gland for cadmium and copper, and in gills for lead, and the lowest values were observed in the foot. Aspartate aminotransferase activity (AST), in general, was not inhibited by cadmium, lead or copper during the exposure. Only in clams exposed to cadmium (600 μg·l -1 , 7 days) and copper (20 μg·l -1 , 5 days) were observed significant differences (P -1 . A significant correlation (P<0.05) was observed between ALT and metal accumulation for cadmium, copper and lead in gills. In the case of soft body, only cadmium and lead showed a significant correlation. In summary, R. philippinarum can be considered a bioindicator species for cadmium and lead accumulation and ALT could be useful as biomarker of sublethal stress for these metals in soft tissues and gills. Only gills can be considered an adequate target tissue for copper. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Annotated type catalogue of the Bulimulidae (Mollusca, Gastropoda, Orthalicoidea in the Natural History Museum, London

    Directory of Open Access Journals (Sweden)

    Abraham Breure

    2014-03-01

    Full Text Available The type status is described of 404 taxa classified within the family Bulimulidae (superfamily Orthalicoidea and kept in the London museum. Lectotypes are designated for Bulimus aurifluus Pfeiffer, 1857; Otostomus bartletti H. Adams, 1867; Helix cactorum d’Orbigny, 1835; Bulimus caliginosus Reeve, 1849; Bulimus chemnitzioides Forbes, 1850; Bulimus cinereus Reeve, 1849; Helix cora d’Orbigny, 1835; Bulimus fallax Pfeiffer, 1853; Bulimus felix Pfeiffer, 1862; Bulimus fontainii d’Orbigny, 1838; Bulimus fourmiersi d’Orbigny, 1837; Bulimus (Mesembrinus gealei H. Adams, 1867; Bulimus gruneri Pfeiffer, 1846; Bulimus humboldtii Reeve, 1849; Helix hygrohylaea d’Orbigny, 1835; Bulimus jussieui Pfeiffer, 1846; Bulimulus (Drymaeus binominis lascellianus E.A. Smith, 1895; Helix lichnorum d’Orbigny, 1835; Bulimulus (Drymaeus lucidus da Costa, 1898; Bulimus luridus Pfeiffer, 1863; Bulimus meleagris Pfeiffer, 1853; Bulimus monachus Pfeiffer, 1857; Bulimus montagnei d’Orbigny, 1837; Helix montivaga d’Orbigny, 1835; Bulimus muliebris Reeve, 1849; Bulimus nigrofasciatus Pfeiffer in Philippi 1846; Bulimus nitelinus Reeve, 1849; Helix oreades d’Orbigny, 1835; Helix polymorpha d’Orbigny, 1835; Bulimus praetextus Reeve, 1849; Bulinus proteus Broderip, 1832; Bulimus rusticellus Morelet, 1860; Helix sporadica d’Orbigny, 1835; Bulimus sulphureus Pfeiffer, 1857; Helix thamnoica var. marmorata d’Orbigny, 1835; Bulinus translucens Broderip in Broderip and Sowerby I 1832; Helix trichoda d’Orbigny, 1835; Bulinus ustulatus Sowerby I, 1833; Bulimus voithianus Pfeiffer, 1847; Bulimus yungasensis d’Orbigny, 1837.The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Bulimulus (Drymaeus caucaensis da Costa, 1898; Drymaeus exoticus da Costa, 1901; Bulimulus (Drymaeus hidalgoi da Costa, 1898; Bulimulus (Drymaeus interruptus Preston, 1909; Bulimulus (Drymaeus inusitatus Fulton, 1900; Bulimulus latecolumellaris Preston, 1909; Bulimus (Otostomus napo Angas, 1878; Drymaeus notabilis da Costa, 1906; Drymaeus notatus da Costa, 1906; Bulimulus (Drymaeus nubilus Preston, 1903; Drymaeus obliquistriatus da Costa, 1901; Bulimus (Drymaeus ochrocheilus E.A. Smith, 1877; Bulimus (Drymaeus orthostoma E.A. Smith, 1877; Drymaeus expansus perenensis da Costa, 1901; Bulimulus pergracilis Rolle, 1904; Bulimulus (Drymaeus plicatoliratus da Costa, 1898; Drymaeus prestoni da Costa, 1906; Drymaeus punctatus da Costa, 1907; Bulimus (Leptomerus sanctaeluciae E.A. Smith, 1889; Bulimulus (Drymaeus selli Preston, 1909; Drymaeus subventricosus da Costa, 1901; Bulimulus ( Drymaeus tigrinus da Costa, 1898; Drymaeus volsus Fulton, 1907; Drymaeus wintlei Finch, 1929; Bulimus zhorquinensis Angas, 1879; Bulimulus (Drymaeus ziczac da Costa, 1898.The following junior subjective synonyms are established: Bulimus antioquensis Pfeiffer, 1855 = Bulimus baranguillanus Pfeiffer, 1853; Drymaeus bellus da Costa, 1906 = Drymaeus blandi Pilsbry, 1897; Bulimus hachensis Reeve 1850 = Bulimus gruneri Pfeiffer, 1846 = Bulimus columbianus Lea, 1838; Bulimus (Otostomus lamas Higgins 1868 = Bulimus trujillensis Philippi, 1867; Bulimulus (Drymaeus binominis lascellianus E.A. Smith, 1895 = Bulimulus (Drymaeus binominis E.A. Smith, 1895; Drymaeus multispira da Costa, 1904 = Helix torallyi d’Orbigny, 1835; Bulimulus (Drymaeus plicatoliratus Da Costa, 1898 = Bulimus convexus Pfeiffer, 1855; Bulimus sugillatus Pfeiffer, 1857 = Bulimus rivasii d’Orbigny, 1837; Bulimus meridionalis Reeve 1848 [June] = Bulimus voithianus Pfeiffer, 1847.New combinations are: Bostryx montagnei (d’Orbigny, 1837; Bostryx obliquiportus (da Costa, 1901; Bulimulus heloicus (d’Orbigny, 1835; Drymaeus (Drymaeus lusorius (Pfeiffer, 1855; Drymaeus (Drymaeus trigonostomus (Jonas, 1844; Drymaeus (Drymaeus wintlei Finch, 1929; Drymaeus (Mesembrinus conicus da Costa, 1907; Kuschelenia (Kuschelenia culminea culminea (d’Orbigny, 1835; Kuschelenia (K. culmineus edwardsi (Morelet, 1863; Kuschelenia (K. gayi (Pfeiffer, 1857; Kuschelenia (K. tupacii (d’Orbigny, 1835; Kuschelenia (Vermiculatus anthisanensis (Pfeiffer, 1853; Kuschelenia (Vermiculatus aquilus (Reeve, 1848; Kuschelenia (Vermiculatus bicolor (Sowerby I, 1835; Kuschelenia (Vermiculatus caliginosus (Reeve, 1849; Kuschelenia (Vermiculatus cotopaxiensis (Pfeiffer, 1853; Kuschelenia (Vermiculatus filaris (Pfeiffer, 1853; Kuschelenia (Vermiculatus ochracea (Morelet, 1863; Kuschelenia (Vermiculatus petiti (Pfeiffer, 1846; Kuschelenia (Vermiculatus purpuratus (Reeve, 1849; Kuschelenia (Vermiculatus quechuarum (Crawford, 1939; Naesiotus cinereus (Reeve, 1849; Naesiotus dentritis (Morelet, 1863; Naesiotus fontainii (d’Orbigny, 1838; Naesiotus orbignyi (Pfeiffer, 1846; Protoglyptus pilosus (Guppy, 1871; Protoglyptus sanctaeluciae (E.A. Smith, 1889.Type material of the following taxa is figured herein for the first time: Bulimus cinereus Reeve, 1849; Bulimus coriaceus Pfeiffer, 1857; Bulimulus laxostylus Rolle, 1904; Bulimus pliculatus Pfeiffer, 1857; Bulimus simpliculus Pfeiffer, 1855.

  5. Crecimiento y mortalidad de Pinctada imbricata (Mollusca: Pteridae en Guamachito, Península de Araya, Estado Sucre, Venezuela

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available Se analizó el crecimiento, la distribución de tallas y la mortalidad de una población de Pinctada imbricata en Guamachito, Península de Araya, Venezuela, entre enero y diciembre de 2000. Los muestreos se realizaron mensualmente sobre transeptos perpendiculares a la línea de la costa con una rastra artesanal, tomando también datos sobre temperatura, oxígeno disuelto y salinidad de la columna de agua. La distribución de tallas fue variable con un predominio de tallas entre 50 y 70 mm, que constituyeron el 75% de la población. La mayor cantidad de juveniles fue observada en marzo, cuando la longitud media en la población fue de 55.8 mm. Los promedios de los pesos húmedo y seco siguieron la misma tendencia, con valores mínimos en junio, julio, septiembre y octubre de 2000. Las relaciones longitud-peso húmedo y longitud-peso seco fueron altamente significativas (P < 0.05. Los parámetros de la ecuación de crecimiento estacionalizada de von Bertalanffy fueron L∞ = 85.15 mm; K = 1.42 año–1, ts = 0.2, y C = 0.20; indicando un crecimiento lento (WP = 0.42 en el periodo de julio a noviembre, asociado con los parámetros ambientales del área con una longevidad estimada en 3 años. La mortalidad total fue de 14.35 año para los individuos pequeños (10–36 mm y 3.45 año, para los individuos grandes (36–84 mm. La alta tasa de crecimiento de P. imbricata muestra ser una ventaja para considerarla como una especie con potencial para actividades de acuicultura en la región. El banco ostrícola presenta buenas condiciones para mantener una explotación pesquera sostenida, tomando en consideración parámetros pesqueros como la captura registrada, el esfuerzo óptimo, la talla mínima de extracción, la mortalidad por pesca y la mortalidad natural.

  6. A high molecular weight proteoglycan is differentially expressed during development of the mollusc Concholepas concholepas (Mollusca; Gastropoda; Muricidae).

    Science.gov (United States)

    Brandan, E; González, M; Inestrosa, N C; Tremblay, C; Urrea, R

    1992-12-15

    Incorporation of radioactive sulfate to hatched veliger larvae of the gastropod muricid Concholepas concholepas indicated that over 87% of the sulfated macromolecules were found in the detergent insoluble fraction, rich in extracellular matrix (ECM) components. The sulfated material was solubilized with guanidine salt followed by urea dialysis and fractionated by DEAE-Sephacel chromatography. Three sulfated compounds eluting at 0.7, 1.1, and 3.0 M NaCl, called peaks I, II, and III, respectively, were obtained. The sulfated compound present in peak I was degraded by pronase or sodium alkaline treatment to a small sulfated resistant material, suggesting the presence of a proteoglycan (PG). Filtration analysis on Sephacryl S-500 and SDS-PAGE of the intact PG indicates that it has a high molecular weight (360,000 to over 1 x 10(6)). Monoclonal antibodies (mAb) against this PG were produced. The specificity of one mAb, the 6H2, was demonstrated by size chromatography and ELISA analysis. The epitope recognized by this mAb seems to be present in the core protein of the PG. Both the extent of sulfation and the presence of different sulfated species of PGs were evaluated during the development of this mollusc. A twelvefold increase in the incorporation of sulfate to PGs per milligram of protein was found in veliger larvae compared to blastula-glastula stages. This change correlated well with the differential expression of the sulfated PG present in peak I. Biochemical and immunological analysis indicate that high levels of this PG are found in veliger and trocophore larvae in comparison with blastula-gastrula and early juveniles.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Ecotoxicological studies with newly hatched larvae of Concholepas concholepas (Mollusca, Gastropoda): bioassay with secondary-treated kraft pulp mill effluents.

    Science.gov (United States)

    Manríquez, Patricio H; Llanos-Rivera, Alejandra; Galaz, Sylvana; Camaño, Andrés

    2013-12-01

    The Chilean abalone or "loco" (Concholepas concholepas, Bruguière 1789) represent the most economically important marine recourse exploited from inner inshore Management and Exploitation Areas for Benthic Resources along the Chilean coast. In this study, newly-hatched larvae of C. concholepas were investigated as a potential model species for marine ecotoxicological studies. The study developed a behavioral standard protocol for assessing the impact that kraft pulp mill effluents after secondary treatment have on C. concholepas larvae. Under controlled laboratory conditions, newly-hatched larvae were exposed to a series of different concentrations of kraft pulp mill effluents with secondary treatment (Pinus spp. and Eucalyptus spp.), potassium dichromate as standard reference toxicant and effluent-free control conditions. Regardless of the type of effluent the results indicated that diluted kraft pulp effluent with secondary treatment had reduced effect on larval survival. Low larval survivals were only recorded when they were exposed to high concentrations of the reference toxicant. This suggests that C. concholepas larval bioassay is a simple method for monitoring the effects of kraft pulp mill effluents with secondary treatment discharged into the sea. The results indicated that dilution of ca. 1% of the effluent with an elemental chlorine free (ECF) secondary treatment is appropriate for achieving low larval mortalities, such as those obtained under control conditions with filtered seawater, and to minimize their impact on early ontogenetic stages of marine invertebrates such as newly-hatched larvae of C. concholepas. The methodological aspects of toxicological testing and behavioral responses described here with newly-hatched larvae of C. concholepas can be used to evaluate in the future the potential effects of other stressful conditions as other pollutants or changes in seawater pH associated with ocean acidification. © 2013 Elsevier Inc. All rights reserved.

  8. Cytogenetic characterisation of the razor shells Ensis directus (Conrad, 1843) and E. minor (Chenu, 1843) (Mollusca: Bivalvia)

    Science.gov (United States)

    González-Tizón, Ana M.; Rojo, Verónica; Vierna, Joaquín; Jensen, K. Thomas; Egea, Emilie; Martínez-Lage, Andrés

    2013-03-01

    The European razor shell Ensis minor (Chenu 1843) and the American E. directus (Conrad 1843) have a diploid chromosome number of 38 and remarkable differences in their karyotypes: E. minor has four metacentric, one metacentric-submetacentric, five submetacentric, one subtelocentric and eight telocentric chromosome pairs, whereas E. directus has three metacentric, two metacentric-submetacentric, six submetacentric, six subtelocentric and two telocentric pairs. Fluorescent in situ hybridisation (FISH) using a major ribosomal DNA probe located the major ribosomal genes on one submetacentric chromosome pair in both species; FISH with a 5S ribosomal DNA (5S rDNA) probe rendered one chromosomal (weak) signal for E. minor and no signal for E. directus, supporting a more dispersed organisation of 5S rDNA compared to the major ribosomal genes. The vertebrate telomeric sequence (TTAGGG) n was located on both ends of each chromosome, and no interstitial signals were detected. In this work, a comparative karyological analysis was also performed between the four Ensis species analysed revealing that the three European species studied so far, namely E. minor, E. siliqua (Linné 1758) and E. magnus Schumacher 1817 show more similarities among them than compared to the American species E. directus. In addition, clear karyotype differences were found between the morphologically similar species E. minor and E. siliqua.

  9. Molecular discrimination of Perna (Mollusca: Bivalvia) species using the polymerase chain reaction and species-specific mitochondrial primers

    DEFF Research Database (Denmark)

    Blair, D.; Waycott, M.; Byrne, L.

    2006-01-01

    This work was prompted by the need to be able to identify the invasive mussel species, Perna viridis, in tropical Australian seas using techniques that do not rely solely on morphology. DNA-based molecular methods utilizing a polymerase chain reaction (PCR) approach were developed to distinguish...

  10. A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina

    Science.gov (United States)

    Liew, Thor-Seng; Vermeulen, Jaap Jan; Marzuki, Mohammad Effendi bin; Schilthuizen, Menno

    2014-01-01

    Abstract Plectostoma is a micro land snail restricted to limestone outcrops in Southeast Asia. Plectostoma was previously classified as a subgenus of Opisthostoma because of the deviation from regular coiling in many species in both taxa. This paper is the first of a two-part revision of the genus Plectostoma, and includes all non-Borneo species. In the present paper, we examined 214 collection samples of 31 species, and obtained 62 references, 290 pictures, and 155 3D-models of 29 Plectostoma species and 51 COI sequences of 19 species. To work with such a variety of taxonomic data, and then to represent it in an integrated, scaleable and accessible manner, we adopted up-to-date cybertaxonomic tools. All the taxonomic information, such as references, classification, species descriptions, specimen images, genetic data, and distribution data, were tagged and linked with cyber tools and web servers (e.g. Lifedesks, Google Earth, and Barcoding of Life Database). We elevated Plectostoma from subgenus to genus level based on morphological, ecological and genetic evidence. We revised the existing 21 Plectostoma species and described 10 new species, namely, P. dindingensis sp. n., P. mengaburensis sp. n., P. whitteni sp. n., P. kayiani sp. n., P. davisoni sp. n., P. relauensis sp. n., P. kubuensis sp. n., P. tohchinyawi sp. n., P. tenggekensis sp. n., and P. ikanensis sp. n. All the synthesised, semantic-tagged, and linked taxonomic information is made freely and publicly available online. PMID:24715783

  11. On growth and form of irregular coiled-shell of a terrestrial snail: Plectostoma concinnum (Fulton, 1901 (Mollusca: Caenogastropoda: Diplommatinidae

    Directory of Open Access Journals (Sweden)

    Thor-Seng Liew

    2014-05-01

    Full Text Available The molluscan shell can be viewed as a petrified representation of the organism’s ontogeny and thus can be used as a record of changes in form during growth. However, little empirical data is available on the actual growth and form of shells, as these are hard to quantify and examine simultaneously. To address these issues, we studied the growth and form of a land snail that has an irregularly coiled and heavily ornamented shell–Plectostoma concinnum. The growth data were collected in a natural growth experiment and the actual form changes of the aperture during shell ontogeny were quantified. We used an ontogeny axis that allows data of growth and form to be analysed simultaneously. Then, we examined the association between the growth and the form during three different whorl growing phases, namely, the regular coiled spire phase, the transitional constriction phase, and the distortedly-coiled tuba phase. In addition, we also explored the association between growth rate and the switching between whorl growing mode and rib growing mode. As a result, we show how the changes in the aperture ontogeny profiles in terms of aperture shape, size and growth trajectory, and the changes in growth rates, are associated with the different shell forms at different parts of the shell ontogeny. These associations suggest plausible constraints that underlie the three different shell ontogeny phases and the two different growth modes. We found that the mechanism behind the irregularly coiled-shell is the rotational changes of the animal’s body and mantle edge with respect to the previously secreted shell. Overall, we propose that future study should focus on the role of the mantle and the columellar muscular system in the determination of shell form.

  12. Aspects of the biology of Mya arenaria and Ensis spp. (Mollusca; Bivalvia) in the Irish Sea and adjacent areas

    OpenAIRE

    Cross, Maud E.

    2014-01-01

    This study was undertaken to investigate the general biology, including the reproductive cycle and health status, of two clam taxa in Irish waters, with particular reference to the Irish Sea area. Monthly samples of the soft shell clam, Mya arenaria, were collected from Bannow Bay, Co. Wexford, Ireland, for sixteen months, and of the razor clam, Ensis spp. from the Skerries region (Irish Sea) between June 2010 and September 2011. In 2010, M. arenaria in Bannow Bay matured over the summer mont...

  13. The Effects of Mercury Exposure on the Surface Morphology of Gill Filaments in Perna perna (Mollusca: Bivalvia)

    International Nuclear Information System (INIS)

    Gregory, M.A.; George, R.C.; Marshall, D.J.; Anandraj, A.; McClurg, T.P.

    1999-01-01

    This study investigated the possibility that changes in the surface morphology of mussel (Perna perna) gill filaments may be used to indicate the relative toxicity of pollutants in the marine environment. Healthy, adult P. perna were collected and immersed in 2 free-flow tanks. Mercury was added to seawater as it entered tank 1 to achieve a constant level of 50 μg/l -1 over 24 days. Uncontaminated seawater was circulated over the mussels in tank 2 (control) for the same period. A 25 mm 2 area of gill filament was removed from each of the 5 specimens before and after 24 days immersion in tank 2, and after immersion for 1, 2, 4, 8, 16 and 24 days in tank 1. These were examined using a scanning electron microscope. The remaining soft tissues from each animal were analysed for mercury using an atomic absorption spectrometer. Mercury concentration increased from 0.13 (pre-immersion) to 87 μg/g after day 24. Surface morphology remained normal for all animals in tank 2 and for those exposed to Hg for up to 8 days. However, from 16 to 24 days exposure there was a gradual increase in the diameters of microvilli, a depletion of abfrontal cilia, an increase in abnormal, perhaps necrotic cells and an unusual increase in the number of cilia on the lateral surfaces. These results confirm that P. perna is an efficient bio-accumulator and suggest that their gill pathomorphology may be a useful indicator of toxicity

  14. Cutaneous application of an accessory-gland secretion after sperm exchange in a terrestrial slug (Mollusca : Pulmonata)

    NARCIS (Netherlands)

    Benke, Mandy; Reise, Heike; Montagne-Wajer, Kora; Koene, Joris M

    Competition for fertilisation in hermaphroditic animals seems to have led to many odd behaviours and complex morphologies involved in the transfer of accessory-gland products to the partner. Terrestrial slugs of the genus Deroceras show remarkably elaborate and interspecifically diverse penis

  15. Putative midkine family protein up-regulation in Patella caerulea (Mollusca, Gastropoda) exposed to sublethal concentrations of cadmium

    International Nuclear Information System (INIS)

    Vanucci, Silvana; Minerdi, Daniela; Kadomatsu, Kenji; Mengoni, Alessio; Bazzicalupo, Marco

    2005-01-01

    A cDNA sequence of a putative midkine (MK) family protein was identified and characterised in the mollusc Patella caerulea. The midkine family consists of two members, midkine and pleiotrophin (PTN), and it is one of the recently discovered cytokines. Our results show that this putative midkine protein is up-regulated in specimens of P. caerulea exposed to sublethal cadmium concentrations (i.e. 0.5 and 1 mg l -1 Cd) over a 10-day exposure period. Semiquantitative RT-PCR and quantitative Real time RT-PCR estimations indicate elevated expression of midkine mRNA in exposed specimens compared to controls. Moreover, RT-PCR Real time values were higher in the viscera (here defined as the part of the soft tissue including digestive gland plus gills) than in the foot (i.e. foot plus head plus heart) of the limpets. At present, information on the functional signalling significance of the midkine family proteins suggests that the up-regulation of P. caerulea putative midkine family protein is a distress signal likely with informative value on health status of the organism and with potential prognostic capability

  16. Evidencia de dispersión de semillas de Sterculia apetala (Jacq. Karst. por Ramphastos toco (Muller 1776, en la región del Pantanal / Evidence of Seed Dispersion in Sterculia apetala (Jacq. Karst. by Rampahstos toco (Muller 1776, in The Pantanal Region

    Directory of Open Access Journals (Sweden)

    Antônio dos Santos Júnior

    2006-08-01

    Full Text Available El comportamiento de alimentación del Ramphastos toco en frutas del Sterculia apetala fue observado en la Estancia Caiman (19°51’ 05” S - 56°16’ 10” W, Miranda - MS, en el Medio oeste de Brasil. El R. toco es un visitante frecuente de las frutas del S. apetala en busca de sus semillas nutritivas. El pájaro ingiere las semillas enteras, quita la sarcotesta que cubre las semillas y comienza a regurgitar las semillas enteras y intactas. Esta información sugiere que el R. toco sea un dispersor potencial de semillas de S. apetala, aunque investigaciones acerca de la germinación de semillas regurgitadas sean necesarias para explicar si el R. toco es un dispersor efectivo del S. apetala en el Pantanal.

  17. Evidencia de dispersión de semillas de Sterculia apetala (Jacq.) Karst. por Ramphastos toco (Muller 1776), en la región del PantanalEvidence of Seed Dispersion in Sterculia apetala (Jacq.) Karst. by Rampahstos toco (Muller 1776), in The Pantanal Region

    OpenAIRE

    Santos Júnior, Antônio dos

    2009-01-01

    ResumenEl comportamiento de alimentación del Ramphastos toco en frutas del Sterculia apetala fue observado en la Estancia Caiman (19°51’ 05” S - 56°16’ 10” W), Miranda - MS, en el Medio oeste de Brasil. El R. toco es un visitante frecuente de las frutas del S. apetala en busca de sus semillas nutritivas. El pájaro ingiere las semillas enteras, quita la sarcotesta que cubre las semillas y comienza a regurgitar las semillas enteras y intactas. Esta información sugiere que el R. toco sea un disp...

  18. Individual based model of slug population and spatial dynamics

    NARCIS (Netherlands)

    Choi, Y.H.; Bohan, D.A.; Potting, R.P.J.; Semenov, M.A.; Glen, D.M.

    2006-01-01

    The slug, Deroceras reticulatum, is one of the most important pests of agricultural and horticultural crops in UK and Europe. In this paper, a spatially explicit individual based model (IbM) is developed to study the dynamics of a population of D. reticulatum. The IbM establishes a virtual field

  19. Evaluation of California isolates of Lingulodinium polyedrum for the ...

    African Journals Online (AJOL)

    Yessotoxin (YTX) is a newly discovered type of phycotoxin that is commonly produced by two dinoflagellates, Protoceratium reticulatum and Lingulodinium polyedrum. P. reticulatum has been confirmed to produce YTX and other analogues from isolates in New Zealand, Norway, Spain, Italy, Canada, the United Kingdom ...

  20. Bayero Journal of Pure and Applied Sciences - Vol 8, No 1 (2015)

    African Journals Online (AJOL)

    ... metals to Vigna unguiculata l (beans) grown on crude oil contaminated soil · EMAIL ... niloticus) fed on diets containing watermelon (Citrullus lanatus) seedmeal ... methods on the proximate composition of Piliostegma reticulatum seed meal ...

  1. Emergence, development, and maturity of the gonad of two species of chitons "sea cockroach" (Mollusca: Polyplacophora) through the early life stages.

    Science.gov (United States)

    Avila-Poveda, Omar Hernando; Abadia-Chanona, Quetzalli Yasú

    2013-01-01

    This study describes and recognises, using histological and microscopical examinations on a morphometrical basis, several gonad traits through the early life stages of Chiton articulatus and C. albolineatus. Gonadal ontogenesis, gonad development stages, sexual differentiation, onset of the first sexual maturity, and growth sequences or "early life stages" were determined. In addition, allometry between lengths and body weight pooled for both sexes per each chiton were calculated using equation Y = aX(b) . A total of 125 chitons (4≤TL≤40 mm, in total length "TL") were used. All allometric relations showed a strong positive correlation (r), close to 1, with b-values above three, indicating an isometric growth. Gonadal ontogenesis and gonad development stages were categorised into three periods ("Pw" without gonad, "Pe" gonad emergence, and "Pf" gonadal sac formed) and four stages ("S0" gametocytogenesis, "S1" gametogenesis, "S2" mature, and "S3" spawning), respectively. Compound digital images were attained for each process. Periods and stages are overlapped among them and between species, with the following overall confidence intervals in TL: Pw 6.13-14.32 mm, Pe 10.32-16.93 mm, Pf 12.99-25.01 mm, S0 16.08-24.34 mm (females) and 19.51-26.60 mm (males), S1 27.15-35.63 mm (females) and 23.45-32.27 mm (males), S2 24.48-40.24 mm (females) and 25.45-32.87 mm (males). Sexual differentiation (in S0) of both chitons occurs first as a female then as a male; although, males reach the onset of the first sexual maturity earlier than females, thus for C. articulatus males at 17 mm and females at 32 mm, and for C. albolineatus males at 23.5 mm and females at 28 mm, all in TL. Four early life stages (i.e., subjuvenile, juvenile, subadult, and adult) are described and proposed to distinguish growth sequences. Our results may be useful to diverse disciplines, from developmental biology to fisheries management.

  2. Toxicological perspective on the osmoregulation and ionoregulation physiology of major ions by freshwater animals: Teleost fish, crustacea, aquatic insects, and Mollusca.

    Science.gov (United States)

    Griffith, Michael B

    2017-03-01

    Anthropogenic sources increase freshwater salinity and produce differences in constituent ions compared with natural waters. Moreover, ions differ in physiological roles and concentrations in intracellular and extracellular fluids. Four freshwater taxa groups are compared, to investigate similarities and differences in ion transport processes and what ion transport mechanisms suggest about the toxicity of these or other ions in freshwater. Although differences exist, many ion transporters are functionally similar and may belong to evolutionarily conserved protein families. For example, the Na + /H + -exchanger in teleost fish differs from the H + /2Na + (or Ca 2+ )-exchanger in crustaceans. In osmoregulation, Na + and Cl - predominate. Stenohaline freshwater animals hyperregulate until they are no longer able to maintain hypertonic extracellular Na + and Cl - concentrations with increasing salinity and become isotonic. Toxic effects of K + are related to ionoregulation and volume regulation. The ionic balance between intracellular and extracellular fluids is maintained by Na + /K + -adenosine triphosphatase (ATPase), but details are lacking on apical K + transporters. Elevated H + affects the maintenance of internal Na + by Na + /H + exchange; elevated HCO 3 - inhibits Cl - uptake. The uptake of Mg 2+ occurs by the gills or intestine, but details are lacking on Mg 2+ transporters. In unionid gills, SO 4 2- is actively transported, but most epithelia are generally impermeant to SO 4 2- . Transporters of Ca 2+ maintain homeostasis of dissolved Ca 2+ . More integration of physiology with toxicology is needed to fully understand freshwater ion effects. Environ Toxicol Chem 2017;36:576-600. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

  3. Los moluscos terrestres (Mollusca: Gastropoda de Costa Rica: clasificación, distribución y conservación

    Directory of Open Access Journals (Sweden)

    Zaidett Barrientos Llosa

    2010-12-01

    Full Text Available Los moluscos terrestres son un grupo muy poco estudiado a nivel mundial. Hay 183 especies reportadas para Costa Rica, 30% son endémicas y 7% posiblemente están extintas. Se espera que en el país haya alrededor de 400 especies, de más del 95% se desconoce su biología, ecología, distribución, genética y otros campos de estudio. En Costa Rica las familias con mayor número de especies son Spiraxidae, Orthalicidae y Subulinidae. No obstante, es posible que Euconulidae sea aun más diversa, pues habitan las zonas altas del país que es en donde menos trabajo se ha hecho. El estudio de regiones altas aumentará el porcentaje de endemismo. Los futuros trabajos malacológicos taxonómicos, biológicos y ecológicos deben considerar la poca movilidad de este grupo, su tendencia a formar especies nuevas en simpatría, la especificidad de requerimientos de microhábitat, el hermafroditismo, la alta tasa de evolución (10% por millón de años y la divergencia entre especies (2-30%. Para proteger adecuadamente la biodiversidad de la malacofauna costarricense, se requiere de estudios que determinen la distribución y abundancia de las especies y el efecto del uso de la tierra y del climático.

  4. On the identities of the molluscan names described in A Short Zoology of Tahiti in the Society Islands by Anthony Curtiss in 1938 (Mollusca: Cephalopoda, Gastropoda).

    Science.gov (United States)

    Low, Martyn E Y; Tan, Siong Kiat

    2014-02-11

    Anthony Curtiss described two species of cephalopod and nine species of gastropod molluscs from Tahiti. Herein, we discuss and determine the identities of these eleven names. Ten of these names are considered to be junior subjective synonyms of well-known taxa, and one an unavailable name.

  5. Distribución del género Diplodon (Mollusca: Bivalvia: Hyriidae en territorio Argentino mediante el uso de Colecciones Biológicas

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    Santiago Hernán Torres

    2013-10-01

    Full Text Available Los bivalvos nacaríferos dulciacuícolas (“náyades”, son especies infaunales, endémicas de la RegiónNeotropical, pertenecientes a las familias Hyriidae (Swaison, 1840 y Etheriidae (Swaison, 1840. La alteración del ambiente y la competencia con especies invasoras como Corbicula fluminea (Müller, 1774 y Limnoperna fortunei (Dunker, 1857, impactan sobre las poblaciones naturales. En esta comunicación, se presenta el inicio de un Proyecto de investigación sobre la distribución geográfica de las especies del género Diplodon en la Argentina. Estas especies son un componente importante de la infauna de los cuerpos lóticos y lénticos, viviendo en fondos limosos, limo-arenosos, excepcionalmente en sustratos duros, con un régimen nutricio filtrador, teniendo un papel importante como recicladores de materia orgánica. Conocer la distribución de los bivalvos pertenecientes al género Diplodon en el territorio Argentino permitirá el reconocimiento de potenciales áreas prioritarias para su conservación. Sobre la base de la bibliografía disponible y los ejemplares de las especies del genero Diplodon depositados en la Colección Malacológica del Museo de La Plata (FCNyM-UNLP, se confeccionó una matriz de datos que incluye la identificación del ejemplar, la colección en que se encuentra depositado, el número de catálogo, la localidad y la fecha de colecta. Cada localidad fue ubicada mediante el uso de cartas geográficas de Argentina y revisiones bibliográficas en imágenes satelitales de GoogleEarth, asignando las coordenadas para cada punto. Como resultado del trabajo se obtiene la distribución de estas especies nativas y se discute el grado de solapamiento con las dos especies de bivalvos invasores y el impacto de actividades humanas. 

  6. Nueva especie de Planorbidae (Gastropoda: Basommatophora en la Patagonia chilena: Biomphalaria cristiani sp. nov. First record of Planorbidae (Mollusca: Basommatophora in Chilean Patagonia: Biomphalaria cristiani sp. nov.

    Directory of Open Access Journals (Sweden)

    Carmen Fuentealba

    2012-11-01

    Full Text Available En Chile la familia Planorbidae está representada por el género Biomphalaria Preston, 1910, compuesta por siete especies distribuidas desde Isluga hasta el río Puelo. De estas especies, solo B.peregrina, ampliamente distribuida en el neotrópico, y Biomphalaria aymara de Isluga, han sido reconocidas sobre la base de la morfología del sistema reproductor y la rádula, caracteres que fueron utilizados en el presente estudio para diferenciar a Biomphalaria cristiani como nueva especie del grupo y primer registro de la familia en la Patagonia chilena, ampliando su actual rango de distribución. Los caracteres que permiten la diagnosis de B. cristiani son el saco vaginal vestigial truncado, ausencia del desarrollo de los músculos suspensores del pene, vaina del pene corta en relación al prepucio, oviducto largo en relación al espermioducto y vaso deferente más delgado y largo que la vaina del pene, de tamano similar al prepucio. La localidad tipo de Biomphalaria cristiani sp. nov. es Laguna Cisnes (47°7'10.02"S, 72°27'40.65"W, región de Aysén.The family Planorbidae in Chile is represented by the genus Biomphalaria Preston, 1910, consisting of seven species distributed from Isluga to Puelo River. Of these species, only Biomphalaria peregrina widely distributed in the neotropical and Biomphalaria aymara from Isluga are recognized based on the morphology of the reproductive system and radula, characters that were used in the following study to differentiate Biomphalaria cristiani as a new species of this group and first record of the family in Chilean Patagonia, extending its current distribution range. The characters for the diagnosis of B. cristiani are: truncated vestigial vaginal pouch, lack of development of the penis retractor muscles, penis sheath shorter than the prepuce, oviduct longer than the spermiduct and vas deferens thinner and longer than the penis sheath, similar size to the prepuce. The type locality of B. cristiani nov. sp. is Laguna Cisnes (47°7'10.02"S; 72°27'40.65"W, Aysén region.

  7. Observations on the symbiosis between Colus gracilis (Da Costa, 1778) (Mollusca: Gastropoda) and Hormathia digitata (O.F. Müller, 1776) (Cnidaria: Actiniaria)

    NARCIS (Netherlands)

    Ates, R.M.L.

    1998-01-01

    Aquarium observations of the behaviour of the actinian Hormathia digitata when mounting live specimens of the gastropod Colus gracilis are fully described for the first time. C. gracilis actively initiates an association with H. digitata by approaching and remaining stationary near the actinian.

  8. Reproductive activity and biochemical composition of the pullet carpet shell Venerupis senegalensis (Gmelin, 1791 (Mollusca: Bivalvia from Ria de Aveiro (northwestern coast of Portugal

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    Sandra Joaquim

    2011-06-01

    Full Text Available The present study characterizes the reproductive cycle of Venerupis senegalensis (=V. pullastra from Ria de Aveiro (Portugal as well as its nutrient storage and exploitation strategy. The reproductive cycle followed a seasonal cycle that correlated negatively with sea surface temperature, and comprised a ripe stage in winter followed by a spawning period that began in late winter and ended in the early summer. This extended spawning may be an advantageous strategy for the species because it ensures a continuous supply of settlers. Gametogenesis began in late summer/early autumn and intensified with the decrease in temperature during autumn. The condition index increased even during the spawning period, which indicates that there is rapid recovery and that reserves are accumulated during late summer and used later in the gametogenic process. Proteins did not contribute significantly to gametogenesis and the glycogen pattern is typical of conservative species, since gametogenesis depends largely on the amount of glycogen stored. The lipid storage and utilization cycle showed that gametogenesis took place in autumn/winter and that energy reserves were accumulated in summer.

  9. The population density of Lymnaea columella (Say, 1817) (Mollusca, Lymnaeidae) an intermediate host of Fasciola hepatica (Linnaeus, 1758), in the Caparaó microregion, ES, Brazil.

    Science.gov (United States)

    D'Almeida, S C G; Freitas, D F; Carneiro, M B; Camargo, P F; Azevedo, J C; Martins, I V F

    2016-06-01

    The aim of this study was to monitor the population density of Lymnaea columella, an intermediate host of Fasciola hepatica, in various aquatic habitats and in drinking water in the area of the Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, on Caparaó Microregion, municipality of Alegre, state of Espírito Santo, Brazil. Monthly samplings were performed at certain points between drainage areas and drinking water in cattle and goat production systems during the years 2010 to 2013. The mean temperature, precipitation and the frequency of samples of L. columella were analysed graphically according the monthly average during the study period. A total of 2,038 molluscs were collected, 1558 of which were L. columella, that predominated in all sampled points. The highest average of specimens observed for L. columella was in the years 2010 and 2013 (51.0), and occurred decreased in 2011 (19.8). The temperature and precipitation averaged is 23.7 °C and 141 mm/year, respectively. Rainfall peak occurred in March (2011, 2013) and November (2012), during these periods the population of L. columella growth. There was no significant difference in the relationship between the specimens observed with seasons (dry-wet), thus the population of L. columella remained stable and can be found throughout the year.

  10. Evaluation of magnesium and manganese in Perna perna mussels (Linnaeus, 1758: mollusca, bivalvia) collected in the cost of the state of Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Seo, Daniele; Vasconcellos, Marina B.A.; Saiki, Mitiko; Cathartino, Marilia G.M.; Moreira, Edson G.; Sousa, Eduinetty C.P.M. de

    2011-01-01

    The objective of the present study was to evaluate magnesium and manganese concentrations in Perna perna mussels by applying instrumental neutron activation analysis (INAA). The mussels were collected seasonally from September 2008 to July 2009 at Cocanha Beach in the city of Caraguatatuba (clean region), and at two sites in Santos Bay (Ponta de Itaipu and Palmas Island). The mussel samples were cleaned, grinded, homogenized, lyophilized and then analyzed by INAA. The INAA procedure consisted in the irradiation of the samples and synthetic elemental standards for 10 s, under a thermal neutron flux of 6.6 x 10 12 n cm -2 s -1 in the nuclear research reactor of IPEN-CNEN/SP. The measurements of the gamma radioactivity of the samples and standards were carried out using a hyperpure semiconductor Ge detector, coupled to Digital Spectral Analyzer. The elemental concentrations were calculated by the comparative method. For quality control of analytical results, certified reference materials NIST SRM 1566b oyster tissue and NRC DORM-2 Dogfish Muscle were analyzed and their results indicated good accuracy. The element concentrations in mussels on dry mass basis varied from 2734 ± 205 to 5138 ± 507 mg kg -1 for Mg and from 7.35±0.57 to 29.06±3.35 mg kg -1 for Mn. The results obtained in mussel analysis indicated that the samples collected in Itaipu in the winter season presented higher accumulation of Mg than the other sites. For Mn, the highest concentrations were obtained for the mussels collected in Palmas in summer time. (author)

  11. Threatened freshwater and terrestrial molluscs (Mollusca, Gastropoda et Bivalvia of Santa Catarina State, Southern Brazil: check list and evaluation of regional threats

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available A total of nineteen continental native mollusc species are confirmed for the Santa Catarina State (SC(organized in ten Genera and seven Families, one aquatic Prosobranchia/Caenogastropoda (Ampullariidae,six Pulmonata terrestrial gastropods (one Ellobiidae, three Megalobulimidae and two micro-snails –Charopidae and Streptaxidae and twelve freshwater mussels (eight Mycetopodidae and four Hyriidae. Thesespecies are designated by the International Union for Conservation of the Nature – IUCN as follows: seven as"Vulnerable", six "In Danger" and six “Without Category Established”. The general regional threats that thesespecies are subjected to are briefly analyzed.

  12. Description of two new species of Rissoella Gray, 1847 (Mollusca, Gastropoda, Heterobranchia from Venezuela, with a key to the Caribbean species known for the genus

    Directory of Open Access Journals (Sweden)

    Manuel Caballer Gutierrez

    2011-07-01

    Full Text Available Two new species of the genus Rissoella Gray, 1847 are described from Venezuela, one from the National Park Morrocoy, Rissoella morrocoyensis sp. n. and the other from the Wildlife Refuge Isla de Aves, Rissoella venezolanicola sp. n. R. morrocoyensis sp. n. has a deep umbilicus (partly closed, preumbilical cord, black head, hypobranchial gland marked by a pale yellow boomerang-shaped ribbon and it lives on the leaves of the seagrass Thalassia testudinum Banks & König, 1805. R. venezolanicola sp. n. has an angled preumbilical cord which extends to the columella delimiting a trapezoid, a hypobranchial gland marked by a yellow quaver-shaped ribbon and protoconch with fuchsia highlights. It lives on the brown alga Dictyota spp. The records of Rissoella in the Caribbean are revised and illustrations, a comparative table and a key to the Caribbean species known for the genus are provided.

  13. Biodiversidad de gasterópodos terrestres (Mollusca en el Parque Biológico Sierra de San Javier, Tucumán, Argentina

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    María José Miranda

    2010-09-01

    Full Text Available Se realizó un inventario y se analizaron parámetros de diversidad de la malacofauna terrestre del Parque Biológico Sierra de San Javier. Se llevaron a cabo muestreos cualitativos y cuantitativos en parcelas de 10x10m tomadas en transectas altitudinales, para un total de 22 169 especímenes recolectados. Las identificaciones taxonómicas se llevaron a cabo a nivel de especie. Se construyó una matriz de especies por parcela para analizar patrones de diversidad y se utilizaron estimadores no paramétricos (ICE, ACE, Chao 1 y Chao 2 para calcular la diversidad del Parque, el grado de completitud del muestreo y la agregación espacial de los datos. Se calcularon los índices de Shannon, Simpson, Whittaker y Jaccard. La riqueza del Parque fue estimada en 32 especies distribuidas en 21 géneros y 13 familias. Solo una especie pertenece a Caenogastropoda, el resto son Pulmonados Stylommatophora y Systellommatophora. La familia más representada fue Charopidae mientras que la especie con mayor abundancia relativa fue Adelopoma tucma. La riqueza y diversidad fue levemente mayor en chaco seco que en bosque húmedo de Yungas. Los valores de diversidad obtenidos fueron elevados en comparación con estudios previos realizados en el noroeste Argentino.

  14. The Neotropical land snails (Mollusca, Gastropoda collected by the ‘Comisión Científica del Pacífico’

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    Abraham S.H. Breure

    2017-03-01

    Full Text Available The land snails collected by the ‘Comisión Científica del Pacifíco’ (CCP, a Spanish expedition to South and Central America from 1862–1866, are restudied and revised. The historical context of the expedition and the study of its collected material are described. Biographical data is given for the main persons involved. The land snails were previously studied by Joaquin Hidalgo between 1867 and 1893. A total of 3,470 specimens belonging to 211 species are treated in this paper. Of 34 species mentioned by Hidalgo is his catalogue, the corresponding material could not be located. Bulimus visendus Hidalgo, 1869 is now placed in the genus Synapterpes Pilsbry, 1896, a new combination.

  15. Single cell gel electrophoresis as a tool to assess genetic damage in Heleobia cf. australis (Mollusca: Gastropoda as sentinel for industrial and domestic pollution in Montevideo bay (Uruguay

    Directory of Open Access Journals (Sweden)

    Silvia Villar

    2015-09-01

    Full Text Available AbstractThe knowledge of the extent of DNA damage in aquatic organisms in polluted areas is an important issue because contamination may alter their health at sublethal levels. Although molluscs have been widely used to monitor water pollution, there are no records of in vivo genotoxicity studies. Heleobia cf. australis, is distributed in almost all Uruguayan coastal ecosystems, including highly polluted sites. The comet assay is a damage genetic biomarker based on the migration of negatively charged DNA fragments produced by mutagenic agents in individual cells. Live individuals were collected in the Montevideo Bay (impacted area and Laguna Garzón (control to analyze the presence of mutagenic agents in the former site through comet assay. Cells from organisms of the impacted area showed significantly higher levels of genetic damage than those obtained in the control population, measured by percentage of DNA in the tail. Although preliminary, this approach supports the idea that H. cf. australis could be used as a sentinel to evaluate the presence of mutagenic agents in estuarine environments, alerting to the impact of contamination in its early stages.

  16. An annotated catalogue of Recent Pectinoidea (Mollusca, Pectinidae and Propeamussiidae) type material in the Museum of Natural History, Humboldt University, Berlin

    NARCIS (Netherlands)

    Dijkstra, H.H.; Köhler, F.

    2008-01-01

    This paper lists 22 pectinoid types (21 primary and one secondary) and three potential syntypes in the Museum of Natural History (ZMB) in Berlin. Eight lectotypes are designated herein for the stabilization of taxonomic names: Pecten aequatorialis, Pecten australis, Pecten clathratus, Camptonectes

  17. Evaluation of the levels of Br, Cl, K, Mg, Mn and V in Perna perna Mussels (Linnaeus, 1758: Mollusca, Bivalvia) collected in coast of Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Seo, Daniele; Vasconcellos, Marina B.A.; Saiki, Mitiki; Catharino, Marilia G.M.; Moreira, Edson G.; Sousa, Eduinetty C.P.M. de

    2013-01-01

    In this study the content of Br, Cl, K, Mg, Mn and V was evaluated in samples of Perna perna mussels collected in coastal regions of Sao Paulo (Ponta de Itaipu and Palmas Island, in Santos) subjected to anthropogenic contamination, to compare these values with those of mussels from reference site of Cocanha Beach (in Caraguatatuba). The mussels were collected seasonally from September 2008 to July 2009. They were cleaned, ground, homogenized, lyophilized and then analyzed by Instrumental Neutron Activation Analysis (INAA). The INAA procedure consisted in the irradiation of the samples and synthetic elemental standards for 8 and 10 s, under a thermal neutron flux of 6.6 x 10 12 n cm -2 s -1 in the IEA-R1 nuclear research reactor. For quality control of analytical results, certified reference materials NIST 1566b Oyster Tissue and NIST 2876 Mussel Tissue were analyzed and their results indicated good accuracy. The ranges of concentrations (dry basis) of the elements obtained in mussels collected for the four seasons of the year were: 173.80 to 358.99 mg kg -1 for Br; 45658 ± 1811 to 109166 ± 824 mg kg -1 for Cl; 7043 ± 856 to 12506 ± 675 mg kg -1 for K; 2774 ± 211 to 5691 ± 717 mg kg -1 for Mg; 7.01 ± 0.30 to 29.74 ± 3.32 mg kg -1 for Mn and 0.77 ± 0.02 to 3.43 ± 0.28 mg kg -1 for V. The seasonal and spatial variations of these element concentrations were in this study. (author)

  18. Evaluation of magnesium and manganese in Perna perna mussels (Linnaeus, 1758: mollusca, bivalvia) collected in the cost of the state of Sao Paulo, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Daniele; Vasconcellos, Marina B.A.; Saiki, Mitiko; Cathartino, Marilia G.M.; Moreira, Edson G., E-mail: mbvascon@ipen.b, E-mail: mitiko@ipen.b, E-mail: emoreira@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Sousa, Eduinetty C.P.M. de, E-mail: edvinett@usp.b [Universidade de Sao Paulo (IO/USP), SP (Brazil). Inst. Oceanografico. Lab. de Ecotoxicologia Marinha e Microfitobentos

    2011-07-01

    The objective of the present study was to evaluate magnesium and manganese concentrations in Perna perna mussels by applying instrumental neutron activation analysis (INAA). The mussels were collected seasonally from September 2008 to July 2009 at Cocanha Beach in the city of Caraguatatuba (clean region), and at two sites in Santos Bay (Ponta de Itaipu and Palmas Island). The mussel samples were cleaned, grinded, homogenized, lyophilized and then analyzed by INAA. The INAA procedure consisted in the irradiation of the samples and synthetic elemental standards for 10 s, under a thermal neutron flux of 6.6 x 10{sup 12} n cm{sup -2} s{sup -1} in the nuclear research reactor of IPEN-CNEN/SP. The measurements of the gamma radioactivity of the samples and standards were carried out using a hyperpure semiconductor Ge detector, coupled to Digital Spectral Analyzer. The elemental concentrations were calculated by the comparative method. For quality control of analytical results, certified reference materials NIST SRM 1566b oyster tissue and NRC DORM-2 Dogfish Muscle were analyzed and their results indicated good accuracy. The element concentrations in mussels on dry mass basis varied from 2734 {+-} 205 to 5138 {+-} 507 mg kg{sup -1} for Mg and from 7.35{+-}0.57 to 29.06{+-}3.35 mg kg{sup -1} for Mn. The results obtained in mussel analysis indicated that the samples collected in Itaipu in the winter season presented higher accumulation of Mg than the other sites. For Mn, the highest concentrations were obtained for the mussels collected in Palmas in summer time. (author)

  19. Diet and stable isotope analyses reveal the feeding ecology of the orangeback squid Sthenoteuthis pteropus (Steenstrup 1855 (Mollusca, Ommastrephidae in the eastern tropical Atlantic.

    Directory of Open Access Journals (Sweden)

    Véronique Merten

    Full Text Available In the eastern tropical Atlantic, the orangeback flying squid Sthenoteuthis pteropus (Steenstrup 1855 (Cephalopoda, Ommastrephidae is a dominant species of the epipelagic nekton community. This carnivore squid has a short lifespan and is one of the fastest-growing squids. In this study, we characterise the role of S. pteropus in the pelagic food web of the eastern tropical Atlantic by investigating its diet and the dynamics of its feeding habits throughout its ontogeny and migration. During three expeditions in the eastern tropical Atlantic in 2015, 129 specimens were caught by hand jigging. Stomach content analyses (via visual identification and DNA barcoding were combined with stable isotope data (∂15N and ∂13C of muscle tissue to describe diet, feeding habits and trophic ecology of S. pteropus. Additionally, stable isotope analyses of incremental samples along the squid's gladius-the chitinous spiniform structure supporting the muscles and organs-were carried out to explore possible diet shifts through ontogeny and migration. Our results show that S. pteropus preys mainly on myctophid fishes (e.g. Myctophum asperum, Myctophum nitidulum, Vinciguerria spp., but also on other teleost species, cephalopods (e.g. Enoploteuthidae, Bolitinidae, Ommastrephidae, crustaceans and possibly on gelatinous zooplankton as well. The squid shows a highly opportunistic feeding behaviour that includes cannibalism. Our study indicates that the trophic position of S. pteropus may increase by approximately one trophic level from a mantle length of 15 cm to 47 cm. The reconstructed isotope-based feeding chronologies of the gladii revealed high intra- and inter-individual variability in the squid's trophic position and foraging area. These findings are not revealed by diet or muscle tissue stable isotope analysis. This suggests a variable and complex life history involving individual variation and migration. The role of S. pteropus in transferring energy and nutrients from lower to higher trophic levels may be underestimated and important for understanding how a changing ocean impacts food webs in the eastern Atlantic.

  20. The influence of caffeine and thymol on the survival, growth and reproduction of Subulina octona (Brugüière, 1789 (Mollusca, Subulinidae

    Directory of Open Access Journals (Sweden)

    Paula Ferreira

    2009-08-01

    Full Text Available Subulina octona is a terrestrial snail which serves as an intermediate host for the parasites. It is also an agricultural pest. The aim of this work was to assess, during 120 days, the effects of caffeine and thymol at 2.5 g/L and 5 g/L on the hatchability, survival after hatching, growth and reproduction of S. octona under the laboratory conditions. A total of 240 eggs, 240 juveniles aged 10-day-old, and 240 aged 30-day-old were tested. The results showed that thymol (at 2.5 g/L and 5 g/L and caffeine (at 5 g/L acted as ovicides. In the 10-day-old juveniles, caffeine at 5 g/L caused 25% mortality and at 2.5 g/L it caused 30% mortality. Thymol at 2.5 and 5 g/L caused 20 and 22.5% mortality, respectively. In the 30-day-old juveniles, caffeine at 5 g/L caused 47.5% mortality.Subulina octona é um molusco terrestre que atua como hospedeiro intermediário de parasitos. Também atua como praga agrícola. O objetivo deste trabalho foi avaliar, durante 120 dias, o efeito da cafeína e do timol a 2,5g/L e a 5g/L, sobre a eclodibilidade, a sobrevivência após a eclosão, crescimento e a reprodução de S. octona em condições de laboratório. Foram testados 240 ovos, 240 jovens com 10 e 30 dias de vida. Os resultados dos testes mostraram que o timol (5g/L e 2,5g/L e a cafeína a 5g/L atuaram como ovicida. Nos jovens com 10 dias de vida a cafeína à 5g/L provocou uma mortalidade de 25% e a 2,5 g/L 30%. O timol a 2,5g/L e 5g/L provocou 20 e 22,5% de mortalidade, respectivamente. Nos jovens com 30 dias de vida a cafeína a 5g/L causou 47,5% de mortalidade. Esses resultados sugerem novos estudos no campo.

  1. Characterization of nine microsatellite markers and development of multiplex PCRs for the Chinese huge musel Anodonta (Sinanodonta) woodiana Lea, 1834 (Mollusca, Bivalvia)

    Czech Academy of Sciences Publication Activity Database

    Popa, O. P.; Bartáková, Veronika; Bryja, Josef; Reichard, Martin; Popa, L. O.

    2015-01-01

    Roč. 60, June (2015), s. 234-237 ISSN 0305-1978 R&D Projects: GA ČR GA13-05872S Institutional support: RVO:68081766 Keywords : Invasive species * SSRs * Population genetics * Unionidae Subject RIV: EG - Zoology Impact factor: 0.988, year: 2015

  2. New species of Rissoidae (Mollusca, Gastropoda) from the Archipelago of the Azores (northeast Atlantic) with an updated regional checklist for the family

    OpenAIRE

    Cordeiro,Ricardo; Ávila,Sérgio

    2015-01-01

    Abstract Four new species of shallow-water marine gastropods belonging to the family Rissoidae are described from the Archipelago of the Azores: Setia alexandrae sp. n., Setia ermelindoi sp. n., Setia netoae sp. n., and Manzonia martinsi sp. n. These novelties increase the regional rissoid fauna to 39 species, of which 29 live in shallow-water habitats. A list of the species of Rissoidae from the Azores is presented based on data from the literature and new material examined.

  3. On the doubtful records of Alvania platycephala, Alvania pagodula and Alvania didyma, with the description of two new rissoid species (Mollusca; Gastropoda: Rissoidae)

    OpenAIRE

    Faber, M.J.; Moolenbeek, R.G.

    1987-01-01

    Two new species of Alvania are described from Bermuda. Both species have been wrongly identified in the past. The generic classification is discussed but a definitive statement based only on conchological characters seems impossible.

  4. New species of Rissoidae (Mollusca, Gastropoda) from the Archipelago of the Azores (northeast Atlantic) with an updated regional checklist for the family.

    Science.gov (United States)

    Cordeiro, Ricardo; Ávila, Sérgio P

    2015-01-01

    Four new species of shallow-water marine gastropods belonging to the family Rissoidae are described from the Archipelago of the Azores: Setiaalexandrae sp. n., Setiaermelindoi sp. n., Setianetoae sp. n., and Manzoniamartinsi sp. n. These novelties increase the regional rissoid fauna to 39 species, of which 29 live in shallow-water habitats. A list of the species of Rissoidae from the Azores is presented based on data from the literature and new material examined.

  5. Molecular resolution of the family Dreissenidae (Mollusca: Bivalvia) with emphasis on Ponto-Caspian species, including first report of Mytilopsis leucophaeata in the Black Sea basin.

    Science.gov (United States)

    Therriault, Thomas W; Docker, Margaret F; Orlova, Marina I; Heath, Daniel D; MacIsaac, Hugh J

    2004-03-01

    Considerable uncertainty exists in determination of the phylogeny among extant members of the Dreissenidae, especially those inhabiting the Ponto-Caspian basin, as multiple systematic revisions based on morphological characteristics have failed to resolve relationships within this group of bivalves. In this study we use DNA sequence analyses of two mitochondrial gene fragments, 16S rRNA and cytochrome c oxidase subunit I (COI), to determine phylogenetic relationships among Dreissena rostriformis, D. bugensis, D. polymorpha, D. stankovici, Congeria kusceri, and Mytilopsis leucophaeata. Dreissena stankovici was determined to represent a sister taxa to D. polymorpha and both are more closely related to other extant Dreissena species than Congeria or Mytilopsis. Sequence divergence between D. rostriformis and D. bugensis was relatively low (0.3-0.4%), suggesting that these two taxa constitute a single species. However, environmental differences suggest two races of D. rostriformis, a brackish water race (rostriformis) and a freshwater race (bugensis). Spread of bugensis-type individuals into habitats in the Caspian Sea that are occupied by rostriformis-type individuals may create novel hybridization opportunities. Species-specific molecular markers also were developed in this study since significant intraspecific variation in morphological features complicates dreissenid identification. Using two gene fragments (nuclear 28S and 16S), we identified restriction fragment length polymorphisms (RFLPs) that distinguish among D. rostriformis/bugensis, D. polymorpha, and D. stankovici and revealed the presence of a cryptic invader to the Black Sea basin, Mytilopsis leucophaeata. This is the first report of this North American native in southern Europe.

  6. Population structure, biomass and production of the West African lucinid Keletistes rhizoecus (Bivalvia, Mollusca) in Sivibilagbara swamp at Bodo Creek, Niger Delta, Nigeria

    NARCIS (Netherlands)

    Zabbey, N.; Hart, A. I.; Wolff, W. J.

    2010-01-01

    The West African lucinid bivalve Keletistes rhizoecus (Oliver, Basteria 50:47-64, 1986) is only known from the Niger Delta in Nigeria. Due to inaccessibility of its habitat population biology, growth parameters, biomass, and annual secondary production are unknown. The danger of oil pollution

  7. Is the Schwabe Organ a Retained Larval Eye? Anatomical and Behavioural Studies of a Novel Sense Organ in Adult Leptochiton asellus (Mollusca, Polyplacophora Indicate Links to Larval Photoreceptors.

    Directory of Open Access Journals (Sweden)

    Lauren H Sumner-Rooney

    Full Text Available The discovery of a sensory organ, the Schwabe organ, was recently reported as a unifying feature of chitons in the order Lepidopleurida. It is a patch of pigmented tissue located on the roof of the pallial cavity, beneath the velum on either side of the mouth. The epithelium is densely innervated and contains two types of potential sensory cells. As the function of the Schwabe organ remains unknown, we have taken a cross-disciplinary approach, using anatomical, histological and behavioural techniques to understand it. In general, the pigmentation that characterises this sensory structure gradually fades after death; however, one particular concentrated pigment dot persists. This dot is positionally homologous to the larval eye in chiton trochophores, found in the same neuroanatomical location, and furthermore the metamorphic migration of the larval eye is ventral in species known to possess Schwabe organs. Here we report the presence of a discrete subsurface epithelial structure in the region of the Schwabe organ in Leptochiton asellus that histologically resembles the chiton larval eye. Behavioural experiments demonstrate that Leptochiton asellus with intact Schwabe organs actively avoid an upwelling light source, while Leptochiton asellus with surgically ablated Schwabe organs and a control species lacking the organ (members of the other extant order, Chitonida do not (Kruskal-Wallis, H = 24.82, df = 3, p < 0.0001. We propose that the Schwabe organ represents the adult expression of the chiton larval eye, being retained and elaborated in adult lepidopleurans.

  8. Emergence, development, and maturity of the gonad of two species of chitons "sea cockroach" (Mollusca: Polyplacophora through the early life stages.

    Directory of Open Access Journals (Sweden)

    Omar Hernando Avila-Poveda

    Full Text Available This study describes and recognises, using histological and microscopical examinations on a morphometrical basis, several gonad traits through the early life stages of Chiton articulatus and C. albolineatus. Gonadal ontogenesis, gonad development stages, sexual differentiation, onset of the first sexual maturity, and growth sequences or "early life stages" were determined. In addition, allometry between lengths and body weight pooled for both sexes per each chiton were calculated using equation Y = aX(b . A total of 125 chitons (4≤TL≤40 mm, in total length "TL" were used. All allometric relations showed a strong positive correlation (r, close to 1, with b-values above three, indicating an isometric growth. Gonadal ontogenesis and gonad development stages were categorised into three periods ("Pw" without gonad, "Pe" gonad emergence, and "Pf" gonadal sac formed and four stages ("S0" gametocytogenesis, "S1" gametogenesis, "S2" mature, and "S3" spawning, respectively. Compound digital images were attained for each process. Periods and stages are overlapped among them and between species, with the following overall confidence intervals in TL: Pw 6.13-14.32 mm, Pe 10.32-16.93 mm, Pf 12.99-25.01 mm, S0 16.08-24.34 mm (females and 19.51-26.60 mm (males, S1 27.15-35.63 mm (females and 23.45-32.27 mm (males, S2 24.48-40.24 mm (females and 25.45-32.87 mm (males. Sexual differentiation (in S0 of both chitons occurs first as a female then as a male; although, males reach the onset of the first sexual maturity earlier than females, thus for C. articulatus males at 17 mm and females at 32 mm, and for C. albolineatus males at 23.5 mm and females at 28 mm, all in TL. Four early life stages (i.e., subjuvenile, juvenile, subadult, and adult are described and proposed to distinguish growth sequences. Our results may be useful to diverse disciplines, from developmental biology to fisheries management.

  9. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs of Lymnaea stagnalis and Bithynia tentaculata (Mollusca)

    NARCIS (Netherlands)

    D. Zivkovic (Dana); R. Créton (Robbert); G. Zwaan (Gideon); W.C. de Bruijn (Wim); M.R. Dohmen (M.René)

    1990-01-01

    textabstractDuring extrusion of the first polar body in eggs of Lymnaea stagnalis and Bithynia tentaculata a localized Ca2+ /Mg2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity

  10. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs of Lymnaea stagnalis and Bithynia tentaculata (Mollusca)

    OpenAIRE

    Zivkovic, Dana; Créton, Robbert; Zwaan, Gideon; Bruijn, Wim; Dohmen, M.René

    1990-01-01

    textabstractDuring extrusion of the first polar body in eggs of Lymnaea stagnalis and Bithynia tentaculata a localized Ca2+ /Mg2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity was distributed in a polar fashion, along the cytoplasmic face of the plasma membrane. In the eggs of Lymnaea it was found only in the vegetal hemisphere, whereas in Bithynia eggs it was localized...

  11. Ontogenetic changes in feeding and food preferences of the dog conch Laevistrombus canarium Linnaeus 1758 (Mollusca: Gastropoda) from Merambong shoal, Malaysia

    Science.gov (United States)

    Husna, Wan Nurul Wan Hassan; Mazlan, Abd Ghaffar; Cob, Zaidi Che

    2017-09-01

    Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value, particularly in the aquaculture sector in Malaysia. This study was conducted to determine the feeding and food items of L. canarium at different ontogenetic stages (juveniles, sub-adults and adults) from Merambong shoals, Malaysia. Field observations on feeding activity were conducted, followed by detailed laboratory analysis on the stomach content. Five-minutes observations on randomly selected individuals were conducted at the field sampling site and their feeding activities were recorded with reference to age stage. Various shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10% formalin before being transported to the laboratory for stomach content analyses. Field observations showed that L. canarium mainly grazed on epiphytes occurring on seagrass (46.67%), followed by sediment surface (40%) and epiphytes occurring on macroalgae (13.33%). Stomach content analyses showed a significant difference ( P 0.05) was detected between the three main food items (diatoms, sand particles and detritus) among the ontogenetic stages. Therefore, feeding activity revealed the role of the dog conch in the marine food network. While, classification of the types of food consumed by L. canarium through stomach content analysis determines the particular position of the gastropod in the food chain. Further studies are needed to provide a better insight between trophic relationships of L. canarium with marine ecosystem.

  12. Prevalence and distribution of Angiostrongylus cantonensis (Nematoda, Angiostrongylidae in Achatina fulica (Mollusca, Gastropoda in Baixada Santista, São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Laura Rocha Guerino

    Full Text Available ABSTRACT INTRODUCTION Angiostrongylus cantonensis is causes eosinophilic meningoencephalitis in humans. Worldwide expansion of this nematode is linked to the dispersion of their hosts. This study aimed to determine the prevalence of A. cantonensis infection in Achatina fulica in the nine municipalities that make up Baixada Santista, São Paulo, Brazil. METHODS Angiostrongylus cantonensis larvae were analyzed using optical microscopy. We performed polymerase chain reaction and restriction fragment length polymorphism using restriction endonuclease ClaI, directed to the internal transcribed spacer region 2 of A. cantonensis larval DNA. RESULTS Of the 540 snails analyzed, 117 (21.7% were infected by A. cantonensis. For morphological and morphometric analyses, 60 larvae were used. Second-stage larvae were, on average, 358.2µm long and 26.4µm wide, while third-stage larvae were, on average, 450µm long and 21.12µm wide. The tails of the larvae ended in a fine tip. CONCLUSIONS All municipalities comprising Baixada Santista had A. fulica that were naturally infected with A. cantonensis. All of the observed characteristics were typical of the species.

  13. Prevalence and distribution of Angiostrongylus cantonensis (Nematoda, Angiostrongylidae) in Achatina fulica (Mollusca, Gastropoda) in Baixada Santista, São Paulo, Brazil.

    Science.gov (United States)

    Guerino, Laura Rocha; Pecora, Iracy Lea; Miranda, Marcel Sabino; Aguiar-Silva, Cryslaine; Carvalho, Omar Dos Santos; Caldeira, Roberta Lima; Silva, Reinaldo José da

    2017-01-01

    Angiostrongylus cantonensis is causes eosinophilic meningoencephalitis in humans. Worldwide expansion of this nematode is linked to the dispersion of their hosts. This study aimed to determine the prevalence of A. cantonensis infection in Achatina fulica in the nine municipalities that make up Baixada Santista, São Paulo, Brazil. Angiostrongylus cantonensis larvae were analyzed using optical microscopy. We performed polymerase chain reaction and restriction fragment length polymorphism using restriction endonuclease ClaI, directed to the internal transcribed spacer region 2 of A. cantonensis larval DNA. Of the 540 snails analyzed, 117 (21.7%) were infected by A. cantonensis. For morphological and morphometric analyses, 60 larvae were used. Second-stage larvae were, on average, 358.2µm long and 26.4µm wide, while third-stage larvae were, on average, 450µm long and 21.12µm wide. The tails of the larvae ended in a fine tip. All municipalities comprising Baixada Santista had A. fulica that were naturally infected with A. cantonensis. All of the observed characteristics were typical of the species.

  14. Complete mitochondrial genome of the giant African snail, Achatina fulica (Mollusca: Achatinidae): a novel location of putative control regions (CR) in the mitogenome within Pulmonate species.

    Science.gov (United States)

    He, Zhang-Ping; Dai, Xia-Bin; Zhang, Shuai; Zhi, Ting-Ting; Lun, Zhao-Rong; Wu, Zhong-Dao; Yang, Ting-Bao

    2016-01-01

    The whole sequence (15,057 bp) of the mitochondrial DNA (mtDNA) of the terrestrial snail Achatina fulica (order Stylommatophora) was determined. The mitogenome, as the typical metazoan mtDNA, contains 13 protein-coding genes (PCG), 2 ribosomal RNA genes (rRNA) and 22 transfer RNA genes (tRNA). The tRNA genes include two trnS without standard secondary structure. Interestingly, among the known mitogenomes of Pulmonata species, we firstly characterized an unassigned lengthy sequence (551 bp) between the cox1 and the trnV which may be the CR for the sake of its AT bases usage bias (65.70%) and potential hairpin structure.

  15. New records of Omalonyx matheroni (Pontiez & Michaud, 1835 (Mollusca, Gastropoda, Succineidae for the São Paulo and Paraná States.

    Directory of Open Access Journals (Sweden)

    Maria Cristina Dreher Mansur

    2009-06-01

    Full Text Available Omalonyx matheroni is a succineid gastropod that lives on aquatic macrophytes and on emergent vegetation in the wetlands of inner deltas, lakes and dikes. Occurrences of this species were recorded in the municipalities of Ibitinga (SP and Paranaguá (PR, broadening its distribution southwards in South America. Until now this species had been recorded in Demerara (Guiana, Zanderij and Belwaarde (Suriname, Guiana Francesa, Peru, Limoncocha (Equador, Amazonas, Pará, Pernambuco, Rio de Janeiro and Minas Gerais (Brazil, as well as on the islands of Guadalupe and Trinidade.

  16. Megadenus atrae n. sp., an endoparasitic eulimid gastropod (Mollusca) from the black sea cucumber Holothuria atra Jaeger (Aspidochirotida: Holothuriidae) in the Indo-West Pacific.

    Science.gov (United States)

    Takano, Tsuyoshi; Warén, Anders; Kano, Yasunori

    2017-07-01

    An eulimid gastropod, Megadenus atrae n. sp., endoparasitic in the cloacal chamber of the black sea cucumber Holothuria atra Jaeger is described from Okinawa, Japan, as the fifth species of the genus. Conspecific specimens have also been found from southeast India, northeast Australia and New Caledonia. The generic assignment is justified by the presence of (i) a thick, long proboscis that bears a large fold (pseudopallium) near the base and a collar-like structure at the middle, (ii) a thin, globose shell that is covered by the pseudopallium, and (iii) sexual dimorphism with the female generally larger than the male. The new species is distinguishable from the four previously described congeners by its cauldron-shaped pseudopallium, moderately-developed collar of the proboscis and rounded basal lip of the shell. The comparisons of the size and sex of solitary and paired individuals support a previous hypothesis that the species of Megadenus Rosén, 1910 are protandrous with environmental sex determination. The present species occurs mostly as monogamous pairs despite its very low population density, implying that the presence of a conspecific individual acts as a cue for larval settlement. Both mechanisms would increase individual reproductive success in such permanent parasites with low prevalence and abundance as the species of Megadenus.

  17. Cell proliferation and apoptosis in gill filaments of the lucinid Codakia orbiculata (Montagu, 1808) (Mollusca: Bivalvia) during bacterial decolonization and recolonization.

    Science.gov (United States)

    Elisabeth, Nathalie H; Gustave, Sylvie D D; Gros, Olivier

    2012-08-01

    The shallow-water bivalve Codakia orbiculata which harbors gill-endosymbiotic sulfur-oxidizing γ-proteobacteria can lose and acquire its endosymbionts throughout its life. Long-term starvation and recolonization experiments led to changes in the organization of cells in the lateral zone of gill filaments. This plasticity is linked to the presence or absence of gill-endosymbionts. Herein, we propose that this reorganization can be explained by three hypotheses: (a) a variation in the number of bacteriocytes and granule cells due to proliferation or apoptosis processes, (b) a variation of the volume of these two cell types without modification in the number, and (c) a combination of both number and cell volume variation. To test these hypotheses, we analyzed cell reorganization in terms of proliferation and apoptosis in adults submitted to starvation and returned to the field using catalyzed reporter deposition fluorescence in situ hybridization, immunohistochemistry, and structural analyses. We observed that cell and tissue reorganization in gills filaments is due to a variation in cell relative abundance that maybe associated with a variation in cell apparent volume and depends on the environment. In fact, bacteriocytes mostly multiply in freshly collected and newly recolonized individuals, and excess bacteriocytes are eliminated in later recolonization stages. We highlight that host tissue regeneration in gill filaments of this symbiotic bivalve can occur by both replication of existing cells and division of undifferentiated cells localized in tissular bridges, which might be a tissue-specific multipotent stem cell zone. Copyright © 2012 Wiley Periodicals, Inc.

  18. Chaetogaster limnaei (annelida: oligochaeta) as a parasite of the zebra mussel Dreissena polymorpha, and the quagga mussel Dreissena bugensis (mollusca: bivalvia).

    Science.gov (United States)

    Conn, D B; Ricciardi, A; Babapulle, M N; Klein, K A; Rosen, D A

    1996-01-01

    Dreissenid mussels, Dreissena polymorpha and D. bugensis, were found to be infected by the naidid oligochaete Chaetogaster limnaei at four sites in the St. Lawrence River. This is the first report of this species infecting dreissenids anywhere in the world. Most worms inhabited the mantle cavity, where they caused erosion of the mantle and gill epithelia as determined by histopathological examination. Others penetrated various tissues; one had invaded the ovary and was feeding on oocytes and ovarian tissues. Of 606 mussels examined, 166 (27.4%) harbored at least 1 C. limnaei. The prevalence varied between 1% and 80%, depending on the collection site and date. The worms were slightly but significantly more prevalent in D. bugensis than in D. polymorpha. The intensity ranged from 1 to 18 worms per infected host. Variations in prevalence and intensity were not related to the size or sex of the host, but the data did suggest some seasonality.

  19. Novos registros de Omalonyx matheroni (Pontiez & Michaud, 1835 (Mollusca, Gastropoda, Succineidae para os Estados de São Paulo e Paraná, Brasil

    Directory of Open Access Journals (Sweden)

    Janine Oliveira Arruda

    2009-08-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2009v22n2p187 Omalonyx matheroni é um gastrópode sucineídeo que ocorre nas macrófitas aquáticas e vegetações adjacentes de planície de inundação de rios, em lagos e açudes. Registra-se a ocorrência dessa espécie para os municípios de Ibitinga (SP e Paranaguá (PR, estendendo sua distribuição mais ao sul da América do Sul. Até o presente momento, a espécie tinha sido registrada para Demerara (Guiana, Zanderij e Belwaarde (Suriname, Guiana Francesa, Peru, Limoncocha (Equador, Amazonas, Pará, Pernambuco, Rio de Janeiro e Minas Gerais (Brasil, além das ilhas de Guadalupe e Trinidade.

  20. [Lipid and fatty acid profile of Perna viridis, green mussel (Mollusca: Bivalvia) in different areas of the Eastern Venezuela and the West Coast of Trinidad].

    Science.gov (United States)

    Koftayan, Tamar; Milano, Jahiro; D'Armas, Haydelba; Salazar, Gabriel

    2011-03-01

    The species Perna viridis is a highly consumed species, which fast growth makes it an interesting aquaculture alternative for Venezuelan and Trinidad coasts. With the aim to contribute with its nutritional value information, this study analyzed lipid and fatty acid contents from samples taken in five locations from Eastern Venezuela and three from Trinidad West Coast. Total lipids were extracted and quantified, from a pooled sample of 100 organisms per location, by standard gravimetric methods, and their identification and quantification was done by TLC/FID (Iatroscan system). Furthermore, the esterified fatty acids of total lipid, phospholipids and triacylglycerols were identified and quantified by gas chromatography. Eastern Venezuela samples from Los Cedros, La Brea and Chaguaramas showed the highest total lipid values of 7.92, 7.74 and 7.53, respectively, and the minimum values were obtained for La Restinga (6.08%). Among lipid composition, Chacopata samples showed the lowest phospholipid concentration (48.86%) and the maximum values for cholesterol (38.87%) and triacylglycerols (12.26%); besides, La Esmeralda and Rio Caribe samples exhibited maximum phospholipids (88.71 and 84.93 respectively) and minimum cholesterol (6.50 and 4.42%) concentrations. Saturated fatty acids represented between 15.04% and 65.55% within total lipid extracts, with maximum and minimum values for La Esmeralda and Chacopata, respectively. Polyunsaturated results resulted between 7.80 and 37.18%, with higher values in La Brea and lower values in La Esmeralda. For phospholipids, saturated fatty acids concentrations varied between 38.81 and 48.68% for Chaguaramas and Chacopata samples, respectively. In the case of polyunsaturated fatty acids, these varied between non detected and 34.51%, with high concentrations in Los Cedros (27.97%) and Chaguaramas (34.51%) samples. For the triacylglycerols, the saturated fatty acids composition oscillated between 14.27 and 53.80% with low concentrations for Chacopata and high concentration for La Restinga; the polyunsaturated fatty acids were between 4.66 and 35.55% with lower values for Chacopata and higher values for Chaguaramas samples. P. viridis is recommended for human being consumption, according to the high content of unsaturated fatty acids found for this species.

  1. Crecimiento del pulpo Octopus maya (Mollusca: Cephalopoda de la costa de Yucatán, México: un análisis de largo plazo

    Directory of Open Access Journals (Sweden)

    Marta Rocío Nepita Villanueva

    2001-03-01

    Full Text Available Los parámetros de crecimiento del pulpo (Octopus maya de las costas de Yucatán (México fueron estimados en siete años comprendidos entre 1983-1987, 1989 y 1992. A tales efectos se realizó un análisis de frecuencia de tallas de 19 251 pulpos muestreados de la captura comercial, con un intervalo de longitud de manto comprendido entre 50 y 240 mm. Se usaron los métodos indirectos ELEFAN, PROJMAT y SLCA. La incertidumbre de las estimaciones inherente a cada método y derivada del diseño de muestreo fue analizada con la técnica jackknife. Los parámetros de crecimiento L y K se unificaron a efectos comparativos mediante el índice phi prima (. El método ELEFAN resultó ser el más adecuado para estimar los parámetros de crecimiento de O. maya, brindando valores en el rango de aquellos previamente reportados en la literatura, mientras que PROJMAT y SLCA mostraron problemas en la convergencia de los parámetros, y tendieron a subestimarlos. Las estimaciones mediante jackknife detectaron poca variabilidad intermensual en pero gran variabilidad interanual. Los estimadores de precisión de la técnica jackknife, error porcentual y coeficiente de variación porcentual, no difirieron significativamente entre métodos. Las estimaciones de derivadas del ELEFAN variaron entre 4.19 y 5.23, coincidiendo con aquellas reportadas en la literatura (entre 4.25 y 4.91, mientras que PROJMAT y SLCA aportaron valores significativamente menores. Los resultados de dicho métodos condicen además con aspectos de la biología de la especie (e.g., corta longevidad. Sugerimos utilizar el ELEFAN conjuntamente con jackknife para estimar los parámetros de crecimiento de Octopus maya.Growth of the octopus (Octopus maya off Yucatan (Mexico was estimated from a long-term study (seven years by the length-based methods ELEFAN, PROJMAT and SLCA. Some 19 251 octopuses with a range of mantle length between 50 and 240 mm were sampled from commercial landings in 1983 - 1987, 1989 and 1992. The jackknife technique was applied to deal with uncertainty in growth estimates resulting from chance variations in sampling design. The growth index was used for comparative purposes. Results differed markedly among methods: ELEFAN produced parameter estimates within the range reported in the literature, whereas PROJMAT and SLCA showed problems to converge in an optimum combination of parameters, and tended to underestimate them. Jackknife analysis revealed very low intraannual variability in but high variability among years, especially when applying PROJMAT. No significant differences were found in precision parameters -percent error and coefficient of variation- among methods. Estimates of derived by ELEFAN varied between 4.19 and 5.23 and agreed with those reported in the literature (between 4.25 and 4.91, whereas PROJMAT and SLCA estimates were significantly lower. We suggest the use of ELEFAN, together with jackknife to estimate growth parameters of Octopus maya.

  2. Biología reproductiva del pulpo Octupus mimus (Mollusca: Cephalopoda de la región de Matarani, Arequipa, Perú

    Directory of Open Access Journals (Sweden)

    Victor Ishiyama

    2014-06-01

    Full Text Available De mayo de 1995 a abril de 1996, se realizaron al azar muestreos mensuales de 25 ejemplares de Octopus mimus de los desembarques del puerto de Matarani, Arequipa (16° 59'40"S y 72° 06'13"W. Son animales gonocóricos, presentan dimorfismo sexual, y los machos tienen el brazo ectocotilizado o copulador. La proporción de sexos fue de 2,1:1,0 a favor de los machos; se determinaron ocho estadios de desarrollo de los ovocitos, durante la ovogénesis. De acuerdo a su comportamiento reproductivo, se estableció la siguiente escala de madurez gonadal: a indiferenciado, b inmaduro, c inicio de maduración, d en desarrollo, e maduros, fl cópula, g postcópula, autofecundación y evacuación, h postevacuación. Las hembras maduras se encontraron preferentemente, en la primavera y verano; los machos maduros a fines de la primavera y en el verano; la cópula se realizó preferentemente durante el verano; la autofecundación y evacuación de los huevos, se evidenciaron en agosto (50%, octubre 50%, noviembre (71,4%, diciembre (33% y enero (33%. La primera madurez en los machos se encontró a los 9,5 cm y en las hembras a los 12,5 cm de la longitud dorsal del cuerpo. Se observó algunas hembras con ovocitos maduros en lisis y con inicio de ovogénesis avanzada de un nuevo ciclo, que evidencia que no todas las hembras mueren después de cuidar los huevos hasta el final de la eclosión.

  3. Analysis of trace elements in the shells of short-necked clam Ruditapes philippinarum (Mollusca: Bivalvia) with respect to reconstruction of individual life history

    International Nuclear Information System (INIS)

    Arakawa, Jumpei; Sakamoto, Wataru

    1998-01-01

    Strontium (Sr) concentration in the shells of short-necked clams collected at different locations (Shirahama, warm area and Maizuru, cold area, Japan) was analyzed by two methods, PIXE and EPMA. The Sr concentration of external surface of shell umbo, which was made during short term at early benthic phase, was analyzed by PIXE, and was ranged from 1000 to 3500 ppm for individuals. The Sr concentration of clams collected at Shirahama showed positive correlation with shell length (SL) in individuals with SL < 31 mm, whereas clams collected at Maizuru did not show significant correlation. This result may be caused from the difference of the spawning seasons between two areas. The Sr concentration of cross section of shell umbo, which develops thicker continuously during their life to form faint stratum structure, was analyzed by EPMA along the line across the stratum structure. Some surges and long term waving patterns of the Sr concentration were observed. These results suggest that the life histories of individual clams could be recorded in the shell umbo cross sections as variations of trace elements and analyses of trace elements could clarify the histories of individual clams. (author)

  4. Occurrence, population dynamics and habitat characterization of Mytella guyanensis (Lamarck, 1819 (Mollusca, Bivalvia in the Paraíba do Norte river estuary

    Directory of Open Access Journals (Sweden)

    Alberto Kioharu Nishida

    1995-01-01

    Full Text Available A survey of Mytellaguyanensis occurrence and population dynamics were performed in the Paraíba do Norte river estuary. The characterization and the influence of temperature, salinity and substrate, as well as the associated fauna and flora on the population were also examined. Mytella guyanensis lives buried in the substrate of the mangrove intertidal zone of the Paraíba do Norte river estuary, from the mouth to 24 km upriver. Average annual density of this bivalve species was 5.2 individuals per m², with a predominantly aggregated distribution. The most frequent size was between 4.5 and 5.5 cm in length. Analysis of the substrate demonstrated the presence of two types of substrates in relation to the percentage of silt and clay and the water content. Besides interfering in the population density, the substrate heterogeneity may be a decisive factor in aggregation. Eight species of crustacean decapods and one bivalve species were identified as associated fauna.A ocorrência de M, guyanensis no estuário do Rio Paraíba do Norte foi mapeada, determinando-se sua presença ao longo dos afluentes e ilhas aí existentes. O estudo da dinâmica da população foi realizado em área protegida da Ilha da Restinga, coletando-se os animais ao longo de 37 transecções. A cada mês foram feitos 60 lançamentos com um delimitador de 0,1 m², sobre uma ou mais transecções. Todo o substrato foi retirado juntamente com os exemplares de M. guyanensis e a fauna associada, até a profundidade de 10 cm. A triagem dos exemplares menores foi feita por peneiramento do substrato. O tipo de substrato foi anotado a cada lançamento. Dois tipos de substrato estão presentes na área: um substrato de tipo consistente, constituido por 89.7% de silte e argila e 10.3% de areia fina e outro de tipo não consistente contendo 74.5% de silte e argila e 25.5% de areia fina. O substrato de tipo não consistente apresenta quantidade de água significativamente maior que o de tipo consistente. Mytella guyanensis vive enterrada no solo numa profundidade máxima de 1,0 cm, sempre envolvida pelos filamentos do bisso. A densidade média anual observada para a espécie foi de 5,2 indivíduos por m²; a distribuição espacial predominante foi do tipo agregado, sofrendo interferência do tipo de substrato presente. Houve preferência de fixação da espécie pelo substrato do tipo consistente. Animais entre 4,5 e 5,5 cm de comprimento ocorrem o ano todo, sendo mais numerosos aqueles com comprimento entre 4,5 e 5,0 cm. A presença de formas jovens foi assinalada em baixa frequência em alguns meses do ano. A salinidade da água estuarina variou de acordo com o regime pluviométrico da região, permanecendo dentro dos níveis de tolerância da espécie. A fauna associada está representada por oito espécies de crustáceos e por uma de molusco bivalve.

  5. Diet and stable isotope analyses reveal the feeding ecology of the orangeback squid Sthenoteuthis pteropus (Steenstrup 1855) (Mollusca, Ommastrephidae) in the eastern tropical Atlantic.

    Science.gov (United States)

    Merten, Véronique; Christiansen, Bernd; Javidpour, Jamileh; Piatkowski, Uwe; Puebla, Oscar; Gasca, Rebeca; Hoving, Henk-Jan T

    2017-01-01

    In the eastern tropical Atlantic, the orangeback flying squid Sthenoteuthis pteropus (Steenstrup 1855) (Cephalopoda, Ommastrephidae) is a dominant species of the epipelagic nekton community. This carnivore squid has a short lifespan and is one of the fastest-growing squids. In this study, we characterise the role of S. pteropus in the pelagic food web of the eastern tropical Atlantic by investigating its diet and the dynamics of its feeding habits throughout its ontogeny and migration. During three expeditions in the eastern tropical Atlantic in 2015, 129 specimens were caught by hand jigging. Stomach content analyses (via visual identification and DNA barcoding) were combined with stable isotope data (∂15N and ∂13C) of muscle tissue to describe diet, feeding habits and trophic ecology of S. pteropus. Additionally, stable isotope analyses of incremental samples along the squid's gladius-the chitinous spiniform structure supporting the muscles and organs-were carried out to explore possible diet shifts through ontogeny and migration. Our results show that S. pteropus preys mainly on myctophid fishes (e.g. Myctophum asperum, Myctophum nitidulum, Vinciguerria spp.), but also on other teleost species, cephalopods (e.g. Enoploteuthidae, Bolitinidae, Ommastrephidae), crustaceans and possibly on gelatinous zooplankton as well. The squid shows a highly opportunistic feeding behaviour that includes cannibalism. Our study indicates that the trophic position of S. pteropus may increase by approximately one trophic level from a mantle length of 15 cm to 47 cm. The reconstructed isotope-based feeding chronologies of the gladii revealed high intra- and inter-individual variability in the squid's trophic position and foraging area. These findings are not revealed by diet or muscle tissue stable isotope analysis. This suggests a variable and complex life history involving individual variation and migration. The role of S. pteropus in transferring energy and nutrients from lower to higher trophic levels may be underestimated and important for understanding how a changing ocean impacts food webs in the eastern Atlantic.

  6. Molecular identification of similar species of the genus Biomphalaria (Mollusca: Planorbidae determined by a polymerase chain reaction-restriction fragment length polymorphism

    Directory of Open Access Journals (Sweden)

    Caldeira Roberta Lima

    1998-01-01

    Full Text Available The freshwater snails Biomphalaria straminea, B. intermedia, B. kuhniana and B. peregrina, are morphologically similar; based on this similarity the first three species were therefore grouped in the complex B. straminea. The morphological identification of these species is based on characters such as vaginal wrinkling, relation between prepuce: penial sheath:deferens vas and number of muscle layers in the penis wall. In this study the polymerase chain reaction restriction fragment length polymorphism technique was used for molecular identification of these molluscs. This technique is based on the amplification of the internal transcribed spacer regions ITS1 e ITS2 of the ribosomal RNA gene and subsequent digestion of these fragments by restriction enzymes. Six enzymes were tested: Dde I, Mnl I, Hae III, Rsa I, Hpa II e Alu I. The restriction patterns obtained with DdeI presented the best profile for separation of the four species of Biomphalaria. The profiles obtained with all the enzymes were used to estimate the genetic distances among the species through analysis of common banding patterns.

  7. The complete mitochondrial genome of the land snail Cornu aspersum (Helicidae: Mollusca: intra-specific divergence of protein-coding genes and phylogenetic considerations within Euthyneura.

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    Juan Diego Gaitán-Espitia

    Full Text Available The complete sequences of three mitochondrial genomes from the land snail Cornu aspersum were determined. The mitogenome has a length of 14050 bp, and it encodes 13 protein-coding genes, 22 transfer RNA genes and two ribosomal RNA genes. It also includes nine small intergene spacers, and a large AT-rich intergenic spacer. The intra-specific divergence analysis revealed that COX1 has the lower genetic differentiation, while the most divergent genes were NADH1, NADH3 and NADH4. With the exception of Euhadra herklotsi, the structural comparisons showed the same gene order within the family Helicidae, and nearly identical gene organization to that found in order Pulmonata. Phylogenetic reconstruction recovered Basommatophora as polyphyletic group, whereas Eupulmonata and Pulmonata as paraphyletic groups. Bayesian and Maximum Likelihood analyses showed that C. aspersum is a close relative of Cepaea nemoralis, and with the other Helicidae species form a sister group of Albinaria caerulea, supporting the monophyly of the Stylommatophora clade.

  8. Effects of endocrine disruptors on prosobranch snails (Mollusca: Gastropoda) in the laboratory. Part I: Bisphenol A and octylphenol as xeno-estrogens.

    Science.gov (United States)

    Oehlmann, J; Schulte-Oehlmann, U; Tillmann, M; Markert, B

    2000-12-01

    The effects of suspected endocrine disrupting chemicals on freshwater and marine prosobranch species were analysed in laboratory experiments. In this first publication, the responses of the freshwater snail Marisa cornuarietis and of the marine prosobranch Nucella lapillus to the xeno-estrogenic model compounds bisphenol A (BPA) and octylphenol (OP) are presented at nominal concentration ranges between 1 and 100 micrograms/L. Marisa was exposed during 5 months using adult specimens and in a complete life-cycle test for 12 months. In both experiments, the xeno-estrogens induced a complex syndrome of alterations in female Marisa referred to as "superfemales" at the lowest concentrations. Affected specimens were characterised by the formation of additional female organs, an enlargement of the accessory pallial sex glands, gross malformations of the pallial oviduct section resulting in an increased female mortality, and a massive stimulation of oocyte and spawning mass production. The effects of BPA and OP were comparable at the same nominal concentrations. An exposure to OP resulted in inverted U-type concentration response relationships for egg and spawning mass production. Adult Nucella from the field were tested for three months in the laboratory. As in Marisa, superfemales with enlarged accessory pallial sex glands and an enhancement of oocyte production were observed. No oviduct malformations were found probably due to species differences in the gross anatomical structure of the pallial oviduct. A lower percentage of exposed specimens had ripe sperm stored in their vesicula seminalis and additionally male Nucella exhibited a reduced length of penis and prostate gland when compared to the control. Because statistically significant effects were observed at the lowest nominal test concentrations (1 microgram BPA or OP/L), it can be assumed that even lower concentrations may have a negative impact on the snails. The results show that prosobranchs are sensitive to endocrine disruption at environmentally relevant concentrations and that especially M. cornuarietis is a promising candidate for a future organismic invertebrate model to identify endocrine-mimetic test compounds.

  9. Insights into the relationships of Palearctic and Nearctic lymnaeids (Mollusca : Gastropoda by rDNA ITS-2 sequencing and phylogeny of stagnicoline intermediate host species of Fasciola hepatica

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    Bargues M.D.

    2003-09-01

    Full Text Available Fascioliasis by Fasciola hepatica is the vector-borne disease presenting the widest latitudinal, longitudinal and altitudinal distribution known. F. hepatica shows a great adaptation power to new environmental conditions which is the consequence of its own capacities together with the adaptation and colonization abilities of its specific vector hosts, freshwater snails of the family Lymnaeidae. Several lymnaeid species only considered as secondary contributors to the liver fluke transmission have, however, played a very important role in the geographic expansion of this disease. Many of them belong to the so-called "stagnicoline" type group. Stagnicolines have, therefore, a very important applied interest in the Holarctic region, to which they are geographically restricted. The present knowledge on the genetics of stagnicolines and on their parasite-host interrelationships is, however, far from being sufficient. The present paper analyses the relationships between Palaearctic and Nearctic stagnicoline species on the base of the new light furnished by the results obtained in nuclear rDNA ITS-2 sequencing and corresponding phylogenetic studies of the lymnaeid taxa Lymnaea (Stagnicola occulta, L. (S. palustris palustris (topotype specimens and L.(S. p. turricula from Europe. Natural infections with F. hepatica have been reported in all of them. Surprisingly, ITS-2 length and G C content of L. occulta were similar and perfectly fitted within the respective ranges known in North American stagnicolines. Nucleotide differences and genetic distances were higher between L. occulta and the other European stagnicolines than between L. occulta and the North American ones. The ITS-2 sequence of L. p. turricula from Poland differed from the other genotypes known from turricula in Europe. The phylogenetic trees using the maximum-parsimony, distance and maximum-likelihood methods confirmed (i the inclusion of L. occulta in the branch of North American stagnicolines, (iii the link between the North American stagnicolines-L. occulta group with Galba truncatula, and (iii the location of the L. p. turricula genotype from Poland closer to L. p. palustris than to other European L. p. turricula genotypes. The Palaearctic species occulta is included in the genus Catascopia, together with the Nearctic species catascopium, emarginata and elodes. The results suggest a potential of transmission capacity for C. occulta higher than that of other European stagnicolines or Omphiscola glabra. The relatively low genetic distances between C. occulta and G. truncatula and the clustering of both species in the same clade suggest that C.occulta may be potentially considered as the second lymnaeid intermediate host species of F. hepatica in importance in eastern and northern Europe, and probably also western and central Asia, after G. truncatula. L. p. turricula may be considered as a potential secondary vector of F. hepatica, at a level similar tot that of L.p. palustris.

  10. Bait formulations of molluscicides and their effects on biochemical changes in the ovotestis of snail Lymnaea acuminata (Mollusca; Gastropoda:Lymnaeidae

    Directory of Open Access Journals (Sweden)

    Pradeep Kumar

    2011-10-01

    Full Text Available The effect of sub-lethal feeding of bait formulations containing molluscicidal component of Ferula asafoetida (ferulic acid, umbelliferone, Syzygium aromaticum (eugenol and Carum carvi (limonene on biochemical changes in the ovotestis of snail Lymnaea acuminata were studied. Bait formulations feeding to L. acuminata were studied in clear glass aquaria having diameter of 30 cm. Baits were prepared from different binary combinations of attractant amino acid (valine, aspartic acid, lysine and alanine 10 mM in 100 mL of 2% agar solution + sub-lethal (20% and 60% of 24h LC50 doses of different molluscicides (ferulic acid, umbelliferone, eugenol and limonene. These baits caused maximum significant reduction in free amino acid, protein, DNA, RNA levels i.e. 41.37, 23.56, 48.36 and 14.29% of control in the ovotestis of the snail, respectively. Discontinuation of feeding after treatment of 60% of 96h LC50 of molluscicide containing bait for next 72h caused a significant recovery in free amino acid, protein, DNA and RNA levels in the ovotestis of L. acuminata.

  11. Bioaccumulation and elimination of 60 Co and 137 Cs by Anomalocardia brasiliana (Gmelin, 1791) (Mollusca bivalvia). Remobilization of 60 Co, retained in marine sediment by microbial activity

    International Nuclear Information System (INIS)

    Mayr, L.M.

    1984-05-01

    It was studied the capacity of a bi valve mollusc Anomalocardia brasiliana, which lives in the local bottom sediment, to remobilize 60 Co previously sorbed in the sediment. Laboratory experiments demonstrated that the transference of 60 Co from the sediment to the animal was insignificant (bioaccumulation factor (BF) of the order of 10 -3 ). At the same time, the capacity of microorganisms, present in the bottom sediment, to remobilize 60 Co was studied. The results showed that this via of transference was important, considering the much greater microorganism biomass in relation to the biomass of bentonic organisms, as a whole. For 137 Cs the determined BF from water to the animal was 2.2. and, as in the case of 60 Co, the soft tissues concentrated more 137 Cs than shell. Remaining viscera showed the highest BFs. In another series of experiments, the loss of 60 Co or 137 Cs, previously accumulated by A. brasiliana, was followed in aquaria with or without sediment and the respective biological half-lives were calculated. Soft tissues retained 60 Co longer (biological half-life = 117 days) than shells, whereas for 137 Cs the opposite was observed and shells showed a biological half life of 38.5 days. The low values of 60 Co and 137 Cs BF S do not allow to classify A. brasiliana as good biological indicator for pollution by there radionuclides. However since A brasiliana is consumed by the local population and is commercialized to other areas, it was recommended that its contamination by 60 Co or 137 Cs should be monitored. (author)

  12. El loco Concholepas concholepas (Bruguière, 1789) (Mollusca: Gastropoda: Muricidae) como recurso durante el Holoceno Temprano-Medio en Los Vilos, Chile central

    OpenAIRE

    Báez, Pedro; Arata, Javier; Jackson, Donald

    2004-01-01

    Se estudió la abundancia relativa del loco, Concholepas concholepas, y las causas posibles de su variabilidad en los conchales culturales más antiguos del Holoceno Temprano-Medio del litoral de Los Vilos (31º55'S, 71º32'W). Las muestras se obtuvieron en excavaciones arqueológicas de cinco sitios y se dataron con C14: Punta Purgatorio (LV079: 10.040 ± 70 años antes del presente, a.a.p.), Caleta Ñagué (LV098: 10.120 ± 80 a.a.p.), Dunas de Agua Amarilla (LV166: 6.700 ± 60 a.a.p.), Borde Norte de...

  13. Preliminary report on the geographical distribution of the species of Carinariidae and Pterotracheidae (Heteropoda, Mollusca) from the International Indian Ocean Expedition

    Digital Repository Service at National Institute of Oceanography (India)

    Aravindakshan, P.N.

    This is a description of the distribution in the Indian Ocean of species belonging to two families of the Heteropoda, the Carinariidae and Pterotracheidae The observations are based on plankton collected by Anton Brunn, Argo, Pionner and Vityaz...

  14. New species of Rissoidae (Mollusca, Gastropoda from the Archipelago of the Azores (northeast Atlantic with an updated regional checklist for the family

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    Ricardo Cordeiro

    2015-02-01

    Full Text Available Four new species of shallow-water marine gastropods belonging to the family Rissoidae are described from the Archipelago of the Azores: Setia alexandrae sp. n., S. ermelindoi sp. n., S. netoae sp. n., and Manzonia martinsi sp. n. These novelties increase the regional rissoid fauna to 39 species, of which 29 live in shallow-water habitats. A list of the species of Rissoidae from the Azores is presented based on data from the literature and new material examined.

  15. New species of Rissoidae (Mollusca, Gastropoda) from the Archipelago of the Azores (northeast Atlantic) with an updated regional checklist for the family

    Science.gov (United States)

    Cordeiro, Ricardo; Ávila, Sérgio P.

    2015-01-01

    Abstract Four new species of shallow-water marine gastropods belonging to the family Rissoidae are described from the Archipelago of the Azores: Setia alexandrae sp. n., Setia ermelindoi sp. n., Setia netoae sp. n., and Manzonia martinsi sp. n. These novelties increase the regional rissoid fauna to 39 species, of which 29 live in shallow-water habitats. A list of the species of Rissoidae from the Azores is presented based on data from the literature and new material examined. PMID:25685020

  16. Genetic Population Structure and Demographic History of the Widespread Common Shipworm Teredo navalis Linnaeus 1758 (Mollusca: Bivalvia: Teredinidae in European Waters Inferred from Mitochondrial COI Sequence Data

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    Ronny Weigelt

    2017-06-01

    Full Text Available The first documented scientific reports of the common marine shipworm Teredo navalis (Bivalvia for Central European waters date back to the time between 1700 and 1730 in the Netherlands. During the following centuries there were several irregular mass occurrences reported for both the North Sea and the Baltic Sea. These events were accompanied by massive destruction of wooden ships and coastal protection structures. In this study, the first population analysis of T. navalis is presented with the aim to detect the genetic population structure in the waters of Central Europe. The mtDNA COI (cytochrome c oxidase subunit I locus was found as suitable molecular marker and hence a 675 bp gene fragment was studied. A total of 352 T. navalis specimens from 13 different sampling sites distributed across Central Europe were examined. Subsequently, various population genetic indices including FST values and an AMOVA analysis were applied for the description of the population structure. To visualize the distribution of haplotypes at the different sampling sites two median-joining networks were calculated. In addition, the past demographic structure of the T. navalis population was analyzed, among others by calculating Tajima's D, Fu's F and the mismatch distribution. Finally, all computations of the population genetic indices could not reveal differentiated populations or any kind of distinct population structure in T. navalis. The network analyses revealed “star-like” patterns without differentiated substructures or demes. Therefore, it can be assumed that a sudden expansion of this species took place without any indications of neither a bottleneck nor a founder effect for the study area. The results of this study support the concept of a regional panmictic population in the waters of Central Europe with unhindered migration of individuals (e.g., via pelagic larvae between the various sampling sites as reflected by a high gene flow.

  17. Měkkýši Národní přírodní rezervace Soos Molluscs (Mollusca of the Soos National Nature Reserve

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    Jitka Horáčková

    2012-12-01

    Full Text Available The Soos National Nature Reserve nearby Františkovy Lázně Town (Western Bohemia, Czech Republic is a spectacular peatbog site with the occurrence of fens on numerous mineral spring effluents, emanations of pure carbon dioxide in mofettes (i.e. false mud volcanoes, parts with saltwater wetlands, and diatomite mantel in its central part. These natural conditions affect general character of all habitats, vegetation and malacocoenoses in the reserve. Altogether, 31 mollusc species were found there, but only two of them are considered as near threatened (Pisidium obtusale and Vertigo substriata. The majority of recorded assemblage was composed of common and generalist mollusc species.

  18. First report of Temnocephala haswelli (Platyhelminthes: Temnocephalida in Pomacea canaliculata (Mollusca: Ampullariidae from Brazil: description update based on specimens from the state of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Samantha A. Seixas

    2010-06-01

    Full Text Available The impact of the discovery of Temnocephala haswelli Ponce de Léon, 1989, described as ectosymbionts of ampullariid apple snails outside of Uruguay, motivated us to collect a large number of specimens of Pomacea canaliculata (Lamarck, 1822 from several localities in the southern portion of the state of Rio Grande do Sul. This species was recorded three times after its description: in a study of chromosomes, in a study about the ultrastructure of the collar receptor cells, and in a study of the Haswell glands, all conducted in Uruguay. A total of 301 specimens of P. canaliculata were collected from 1999 to 2007. Temnocephalans found in the pallial cavity were identified as T. haswelli, which occurred in single infestations or concurrently with Temnocephala iheringi Haswell, 1893. Helminths usually showed a light-orange body pigmentation and conspicuous, intense red-eye pigment. Many taxonomic characters evidenced by several techniques were documented photographically for the first time. The typical curved cirrus, approximately 90°, typical of the species, showed some variation in the width of the shaft base, whereas the first longitudinal row of spines of the introvert appeared with shorter spines. The vagina was found to be thick-walled, but not very muscular, and to have a single, large and slightly asymmetrical sphincter, with the posterior portion of slightly larger diameter. Eggs were observed in the umbilicus and along the suture, but predominantly in the body whorl of the shell. Egg peduncles were found to be very short or, most of the time, the eggs were sessile, always with a long apical filament. The rounded shape of the dorsolateral 'excretory' syncytial epidermal plates had external margins reaching the ventrolateral region of the body and eccentric nephridiopores. This is the first record of the species outside Uruguay and in Brazil.

  19. Intra-specific variability in life-history traits of Anadara tuberculosa (Mollusca: Bivalvia) in the mangrove ecosystem of the Southern coast of Ecuador.

    Science.gov (United States)

    Flores, Luis; Licandeo, Roberto; Cubillos, Luis A; Mora, Elba

    2014-06-01

    Anadara tuberculosa is one of the most important bivalves along the Western Pacific coast because of its commercial value. Nevertheless, the variability in growth, long-life span, natural mortality and reproductive parameters of this mangrove cockle has not yet been described. The aim of this study was to analyze these life-history traits in three areas of the Southern coast of Ecuador. Empirical and length-based methods were used to estimate these biological parameters. Body size data were collected from the commercial fishery between 2004 and 2011 in landing ports near to the Archipelago of Jambeli [Puerto Bolivar (PB), Puerto Jeli (PJ) and Puerto Hualtaco (PH)]. The von Bertalanffy growth parameters for combined sex were estimated between 70.87 to 93.45mm for L(infinity) and 0.22 to 0.80/year for k. The growth indices (PHI') ranged from 3.17 to 3.85, while the overall growth performance (OGP) ranged from 5.03 to 5.82. The mean of long-life span (t(max)), size and age at maturity (L50% and t50%) were estimated in 7.71 +/- 2.53 years, 39.13 +/- 2.24mm and 1.46 +/- 0.56 years for PB; 9.51 +/- 2.85 years, 37.78 +/- 1.95mm and 1.37 +/- 0.41 years for PJ and 5.81 +/- 2.11 years, 39.73 +/- 3.31mm and 0.94 +/- 0.41 years for PH. Natural mortality (M) ranged from 0.46 to 1.28/year. We concluded that significant intra-specific variation was observed in a temporal scale in PHI' and OGP indices as well as L50% and M. Therefore, temporal changes in these life-history traits should be taken into account when assessing the status of the mangrove cockle fishery.

  20. Registro de Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda no Brasil: caramujo hospedeiro intermediário da angiostrongilíase

    Directory of Open Access Journals (Sweden)

    Horácio Manuel Santana Teles

    1997-06-01

    Full Text Available A introdução de Achatina fulica é assinalada em Itariri, SP, Brasil. Essa espécie de caramujo terrestre foi importada para cultivo, visando à comercialização para consumo humano como "escargot". O encontro de exemplares em vida livre mostra a dispersão de A. fulica e, conseqüentemente, o risco de transmissão de Angiostrongylus cantonensis, nematóide parasita do homem e de outros vertebrados. Além disso, o caramujo é uma praga importante da agricultura.

  1. Registro de Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda no Brasil: caramujo hospedeiro intermediário da angiostrongilíase

    Directory of Open Access Journals (Sweden)

    Santana Teles Horácio Manuel

    1997-01-01

    Full Text Available A introdução de Achatina fulica é assinalada em Itariri, SP, Brasil. Essa espécie de caramujo terrestre foi importada para cultivo, visando à comercialização para consumo humano como "escargot". O encontro de exemplares em vida livre mostra a dispersão de A. fulica e, conseqüentemente, o risco de transmissão de Angiostrongylus cantonensis, nematóide parasita do homem e de outros vertebrados. Além disso, o caramujo é uma praga importante da agricultura.

  2. Genetic diversity and population genetic analysis of Donax vittatus (Mollusca: Bivalvia) and phylogeny of the genus with mitochondrial and nuclear markers

    Science.gov (United States)

    Fernández-Pérez, Jenyfer; Froufe, Elsa; Nantón, Ana; Gaspar, Miguel B.; Méndez, Josefina

    2017-10-01

    In this study, the genetic diversity of Donax vittatus across the Iberian Peninsula was investigated using four mitochondrial (COI, Cytb, 16S F and M types) and three nuclear (H3, 18S and 28S) genes. These same molecular markers were also sequenced in D. semistriatus and D variegatus to address the phylogenetic relationships of the species of the genus Donax common along the European coasts. Our results showed high haplotype diversity in combination with a low nucleotide diversity and a star-shaped network with a predominant haplotype, indicating a recent population expansion for the examined sampling sites of D. vittatus. Furthermore, analyses of population differentiation performed with COI mitochondrial marker, including global FST estimation and pairwise FST values, indicated the non-existence of significant genetic structure in D. vittatus of Northwest Iberian populations. Because these localities show a high genetic similarity, we suggest that D. vittatus could be a potentially alternative exploitable resource, as complement to the D. trunculus fisheries, whose natural stocks have decreased dramatically in some areas. Furthermore, we present for the first time, evidence of DUI in the clams D. vittatus and D. semistriatus.

  3. Evaluation of the levels of Br, Cl, K, Mg, Mn and V in Perna perna Mussels (Linnaeus, 1758: Mollusca, Bivalvia) collected in coast of Sao Paulo, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Daniele; Vasconcellos, Marina B.A.; Saiki, Mitiki; Catharino, Marilia G.M.; Moreira, Edson G., E-mail: danyseo@uol.com.br, E-mail: mbvascon@ipen.br, E-mail: mitiko@ipen.br, E-mail: mgcatharino@uol.com.br, E-mail: emoreira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Sousa, Eduinetty C.P.M. de, E-mail: edvinett@usp.br [Universidade de Sao Paulo (IO/USP), Sao Paulo, SP (Brazil). Instituto Oceanografico. Laboratorio de Ecotoxicologia Marinha e Microfitobentos

    2013-07-01

    In this study the content of Br, Cl, K, Mg, Mn and V was evaluated in samples of Perna perna mussels collected in coastal regions of Sao Paulo (Ponta de Itaipu and Palmas Island, in Santos) subjected to anthropogenic contamination, to compare these values with those of mussels from reference site of Cocanha Beach (in Caraguatatuba). The mussels were collected seasonally from September 2008 to July 2009. They were cleaned, ground, homogenized, lyophilized and then analyzed by Instrumental Neutron Activation Analysis (INAA). The INAA procedure consisted in the irradiation of the samples and synthetic elemental standards for 8 and 10 s, under a thermal neutron flux of 6.6 x 10{sup 12} n cm{sup -2} s{sup -1} in the IEA-R1 nuclear research reactor. For quality control of analytical results, certified reference materials NIST 1566b Oyster Tissue and NIST 2876 Mussel Tissue were analyzed and their results indicated good accuracy. The ranges of concentrations (dry basis) of the elements obtained in mussels collected for the four seasons of the year were: 173.80 to 358.99 mg kg{sup -1} for Br; 45658 ± 1811 to 109166 ± 824 mg kg{sup -1} for Cl; 7043 ± 856 to 12506 ± 675 mg kg{sup -1} for K; 2774 ± 211 to 5691 ± 717 mg kg{sup -1} for Mg; 7.01 ± 0.30 to 29.74 ± 3.32 mg kg{sup -1} for Mn and 0.77 ± 0.02 to 3.43 ± 0.28 mg kg{sup -1} for V. The seasonal and spatial variations of these element concentrations were in this study. (author)

  4. Pleurolucina from the western Atlantic and eastern Pacific Oceans: a new intertidal species from Curaçao with unusual shell microstructure (Mollusca, Bivalvia, Lucinidae

    Directory of Open Access Journals (Sweden)

    Emily A. Glover

    2016-09-01

    Full Text Available A new shallow water species of the lucinid bivalve Pleurolucina is described from Curaçao in the southern Caribbean Sea and compared with known species of the genus from the western Atlantic and eastern Pacific Oceans. Although confused with the Floridian species P. leucocyma, it is most similar to the eastern Pacific P. undata. As in all studied lucinids, the new species possesses symbiotic bacteria housed in the ctenidia. The shell microstructure is unusual with repeated and intercalated conchiolin layers that have sublayers of ‘tulip-shaped’ calcareous spherules. Predatory drillings by naticid gastropods frequently terminate at the conchiolin layers.

  5. Molluscan Evolutionary Development

    DEFF Research Database (Denmark)

    Wanninger, Andreas Wilhelm Georg; Koop, Damien; Moshel-Lynch, Sharon

    2008-01-01

    Brought together by Winston F. Ponder and David R. Lindberg, thirty-six experts on the evolution of the Mollusca provide an up-to-date review of its evolutionary history. The Mollusca are the second largest animal phylum and boast a fossil record of over 540 million years. They exhibit remarkable...

  6. Bioaccumulation and elimination of {sup 60} Co and {sup 137} Cs by Anomalocardia brasiliana (Gmelin, 1791) (Mollusca bivalvia). Remobilization of {sup 60} Co, retained in marine sediment by microbial activity; Bioacumulacao e eliminacao de {sup 60}Co e {sup 137}Cs por anomalocardia brasiliana (Gmelin, 1791) (Mollusca bivalvia). Remobilizacao de {sup 60}Co retido em sedimento marinho por atividade microbiana

    Energy Technology Data Exchange (ETDEWEB)

    Mayr, L M

    1984-05-01

    It was studied the capacity of a bi valve mollusc Anomalocardia brasiliana, which lives in the local bottom sediment, to remobilize {sup 60} Co previously sorbed in the sediment. Laboratory experiments demonstrated that the transference of {sup 60} Co from the sediment to the animal was insignificant (bioaccumulation factor (BF) of the order of 10{sup -3}). At the same time, the capacity of microorganisms, present in the bottom sediment, to remobilize {sup 60} Co was studied. The results showed that this via of transference was important, considering the much greater microorganism biomass in relation to the biomass of bentonic organisms, as a whole. For {sup 137} Cs the determined BF from water to the animal was 2.2. and, as in the case of {sup 60} Co, the soft tissues concentrated more {sup 137} Cs than shell. Remaining viscera showed the highest BFs. In another series of experiments, the loss of {sup 60} Co or {sup 137} Cs, previously accumulated by A. brasiliana, was followed in aquaria with or without sediment and the respective biological half-lives were calculated. Soft tissues retained {sup 60} Co longer (biological half-life = 117 days) than shells, whereas for {sup 137} Cs the opposite was observed and shells showed a biological half life of 38.5 days. The low values of {sup 60} Co and {sup 137} Cs BF{sub S} do not allow to classify A. brasiliana as good biological indicator for pollution by there radionuclides. However since A brasiliana is consumed by the local population and is commercialized to other areas, it was recommended that its contamination by {sup 60} Co or {sup 137} Cs should be monitored. (author).

  7. Occurrence of Aelurostrongylus abstrusus (Railliet, 1898 larvae (Nematoda: Metastrongylidae infecting Achatina (Lissachatina fulica Bowdich, 1822 (Mollusca: Gastropoda in the Amazon region Ocorrência de Aelurostrongylus abstrusus (Railliet, 1898 (Nematoda: Metastrongylidae infectando o Achatina (Lissachatina fulica Bowdich, 1822 (Mollusca: Gastropoda na região amazônica

    Directory of Open Access Journals (Sweden)

    Sanny Maria de Andrade-Porto

    2012-06-01

    Full Text Available Achatina fulica or "giant African snail" is an exotic species, considered to be one of the world's hundred most invasive species, causing serious environmental damages. In the present study we report, for the first time, the occurrence of Aelurostrongylus abstrusus infecting A.fulica in the Amazon region. This nematode is described parasitizing mainly the pulmonary system of felines, which causes "aelurostrongilose", also known as feline cardio-pulmonary strongyloidosis. New morphometric data of third stage larvae are presented herein. The present study demonstrated that 40% of all the snails were infected by A. abstrusus. Achatina fulica specimens were collected from three different areas in Manaus namely: rural; east and west areas. The east area presents the highest prevalence of 80%. The large number of A.fulica found in inhabited areas increases the chances of emergent zoonoses, which highlights the need of further studies so as to better control this disease.Achatina fulica ou "caramujo africano" é uma espécie exótica, considerada uma das cem piores espécies invasoras do mundo, causando sérios danos ambientais. No presente estudo foi registrado, pela primeira vez, a ocorrência do Aelurostrongylus abstrusus infectando o A.fulica na região amazônica. Esse nematóide é descrito parasitando principalmente o sistema pulmonar de felinos, causando a "aelurostrongilose", também conhecida como estrongiloidose cardio-pulmonar felina. Novos dados morfométricos de larvas de terceiro estágio são apresentados. Dos 45 caramujos coletados, 40% estavam infectados por larvas de A. abstrusus. Especimens de Achatina fulica foram coletados em três áreas da cidade de Manaus: rural, leste e oeste. A zona leste apresentou a maior prevalência de 80%. O grande número de A.fulica encontrado em áreas habitadas aumenta as chances de ocorrência de zoonoses emergentes e destaca a necessidade de mais estudos para o melhor controle da doença.

  8. Potentiality of Achatina fulica Bowdich, 1822 (Mollusca: Gastropoda) as intermediate host of the Angiostrongylus costaricensis Morera & Céspedes 1971 Achatina fulica Bowdich, 1822 (Mollusca: Gastropoda) como hospedeiro intermediário potencial do Angiostrongylus costaricensis Morera & Céspedes 1971

    OpenAIRE

    Omar dos Santos Carvalho; Horácio MS Teles; Ester Maria Mota; Cristiane Lafetá Gomes Furtado de Mendonça; Henrique Leonel Lenzi

    2003-01-01

    Samples of Achatina fulica were experimentally infected with Angiostrongylus costaricensis larvae, etiological agent of abdominal angiostrongyliasis, showing that A. fulica is susceptible to the parasite. Achatina fulica may be a risk to urbanization of abdominal angiostrongyliasis presumably due to its high proliferation, continuous dispersion and remarkable adaptation in several Brazilian towns.Exemplares de Achatina fulica foram experimentalmente infectados com larvas de Angiostrongylus co...

  9. Ciclo gametogênico e comportamento reprodutivo de Iphigenia brasiliana (Mollusca, Bivalvia, Donacidae no estuário do rio Subaé, Baía de Todos os Santos, Bahia, Brasil Gametogenic cycle and reproductive behavior of Iphigenia brasiliana (Mollusca, Bivalvia, Donacidae in the Subaé river estuary, Todos os Santos Bay, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia P. Silva

    2012-12-01

    Full Text Available Este estudo teve como objetivos descrever o ciclo gametogênico e o comportamento reprodutivo da população de Iphigenia brasiliana (Lamarck,1818 no estuário do rio Subaé, Baía de Todos os Santos, Bahia. Os bivalves foram coletados de novembro de 2001 a novembro de 2002. Um total de 244 espécimes foi medido (eixo anteroposterior, eviscerado, fixado, desidratado e incluído em parafina. O estudo histológico das gônadas foi realizado através de cortes seriados do tecido gonadal, de 5 mm de espessura, e corados pela HE. O tamanho médio mínimo da primeira maturação sexual (Lpm foi estimado a partir da distribuição das frequências relativas de jovens e adultos, por classe de comprimento dos indivíduos. As frequências relativas dos sexos em cada estádio de desenvolvimento foram consideradas conjuntamente para a análise do comportamento reprodutivo da população, e, em separado, para avaliar a sincronia do ciclo sexual entre machos e fêmeas. Foi observada uma variação de tamanhos entre 9,1 e 66,6 mm, com comprimento médio de 50,2 mm. O estudo não demonstrou diferença significativa entre os tamanhos de machos e fêmeas. Não foi possível observar a diferenciação de sexos em 2,1% dos indivíduos analisados. 51,6% dos indivíduos foram identificados como machos (M e 46,3% como fêmeas (F, não sendo constatadas diferenças significativas entre o número médio de machos e fêmeas, resultando numa proporção de M:F de 1,1:1. O Lpm foi estimado em 11,4 mm, mas apenas ao alcançarem comprimento médio de 34,4 mm, todos os indivíduos foram considerados adultos. Foram caracterizados quatro estádios de evolução do desenvolvimento gonadal em fêmeas e machos. A análise dos diferentes estádios permitiu a observação dos fenômenos de atresia e inversão sexual em fêmeas. O ciclo reprodutivo apresentou eliminação contínua de gametas, com maiores intensidades reprodutivas nos meses de novembro de 2001 a abril de 2002 e, também, no mês de outubro de 2002.This study aimed to describe the gametogenic cycle and reproductive behavior of the population of Iphigenia brasiliana (Lamarck, 1818 in the estuary of the Subaé river, Todos os Santos Bay, Bahia. The bivalves were collected from November 2001 to November 2002. A total of 244 specimens was measured (anteroposterior axis, gutted, fixed, dehydrated and embedded in paraffin. The histology of the gonads was performed by 5 mm thick serial sections of gonadal tissue, and stained with HE. The length at the beginning of gonadal maturation (Lpm was estimated from the distribution of the relative frequencies of youth and adults, by length class of individuals. The relative frequencies of the sexes at each stage of development were considered together for the analysis of the reproductive behavior of the population, and, separately, to assess the sexual cycle synchrony between males and females. We observed a variation of sizes between 9.1 and 66.6 mm, with a mean length of 50.2 mm. The study showed no significant difference between the sizes of males and females. There was no evidence of gender differentiation in 2.1% of subjects analyzed. 51.6% of subjects were identified as males (M and 46.3% as females (F, without significant differences among average number of male and female, resulting in the proportion of M:F ratio of 1,1:1. Lpm was estimated at 11.4 mm, but only to achieve average length of 34.4 mm, all subjects were considered adults. We characterized four stages of evolution of gonadal development in females and males. Analysis of different stages allowed the observation of the atresia phenomena and sex reversal in females. The reproductive cycle presents continuous elimination of gametes, with higher reproductive intensities in the months of November 2001 to April 2002 and also in October 2002.

  10. Ciclo gametogênico e comportamento reprodutivo de Iphigenia brasiliana (Mollusca, Bivalvia, Donacidae no estuário do rio Subaé, Baía de Todos os Santos, Bahia, Brasil Gametogenic cycle and reproductive behavior of Iphigenia brasiliana (Mollusca, Bivalvia, Donacidae in the Subaé river estuary, Todos os Santos Bay, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia P. Silva

    2012-01-01

    Full Text Available Este estudo teve como objetivos descrever o ciclo gametogênico e o comportamento reprodutivo da população de Iphigenia brasiliana (Lamarck,1818 no estuário do rio Subaé, Baía de Todos os Santos, Bahia. Os bivalves foram coletados de novembro de 2001 a novembro de 2002. Um total de 244 espécimes foi medido (eixo anteroposterior, eviscerado, fixado, desidratado e incluído em parafina. O estudo histológico das gônadas foi realizado através de cortes seriados do tecido gonadal, de 5 mm de espessura, e corados pela HE. O tamanho médio mínimo da primeira maturação sexual (Lpm foi estimado a partir da distribuição das frequências relativas de jovens e adultos, por classe de comprimento dos indivíduos. As frequências relativas dos sexos em cada estádio de desenvolvimento foram consideradas conjuntamente para a análise do comportamento reprodutivo da população, e, em separado, para avaliar a sincronia do ciclo sexual entre machos e fêmeas. Foi observada uma variação de tamanhos entre 9,1 e 66,6 mm, com comprimento médio de 50,2 mm. O estudo não demonstrou diferença significativa entre os tamanhos de machos e fêmeas. Não foi possível observar a diferenciação de sexos em 2,1% dos indivíduos analisados. 51,6% dos indivíduos foram identificados como machos (M e 46,3% como fêmeas (F, não sendo constatadas diferenças significativas entre o número médio de machos e fêmeas, resultando numa proporção de M:F de 1,1:1. O Lpm foi estimado em 11,4 mm, mas apenas ao alcançarem comprimento médio de 34,4 mm, todos os indivíduos foram considerados adultos. Foram caracterizados quatro estádios de evolução do desenvolvimento gonadal em fêmeas e machos. A análise dos diferentes estádios permitiu a observação dos fenômenos de atresia e inversão sexual em fêmeas. O ciclo reprodutivo apresentou eliminação contínua de gametas, com maiores intensidades reprodutivas nos meses de novembro de 2001 a abril de 2002 e, também, no mês de outubro de 2002.This study aimed to describe the gametogenic cycle and reproductive behavior of the population of Iphigenia brasiliana (Lamarck, 1818 in the estuary of the Subaé river, Todos os Santos Bay, Bahia. The bivalves were collected from November 2001 to November 2002. A total of 244 specimens was measured (anteroposterior axis, gutted, fixed, dehydrated and embedded in paraffin. The histology of the gonads was performed by 5 mm thick serial sections of gonadal tissue, and stained with HE. The length at the beginning of gonadal maturation (Lpm was estimated from the distribution of the relative frequencies of youth and adults, by length class of individuals. The relative frequencies of the sexes at each stage of development were considered together for the analysis of the reproductive behavior of the population, and, separately, to assess the sexual cycle synchrony between males and females. We observed a variation of sizes between 9.1 and 66.6 mm, with a mean length of 50.2 mm. The study showed no significant difference between the sizes of males and females. There was no evidence of gender differentiation in 2.1% of subjects analyzed. 51.6% of subjects were identified as males (M and 46.3% as females (F, without significant differences among average number of male and female, resulting in the proportion of M:F ratio of 1,1:1. Lpm was estimated at 11.4 mm, but only to achieve average length of 34.4 mm, all subjects were considered adults. We characterized four stages of evolution of gonadal development in females and males. Analysis of different stages allowed the observation of the atresia phenomena and sex reversal in females. The reproductive cycle presents continuous elimination of gametes, with higher reproductive intensities in the months of November 2001 to April 2002 and also in October 2002.

  11. Distribución temporal de larvas de Mytilus chilensis (Hupé, 1954 (Mollusca: Mytilidae, en el mar interior de Chiloé, sur de Chile Temporal distribution of larvae of Mytilus chilensis (Hupé, 1854 (Mollusca: Mytilidae, in the interior sea of Chiloé, southern Chile

    Directory of Open Access Journals (Sweden)

    Miguel Avendaño

    2011-11-01

    Full Text Available Entre septiembre 2007 y marzo 2008, en Quillaipe, Metri, Sotomo, Canutillar y Pichicolo (mar interior de Chiloé, se determinó mensualmente la presencia larval de M. chilensis, mediante arrastres verticales de plancton, en una columna de 0-7,5 m y paralelamente se determinó histológicamente el estado reproductivo de ejemplares adultos. Se detectó permanentemente la presencia de larvas en los cinco sitios estudiados, con un significativo incremento entre octubre y diciembre, superando en Canutillar 49 mil larvas por m-3, sitio que junto a Sotomo registraron las mayores densidades. El análisis de cohortes mostró una similitud de los grupos larvales presentes en los diferentes sitios a partir de septiembre, acentuándose durante noviembre y diciembre, así como una permanente aparición de cohortes en estadios iniciales. En contraste con estos resultados, el proceso reproductivo de M. chilensis en estos sitios, se manifestó de enero a marzo. Se discute que los desoves registrados en estos sitios, no serían responsables de la presencia de las larvas, actuando en consecuencia como áreas receptoras, y de retención de larvas provenientes de otros sitios. Estos resultados sugieren la necesidad de profundizar conocimientos biológicos y ecológicos en áreas de distribución de la especie, así como de dinámica larval y post-larval para identificar áreas exportadoras y de retención, para contribuir a un manejo eficiente y optimizar la captación de semilla.The larval presence of M. chilensis was determined monthly from September 2007 to March 2008, in Quillaipe, Metri, Sotomo, Canutillar, and Pichicolo (interior sea of Chiloé using vertical plankton trawls through a water column from 0 to 7.5 m. At the same time, the reproductive stage of adult individuals was determined histologically. Larvae were detected continuously at the five study sites, with a significant increase from October to December, exceeding 49 thousand per m-3 at Canutillar where, along with Sotomo, the greatest densities were recorded during the study. Cohort analysis showed a similarity in the larval cohorts present at the different sites from September onwards; this was accentuated in November and December, as was the constant appearance of cohorts in the initial stages. In contrast with these results, the reproductive process of M. chilensis at these sites occurred from January to March. Whether or not the spawning recorded at these sites is responsible for the observed larvae is a matter of debate, as the sites may receive and retain larvae exported from other sites. These results suggest a need to compile further biological and ecological knowledge on the areas where this species is distributed and its larval and post-larval dynamics in order to identify exporting and retention areas and thereby contribute to efficient management and the optimization of spat collection.

  12. Influência do substrato sobre a reprodução de Subulina octona (Brugüière (Mollusca, Subulinidae, sob condições de laboratório Influence of substrate on reproduction of Subulina octona (Brugüière (Mollusca, Subulinidae, under laboratorial conditions

    Directory of Open Access Journals (Sweden)

    Sthefane D'ávila

    2005-03-01

    Full Text Available O objetivo deste trabalho foi determinar se o substrato influencia a reprodução de indivíduos da espécie Subulina octona (Brugüière, 1789, mantidos em três diferentes substratos: areia, argila e terra vegetal. Foram analisados os seguintes parâmetros: número de ovos produzidos a cada evento reprodutivo, tempo para o alcance da maturidade sexual, idade dos indivíduos a cada evento reprodutivo, intervalo entre eventos reprodutivos, número total de ovos por indivíduo, número total de eventos reprodutivos por indivíduo e aumento do número de ovos de um evento para o subseqüente. O substrato influenciou o tempo necessário para o alcance da maturidade sexual, bem como o tempo para a realização dos eventos reprodutivos subseqüentes ao primeiro, a produção de ovos, o número total de ovos produzidos e de eventos reprodutivos de S. octona. Indivíduos mantidos em caixa com terra vegetal levaram mais tempo para realizar o primeiro, segundo, terceiro e quarto evento reprodutivo, produziram menos ovos, no segundo, terceiro e quarto evento e apresentaram um intervalo maior entre o primeiro e segundo evento.The influence of substrate on reproduction of Subulina octona (Brugüière, 1789, reared in sand, clay and humus, was investigated under laboratorial conditions. There were significant differences in onset of sexual maturity, egg production, shell length and aging in each reproductive event, total number of eggs produced and total number of reproductive events. The individuals reared in humus spent more time to reach sexual maturity, as well as to accomplish the subsequent reproductive events. Moreover, produced fewer eggs in the second, third and fourth ovipositions and exhibited a longer interval between the first and second reproductive events. After 120 days of experiment such individuals had produced fewer eggs, and performed fewer reproductive events, when compared with those kept in sand and clay. There was a progressive decline in egg number increase with time. In this study was also observed that S. octona of different developmental stages fed on substrate and the molluscs reared in humus consumed less food. This is probably due to the fact that humus is more likely to be take as food resource. So that, the snails reared in humus tend to consume more substrate and less ration, obtaining less proteins, carbohydrates and calcium than those snails reared in sand and clay. This low intake of ration might have negative effects over reproduction of the snails.

  13. Detection limits of absorbed dose of ionizing radiation in molluscan shells as determined by e.p.r. spectroscopy

    International Nuclear Information System (INIS)

    Stachowicz, W.; Michalik, J.; Burlinska, G.; Sadlo, J.; Dziedzic-Goclawska, A.; Ostrowski, K.

    1995-01-01

    The exposure of waters to ionizing radiation from radionuclides imprisoned in dumped nuclear waste containers, freed in nuclear submarine accidents or released in underwater magma eruptions are difficult to be evaluated by conventional radiometric methods. Ionizing radiation evokes stable paramagnetic centers in crystalline lattice of mineral components in bone skeletons of mammals and fishes as well as in exoskeletons of mollusca. They give rise in e.p.r. to specific, extremely stable signals which are proposed to be applied as indicators of radiation exposure levels. In the present study the e.p.r. detection limits of the dose of ionizing radiation absorbed in shells of fresh water and marine mollusca (selected species) have been estimated. It has been found that with fresh water mollusca the dose of 1-2 Gy can be detected, while the sea water mollusca by one order of magnitude lower, i.e. about 0.1 Gy. (author)

  14. Měkkýši údolí Vltavy (Čechy)

    Czech Academy of Sciences Publication Activity Database

    Horáčková, J.; Ložek, V.; Beran, L.; Juřičková, L.; Podroužková, Š.; Peterka, Jiří; Čech, Martin

    2014-01-01

    Roč. 13, - (2014), s. 12-105 ISSN 1336-6939 Institutional support: RVO:60077344 Keywords : faunistics * inventory * Mollusca * river floodplain * Lucilla scintilla * Margaritifera margaritifera Subject RIV: EH - Ecology, Behaviour

  15. Plankton composition in the coastal waters between Jaigarh and Rajapur along west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, S.R.S.; Achuthankutty, C.T.; Nair, V.R.; Devassy, V.P.

    , Mollusca, Decapoda, Chaetognatha, Tunicata and fish eggs and larvae were the major groups in the zooplankton population. The highest secondary production values were obtained off Ratnagiri and the average production for the Konkan coastal waters was found...

  16. Molluscan shell evolution with review of shell calcification hypothesis

    Czech Academy of Sciences Publication Activity Database

    Furuhashi, T.; Schwarzinger, C.; Mikšík, Ivan; Smrž, Miloslav; Beran, A.

    2009-01-01

    Roč. 154, č. 3 (2009), s. 351-371 ISSN 1096-4959 Institutional research plan: CEZ:AV0Z50110509 Keywords : mollusca * shell * biomineralization Subject RIV: CE - Biochemistry Impact factor: 1.607, year: 2009

  17. Early development of the aplacophoran mollusc Chaetoderma

    DEFF Research Database (Denmark)

    Nielsen, Claus; Haszprunar, Gerhard; Ruthensteiner, Bernhard

    2007-01-01

    The early development of the trochophore larva of the aplacophoran Chaetoderma nitidulum (Mollusca: Caudofoveata = Chaetodermomorpha) is described using scanning and transmission electron microscopy and using fluorescence staining and confocal laser scanning microscopy of the muscle system...

  18. Use of Population Parameters in Examining Changes in the Status of the Short-Necked Clam Paphia undulata Born, 1778 (Mollusca, Pelecypoda: Veneridae in Coastal Waters of Southern Negros Occidental

    Directory of Open Access Journals (Sweden)

    Anabelle del Norte Campos

    2010-06-01

    Full Text Available Growth, recruitment, mortality and exploitation rate of the short-necked clam Paphia undulata (Born, 1778 were studied in southern Negros Occidental waters between August 2007 and July 2008 from length-frequency data derived from catches of divers, to be able to compare with earlier data derived and analyzed 13 years ago by Agasen et al. (1998. Both sets of data were analyzed using the FiSAT software (Gayanilo & Pauly, 1997. The asymptotic shell length (S¥ = 79 mm derived from the present data proved to be smaller compared to the earlier data (SL¥ = 81.5 mm due to the lack of bigger sizes in the present samples. The growth constant (K = 1.0 yr-1 was however comparable indicating it to be a more species-characteristic parameter. Two recruitment pulses for each study were derived and were found to be correlated with the spawning pattern in the species. The value of natural mortality (M = 1.57 yr-1 derived from bivalve literature, is deemed more appropriate compared to the earlier estimate (M = 2.89 yr-1 based on Pauly’s (1980 empirical equation developed for fish. Total mortality (Z values for both studies were comparable, but a higher level of fishing mortality (F = 4.61 yr-1 was estimated for the present data set, thus resulting likewise in a higher exploitation rate (E = 0.75. These, together with fishery information from an accompanying paper (Villarta & del Norte-Campos, 2010, not only validate the earlier findings of overexploitation due to lack of management, but reveal a worsening condition of the stock, most likely as a result of growth overfishing. Overexploitation can only be mitigated by imposing stringent restrictions in terms of the minimum size for exploitation (45 mm shell length and closed seasons during the spawning peak (August-November.

  19. Body size structure, biometric relationships and density of Chiton albolineatus (Mollusca: Polyplacophora) on the intertidal rocky zone of three islands of Mazatlan Bay, SE of the Gulf of California

    OpenAIRE

    Flores-Campaña, Luis Miguel; Arzola-González, Juan Francisco; de León-Herrera, Ramón

    2012-01-01

    Populations of the polyplacophoran mollusk Chiton albolineatus were studied at 6 sites with different wave exposure of the rocky shores of 3 islands of Mazatlan Bay (southeastern side of the Gulf of California). This chiton species is endemic to the Mexican Pacific coast. Chitons were sampled on wave-exposed and wave-protected sites in the intertidal zone of these islands from January to December 2008 to determine its demographic patterns based on density and body size. Length (L), breadth (B...

  20. Density, size structure, shell orientation and epibiontic colonization of the fan mussel Pinna nobilis L. 1758 (Mollusca: Bivalvia in three contrasting habitats in an estuarine area of Sardinia (W Mediterranean

    Directory of Open Access Journals (Sweden)

    Piero Addis

    2009-03-01

    Full Text Available We investigated the spatial distribution, size structure, shell orientation and valve colonization by epibionts of the endangered Mediterranean bivalve Pinna nobilis in three continuous but different habitats in the Gulf of Oristano (Sardinia, western Mediterranean. The sampling stations chosen were: an estuarine area (E of coastal salt-marshes characterized by unvegetated sea-bottoms; and two areas in a seagrass meadow characterized by an extensive Posidonia oceanica meadow (Mw and patched mixed meadows of P. oceanica and Cymodocea nodosa (Me. We found significant differences in mean densities among stations and the highest value was found in the estuarine area. Shell orientation showed that there was uniform circular distribution of specimens in the Mw station and a unimodal distribution in the Me and E stations, where specimens were set at 0°N and 10°NNE, which is a pattern related to sea drift. Shell epibiosis displayed differences between habitats. The highest valve colonization was in the estuary, with filamentous dark algae and Ostrea edulis reaching almost 90 percent of shell coverage. This study provides new information on habitat preferences and data for assessing local populations of P. nobilis that is useful for its conservation and improving the knowledge of its ecology.

  1. Annotations to the figured scallops (Mollusca, Bivalvia, Pectinidae) in Gualtieri’s “Index Testarum Conchyliorum”, deposited in the Museo di Storia Naturale e del Territorio at Calci (Pisa, Italy)

    NARCIS (Netherlands)

    Dijkstra, H.H.

    2016-01-01

    An overview is given of the Pectinidae types present in the Gualtieri collection. In Gualtieri (1742) 46 figures (pl. 73 - 15 figs, pl. 74 - 25 figs, pl. 98 – 2 figs, and pl. 99 – 4 figs) show specimens of Pectinidae. Linnaeus (1758) referred to 10 Pectinidae species figured by Gualtieri. Of these,

  2. Freshwater Mussels (Mollusca: Bivalvia: Unionidae) of the Upper Mississippi River: Observations at Selected Sites Within the 9-Foot Navigation Channel Project for the St. Paul District, United States Army Corps of Engineers, 1977 - 1979. Volume II. Appendices.

    Science.gov (United States)

    1980-09-10

    as caz’nata A J T R H Ligwnia recta L. subrost rat a Carunculina parva Lampsilis terea L. higginsi L. radiata siliquoidea L. ovata ventricosa Plagio ...radiata siZiquc’idea 1 1 0.?2 X L. ovata ventricosa 2 2 0. 3 Plagio Za trique tra X Arcidens con fragosus 2 2 0.3 Lasmiqona camptlcnata L. cost ata L

  3. Catálogo de los Uniónidos (Mollusca, Unionidae de la península Ibérica conservados en el Museo Nacional de Ciencias Naturales (CSIC

    Directory of Open Access Journals (Sweden)

    Soriano, Óscar

    2001-06-01

    Full Text Available From the 1987, we are working in the recuration process of the collections from the Museo Nacional de Ciencias Naturales (MNCN. In 1999, among other achievements, 1357 specimens of unionids from the Iberian Peninsula have been catalogued; these specimens are from the collections of González Hidalgo, Paz y Membiela, Azpeitia, Álvarez, Cobos, etc. The habitats of the species of unionids experienced a gradual deterioration during the second half of the XXth century due to their relative intolerance to pollution. Actually, most collecting localities of the specimens in the MNCN are not suitable habitat for unionids today. The fast regression suffered by the Iberian species underscores the need to proceed to the recovery and the conservation of the aquatic ecosystems where species belonging to this family are present, before their total disappearance takes place. It is necessary to gather the information deposited in public and private collections, that could contribute to determine more accurately the past distribution of these species.

    Desde el año 1987 se están recuperando las colecciones del Museo Nacional de Ciencias Naturales. Durante 1999, entre otros trabajos, se han catalogado los 1363 ejemplares de uniónidos de la península Ibérica, que procedentes de las colecciones de González Hidalgo, Paz y Membiela, Azpeitia, Álvarez, Cobos, etc., se conservan en el museo. El progresivo deterioro que, en la segunda mitad del siglo XX, han tenido los hábitats de las especies de la familia que aquí tratamos, ha producido, su desaparición en gran parte de las localidades de las que se conserva representación en las colecciones del museo. La rápida regresión sufrida por las especies ibéricas, nos pone de manifiesto la necesidad de proceder a la recuperación y a la conservación de los ecosistemas acuáticos con presencia de especies pertenecientes a esta familia, antes de que se produzca su total desaparición. Por todo ello, se hace necesario conocer la información que se recoge en colecciones públicas o privadas y que podría contribuir a conocer la distribución que, en tiempos pasados, tenían estas especies.

  4. Fresh-Water Mussels (Mollusca: Bivalvia: Unionidae) of the Upper Mississippi River: Observations at Selected Sites within the 9-Foot Channel Navigation Project on Behalf of the U.S. Army.

    Science.gov (United States)

    1978-06-16

    Deertoe Ohovaria olivaria *Hjckorynut Glassback Eggshell Long ’Solid Actinonaias carinata *Mucket Mouket Mougat A. elipsiformie *Ellipse Liqumia recta...Catservatuls end Iited States Nepartmet of Agriculture, Soil Ctsraemtioa Service, Jeferson City* Missourl. Pp. I-ISO. Seshoala, A. V. 1941. Tapoles as

  5. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs ofLymnaea stagnalis andBithynia tentaculata (Mollusca).

    Science.gov (United States)

    Zivkovic, Danica; Créton, Robbert; Zwaan, Gideon; de Bruijn, Willem C; Dohmen, M René

    1990-11-01

    During extrusion of the first polar body in eggs ofLymnaea stagnalis andBithynia tentaculata a localized Ca 2+ /Mg 2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity was distributed in a polar fashion, along the cytoplasmic face of the plasma membrane. In the eggs ofLymnaea it was found only in the vegetal hemisphere, whereas inBithynia eggs it was localized both in the vegetal hemisphere and at the animal pole. This pattern of enzyme activity corresponds to the polar pattern of transcellular ionic currents measured with the vibrating probe, which we showed to be partially carried or regulated by calcium [Zivkovic and Dohmen (1989) Biol Bull (Woods Hole) 176 (Suppl):103-109]. The characteristics of the ATPase were studied using a variety of approaches such as ion and substrate depletions and substitutions, addition of specific inhibitors of ATPase activity, treatment with EDTA/EGTA and electron energy-loss spectrometry. The results indicate that, inLymnaea, there are at least two enzymatic entities. The first one is a Ca 2+ /Mg 2+ ATPase localized along the membrane and in the cortex of the vegetal hemisphere. The second one is a Ca 2+ -stimulated ATPase (calcium pump of the plasma membrane) localized in a small region of the membrane at the vegetal pole. We speculate that in the eggs ofLymnaea andBithynia a functional relationship exists between the plasma-membrane-associated ATPase activity and the transcellular ionic currents measured in the same region.

  6. Reações da espécie invasora Achatina fulica (Mollusca: Achatinidae à fatores abióticos: perspectivas para o manejo Reactions of the invasive alien species Achatina fulica to abiotic factors: perspectives for the management

    Directory of Open Access Journals (Sweden)

    Marta Luciane Fischer

    2009-09-01

    Full Text Available Achatina fulica Bowdich, 1822 is an african snail that is invasive in different parts of the world, being characterized mainly by its high adaptability. Our objective was to evaluate the influence of abiotic factors, such as temperature and substrate, on the egg eclosion, adult and juvenile reaction to different abiotics factors, and the resistance of A. fulica to popular methods of control. Three studies were made, including 19 laboratory experiments and observations of free animals in the municipal district of Guaraqueçaba, southern Brazil. Eggs were characterized as the most fragile phase, whereas the juveniles and adults were resistant to the immersion in fresh and salt water and little resistant to temperature variation and salt, using burying, aestivation, and muscular force as defense strategies. Those strategies should be considered in management actions and in orientating popular methods of control.

  7. Cuantificación de metales pesados en Anadara tuberculosa(Mollusca:bivalvia del estero Huaylá de Puerto Bolívar, por espectrofotometría de absorción atómica

    Directory of Open Access Journals (Sweden)

    Collaguazo-Collaguazo, Yadira

    2017-09-01

    Full Text Available The presence of heavy metals in bivalve molluscs implies a serious problem for the consumers health of this type of food. Therefore, the objective of the present investigation was to determine the presence of heavy metals in Anadara tuberculosa, mollusc of commercial importance at Puerto Bolívar, Ecuador. Atomic absorption spectrophotometry was the method used to quantify the concentration of heavy metals. The concentration of six metals was determined: lead (Pb, arsenic (As, mercury (Hg, cadmium (Cd, chromium (Cr and cobalt (Co. The average values obtained, expressed in mg.kg-1 were: Pb (7.52 ± 0.46; As (1.55 ± 0.14; Hg (364.38 ± 91.39; Cd (1.68 ± 0.28; Cr (3,89 ± 1,82 and Co (2,71 ± 0,34 in A. tuberculosa The results show that Pb, As, Cd, and Hg exceed the maximum permissible limits, mercury exceeds by more than 100 times the limit value. The smaller size (3-4 cm studied mollusc, has the capacity to bioaccumulate higher concentration of Pb, Cd and Cr.

  8. The Mass-Dimension Relationships in the Mussels Mytilus Galloprovincialis (Mollusca, Bivalvia from Different Phenotypical Groups in Periphyton Populations near Odessa Coast, the North-Western Part of Black Sea

    Directory of Open Access Journals (Sweden)

    Govorin I. A.

    2016-06-01

    Full Text Available The data of the size-mass indices in the mussels Mytilus galloprovincialis (Lamarck, 1819 from three phenotypic groups - brown, dark violet (black and “zebra” (brown with radial black stripes shells in the periphyton settlements on the concrete traverses near Odessa coast, the North-western part of Black Sea (Ukraine, in March-November 2014-2015 are presented. A comparative evaluation has been made on the relationships of total mass of the mollusks, wet and dry mass of their soft body and mass of the shells on the one hand, and the size of animals (length of its shells on the other hand, in the each of phenotypical groups from the five marine beach areas. It is shown, that in the marine areas with different degrees of isolation from the open sea by coast-protection engineering constructions, the mussels from different phenotypes have almost the same size-mass characteristics. Only the dry weight of soft animal body, which indicated to fatness of mollusk and therefore demonstrated his biological prosperity in specific hydrological conditions, can serve as a reliable criterion which can mark the shellfish habitats with different gradients of environmental factors.

  9. Ciclo gametogênico e comportamento reprodutivo de Iphigenia brasiliana (Mollusca, Bivalvia, Donacidae no estuário do rio Subaé, Baía de Todos os Santos, Bahia, Brasil

    Directory of Open Access Journals (Sweden)

    Patrícia P. Silva

    Full Text Available Este estudo teve como objetivos descrever o ciclo gametogênico e o comportamento reprodutivo da população de Iphigenia brasiliana (Lamarck,1818 no estuário do rio Subaé, Baía de Todos os Santos, Bahia. Os bivalves foram coletados de novembro de 2001 a novembro de 2002. Um total de 244 espécimes foi medido (eixo anteroposterior, eviscerado, fixado, desidratado e incluído em parafina. O estudo histológico das gônadas foi realizado através de cortes seriados do tecido gonadal, de 5 mm de espessura, e corados pela HE. O tamanho médio mínimo da primeira maturação sexual (Lpm foi estimado a partir da distribuição das frequências relativas de jovens e adultos, por classe de comprimento dos indivíduos. As frequências relativas dos sexos em cada estádio de desenvolvimento foram consideradas conjuntamente para a análise do comportamento reprodutivo da população, e, em separado, para avaliar a sincronia do ciclo sexual entre machos e fêmeas. Foi observada uma variação de tamanhos entre 9,1 e 66,6 mm, com comprimento médio de 50,2 mm. O estudo não demonstrou diferença significativa entre os tamanhos de machos e fêmeas. Não foi possível observar a diferenciação de sexos em 2,1% dos indivíduos analisados. 51,6% dos indivíduos foram identificados como machos (M e 46,3% como fêmeas (F, não sendo constatadas diferenças significativas entre o número médio de machos e fêmeas, resultando numa proporção de M:F de 1,1:1. O Lpm foi estimado em 11,4 mm, mas apenas ao alcançarem comprimento médio de 34,4 mm, todos os indivíduos foram considerados adultos. Foram caracterizados quatro estádios de evolução do desenvolvimento gonadal em fêmeas e machos. A análise dos diferentes estádios permitiu a observação dos fenômenos de atresia e inversão sexual em fêmeas. O ciclo reprodutivo apresentou eliminação contínua de gametas, com maiores intensidades reprodutivas nos meses de novembro de 2001 a abril de 2002 e, também, no mês de outubro de 2002.

  10. Redescription of Temnocephala iheringi (Platyhelminthes: Temnocephalida based on specimens from Pomacea canaliculata (Mollusca: Ampullariidae of the state of Rio Grande do Sul, Brazil: the possible type host and type locality

    Directory of Open Access Journals (Sweden)

    Samantha A. Seixas

    2010-04-01

    Full Text Available The original description of Temnocephala iheringi Haswell, 1893 was based on specimens collected by Hermann von Ihering from undetermined ampullariid apple snails, which at that time were identified as Ampullaria sp., and sent to William H. Haswell, with the type locality simply indicated as Brazil. The type specimens studied by Haswell were not found in the scientific collections of Brazil, Europe or Australia, and should be considered lost. In 1941, Pereira & Cuocolo collected specimens from apple snails, identified as Pomacea lineata (Spix in Wagner, 1827, at two localities (Guaicurús and Salobra in the state of Mato Grosso do Sul, central Brazil. These specimens could not be located either and should, thus, be considered lost as well. Pomacea canaliculata (Lamarck, 1822, the main host of T. iheringi in southern Brazil, is known to have a geographical distribution that reaches Uruguay and 400 km beyond the province of Buenos Aires, Argentina. Three hundred and one mollusks were collected from 1999 to 2007. Temnocephalans found in the pallial cavity presented a greenish body pigmentation (adults and lacked eye pigment of any color, including the red-eye pigment, typical of Neotropical species of Temnocephala Blanchard, 1849; straight cirrus, with a thick band at base of the introvert' swelling; and a single, circular, asymmetric vaginal sphincter, wider in diameter in the posterior portion. As the species occurs concurrently with two other species, at least in P. canaliculata from Rio Grande do Sul, the eggs of T. iheringi could not be reliably distinguished. A redescription of the species is provided. A comparison of data from the present work with those of earlier papers published on T. iheringi from Argentina showed that the Argentinean specimens had the smallest measurements.

  11. The introduction of Melanoides tuberculata (Mollusca: Thiaridae) to the island of Saint Lucia (West Indies) and its role in the decline of Biomphalaria glabrata, the snail intermediate host of Schistosoma mansoni.

    Science.gov (United States)

    Pointier, J P

    1993-06-01

    A malacological survey was carried out in May 1992 in the whole hydrographic system of Saint Lucia 11 years after the end of a biological control programme to eliminate Biomphalaria glabrata, the snail intermediate host of Schistosoma mansoni. A competitor snail, Melanoides tuberculata, was introduced to Saint Lucia in 1978 and field experiments in several habitats were conducted by Prentice between 1978 and 1986. At the present time M. tuberculata is the most common freshwater snail in Saint Lucia. The results of the survey, undertaken in sites where B. glabrata occurred in large populations in the past showed (i) the absence of the snail hosts from seven sites now extensively colonized by the competitor (ii) the presence of B. glabrata in low or very low densities in 17 sites together with the competitor and (iii) the presence of the intermediate hosts in large populations in only two sites where M. tuberculata was absent. These results confirm the positive results observed by Prentice. The presence of another planorbid snail, B. straminea, is reported for the first time in Saint Lucia.

  12. Variações no comprimento dos indivíduos de uma população do mexilhão dourado, Limnoperna fortunei (Mollusca: Bivalvia: Mytilidae, ao longo do ano, na Praia do Veludo, Lago Guaíba, Rio Grande do Sul, Brasil Length variation over a one-year period in specimens of the golden mussel, Limnoperna fortunei (Mollusca: Bivalvia: Mytilidae from Veludo Beach, Guaíba Lake, Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Cintia P. dos Santos

    2008-09-01

    Full Text Available The individual size of Limnoperna fortunei (Dunker, 1857 was evaluated twice a month, for a year, based on samples from Veludo Beach (30º12'35"S, 51º11'68"W in Guaiba Lake, southern Porto Alegre, Brazil. Physical and chemical data on water quality, such as temperature, transparency, depth, pH, dissolved oxygen, phosphorus, nitrogen, chlorophyll "a", and conductivity were also recorded. Adult samples were collected from underwater "sarandi" branches, Cephalanthus glabratus (Spreng K. Schum (Rubiaceae, an aquatic macrophyte available at each site. Adults placed on artificial substrates were also checked every six months. Data were analyzed by applying multivariate statistics techniques related to the physical and chemical variables of the water and the density of individuals to estimate the patterns of the individual growth over the year. The adults were separated into three groups according to length classes: G1, G2 and G3 (groups 1 through 3. These three groups are related to the differences in behavior, namely, the ability of locomotion and fixation capacity. Individuals from Group 1 (5 to 7 mm in length were the most abundant and were present in all the sampled months. Adults from artificial substrates were shown to display significant differences in seasonal growth and faster growth during spring and summer months.

  13. Mauro Dell’Ambrogio, the Swiss State Secretary for Education and Research (left), Rolf Heuer , CERN Director-General (centre), and Mark Muller, President of the Government of the Republic and Canton of Geneva and Head of the Department of Construction and Information Technology (right) at the opening of Building 42 on 11 February, 2011.

    CERN Multimedia

    Maximilien Brice

    2011-01-01

    CERN-HI-1102069 05: Représentant permenant de la Suisse auprès de l'Office des Nations Unies Ambassadeur Martinelli et le Directeur général du CERN R. Heuer. CERN-HI-1102069 14: J.Perret, Architecte; P.Fassnacht, Représentant des utilisateurs CERN et M. Poehler, Ingénieur CERN en charge du chantier.

  14. Book Review: Russia-Germany. Milestones of the Joint History in the Collective Memory. 20th Century / ed. by H. Muller, A. O. Chubaryan ; by the Decision of the Joint Commission on Studying the Modern History of the Russian-German Relations

    Directory of Open Access Journals (Sweden)

    Vashkau Nina Emilyevna

    2015-11-01

    Full Text Available This is a review of a Russian-German textbook that describes the events of the 20th century. The book has been created by the Common Board for Research on the History of the Russian-German Relationships and can be used as learning material in schools and universities of both countries.

  15. Characteristics and fabrication of Geiger-Mueller counters with thin walls made of treated magnesium - Note about the use of araldite; Caracteristiques et fabrication des compteurs Geiger-Muller a paroi mince en magnesium traite - Note sur l'utilisation de l'araldite

    Energy Technology Data Exchange (ETDEWEB)

    Charbonnel, A

    1949-03-01

    This report describes, first, the advantage of magnesium for the manufacturing of Geiger-Mueller counters: suitable for machining and polishing, but strong reactivity with the counter atmosphere in the case of magnesium-rich alloys. Thus, the inside wall of the counter (cylinder of 20 mm diameter and 6 cm length) requires a non-reactive protective coating with excellent sealing properties. The synthetic resin 'araldite' fulfills all these conditions. The second part of the report describes the different steps of the fabrication of magnesium wall counters: lathe work, machining down and chemical polishing of hulls, assembly, tight sealing, pumping, filling-up and control tests. The average service life of these counters is of about 4 months. A note about the use and properties (hardening, mechanical properties, resistance..) of araldite is given in appendix. (J.S.)

  16. Ocorrência no Brasil de Thiara (Melanoides tuberculata (O.F. Muller, 1774 (Gastropoda, Prosobranchia, primeiro hospedeiro intermediário de Clonorchis sinensis (Cobbold, 1875 (Trematoda, Plathyhelmintes Occurrence of Thiara (Melanoides tuberculata (O.F. Mullher, 1774 (Gastropoda, Prosobranchia in Brazil, first intermediate host of Clonorchis sinensis (Cobbold, 1875 (Trematoda, Plathyhelmintes

    Directory of Open Access Journals (Sweden)

    Jorge Faria Vaz

    1986-08-01

    Full Text Available Relata-se a introdução em nosso meio de Thiara (Melanoides tuberculata possivelmente anterior a 1967, quando pela primeira vez foi coletada em Santos. Essa espécie pode comportar-se como primeiro hospedeiro intermediário de Paragonimus westermani e de Clonorchis sinensis. Somente o último trematódeo tem alguma possibilidade de vir a parasitar o homem, em nosso meio.Introduction of Thiara (Melanoides tuberculata in Brazil, is reported. This introduction may go back prior to 1967 when some specimens were collected at Santos, S.Paulo (Brazil. T. (M. tuberculata is an intermediate host of Paragonimus westermani and Clonorchis sinensis, both pathogenic for man. Only this last trematode has some potential for human infection in Brazil.

  17. Determination of some fundamental characteristics of Geiger-Mueller counters. Applications to the study of delayed particles from cosmic-ray shower; Sur la determination de quelques caracteristiques fondamentales de compteurs de geiger-muller applications a l'etude des particules retardees des gerbes atmospheriques du rayonnement cosmique

    Energy Technology Data Exchange (ETDEWEB)

    Picard, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1954-06-15

    After some historic recalls, the different phases of discharge of a Geiger-Mueller counter is studied. It measures, by oscillograph method, the time between the flow of a particle through a determined area of the counter and the response of the associated amplifier. This time length is composed by the latency period and the delay itself which depends on the amplifier sensitivity. The selection of particles which generate a discharge in the studied counter is obtained with a two coincidence counters telescope in which the aperture is limited by four counters in anticoincidence with the first two counters. The measures have been done with different distance values and an overvoltage V{sub s} which was applied to the counter. The dead time of a GM counter is also measured with a delayed coincidences method. The counter pulses which supply the coincidence circuit are delivered directly or with a known and variable delay. This method allows also to study the spurious pulses which are due to the positive ions impact on the counter cathode. Results for counters working in different conditions are given. It describes the system to limit the discharge which induces the increase of the life working of a counter, the decrease of its dead time and the reduction of the number of spurious pulses. In a second part, it describes the system to study the time correlation between different particles of the cosmic ray. An experiment concerning the presence of delayed particles in cosmic showers has permitted to specify the superior limit of this phenomena which is directly connected to the presence of heavy nuclear particles in the cosmic shower. (M.P.)

  18. Characteristics and fabrication of Geiger-Mueller counters with thin walls made of treated magnesium - Note about the use of araldite; Caracteristiques et fabrication des compteurs Geiger-Muller a paroi mince en magnesium traite - Note sur l'utilisation de l'araldite

    Energy Technology Data Exchange (ETDEWEB)

    Charbonnel, A

    1949-03-01

    This report describes, first, the advantage of magnesium for the manufacturing of Geiger-Mueller counters: suitable for machining and polishing, but strong reactivity with the counter atmosphere in the case of magnesium-rich alloys. Thus, the inside wall of the counter (cylinder of 20 mm diameter and 6 cm length) requires a non-reactive protective coating with excellent sealing properties. The synthetic resin 'araldite' fulfills all these conditions. The second part of the report describes the different steps of the fabrication of magnesium wall counters: lathe work, machining down and chemical polishing of hulls, assembly, tight sealing, pumping, filling-up and control tests. The average service life of these counters is of about 4 months. A note about the use and properties (hardening, mechanical properties, resistance..) of araldite is given in appendix. (J.S.)

  19. Deriving Case, Agreement and Voice Phenomena in Syntax

    Science.gov (United States)

    Sigurdsson, Einar Freyr

    2017-01-01

    This dissertation places case, agreement and Voice phenomena in syntax. It argues that the derivation is driven by so-called derivational features, that is, structure-building features (Merge) and probe features (Agree) (Heck and Muller 2007 and Muller 2010; see also Chomsky 2000, 2001). Both types are essential in deriving case and agreement in…

  20. 233 - 238 Musa Kifi

    African Journals Online (AJOL)

    User

    2015-12-02

    Dec 2, 2015 ... Dry pods of Piliostigma reticulatum were obtained from. Damfamin –Tofa ... stable flame gas cooker for the respective treatment periods that has to do with ..... composition of Horse Eye bean (Mucuna urens) Asian Journal of ...

  1. Ekuadzi et al. (2

    African Journals Online (AJOL)

    PUBLICATIONS1

    activity of older antibiotics to which the microbes have developed resistance very necessary. The aim of the present study is to investigate the antimicrobial and modulation effects of the 70% ethanol extracts of Lannea schimperi, Commelina nudiflora and Piliostigma reticulatum against susceptible strains of microorganisms.

  2. Good Crab, Bad Crab

    Science.gov (United States)

    Are crabs friends or foes of marsh grass, benefit or detriment to the salt marsh system? We examined Uca pugilator (sand fiddler) and Sesarma reticulatum (purple marsh crab) with Spartina patens (salt marsh hay) at two elevations (10 cm below MHW and 10 cm above MHW) in mesocosms...

  3. 115 - 122_Haruna and Bichi

    African Journals Online (AJOL)

    USER

    2015-06-01

    Jun 1, 2015 ... reticulatum seed were investigated using Association of Officials Analytical Chemists (AOAC,. 1990). ... terms of moderate crude protein (CP) and nitrogen free extract and also had the highest ash content ...... Review of Food Science and Nutrition 34: 31. – 67. ... Development and Coordination Programmes.

  4. Field experiments using the rhabditid nematode Phasmarhabditis hermaphrodita or salt as control measures against slugs in green asparagus

    NARCIS (Netherlands)

    Ester, A.; Rozen, van K.; Molendijk, L.P.G.

    2003-01-01

    Green asparagus (Asparagus officinalis L.) crops are frequently damaged by the grey field slug (Deroceras reticulatum). Most damage occurs in the soil, although some asparagus spears are attacked above ground. In the Netherlands damage occurs especially during the first 5 weeks of harvesting, from

  5. The furrows of Rhinolophidae revisited

    OpenAIRE

    Vanderelst, Dieter; Jonas, Reijniers; Herbert, Peremans

    2012-01-01

    Rhinolophidae, a family of echolocating bats, feature very baroque noseleaves that are assumed to shape their emission beam. Zhuang & Muller (Zhuang & Muller 2006 Phys. Rev. Lett. 97, 218701 (doi:10.1103/PhysRevLett.97.218701); Zhuang & Muller 2007 Phys. Rev. E Stat. Nonlin. Soft Matter Phys. 76(Pt. 1), 051902 (doi:10.1103/PhysRevE.76.051902)) have proposed, based on finite element simulations, that the furrows present in the noseleaves of these bats act as resonance cavities. Using Rhinoloph...

  6. Espécie invasora em unidade de conservação: Achatina fulica (Bowdich, 1822 no Parque Estadual Carlos Botelho, Sete Barras, SP, Brasil (Nota Científica. Invasive species in conservation unit: Achatina fulica (Bowdich, 1822 in Carlos Botelho State Park, Sete Barras, SP, Brazil (Scientific Note.

    Directory of Open Access Journals (Sweden)

    Marilda Rapp de ESTON

    2006-12-01

    Full Text Available O caramujo-gigante-africano, Achatinafulica (Mollusca-Achatinidae, considerado umadas cem piores espécies invasoras do mundo,causando sérios danos ambientais, é registrado pelaprimeira vez para o Parque Estadual CarlosBotelho, município de Sete Barras, Estado de SãoPaulo, Brasil.The Giant African Snail, Achatina fulica(Mollusca-Achatinidae, considered as one of ahundred worst world’s invasive species, causingserious environmental damages, is registered forthe first time for Carlos Botelho State Park, countyof Sete Barras, state of São Paulo, Brazil.

  7. Book review: Musical echoes: South African women thinking in jazz ...

    African Journals Online (AJOL)

    Abstract. Title: Musical echoes: South African women thinking in jazz. Author: Muller, Carol and Sathima, Bea Benjamin. Publisher: Duke University Press. Publication year: 2011. ISBN 978-0-8223-4914-3 ...

  8. 2-2-2-2- عمل آوری پيت خام نيشکر با دما و فشار پايين

    African Journals Online (AJOL)

    morteza

    The effectiveness of different treatment methods to improve the nutritional value of the sugarcane by- ... sugar and paper industries (Muller, 1978). .... The cumulative in vitro gas production data were fitted to the exponential equation GP = B (1 ...

  9. Robotic surgery

    Science.gov (United States)

    ... with this type of surgery give it some advantages over standard endoscopic techniques. The surgeon can make ... Elsevier Saunders; 2015:chap 87. Muller CL, Fried GM. Emerging technology in surgery: Informatics, electronics, robotics. In: ...

  10. Indian Academy of Sciences Conference Series | Indian Academy of ...

    Indian Academy of Sciences (India)

    dynamical approach to the analysis and prediction of atmospheric radon 222Rn concentration using the beta particle activity data of radon monitors (with a pair of Geiger–Muller counters). The approach presented consistently includes a number ...

  11. Oxidative stress and the effect of riboflavin supplementation in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-03-06

    Mar 6, 2009 ... erythrocytes. The results show that there is oxidative stress in malaria infection and that chloroquine ... virulent causing malaria to be life threatening (Kirk, 2001;. Mahajan et al. ..... lifecycle (Muller et al., 2004). However, the ...

  12. Disease: H00480 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available Baynam G, Gillessen-Kaesbach G, Muller U, Steinberger D, Budny B, Badura-Stronka M, Latos-Bielenska A, Ousager LB, Wieacker P, Rodrig...uez Criado G, Bondeson ML, Anneren G, Dufke A, Cohen M,

  13. Two new species of suctorians, Acineta satyanandani sp. nov. and Paracineta karunakarani sp. nov. epizoic on ostracods

    Digital Repository Service at National Institute of Oceanography (India)

    Santhakumari, V.

    Two, species of protozoic suctorians, Acineta satyanandani sp. nov. and Paracineta karunakarani sp. nov., are described. These were found attached on the body of the marine ostracod, Cypridina dentata (Muller), collected from the shelf and slope...

  14. International Journal of Health Research

    African Journals Online (AJOL)

    Erah

    disciplines (including medicine, pharmacy, nursing, biotechnology, cell and ... The journal welcomes original research papers, reviews and case reports on current ..... Asian J. Pharm. 2008; 2:73-76. 5. Rasenack N, Muller BW. Dissolution rate.

  15. Disease: H00630 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available AUTHORS ... Meier FM, Frerix M, Hermann W, Muller-Ladner U ... TITLE ... Current immunotherapy in rheumatoid arthritis. ... JOURNAL ... Immunotherapy 5:955-74 (2013) DOI:10.2217/imt.13.94 ...

  16. Researching the Nokia Mobile Mathematics Service in South Africa

    African Journals Online (AJOL)

    2012), in large scale systemic evaluations of the South African educational landscape (Taylor, Draper, Muller &. Sithole .... technical problems, including lack of network cov- erage, lack ... fee and the data costs (of traffic to and from the service) ...

  17. An Overview of the Asynchronous Digital Systems – Part 3

    Directory of Open Access Journals (Sweden)

    Mihai Timis

    2008-01-01

    Full Text Available Implementation methods for the digital asynchronous systems use different predefined models like self timed circuits, speed independent circuits, delay insensitive circuits, handshake protocol implementation in asynchronous systems,C Muller circuits.

  18. An Overview of the Asynchronous Digital Systems – Part 2

    Directory of Open Access Journals (Sweden)

    Mihai Timis

    2008-01-01

    Full Text Available Implementation methods for the digital asynchronous systems use different predefined models like self timed circuits, speed independent circuits, delay insensitive circuits, handshake protocol implementation in asynchronous systems,C Muller circuits.

  19. 19 February 2015 - Professor Holger Hanselka President Karlsruhe Institute of Technology Federal Republic of Germany

    CERN Multimedia

    Gadmer, Jean-Claude

    2015-01-01

    visiting the CMS cavern with CMS Collaboration Deputy Spokesperson K. Borras and CMS Collaboration, Team Leader, Karlsruhe Institut fur Technologie T. Muller and signing the Guest book with CERN Director-General R. Heuer. C. Schaefer present throughout.

  20. Carmi syndrome associated with gastric perforation

    African Journals Online (AJOL)

    a case of Carmi syndrome in a neonate who presented with an uncommon ... Departments of aPediatric Surgery and bGeneral Surgery, Fr Muller Medical. College ... Emergency laparotomy indicated a large ... evidence of peritonitis. Pyloric ...

  1. An FMM-FFT Accelerated SIE Simulator for Analyzing EM Wave Propagation in Mine Environments Loaded with Conductors

    KAUST Repository

    Yucel, Abdulkadir C.; Sheng, Weitian; Zhou, Chenming; Liu, Yang Z.; Bagci, Hakan; Michielssen, Eric

    2018-01-01

    A fast and memory efficient 3D full wave simulator for analyzing electromagnetic (EM) wave propagation in electrically large and realistic mine tunnels/galleries loaded with conductors is proposed. The simulator relies on Muller and combined field

  2. African Journal of Marine Science - Vol 24 (2002)

    African Journals Online (AJOL)

    Age and growth of the spinner shark Carcharhinus brevipinna (Muller and Henle, .... Life history of white stumpnose Rhabdosargus globiceps (Pisces: Sparidae) off South ... Adaptability of great cormorants Phalacrocorax carbo in a coastal ...

  3. 2083-IJBCS-Article-Mariema BA

    African Journals Online (AJOL)

    hp

    productivité et assurer leur exploitation durable. L'objectif de la présente étude est d'évaluer l'influence des bois raméaux fragmentés (BRF) de G. senegalensis et de P. reticulatum sur la productivité du mil, Pennisetum glaucum (L.) en station. Un dispositif expérimental a été mis en place avec dix traitements composés de ...

  4. Ultrasound pretreatment of filamentous algal biomass for enhanced biogas production.

    Science.gov (United States)

    Lee, Kwanyong; Chantrasakdakul, Phrompol; Kim, Daegi; Kong, Mingeun; Park, Ki Young

    2014-06-01

    The filamentous alga Hydrodictyon reticulatum harvested from a bench-scale wastewater treatment pond was used to evaluate biogas production after ultrasound pretreatment. The effects of ultrasound pretreatment at a range of 10-5000 J/mL were tested with harvested H. reticulatum. Cell disruption by ultrasound was successful and showed a higher degree of disintegration at a higher applied energy. The range of 10-5000 J/mL ultrasound was able to disintegrated H. reticulatum and the soluble COD was increased from 250 mg/L to 1000 mg/L at 2500 J/mL. The disintegrated algal biomass was digested for biogas production in batch experiments. Both cumulative gas generation and volatile solids reduction data were obtained during the digestion. Cell disintegration due to ultrasound pretreatment increased the specific biogas production and degradation rates. Using the ultrasound approach, the specific methane production at a dose of 40 J/mL increased up to 384 mL/g-VS fed that was 2.3 times higher than the untreated sample. For disintegrated samples, the volatile solids reduction was greater with increased energy input, and the degradation increased slightly to 67% at a dose of 50 J/mL. The results also indicate that disintegration of the algal cells is the essential step for efficient anaerobic digestion of algal biomass. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Combined Effects of Ocean Acidification and Light or Nitrogen Availabilities on 13C Fractionation in Marine Dinoflagellates.

    Directory of Open Access Journals (Sweden)

    Mirja Hoins

    Full Text Available Along with increasing oceanic CO2 concentrations, enhanced stratification constrains phytoplankton to shallower upper mixed layers with altered light regimes and nutrient concentrations. Here, we investigate the effects of elevated pCO2 in combination with light or nitrogen-limitation on 13C fractionation (εp in four dinoflagellate species. We cultured Gonyaulax spinifera and Protoceratium reticulatum in dilute batches under low-light ('LL' and high-light ('HL' conditions, and grew Alexandrium fundyense and Scrippsiella trochoidea in nitrogen-limited continuous cultures ('LN' and nitrogen-replete batches ('HN'. The observed CO2-dependency of εp remained unaffected by the availability of light for both G. spinifera and P. reticulatum, though at HL εp was consistently lower by about 2.7‰ over the tested CO2 range for P. reticulatum. This may reflect increased uptake of (13C-enriched bicarbonate fueled by increased ATP production under HL conditions. The observed CO2-dependency of εp disappeared under LN conditions in both A. fundyense and S. trochoidea. The generally higher εp under LN may be associated with lower organic carbon production rates and/or higher ATP:NADPH ratios. CO2-dependent εp under non-limiting conditions has been observed in several dinoflagellate species, showing potential for a new CO2-proxy. Our results however demonstrate that light- and nitrogen-limitation also affect εp, thereby illustrating the need to carefully consider prevailing environmental conditions.

  6. Combined Effects of Ocean Acidification and Light or Nitrogen Availabilities on 13C Fractionation in Marine Dinoflagellates.

    Science.gov (United States)

    Hoins, Mirja; Eberlein, Tim; Groβmann, Christian H; Brandenburg, Karen; Reichart, Gert-Jan; Rost, Björn; Sluijs, Appy; Van de Waal, Dedmer B

    2016-01-01

    Along with increasing oceanic CO2 concentrations, enhanced stratification constrains phytoplankton to shallower upper mixed layers with altered light regimes and nutrient concentrations. Here, we investigate the effects of elevated pCO2 in combination with light or nitrogen-limitation on 13C fractionation (εp) in four dinoflagellate species. We cultured Gonyaulax spinifera and Protoceratium reticulatum in dilute batches under low-light ('LL') and high-light ('HL') conditions, and grew Alexandrium fundyense and Scrippsiella trochoidea in nitrogen-limited continuous cultures ('LN') and nitrogen-replete batches ('HN'). The observed CO2-dependency of εp remained unaffected by the availability of light for both G. spinifera and P. reticulatum, though at HL εp was consistently lower by about 2.7‰ over the tested CO2 range for P. reticulatum. This may reflect increased uptake of (13C-enriched) bicarbonate fueled by increased ATP production under HL conditions. The observed CO2-dependency of εp disappeared under LN conditions in both A. fundyense and S. trochoidea. The generally higher εp under LN may be associated with lower organic carbon production rates and/or higher ATP:NADPH ratios. CO2-dependent εp under non-limiting conditions has been observed in several dinoflagellate species, showing potential for a new CO2-proxy. Our results however demonstrate that light- and nitrogen-limitation also affect εp, thereby illustrating the need to carefully consider prevailing environmental conditions.

  7. Determination of shell deposition rates of Arctica islandica from the New York Bight using natural 228Ra and 228Th and bomb-produced 14C

    International Nuclear Information System (INIS)

    Turekian, K.K.; Cochran, J.K.; Nozaki, Y.; Thompson, I.; Jones, D.S.

    1982-01-01

    Shell deposition rates of specimens of Arctica islandica (Mollusca: Bivalvia) from the New York Bight were determined using natural 228 Ra and 228 Th and bomb 14 C. The specimens from deep (>55 m) offshore waters show annual growth banding. A shell obtained from the inner bight at <30-m depth seems to be younger than indicated by band counting

  8. The role of host specificity in explaining the invasion success of the freshwater mussel Anodonta woodiana in Europe

    Czech Academy of Sciences Publication Activity Database

    Douda, K.; Vrtílek, Milan; Slavík, O.; Reichard, Martin

    2012-01-01

    Roč. 14, č. 1 (2012), s. 127-137 ISSN 1387-3547 R&D Projects: GA AV ČR KJB600930802 Institutional research plan: CEZ:AV0Z60930519 Keywords : aquatic habitat * Bivalvia * host-parasite relationship * host specificity * Mollusca Subject RIV: EG - Zoology Impact factor: 2.509, year: 2012

  9. The oyster genome reveals stress adaptation and complexity of shell formation

    DEFF Research Database (Denmark)

    Zhang, Guofan; Fang, Xiaodong; Guo, Ximing

    2012-01-01

    The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress re...

  10. Ecology of benthic production in the coastal zone of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Harkantra, S.N.; Parulekar, A.H.

    was comprised of Polychaeta (58.5%), Mollusca (18.1%), Crustacea (9.1%), Echinodermata (7.1%) and other minor taxa (7.3%) Population count and biomass varied from 25 to 7823 m-2 (X- = 1256 m-2) and 0.2 to 2251.25 g m-2 (X- = 67.07 g m-2) respectively The higher...

  11. Applicability of the black slug Arion ater for monitoring exposure to polycyclic aromatic hydrocarbons and their subsequent bioactivation into DNA binding metabolites

    NARCIS (Netherlands)

    Hamers, T.; Kalis, E.J.J.; Berg, van den J.H.J.; Maas, L.M.; Schooten, van F.J.; Murk, A.J.

    2004-01-01

    The applicability of terrestrial black slugs Arion ater (Mollusca, Gastropoda) was studied for biomonitoring environmental exposure to polycyclic aromatic hydrocarbons (PAHs). In laboratory experiments, slugs were orally exposed to benzo[a]pyrene (BaP) for a short term (3 days) or a long term (119

  12. Malakostratigrafie vchodového valu Medvědí jeskyně ve Slovenském ráji

    Czech Academy of Sciences Publication Activity Database

    Ložek, Vojen

    2012-01-01

    Roč. 2011, podzim (2012), s. 219-222 ISSN 0514-8057 Institutional research plan: CEZ:AV0Z30130516 Keywords : Slovenský raj * Medvedia Cave * entrance rampart * Holocene * Mollusca * foam sinter Subject RIV: DB - Geology ; Mineralogy http://www.geology.cz/zpravy/obsah/2011/zpravy_2011-49.pdf

  13. Water SA - Vol 43, No 2 (2017)

    African Journals Online (AJOL)

    Sensitivity to selected contaminants in a biological early warning system using Anodonta woodiana (Mollusca) · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Luisa Giari, Fabio Vincenzi, Elisa Anna Fano, Ivano Graldi, Fernando Gelli, Giuseppe Castaldelli, 200-208.

  14. Stratigrafie a malakofauna holocenní výplně jeskyně Pod valem (Zádielská tiesňava, NP Slovenský kras)

    Czech Academy of Sciences Publication Activity Database

    Ložek, Vojen

    2011-01-01

    Roč. 2010, - (2011), s. 62-65 ISSN 0514-8057 Institutional research plan: CEZ:AV0Z30130516 Keywords : Slovak Karst * cave fill * extreme habitat * Holocene * Mollusca * Zebrina detrita Subject RIV: DB - Geology ; Mineralogy http://www.geology.cz/zpravy/obsah/2010/zpravy-2010-14.pdf

  15. Chronostratigrafická revize a paleoklimatický význam osypu pod stěnou Martinky (CHKO) v Biosférické rezervaci Pálava

    Czech Academy of Sciences Publication Activity Database

    Ložek, Vojen

    2011-01-01

    Roč. 2010, - (2011), s. 66-69 ISSN 0514-8057 Institutional research plan: CEZ:AV0Z30130516 Keywords : Pálava Mils * talus deposit * Mollusca * Climatic Optimum * erosion Subject RIV: DB - Geology ; Mineralogy http://www.geology.cz/zpravy/obsah/2010/zpravy-2010-15.pdf

  16. AN EVALUATION OF THREE CONVENTIONAL HISTOLOGICAL TECHNIQUES FOR STAINING THE CERATA OF CRATENA PILATA

    Science.gov (United States)

    Fixation and staining methods for different types of tissue in the marine nudibranch Cratena pilata were evaluated. Cratena pilata, a marine snail in the Phylum Mollusca, has the ability to take stinging cells, called nematocysts, from ingested animals belonging to another phylum...

  17. Vertigo substriata Jeffreys, faunae neerlandicae nova species, een zoogenaamd glaciaalrelikt

    NARCIS (Netherlands)

    Sunier, A.L.J.

    1926-01-01

    I. HET NEDERLANDSCHE MATERIAAL VAN VERTIGO SUBSTRIATA JEFFR.. Onder het vaak interessante materiaal van Nederlandsche Mollusca, dat den laatsten tijd door de Heeren W. F. van Hell en J. A. Nijkamp, studenten in de biologie te Leiden, aan 's Rijks Museum van Natuurlijke Historie werd afgestaan, trof

  18. Benthos off Cochin, Southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Harkantra, S.N.; Parulekar, A.H.

    Macro-invertebrate benthic fauna off Cochin mainly composed of polychaeta (82.45%), crustacea (7.62%), mollusca (5.92%), sipuncula (2.25%), nemertinea (0.96%) and echinodermata (0.80%). The maximum population density and biomass values were 304 plus...

  19. Food selection preference of different ages and sizes of black tiger ...

    African Journals Online (AJOL)

    Yomi

    2012-03-15

    Mar 15, 2012 ... Key words: Aquaculture, natural food, Penaeus monodon, Malaysia. INTRODUCTION ... Many researchers who reported on the diet of Penaeus species in ..... matter, annelida, mollusca and small fish in estuarine water. .... planktonic and benthic communities to fertilizer and feed application in shrimp ...

  20. Rostrokonchy z devonských sedimentů moravskoslezské pánve

    Czech Academy of Sciences Publication Activity Database

    Weinerová, Hedvika; Weiner, Tomáš; Hladil, Jindřich

    2017-01-01

    Roč. 50, č. 1 (2017), s. 153-157 ISSN 0514-8057 R&D Projects: GA ČR GA14-18183S Institutional support: RVO:67985831 Keywords : Rostroconchia * Mollusca * Devonian * Moravo-Silesian Basin Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology