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Sample records for opisthobranchia gastropoda mollusca

  1. Record of Phyllidiella zeylanica (Mollusca: Gastropoda: Opisthobranchia after 42 years from Gujarat, India

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    M. Matwal

    2011-07-01

    Full Text Available There are few studies available on Opisthobranch fauna of Gujarat coast. Field surveys were carried out along the Mithapur reef under the “Coral reef restoration programme” of Wildlife Trust of India funded by Tata chemicals and supported by Gujarat State Forest Department and Marine National Park authorities. A species of nudibranch Phyllidiella zeylanica (Mollusca: Gastropoda: Opisthobranchia was recorded for Gujarat after 42 years. This species was last reported by Narayanan in 1968 at Pirotan Islands, Gulf of Kutch Gujarat.

  2. Phylogenetic relationships among Opisthobranchia (Mollusca: Gastropoda) based on mitochondrial cox 1, trnV, and rrnL genes.

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    Grande, Cristina; Templado, Josè; Cervera, J Lucas; Zardoya, Rafael

    2004-11-01

    We reconstructed the phylogenetic relationships among 37 species representing seven main lineages within Opisthobranchia (Mollusca: Gastropoda) based on a mitochondrial fragment that included partial cox 1, complete trnV, and partial rrnL genes (about 2500 bp). Phylogenetic analyses confirmed tentatively that all studied main opisthobranch lineages conformed monophyletic groups except Nudibranchia. The sacoglossan Ascobulla was placed as the most basal lineage of opisthobranchs. The basommatophoran pulmonate Siphonaria was recovered within Opisthobranchia between Ascobulla and the remaining opisthobranchs. The latter were divided into two different lineages that await formal description: on one side, Cephalaspidea, Tylodinoidea, and Anaspidea (sharing features in the reproductive, digestive, and circulatory systems) were grouped together and, on the other Architectibranchia and Nudipleura (sharing similarities in the circulatory system) were recovered as sister group taxa. Two well-supported clades were recovered within Nudipleura: Pleuroanthobranchia (new taxon) and Cladobranchia. Pleuroanthobranchia (Pleurobranchoidea plus Anthobranchia) was defined by the presence of blood gland, the presence of calcareous spicules in the integument and the presence of a caecum with an opening directly into the stomach. The new molecular phylogeny provided a robust framework for comparative studies, and prompted a revision of the morphological synapomorphies diagnosing the main clades within opisthobranchs. PMID:15336672

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

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

    2012-06-26

    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

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

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    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.

  5. A comparative ultrastructural investigation of the cephalic sensory organs in Opisthobranchia (Mollusca, Gastropoda).

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    Göbbeler, K; Klussmann-Kolb, A

    2007-12-01

    Cephalic sensory organs (CSOs) are specialised structures in the head region of adult Opisthobranchia involved in perception of different stimuli. The gross morphology of these organs differs considerably among taxa. The current study aims at describing the cellular morphology of the CSOs in order to reveal cellular patterns, especially of sensory epithelia, common for opisthobranchs. Transmission electron microscopy was used to characterise the fine structure of the organs and to compare the CSOs of four different opisthobranch species. The cellular composition of the sensory system is conserved among taxa. The epidermal cells in sensory regions are always columnar and ciliated cells are frequently apparent. The sensory cells are primary receptors arranged in subepidermal cell clusters. They extend dendrites which penetrate the epithelium and reach the surface. Some of the dendrites bear cilia, whereas others only build a small protuberance. Processing of sensory information takes place in the peripheral glomeruli of all species. Moreover, few taxa possess additional peripheral ganglia at the base of their CSOs. The results of the present study might support other investigations indicating that the posterior CSOs are primarily involved in distance chemoreception, whereas the anterior CSOs might be used for contact chemoreception and mechanoreception. PMID:17881026

  6. Opisthobranchia (Mollusca, Gastropoda) - more than just slimy slugs. Shell reduction and its implications on defence and foraging.

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    Wägele, Heike; Klussmann-Kolb, Annette

    2005-02-16

    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. PMID:15715915

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

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    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.

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

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    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 Jeff

  9. Molecular phylogeny of euthyneura (mollusca: gastropoda).

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    Grande, Cristina; Templado, José; Cervera, J Lucas; Zardoya, Rafael

    2004-02-01

    A new phylogenetic hypothesis for Euthyneura is proposed based on the analysis of primary sequence data (mitochondrial cox1, trnV, rrnL, trnL(cun), trnA, trnP, nad6, and nad5 genes) and the phylogenetic utility of two rare genomic changes (the relative position of the mitochondrial trnP gene, and an insertion/deletion event in a conserved region of the mitochondrial Cox1 protein) is addressed. Both sources of phylogenetic information clearly rejected the monophyly of pulmonates, a group of gastropods well supported so far by morphological evidence. The marine basommatophoran pulmonate Siphonaria was placed within opisthobranchs and shared with them the insertion of a Glycine in the Cox 1 protein. The marine systellommatophoran pulmonate Onchidella was recovered at the base of the opisthobranch + Siphonaria clade. Opisthobranchs, Siphonaria, and Onchidella shared the relative position of the mitochondrial trnP gene between the mitochondrial trnA and nad6 genes. The land snails and slugs (stylommatophoran pulmonates) were recovered as an early split in the phylogeny of advanced gastropods. The monophyly of the Euthyneura (Opisthobranchia + Pulmonata) was rejected by the inclusion of the heterostrophan Pyramidella. PMID:14660702

  10. Inventarisatie van de landslakken van de Zeeuwse kust, met de nadruk op de nauwe korfslak Vertigo angustior (Mollusca: Gastropoda).

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    Boesveld, A.

    2006-01-01

    The distribution of the land snails of the province of Zeeland, with special emphasis on Vertigo angustior (Mollusca: Gastropoda) In 2005 the land snail fauna of the coast of the province of Zeeland was mapped. In total 98 soil and litter samples were taken and on 54 localities records were gathered

  11. From sea to land and beyond – New insights into the evolution of euthyneuran Gastropoda (Mollusca

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    Streit Bruno

    2008-02-01

    Full Text Available Abstract Background The Euthyneura are considered to be the most successful and diverse group of Gastropoda. Phylogenetically, they are riven with controversy. Previous morphology-based phylogenetic studies have been greatly hampered by rampant parallelism in morphological characters or by incomplete taxon sampling. Based on sequences of nuclear 18S rRNA and 28S rRNA as well as mitochondrial 16S rRNA and COI DNA from 56 taxa, we reconstructed the phylogeny of Euthyneura utilising Maximum Likelihood and Bayesian inference methods. The evolution of colonization of freshwater and terrestrial habitats by pulmonate Euthyneura, considered crucial in the evolution of this group of Gastropoda, is reconstructed with Bayesian approaches. Results We found several well supported clades within Euthyneura, however, we could not confirm the traditional classification, since Pulmonata are paraphyletic and Opistobranchia are either polyphyletic or paraphyletic with several clades clearly distinguishable. Sacoglossa appear separately from the rest of the Opisthobranchia as sister taxon to basal Pulmonata. Within Pulmonata, Basommatophora are paraphyletic and Hygrophila and Eupulmonata form monophyletic clades. Pyramidelloidea are placed within Euthyneura rendering the Euthyneura paraphyletic. Conclusion Based on the current phylogeny, it can be proposed for the first time that invasion of freshwater by Pulmonata is a unique evolutionary event and has taken place directly from the marine environment via an aquatic pathway. The origin of colonisation of terrestrial habitats is seeded in marginal zones and has probably occurred via estuaries or semi-terrestrial habitats such as mangroves.

  12. The complete mitochondrial genome of the nudibranch Roboastra europaea (Mollusca: Gastropoda) supports the monophyly of opisthobranchs.

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    Grande, Cristina; Templado, José; Cervera, J Lucas; Zardoya, Rafael

    2002-10-01

    The complete nucleotide sequence (14,472 bp) of the mitochondrial genome of the nudibranch Roboastra europaea (Gastropoda: Opisthobranchia) was determined. This highly compact mitochondrial genome is nearly identical in gene organization to that found in opisthobranchs and pulmonates (Euthyneura) but not to that in prosobranchs (a paraphyletic group including the most basal lineages of gastropods). The newly determined mitochondrial genome differs only in the relative position of the trnC gene when compared with the mitochondrial genome of Pupa strigosa, the only opisthobranch mitochondrial genome sequenced so far. Pupa and Roboastra represent the most basal and derived lineages of opisthobranchs, respectively, and their mitochondrial genomes are more similar in sequence when compared with those of pulmonates. All phylogenetic analyses (maximum parsimony, minimum evolution, maximum likelihood, and Bayesian) based on the deduced amino acid sequences of all mitochondrial protein-coding genes supported the monophyly of opisthobranchs. These results are in agreement with the classical view that recognizes Opisthobranchia as a natural group and contradict recent phylogenetic studies of the group based on shorter sequence data sets. The monophyly of opisthobranchs was further confirmed when a fragment of 2,500 nucleotides including the mitochondrial cox1, rrnL, nad6, and nad5 genes was analyzed in several species representing five different orders of opisthobranchs with all common methods of phylogenetic inference. Within opisthobranchs, the polyphyly of cephalaspideans and the monophyly of nudibranchs were recovered. The evolution of mitochondrial tRNA rearrangements was analyzed using the cox1+rrnL+nad6+nad5 gene phylogeny. The relative position of the trnP gene between the trnA and nad6 genes was found to be a synapomorphy of opisthobranchs that supports their monophyly. PMID:12270894

  13. The long way to diversity--phylogeny and evolution of the Heterobranchia (Mollusca: Gastropoda).

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    Dinapoli, Angela; Klussmann-Kolb, Annette

    2010-04-01

    Heterobranchia are one of the most species rich groups within Gastropoda, with poorly resolved phylogenetic relationships especially in basal taxa. In order to resolve phylogenetic relationships within the Heterobranchia, we pursued a molecular systematic approach by sequencing and analysing a variety of genetic markers (including nuclear 28S rDNA+18S rDNA and mitochondrial 16S rDNA+COI sequences). Maximum likelihood as well as Bayesian inference methods were used for phylogenetic reconstruction. Moreover, data quality was estimated for the purpose of proving the plausibility of the novel phylogenetic hypothesis using a variety of statistical tests as well as network analyses. Finally, a case study was conducted in order to estimate divergence ages using a "relaxed" molecular clock approach with fossils as minimum age constraints. All phylogenetic analyses revealed the Heterobranchia as monophyletic. Within the Heterobranchia, several well supported clades could be resolved. However, the traditional classification based on morphological data could not be confirmed due to paraphyletic Euthyneura as well as paraphyletic Pulmonata and polyphyletic Opisthobranchia. The estimation of data quality yielded a high degree of substitution saturation in many of the nucleotide positions while the Relative-Rate-Test revealed the highest evolution rates within the "Lower Heterobranchia". Although the dataset shows much conflict, many of the proposed hypotheses are supported by splits of the network analysis. The molecular clock approach was able to confirm some evolutionary hypotheses based on fossils such as the late occurrence of Pulmonata and Stylommatophora, respectively, during the Mesozoic. However, large 95% highest posterior density (HPD) intervals at some of the nodes made a precise dating of these nodes difficult. This molecular phylogenetic investigation provides the most comprehensive molecular study of relationships within the Heterobranchia to date. Due to the

  14. Two new species of Naticidae (Mollusca ,Gastropoda) from the coast of China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Suping

    2008-01-01

    Two new species of Naticidae (Mollusca,Gastropoda) collected from the coast of China are described:Cryptonaitca huanghaien- sis sp.nov.and Sinum vittatum sp.nov.The morphological characteristics between the new species were described and the relat- ed information was provided.The similarities and differences between the new species and related species were also compared and discussed.The new species Cryptonaitca huanghaiensis differed from Cryptonaitca hirasei and Cryptonaitca andoi in outer shape, operculum and radula.The new species Sinum vittatum is similar to Sinum japonicum (Lischke,1869),but the shell of the for- mer is flat-elliptical in shape,spire very small,slightly convex.While the latter is flat-globular in shape,apex light brown in col- or,without a brown band on the body whorl.The comparison results revealed that Cryptonaitca huanghaiensis and Sinum vittatum were two new species from the coast of China.Specimens studied were obtained from collections in the Marine Biological Museum, Chinese Academy of Sciences.

  15. The complete mitochondrial genome of Galba pervia (Gastropoda: Mollusca, an intermediate host snail of Fasciola spp.

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    Guo-Hua Liu

    Full Text Available Complete mitochondrial (mt genomes and the gene rearrangements are increasingly used as molecular markers for investigating phylogenetic relationships. Contributing to the complete mt genomes of Gastropoda, especially Pulmonata, we determined the mt genome of the freshwater snail Galba pervia, which is an important intermediate host for Fasciola spp. in China. The complete mt genome of G. pervia is 13,768 bp in length. Its genome is circular, and consists of 37 genes, including 13 genes for proteins, 2 genes for rRNA, 22 genes for tRNA. The mt gene order of G. pervia showed novel arrangement (tRNA-His, tRNA-Gly and tRNA-Tyr change positions and directions when compared with mt genomes of Pulmonata species sequenced to date, indicating divergence among different species within the Pulmonata. A total of 3655 amino acids were deduced to encode 13 protein genes. The most frequently used amino acid is Leu (15.05%, followed by Phe (11.24%, Ser (10.76% and IIe (8.346%. Phylogenetic analyses using the concatenated amino acid sequences of the 13 protein-coding genes, with three different computational algorithms (maximum parsimony, maximum likelihood and bayesian analysis, all revealed that the families Lymnaeidae and Planorbidae are closely related two snail families, consistent with previous classifications based on morphological and molecular studies. The complete mt genome sequence of G. pervia showed a novel gene arrangement and it represents the first sequenced high quality mt genome of the family Lymnaeidae. These novel mtDNA data provide additional genetic markers for studying the epidemiology, population genetics and phylogeographics of freshwater snails, as well as for understanding interplay between the intermediate snail hosts and the intra-mollusca stages of Fasciola spp..

  16. Initial results on the molecular phylogeny of the Nudibranchia (Gastropoda, Opisthobranchia) based on 18S rDNA data.

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    Wollscheid, E; Wägele, H

    1999-11-01

    This study investigated nudibranch phylogeny on the basis of 18S rDNA sequence data. 18S rDNA sequence data of 19 taxa representing the major living orders and families of the Nudibranchia were analyzed. Representatives of the Cephalaspidea, Anaspidea, Gymnomorpha, Prosobranchia, and Pulmonata were also sequenced and used as outgroups. An additional 28 gastropod sequences taken from GenBank were also included in our analyses. Phylogenetic analyses of these more than 50 gastropod taxa provide strong evidence for support of the monophyly of the Nudibranchia. The monophyly of the Doridoidea, Cladobranchia, and Aeolidoidea within the Nudibranchia are also strongly supported. Phylogenetic utility and information content of the 18S rDNA sequences for Nudibranchia, and Opisthobranchia in general, are examined using the program SplitsTree as well as phylogenetic reconstructions using distance and parsimony approaches. 0Results based on these molecular data are compared with hypotheses about nudibranch phylogeny inferred from morphological data. PMID:10603252

  17. The Marine Mollusca of Suriname (Dutch Guiana) Holocene and recent Part III. Gastropoda and Cephalopoda

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    Regteren Altena, van C.O.

    1975-01-01

    CONTENTS 1. Introduction, systematic survey and page references....... 3 2. Gastropoda and Cephalopoda............. 8 3. List of corrections of and additions to Part II......... 89 4. References.................. 92 5. Plates ................... 100 1. INTRODUCTION, SYSTEMATIC SURVEY AND PAGE REFERE

  18. Land snails (Mollusca: Gastropoda) of India: status, threats and conservation strategies

    OpenAIRE

    Sen, S.; Ravikanth, G; N.A. Aravind

    2012-01-01

    Land snails form an important component in the forest ecosystem. In terms of number of species, the phylum Mollusca, to which land snails belong, is the largest phylum after Arthropoda. Mollusca provide unique ecosystem services including recycling of nutrients and they provide a prey base for small mammals, birds, snakes and other reptiles. However, land snails have the largest number of documented extinctions, compared to any other taxa. Till date 1,129 species of land snails are recorde...

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

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

    2008-07-01

    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 transmission electron microscopy. Within the scope of the present study we investigated the myogenesis of premetamorphic, metamorphic, and juvenile developmental stages of the anaspidean opisthobranch Aplysia californica using fluorescence F-actin-labeling in conjunction with modern confocal laser scanning microscopy. We categorized muscles with respect to their differentiation and degeneration and found three true larval muscles that differentiate during the embryonic and veliger phase and degenerate during or slightly after metamorphosis. These are the larval retractor, the accessory larval retractor, and the metapodial retractor muscle. While the pedal retractor muscle, some transversal mantle fibers and major portions of the cephalopedal musculature are continued and elaborated during juvenile and adult life, the buccal musculature and the anterior retractor muscle constitute juvenile/adult muscles which differentiate during or after metamorphosis. The metapodial retractor muscle has never been reported for any other gastropod taxon. Our findings indicate that the late veliger larva of A. californica shares some common traits with veligers of other gastropods, such as a larval retractor muscle. However, the postmetamorphic stages exhibit only few congruencies with other gastropod taxa investigated to date, which is probably due to common larval but different adult life styles within gastropods. Accordingly, this study provides further evidence for morphological plasticity in gastropod myogenesis and stresses the importance of ontogenetic approaches to understand adult conditions and life history patterns. PMID:18157859

  20. 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...... the importance of ontogenetic approaches to understand adult conditions and life history patterns....

  1. Land snails (Mollusca: Gastropoda of India: status, threats and conservation strategies

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    S. Sen

    2012-09-01

    Full Text Available Land snails form an important component in the forest ecosystem. In terms of number of species, the phylum Mollusca, to which land snails belong, is the largest phylum after Arthropoda. Mollusca provide unique ecosystem services including recycling of nutrients and they provide a prey base for small mammals, birds, snakes and other reptiles. However, land snails have the largest number of documented extinctions, compared to any other taxa. Till date 1,129 species of land snails are recorded from Indian territory. But only basic information is known about their taxonomy and little is known of their population biology, ecology and their conservation status. In this paper, we briefly review status, threats and conservation strategies of land snails of India.

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

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    Klussmann-Kolb Annette

    2010-01-01

    Full Text Available 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 data on opisthobranch gastropods we investigated the neuromuscular development in the nudibranch Aeolidiella stephanieae Valdéz, 2005 using immunocytochemistry as well as F-actin labelling in conjunction with confocal laser scanning microscopy (cLSM. Results The ontogenetic development of Aeolidiella stephanieae can be subdivided into 8 stages, each recognisable by characteristic morphological and behavioural features as well as specific characters of the nervous system and the muscular system, respectively. The larval nervous system of A. stephanieae includes an apical organ, developing central ganglia, and peripheral neurons associated with the velum, foot and posterior, visceral part of the larva. The first serotonergic and FMRFamidergic neural structures appear in the apical organ that exhibits an array of three sensory, flask-shaped and two non-sensory, round neurons, which altogether disappear prior to metamorphosis. The postmetamorphic central nervous system (CNS becomes concentrated, and the rhinophoral ganglia develop together with the anlage of the future rhinophores whereas oral tentacle ganglia are not found. The myogenesis in A. stephanieae begins with the larval retractor muscle followed by the accessory larval retractor muscle, the velar or prototroch muscles and the pedal retractors that all together degenerate during metamorphosis, and the adult muscle complex forms de novo. Conclusions Aeolidiella stephanieae comprises features of the larval and postmetamorphic nervous as well as muscular system that represent the ground plan of the Mollusca or even the Trochozoa (e. g. presence of the prototrochal or velar muscle ring. On the one hand

  3. Exotic molluscs (Mollusca, Gastropoda et Bivalvia in Santa Catarina State, Southern Brazil region: check list and regional spatial distribution

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    A. Ignacio Agudo-Padrón

    2011-06-01

    Full Text Available A total of twenty-one exotic mollusc taxa were assessed for Santa Catarina State (SC, fifteen Gastropoda andsix Bivalvia (twelve terrestrial, five limnic/freshwater - three gastropods and two bivalves, and four marinebivalves. Of these, fourteen are confirmed as invasive species (nine terrestrial, three limnic/freshwater, andtwo marine.

  4. Original molluscan radula: comparisons among Aplacophora, Polyplacophora, Gastropoda, and the Cambrian fossil Wiwaxia corrugata.

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    Scheltema, Amélie H; Kerth, Klaus; Kuzirian, Alan M

    2003-08-01

    As the original molluscan radula is not known from direct observation, we consider what the form of the original radula may have been from evidence provided by neomenioid Aplacophora (Solenogastres), Gastropoda, Polyplacophora, and the Cambrian fossil Wiwaxia corrugata (Matthews). Conclusions are based on direct observation of radula morphology and its accessory structures (salivary gland ducts, radular sac, anteroventral radular pocket) in 25 species and 16 genera of Aplacophora; radula morphogenesis in Aplacophora; earliest tooth formation in Gastropoda (14 species among Prosobranchia, Opisthobranchia, and Pulmonata); earliest tooth formation in four species of Polyplacophora; and the morphology of the feeding apparatus in W. corrugata. The existence of a true radula membrane and of membranoblasts and odontoblasts in neomenioids indicates that morphogenesis of the aplacophoran radula is homologous to that in other radulate Mollusca. We conclude from p redness of salivary gland ducts, a divided radular sac, and a pair of anteroventral pockets that the plesiomorphic state in neomenioids is bipartite, formed of denticulate bars that are distichous (two teeth per row) on a partially divided or fused radula membrane with the largest denticles lateral, as occurs in the genus Helicoradomenia. The tooth morphology in Helicoradomenia is similar to the feeding apparatus in W. corrugata. We show that distichy also occurs during early development in several species of gastropods and polyplacophorans. Through the rejection of the null hypothesis that the earliest radula was unipartite and had no radula membrane, we conclude that the original molluscan radula was similar to the radula found in Helicoradomena species. PMID:12833382

  5. Incorporated nematocysts in Aeolidiella stephanieae (Gastropoda, Opisthobranchia, Aeolidoidea) mature by acidification shown by the pH sensitive fluorescing alkaloid Ageladine A.

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    Obermann, Dana; Bickmeyer, Ulf; Wägele, Heike

    2012-11-01

    The sequestration of nematocysts (a special group of cnidocysts) from cnidarian prey with subsequent use in defence is described for few metazoan phyla. Members of the taxon Aeolidoidea (Nudibranchia, Gastropoda) are well-known for this. Questions regarding the reasons some nematocysts do not discharge when the gastropod feeds and how these same nematocysts can be transported along the digestive tract into specialized morphological structures called cnidosacs, remain unanswered. Within the cnidosac, nematocysts are incorporated in cells and finally be used for defence against predators. The most plausible explanation for this phenomenon suggests there are immature and therefore non-functional nematocysts in the food. A recent study by Berking and Herrmann (2005) on cnidarians suggested that the nematocysts mature by acidification via proton transfer into the nematocyst capsule. According to this hypothesis only immature nematocysts are transported into the cnidosac where they are then made functional through an accumulation of protons. In this study we present a fluorescence staining method that tests the hypothesis by Berking and Herrmann (2005) and detects changes in the pH values of incorporated nematocysts, interpreted as changes in maturation stages. This marker, the fluorescent dye Ageladine A, stains nematocyst capsules according to their pH values. With Ageladine A we were able to show that kleptocnides indeed change their pH value after incorporation into the aeolidoidean cnidosac. PMID:22910369

  6. First record of Okenia pellucid Burn, 1967 (Mollusca: Nudibranchia from India

    Directory of Open Access Journals (Sweden)

    V. Bhave

    2012-11-01

    Full Text Available There are very few records of opisthobranchs in comparison to the vastness of Indian coasts. The published records are very patchy and limited to a few areas such as Gulf of Kutch, Gulf of Mannar, Lakshadweep and Andaman Nicobar Islands. The present paper records Okenia pellucida Burn, 1967 (Mollusca: Opisthobranchia for the first time from India on the south-western coast of Maharashtra. This nudibranch is known to be associated with fouling bryozoans Zoobotryon verticillatum.

  7. Acid phosphatase localization in neurons of Bulla gouldiana (Gastropoda: Opisthobranchia.

    Science.gov (United States)

    Robles, L J; Fisher, S K

    1975-01-01

    The organization of the ganglia and the ultrastructure of the neurons of Bulla gouldiana are similar to those described for other molluscs. Acid phosphatase positive reactions were found in the large pigmented granules, small dense bodies, multivesicular bodies, and Golgi lamellae and associated vesicles. The small dense bodies and multivesicular bodies may be stages in the formation of the larger pigmented granules which are interpreted as lysosomes. Comparison is made between the pigmented granules in Bulla and the lipofuscin bodies of vertebrate neurons. The possible involvement of these pigmented granules in the hyperpolarization of Bulla and Aplysia neurons to light is discussed. PMID:1122539

  8. Holoplanktonic Mollusca: development in the Mediterranean Basin during the last 30 million years and their future

    NARCIS (Netherlands)

    A.W. Janssen; K.T.C.A. Peijnenburg

    2014-01-01

    A short introduction is given to the systematics and morphology of pelagic Gastropoda (Mollusca: Heteropoda and Pteropoda), also explaining some details of the animals’ particular way of life. The fossil record of these invertebrates is discussed briefly, followed by an overview of existing literatu

  9. [Evolutionary regularities of somatic polyploidy expansion in salivary glands of gastropod mollusks. V. Subclasses Opisthobranchia and Pulmonata].

    Science.gov (United States)

    Anisimov, A P; Ziumchenko, N E

    2012-01-01

    Salivary glands of 25 species of euthyneural gastropod mollusks (Opisthobranchia and Pulmonata) have been investigated by means of histochemical methods and DNA cytophotometry in nuclei of cells. The cells of three basic types are distinguished in glandular epithelim: granular cells (with glicoproteid granular inclusions), mucocytes-I (with sulfatic acid mucopolysaccharides) and mucocytes-II (with neutral and acid nonsulfatic polysaccharides and proteins) and so the epithelial ciliated cells and cells of the ducts. It was shown that glandular cells of salivary glands of all discovered mollusks' species are polyploid in different degree. The highest ploidy level estimated by means of DNA content in most of species is 64-128c. The giant polyploidy, attained to 4096c, is discovered in cells of salivary glands of Tritonia diomedea. The functional conditionality connected with features of feeding of different mollusk species and phylogenetic tendencies of expansion of somatic polyploidy in class Gastropoda are discussed. In comparison with allogenic, facultative and small polyploidy manifestation in Prosobranchia the obligatory polyploidization of high degree revealed in cells of salivary glands of Opisthobranchia and Pulmonata is consider to be the original cytological arogenesis. The probable causes of such differences are conneted with euthyneural type of organization of central nervous system and giant polyploidy of neurons in Opisthobranchia and Pulmonata mollusks. The causes, mechanisms and significance of such correlations are unclear for the present. PMID:22590930

  10. Mollusca contagiosa

    OpenAIRE

    Husar, Karmela; Skerlev, Mihael; Husar, Darko

    2009-01-01

    Mollusca contagiosa (MC) definiramo kao čestu virusnu infekciju kože uzrokovanu Molluscipox virusom (MCV) koja se viđa u djece i odraslih. Klinički se manifestira u obliku malih, umbiliciranih papula voštana sjaja. Dok su MC relativno česta u djece od 1. do 5. godine i mogu biti smještene bilo gdje na tijelu, njihova pojavnost u odraslih uglavnom se smatra spolno prenosivom infekcijom (engl. sexually transmitted infection, STI). MCV se može prenositi direktno s osobe na osobu ili autoinokulac...

  11. Phylogenetics, development, and Cenozoic paleontology of Buccinidae (Mollusca:Gastropoda)

    OpenAIRE

    Vendetti, Jann Elizabeth

    2009-01-01

    The buccinid gastropods (family Buccinidae) are a species-rich clade of mostly North Pacific taxa with an abundant fossil record that dates to the Cretaceous. Here, the evolution, systematics, and biology of fossil and extant members of this family are treated using a variety of analytical and methodological approaches. In chapter one, a new fossil species of Bruclarkia, an endemic eastern Pacific buccinid from the Eocene, Oligocene, and Miocene, is described from the Astoria Formation of the...

  12. A cladistic phylogeny of the family Patellidae (Mollusca: Gastropoda)

    Science.gov (United States)

    Ridgway, S. A.

    1998-01-01

    A phylogenetic hypothesis for the patellid limpets is reconstructed by cladistic analysis of morphological characters from 37 species, representing all but one of the living members of the family. Characters included in the analysis are derived from shell shape and microstructure, headfoot and pallial complex, radula and sperm. The species fall into four clades, providing the basis for a new phylogenetic classification into four monophyletic genera: Helcion (four species; southern Africa), Cymbula (eight species; southern Africa, eastern Atlantic, southern Indian Ocean), Scutellastra (17 species; southern and southwestern Africa, Australia, Indo-West Pacific, Eastern Pacific) and Patella (nine species; northeastern Atlantic and Mediterranean). The analysis suggests sister-group relationships between Helcion and Cymbula, and between Scutellastra and Patella. In combination with present-day patterns of geographical distribution, this phylogenetic hypothesis is used to discuss the historical biogeography of the Patellidae. Scutellastra may have originated in southern Africa and dispersed across the Pacific, or alternatively may be a primitively Tethyan group. Both Helcion and Cymbula appear to have originated in southern Africa, but three Cymbula species have dispersed respectively to northwest Africa, St Helena and the southern Indian Ocean. The patellids of the northeastern Atlantic form a single clade, Patella (including P. pellucida), which may have arrived by northward dispersal of an ancestor from southern Africa, or possibly by vicariance of a widespread ancestral Tethyan distribution. The known fossil record of patellids is too fragmentary to permit choice between these alternatives.

  13. Host specificity and phylogenetic relationships among Atlantic Ovulidae (Mollusca: Gastropoda)

    OpenAIRE

    Reijnen, B.T.; Hoeksema, B.W.; Gittenberger, E.

    2010-01-01

    Ovulid gastropods and their octocoral hosts were collected along the leeward coast of Curaçao, Netherlands Antilles. New molecular data of Caribbean and a single Atlantic species were combined with comparable data of Indo-Pacific Ovulidae and a single East-Pacific species from GenBank. Based on two DNA markers, viz. CO-I and 16S, the phylogenetic relationships among all ovulid species of which these data are available are reconstructed. The provisional results suggest a dichotomy between the ...

  14. New data on southern African Achatinidae (Mollusca, Gastropoda Pulmonata)

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1972-01-01

    Increasing knowledge of the genital anatomy of the species of the African land snail family Achatinidae has greatly improved our understanding of the delimitation of the species and the intricate interrelationships of the various taxa (Mead, 1950). The genitalia of many achatinids are still unknown

  15. Description of the ootheca of Turbinella laevigata (Mollusca, Gastropoda

    Directory of Open Access Journals (Sweden)

    Helena Matthews-Cascon

    2009-04-01

    Full Text Available Turbinella laevigata is found since the intertidal zone up to 40 m depth, being endemic of Brazil where it occurs from the state of Amapá to the state of Espirito Santo. The objective of this study was to describe the ootheca of this species. Fifteen samples collected in the Olho d'Água Beach, City of Icapuí and Fleixeiras Beach, City of Trairí, both in Ceará State, Northeast Brazil, were studied. The spawns were composed by 15 +/- 1.4 SD capsules and had 63 +/- 6.4 SD mm of length with 41 +/- 2.5 SD mm of width. They had a convex and a concave surface, and plaited edges that drew out until the basal membrane, to which they joined forming a medial ridge. This species apparently produced a high amount of nurse eggs. The early juveniles measured 6.4 +/- 0.7 SD mm of length and they presented a protoconch with three whorls.Turbinella laevigata é encontrada desde a zona entre marés até 40 m de profundidade, sendo endêmica do Brasil onde ocorre desde o Estado do Amapá até o Espírito Santo. O objetivo deste estudo foi descrever a ooteca de Turbinella laevigata. Quinze amostras foram coletadas na Praia de Olho d'Água, Município de Icapuí e na Praia de Flexeiras, Município do Trairí, ambos no Estado do Ceará, Nordeste do Brasil, foram estudadas. As desovas de T. laevigata foram compostas por 15 +/- 1.4 SD cápsulas e mediram 63 +/- 6.4 SD mm de comprimento e 41 +/- 2.5 SD mm de largura. Todas as cápsulas estavam fixadas pela membrana basal, a qual tinha a extremidade modificada para se prender ao substrato. Elas possuem uma superfície concava e outra convexa, apresentando margens pregueadas, que se prolongavam até a membrana basal, à qual se uniam formando uma prega. Esta espécie aparentemente produz uma grande quantidade de ovos nutritivos. A concha dos juvenis mediu 6.4 +/- 0.7 SD mm de comprimento e apresentou uma protoconcha com 3 voltas.

  16. New ultrastructural aspects of the spermatozoon of Aplysia depilans (Gastropoda, Opisthobranchia).

    Science.gov (United States)

    Vita, P; Corral, L; Azevedo, C

    2001-01-01

    The spermatozoon of the sea hare Aplysia depilans was studied under scanning (SEM) and transmission electron microscopy (TEM). Previous descriptions of this sperm and related species, both from light and electron microscopy, were inconsistent with each other. These descriptions include A. depilans, A. punctata, A. fasciata, A. kurodai and Bursatella leachiplei. Several detailed micrographs provide a new ultrastructural model and reveal new aspects such as the presence of acrosome and the absence of a glycogen piece, therefore the modified dense ring is the terminal structure. Results also show that previous models are incorrect in many aspects. The spermatozoon is a long slender uniflagellated cell with a complex helical structure and a length of approximately 165 microm. Observed in SEM the spermatozoon has an undifferentiated head and tail. The nucleus is cord-shaped and helically intertwined with the axoneme/mitochondrial derivative complex. The mitochondrial derivative has only one glycogen helix. Glycogen presence was demonstrated by Thiéry's method. Typical heterobranchia spermatozoa features are recognised. From bibliographic analysis, a high degree of similarity was found with the sperm of Pleurobranchea maculata (Notaspidea). PMID:11686398

  17. An annotated checklist of opisthobranch fauna (Gastropoda: Opisthobranchia of the Nicobar Islands, India

    Directory of Open Access Journals (Sweden)

    C.R. Sreeraj

    2012-04-01

    Full Text Available This paper presents 52 species of opisthobranchs recorded from the Nicobar group of Islands. Of these, Aldisa erwinkoehleri, Dermatobranchus rodmani, Glossodoris pallida, Noumea simplex, Pectenodoris trilineata, Okenia kendi, Tambja morosa, Phyllidia elegans, Phyllidiopsis annae, Flabellina riwo and Phidiana indica represent new records for Indian waters.

  18. Sperm tail differentiation in the nudibranch mollusc Hypselodoris tricolor (Gastropoda, Opisthobranchia).

    Science.gov (United States)

    Medina, A; Moreno, F J; García-Herdugo, G

    1988-06-01

    The sperm axoneme of Hypselodoris tricolor forms from a single centriole that is located initially beneath the plasma membrane and then migrates to the nuclear surface. A conspicuous centriolar adjunct-like formation is present in the neck of midspermatids, but it becomes very reduced at the end of spermiogenesis. In spermatocyte and spermatid mitochondria, intracristal bodies originate from the accumulation of a dense material in some cristae. From our observations and foregoing reports, it may be concluded that the process of sperm tail differentiation in opisthobranchs resembles that in pulmonates, whereas it differs in many respects from that occurring in prosobranchs. The appearance of intracristal bodies in modified mitochondria seems to be a special feature of spermatogenesis in the opisthobranchs that does not occur in the two other groups of gastropod molluscs. PMID:3235038

  19. Catecholamines and dihydroxyphenylalanine in metamorphosing larvae of the nudibranch Phestilla sibogae Bergh (Gastropoda: Opisthobranchia).

    Science.gov (United States)

    Pires, A; Coon, S L; Hadfield, M G

    1997-09-01

    The content of catecholamines and dihydroxyphenylalanine in larvae of the nudibranch Phestilla sibogae was analyzed by high-performance liquid chromatography with electrochemical detection. Dihydroxyphenylalanine, norepinephrine and dopamine were identified in larvae of all ages examined (5 through 12 days post-fertilization). Dihydroxyphenylalanine could be accurately quantified only in larvae of ages 8 through 12 days, when its average concentration increased from 0.62 to 6.71 x 10(-2) pmol micrograms protein-1. Between ages 5 and 12 days dopamine rose from 0.081 to 0.616 pmol microgram protein-1, and norepinephrine from 0.45 to 2.17 x 10(-2) pmol micrograms protein-1. Dihydroxyphenylalanine, dopamine and norepinephrine were also measured at different stages of metamorphic progress in 10- to 12-day larvae. Dihydroxyphenylalanine increased by a factor of 2.4 between the onset and completion of metamorphosis, but levels of dopamine and norepinephrine remained stable. One millimolar alpha-methyl-DL-m-tyrosine, an inhibitor of catecholamine synthesis, inhibited natural metamorphosis and depleted endogenous norepinephrine and especially dopamine, respectively, to 75% and 35% of control values. The existence of unexpectedly high levels of catecholamines in metamorphically competent larvae, and the association of catecholamine depletion with inhibition of metamorphosis, indicate that these compounds may participate in the control of gastropod development. PMID:9309865

  20. Larval rearing, metamorphosis, growth and reproduction of the eolid nudibranch hermissenda crassicornis (eschscholtz, 1831) (gastropoda: opisthobranchia).

    Science.gov (United States)

    Harrigan, J F; Alkon, D L

    1978-06-01

    1. Hermissenda crassicornis is a subannual nudibranch species that reproduces year-round. 2. There is a significant positive relationship between adult weight, diameter of the egg mass, estimated number of eggs per egg mass, and average number of eggs per capsule. 3. There is a planktonic veliger stage of 34 days minimum at 13 degrees -15 degrees C. 4. Larvae metamorphose on at least three species of hydroids. 5. To develop in reasonable numbers to a state competent to metamorphose veligers require a diet that includes phytoplankton of larger cell size (10-11 microm) than the commonly used Isochrysis and Monochrysis (5 microm). 6. Although Hermissenda feeds on a wide variety of sessile invertebrate species in the ocean, a diet of tunicate alone (Ciona intestinalis) promotes good growth and survival in the laboratory. 7. Egg mass deposition is initiated only after first copulation, except in the last month of life, and continues from about one-month post-metamorphosis to death, at about four months post-metamorphosis. Generation time (egg-to-egg) may be as short as 2.5 months. 8. A laboratory strain of Hermissenda is being established to provide animals of known history for research on the neural correlates of behavior. Animals, at least initially, are being selected for fast growth rate. PMID:20693369

  1. COMPARATIVE SPERM ULTRASTRUCTURE IN FIVE GENERA OF THE NUDIBRANCH FAMILY CHROMODORIDIDAE (GASTROPODA: OPISTHOBRANCHIA).

    Science.gov (United States)

    Wilson, NERIDA G.; Healy, JOHN M.

    2002-05-01

    Sperm ultrastructure is examined in representatives of five genera of the nudibranch gastropod family Chromodorididae: (Chromodoris, Hypselodoris, Glossodoris, Risbecia and Pectenodoris) and the results compared with previous work on other gastropods, especially other nudibranchs. As chromodoridid phylogeny is still incompletely understood, this study partly focuses on the search for new and as yet untapped sources of informative characters. Like spermatozoa of most other heterobranch gastropods, those of the Chromodorididae are elongate, complex cells composed of an acrosomal complex (small, rounded acrosomal vesicle, and columnar acrosomal pedestal), a condensed nucleus, sub-nuclear ring, a highly modified mid-piece (axoneme + coarse fibres surrounded by a glycogen-containing, helically-coiled mitochondrial derivative) and terminally a glycogen piece (or homologue thereof). The finely striated acrosomal pedestal is a synapomorphy of all genera examined here, but interestingly also occurs in at least one dorid (Rostanga arbutus). Substantial and potentially taxonomically informative differences were also observed between genera in the morphology of the nucleus, the neck region of the mid-piece, and also the terminal glycogen piece. The subnuclear ring is shown for the first time to be a segmented, rather than a continuous structure; similarly, the annular complex is shown to consist of two structures, the annulus proper and the herein-termed annular accessory body. PMID:12011239

  2. Reexamination of the gill withdrawal reflex of Aplysia californica Cooper (Gastropoda; Opisthobranchia).

    Science.gov (United States)

    Leonard, J L; Edstrom, J; Lukowiak, K

    1989-06-01

    The gill withdrawal reflex (GWR), an important model system for neural mechanisms of learning, varies in form and amplitude within as well as between preparations and is therefore a heterogeneous collection of action patterns, not a reflex. At least 4 action patterns occur in response to mechanical stimulation of the siphon. It is often impossible to categorize a particular movement unambiguously. All may occur spontaneously. Gill movements may be described as combinations of 10 actions; 4 involving vein movements are described here. All actions and action patterns can occur in preparations lacking the central nervous system. Some vein movements may generate considerable force without markedly altering gill area. It is suggested that this explains why some early studies failed to identify the important role of the peripheral nervous system in the GWR. Studies based on the assumption that the GWR involves a single type of movement controlled by cells of the parietovisceral ganglion require reevaluation. PMID:2544202

  3. New record of a headshield slug Phanerophthalmus smaragdinus (Gastropoda: Opisthobranchia from Andaman Islands, India

    Directory of Open Access Journals (Sweden)

    S. Narayana

    2013-04-01

    Full Text Available Opisthobranchs are the least studied group of marine gastropod molluscs in India. They are purely marine animals and display a wide array of colours and forms. This paper presents a new record of an opisthobranch, Phanerophthalmus smaragdinus, from Andaman Islands. The species was found inhabiting the intertidal area on rocks covered with green and brown algae.

  4. Pharyngeal movements during feeding sequences of Navanax inermis (Gastropoda: Opisthobranchia) in successive stages of dissection.

    Science.gov (United States)

    Susswein, A J; Achituv, Y; Cappell, M S; Bennett, M V

    1987-03-01

    Feeding in Navanax inermis Cooper was filmed and analysed after various dissections. In preparations with a cut through the body wall exposing the pharynx and buccal ganglia, completely normal feeding was observed. In addition to seven motor acts previously described in intact animals, an eighth act, peristalsis, was observed. In preparations with the pharynx excised from the animal but attached to the buccal ganglia, four motor acts were observed: flaring, expansion, contraction and peristalsis. In addition to increasing information about the nature of feeding movements in Navanax, these data indicate that preparations suitable for neurophysiological studies are capable of producing a variety of feeding acts. PMID:3559467

  5. Slugs' last meals: molecular identification of sequestered chloroplasts from different algal origins in Sacoglossa (Opisthobranchia, Gastropoda).

    Science.gov (United States)

    Händeler, Katharina; Wägele, Heike; Wahrmund, Ute; Rüdinger, Mareike; Knoop, Volker

    2010-11-01

    Some sacoglossan sea slugs have become famous for their unique capability to extract and incorporate functional chloroplasts from algal food organisms (mainly Ulvophyceae) into their gut cells. The functional incorporation of the so-called kleptoplasts allows the slugs to rely on photosynthetic products for weeks to months, enabling them to survive long periods of food shortage over most of their life-span. The algal food spectrum providing kleptoplasts as temporary, non-inherited endosymbionts appears to vary among sacoglossan slugs, but detailed knowledge is sketchy or unavailable. Accurate identification of algal donor species, which provide the chloroplasts for long-term retention is of primary importance to elucidate the biochemical mechanisms allowing long-term functionality of the captured chloroplast in the foreign animal cell environment. Whereas some sacoglossans forage on a variety of algal species, (e.g. Elysia crispata and E. viridis) others are more selective. Hence, characterizing the range of functional sacoglossan-chloroplast associations in nature is a prerequisite to understand the basis of this enigmatic endosymbiosis. Here, we present a suitable chloroplast gene (tufA) as a marker, which allows identification of the respective algal kleptoplast donor taxa by analysing DNA from whole animals. This novel approach allows identification of donor algae on genus or even species level, thus providing evidence for the taxonomic range of food organisms. We report molecular evidence that chloroplasts from different algal sources are simultaneously incorporated in some species of Elysia. NeigborNet analyses for species assignments are preferred over tree reconstruction methods because the former allow more reliable statements on species identification via barcoding, or rather visualize alternative allocations not to be seen in the latter. PMID:21565106

  6. Accumulation and identification of lipofuscin-like pigment in the neurons of Bulla gouldiana (Gastropoda: Opisthobranchia).

    Science.gov (United States)

    Robles, L J

    1978-01-01

    A few reports suggest that pigmented granules found in molluscan neurons accumulate with age as do lipofuscin granules in vertebrate cells; however, no reports on molluscan neurons include detailed descriptions of granule accumulation or histochemical tests to identify the pigment as lipofuscin-like. In this study light microscope observations of living ganglia from 1.7, 2.7, and 3.0 cm and larger (shell length) sized Bulla gouldiana showed an increasing accumulation of orange-red pigment in the perikaryon corresponding to increasing shell size (i.e. age). With the electron microscope similar results were obtained, and lipofuscin-like granules were seen in the nerve cell cytoplasm of veliger larvae and in all adult sized Bulla. Staining with Sudan black B, Nile blue, chrome alum hematoxylin, PAS reagents, and exposure of the neurons to u.v. light to observe subsequent autofluorescence, yielded positive results in the areas of pigmented granule accumulation. Thus, the brillant orange-red granules that accumulate with age in the peripheral cytoplasm of adult Bulla neurons, and which are probably also present in larval stages, chemically resemble the lipofuscin granules of vertebrates. Similarities and differences between molluscan pigmented granules and vertebrate lipofuscin granules, in relation to structure and mechanisms of development and accumulation, are discussed. PMID:625150

  7. Foraminiferans as food for Cephalaspideans (Gastropoda: Opisthobranchia), with notes on secondary tests around calcareous foraminiferans

    DEFF Research Database (Denmark)

    Cedhagen, Tomas

    1996-01-01

    The food of four species of Cephalaspidea (Philine aperta, Philine denticulata, Philine scabra and Cylichna cylindracea) was studied in animals collected on silty clay bottoms at 20-35 m depth on the west coast of Sweden. The specimens were dissected. Only calcareous foraminiferans were found in...... agglutinating foraminiferans surround themselves with a “secondary test”, a cyst or covering of foreign particles around the test. This structure has earlier been called a “reproductive cyst” or “feeding cyst” in some species. “Secondary tests” are primarily connected with feeding, but might also be a...... preadaptation for other purposes. It might, in species like Ammonia batavus, have become a kind of antipredatory device or mimicry. A predator might conceive such a species as an agglutinating species and neglect it. The secondary test is a delicate structure in most species and is easily destroyed by the rough...

  8. Keeping Nerves: Central Nervous System of the Interstitial Acochlidiid Parhedyle cryptophthalma (Gastropoda, Opisthobranchia)

    DEFF Research Database (Denmark)

    Joerger, Katharina; Kristof, Alen; Klussmann-Kolb, Annette;

    2008-01-01

    Unusually well-preserved fossils of a Halicyne-like cycloid crustacean frequently occur in the early Late Triassic lacustrine clay bed at Krasiejów in Opole Silesia, southern Poland. Its gill-like structures form a horseshoe-shaped pair of units composed of numerous calcified blades with reverse ...

  9. The phylogenetic position of a new species of Plakobranchus from West Papua, Indonesia (Mollusca, Opisthobranchia, Sacoglossa).

    Science.gov (United States)

    Meyers-Muñoz, María Angélica; van der Velde, Gerard; van der Meij, Sancia E T; Stoffels, Bart E M W; van Alen, Theo; Tuti, Yosephine; Hoeksema, Bert W

    2016-01-01

    Plakobranchus papua Meyers-Muñoz & van der Velde, sp. n. from West Papua (Papua Barat province, Indonesia), is described based on its external morphology, colour pattern, internal anatomy, radula and reproductive system. In a molecular phylogenetic study specimens of this new species were compared with those of ten candidate taxa under the name Plakobranchus ocellatus van Hasselt, 1824. DNA analyses of COI mtDNA showed a clear distinction between Plakobranchus papua sp. n. and "Plakobranchus ocellatus". Plakobranchus papua, sp. n. also differed from all taxa that have been synonymised with Plakobranchus ocellatus. The genus is in dire need of taxonomic revision, preferably based on an integrative analysis involving morphology and DNA of all known Plakobranchus varieties. PMID:27408559

  10. Histochemical and ultrastructural characterization of the posterior esophagus of Bulla striata (Mollusca, Opisthobranchia).

    Science.gov (United States)

    Lobo-da-Cunha, Alexandre; Oliveira, Elsa; Ferreira, Iris; Coelho, Rita; Calado, Gonçalo

    2010-12-01

    The posterior esophagus of Bulla striata, running from the gizzard to the stomach, was investigated with light and electron microscopy to obtain new data for a comparative analysis of the digestive system in cephalaspidean opisthobranchs. In this species, the posterior esophagus can be divided into two regions. In the first, the epithelium is formed by columnar cells with apical microvilli embedded in a cuticle. Many epithelial and subepithelial secretory cells are present in this region. In both, electron-lucent secretory vesicles containing filaments and a peripheral round mass of secretory material fill the cytoplasm. These acid mucus-secreting cells may also contain a few dense secretory vesicles. In the second part of the posterior esophagus, the cuticle is absent and the epithelium is ciliated. In this region, epithelial cells may contain larger lipid droplets and glycogen reserves. Subepithelial secretory cells are not present, and in epithelial secretory cells the number of dense vesicles increases, but most secretory cells still contain some electron-lucent vesicles. These cells secrete a mixture of proteins and acid polysaccharides and should be considered seromucous. The secretory cells of the posterior esophagus are significantly different from those previously reported in the anterior esophagus of this herbivorous species. PMID:20883598

  11. Patterns of neural and behavioral activity in freely-moving Navanax inermis (Mollusca; Opisthobranchia).

    Science.gov (United States)

    Leonard, J L

    1992-01-01

    As part of an ongoing neuroethological study of complex behavior in the opisthobranch mollusc, Navanax inermis, I have extended the available gross anatomical descriptions and used cuff electrodes to obtain chronic recordings from whole nerves or connectives. The major anatomical findings concern a) finer branches of the pedal nerves, particularly P3C P4 and P5; b) the distribution of nerves from the abdominal and subintestinal ganglia; and c) a possible neurohaemal area of the supraintestinal ganglion. With cuff electrodes it has been possible to get good quality recordings (often with spikes in the mv range) during the full repertoire of sexual, predatory and cannibalistic behaviors. The high degree of cryptic neural activity and the fact that in Navanax behaviors are not mutually exclusive, make it difficult to identify one-to-one correspondences between behaviors and neural patterns, However, there is an apparent correlation between the activity of a very large unit(s) on P5 and an exploratory behavior, the Face-Down head posture when it is directed at the substrate rather than prey, or a conspecific. PMID:1299122

  12. Light and electron microscopy studies of the oesophagus and crop epithelium in Aplysia depilans (Mollusca, Opisthobranchia).

    Science.gov (United States)

    Lobo-da-Cunha, Alexandre; Batista-Pinto, Carla

    2005-12-01

    The oesophagus and crop epithelium of Aplysia depilans consist in a single layer of columnar cells with apical microvilli, and some of them also possess cilia. Cell membrane invaginations, small vesicles, multivesicular bodies and many dense lysosomes were observed in the apical region of the cytoplasm. In most cells, a very large lipid droplet was observed above the nucleus and a smaller one was frequently found below the nucleus; glycogen granules are also present. Considering these ultrastructural features, it seems that these cells collect nutritive substances from the lumen by endocytosis, digest them in the apical lysosomes and store the resulting products. The cell bodies of mucus secreting flask-shaped cells are subepithelial in the oesophagus and intraepithelial in the crop. Histochemistry methods showed that the secretion stored in these cells contains acidic polysaccharides. Secretory vesicles with thin electron-dense filaments scattered in an electron-lucent background fill most of these cells, and the basal nucleus is surrounded by dilated rough endoplasmic reticulum cisternae containing small tubular structures. Considering the relatively low number of secretory cells, mucus production cannot be high. Moreover, since protein secreting cells were not observed in either oesophagus or crop, extracellular digestion in the lumen of these anterior segments of the digestive tract most probably depend on the enzymes secreted by the salivary and digestive glands. PMID:16260017

  13. 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, a...

  14. Stomach of Aplysia depilans (Mollusca, Opisthobranchia): a histochemical, ultrastructural, and cytochemical study.

    Science.gov (United States)

    Lobo-da-Cunha, Alexandre; Batista-Pinto, Carla

    2003-06-01

    We report the results of a morphological, histochemical, and cytochemical characterization of the Aplysia depilans stomach, an organ little studied in opisthobranchs. Very thin ciliated cells with microvilli on their apical surfaces are predominant in the epithelium lining the lumen of the stomach. Many lysosomes with a strong arylsulphatase activity were present in the apical regions of these cells that could also contain some lipid droplets and glycogen. Small peroxisomes were observed, usually around lipid droplets or mitochondria. Bottle-shaped secretory cells are very common in this epithelium and produce a secretion rich in proteins and acidic mucopolysaccharides. Most of the cytoplasm of these mucus-producing cells was filled with a very high number of granules and the nucleus is dislocated to the basal region. Cisternae of rough endoplasmic reticulum were abundant around the nucleus and several Golgi stacks were also present in this area. In spite of the variation in the electron density of the granules, only one type of secretory cell seems to be present in the stomach epithelium, since granules with very different electron densities were frequently found in the same cell. A few neurons were also found in the stomach epithelium of this species. Fibrocytes, muscle cells, nerves, and amebocytes were observed in the connective tissue of the stomach wall. PMID:12655617

  15. The digestive cells of the hepatopancreas in Aplysia depilans (Mollusca, Opisthobranchia): ultrastructural and cytochemical study.

    Science.gov (United States)

    Lobo-da-Cunha, A

    2000-02-01

    Digestive cells are the most abundant cell type in the digestive diverticula of Aplysia depilans. These are tall columnar or club shaped cells, covered with microvilli on their apical surface. A large number of endocytic vesicles containing electron-dense substances can be found in the apical zone, but the presence of many heterolysosomes of large diameter is the main feature of these cells. Glycogen particles and some lipid droplets were also observed. Peroxisomes with a circular or oval profile were common, but crystalline nucleoids were not detected in them, although a dense spot in the matrix was observed in a few cases. These organelles were strongly stained after cytochemical detection of catalase activity. The Golgi stacks are formed by 4 or 5 cisternae, with dilated zones containing electron dense material. Arylsulphatase activity was detected in the Golgi stacks and also in lysosomes. Cells almost entirely occupied by a very large vacuole containing a residual dense mass seem to be digestive cells in advanced stages of maturation. The observation of semithin and ultrathin sections indicates that these very large vacuoles are the result of a fusion among the smaller lysosomes. Some images suggest that the content of these large vacuoles is extruded into the lumen of the digestive diverticula. PMID:10798317

  16. Embryonic development of nudibranch species (Mollusca:Opisthobranchia) in the Gulf of Thailand

    Institute of Scientific and Technical Information of China (English)

    Pattira Kasamesiri; Shettapong Meksumpun; Charumas Meksumpun

    2014-01-01

    Objective: To find the possible way to predict the mode of embryonic development of nudibranchs, focusing on egg mass characteristics, embryonic development, and shell patterns of the veligers.Methods:The specimens were allowed to copulate and lay their egg masses under laboratory conditions. Embryonic development was monitored under a light microscope with a digital camera every day until hatching.Results:Eight species of nudibranch were collected in the eastern part of the Gulf of Thailand. that developed, except for Jorunna funebris, which had 1-4 larvae in each egg capsule. All the specimens had the same pattern of cell division and hatching into the water column during the veliger form. However, the species developed at different rates in each stage. Most of the species of nudibranch collected had a single larva in each egg capsule Conclusions: All species in the current study had planktotrophic development except Doriprismatica atromarginata, which showed lecithotrophic development. Based on embryonic development among the nudibranchs that showed planktotrophic development, Jorunna funebris appeared to be the most advantageous species for culture development with regard to utilization and conservation in the future.

  17. Embryonic development of nudibranch species (Mollusca: Opisthobranchia in the Gulf of Thailand

    Directory of Open Access Journals (Sweden)

    Pattira Kasamesiri

    2014-12-01

    Full Text Available Objective: To find the possible way to predict the mode of embryonic development of nudibranchs, focusing on egg mass characteristics, embryonic development, and shell patterns of the veligers. Methods: Eight species of nudibranch were collected in the eastern part of the Gulf of Thailand. The specimens were allowed to copulate and lay their egg masses under laboratory conditions. Embryonic development was monitored under a light microscope with a digital camera every day until hatching. Results: Most of the species of nudibranch collected had a single larva in each egg capsule that developed, except for Jorunna funebris, which had 1-4 larvae in each egg capsule. All the specimens had the same pattern of cell division and hatching into the water column during the veliger form. However, the species developed at different rates in each stage. Conclusions: All species in the current study had planktotrophic development except Doriprismatica atromarginata, which showed lecithotrophic development. Based on embryonic development among the nudibranchs that showed planktotrophic development, Jorunna funebris appeared to be the most advantageous species for culture development with regard to utilization and conservation in the future.

  18. A new record of Morula anaxares with a description of the radula of three other species from Goa, Central West Coast of India (Gastropoda: Muricidae)

    Digital Repository Service at National Institute of Oceanography (India)

    Kumbhar, J.V.; Rivonker, C.U.

    of Madras. Journal of the Bombay Natural History Society, 42: 323-341, pls. 1-4. Egorov, R. V. 1993. Trophoninae (Muricidae) of Russian and adjacent waters. Ruthenica Supplement, 48 pp. Gravely, F. H. 1942. Shells and other animal remains found... of Lakshadweep, Mollusca: State Fauna ser., 2: 273-362, 3 pls. Rao, N. V. S. 2003. Indian seashells (Part- I): Polyplacophora and Gastropoda, Records of the Zoological Survey of India, Occasional Paper 19: 416 pp. Rao, N. V. S. and Rao, K. V. S. 1993...

  19. Fauna Europaea: Mollusca - Bivalvia.

    Science.gov (United States)

    Araujo, Rafael; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. For the Mollusca-Bivalvia, data from 5 families (Margaritiferidae, Unionidae, Sphaeriidae, Cyrenidae, Dreissenidae) containing 55 species are included in this paper. 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 (Corbiculafluminea) and the Dreissenoidea the famous invasive zebra mussel (Dreissenapolymorpha). Basic information is summarized on their taxonomy and biology. Tabulations include a complete list of the current estimated families, genera and species.

  20. Digestive system of the sacoglossan Plakobranchus ocellatus (Gastropoda: Opisthobranchia): light- and electron-microscopic observations with remarks on chloroplast retention.

    Science.gov (United States)

    Hirose, Euichi

    2005-08-01

    The sacoglossan Plakobranchus ocellatus feeds by sucking the cytoplasmic contents from algae and retains intact algal chloroplasts within the cells of the digestive gland. Morphology of the entire digestive system of this species was firstly described by means of a combination of histology and electron microscopy (both SEM and TEM). The short alimentary canal is confined to the head, and the anus opens at the anterior right corner of the pericardial swelling, as is the case in many non-shelled sacoglossans. The alimentary canal of the specimens examined rarely contained ingesta, suggesting that the retained chloroplasts provide sufficient nourishment to the sacoglossan hosts and that sea slugs with empty stomachs survive well in the field. The digestive gland, with the retained chloroplasts, branches from the stomach and is sparsely distributed throughout the body, including the head region, but is aggregated mainly in the dorsal lamellae. Chloroplasts were occasionally found in the epithelial cells in the transitional region from the stomach wall to the digestive gland, which may be a site at which chloroplasts are incorporated into the animal cells by endocytosis. Numerous microvilli filling the lumen of the digestive gland suggest that molecules are actively transferred within the gland. The sea slug thus apparently provides a favorable environment to support the long-term retention and function of chloroplasts. PMID:16141704

  1. mtDNA ribosomal gene phylogeny of sea hares in the genus Aplysia (Gastropoda, Opisthobranchia, Anaspidea): Implications for comparative neurobiology

    Energy Technology Data Exchange (ETDEWEB)

    Medina, Monica; Collins, Timothy M.; Walsh, Patrick J.

    2000-08-10

    Sea hares within the genus Aplysia are important neurobiological model organisms, and as studies based on different Aplysia species appear in the literature, a phylogenetic framework has become essential. We present a phylogenetic hypothesis for this genus, based on portions of two mitochondrial genes (12S and 16S). In addition, we reconstruct the evolution of several behavioral characters of interest to neurobiologists in order to illustrate the potential benefits of a phylogeny for the genus Aplysia. These benefits include the determination of ancestral traits, the direction and timing of evolution of characters, prediction of the distribution of traits, and identification of cases of independent acquisition of traits within lineages. This last benefit may prove especially useful in understanding the linkage between behaviors and their underlying neurological basis.

  2. Analysis of nitric oxide-cyclic guanosine monophosphate signaling during metamorphosis of the nudibranch Phestilla sibogae Bergh (Gastropoda: Opisthobranchia).

    Science.gov (United States)

    Bishop, Cory D; Pires, Anthony; Norby, Shong-Wan; Boudko, Dmitri; Moroz, Leonid L; Hadfield, Michael G

    2008-01-01

    The gas nitric oxide (NO), and in some cases its downstream second messenger, cyclic guanosine monophosphate (cGMP) function in different taxa to regulate the timing of life-history transitions. Increased taxonomic sampling is required to foster conclusions about the evolution and function of NO/cGMP signaling during life-history transitions. We report on the function and localization of NO and cGMP signaling during metamorphosis of the nudibranch Phestilla sibogae. Pharmacological manipulation of NO or cGMP production in larvae modulated responses to a natural settlement cue from the coral Porites compressa in a manner that suggest inhibitory function for NO/cGMP signaling. However, these treatments were not sufficient to induce metamorphosis in the absence of cue, a result unique to this animal. We show that induction of metamorphosis in response to the settlement cue is associated with a reduction in NO production. We documented the expression of putative NO synthase (NOS) and the production of cGMP during larval development and observed no larval cells in which NOS and cGMP were both detected. The production of cGMP in a bilaterally symmetrical group of cells fated to occupy the distal tip of rhinophores is correlated with competence to respond to the coral settlement cue. These results suggest that endogenous NO and cGMP are involved in modulating responses of P. sibogae to a natural settlement cue. We discuss these results with respect to habitat selection and larval ecology. PMID:18460091

  3. mtDNA ribosomal gene phylogeny of sea hares in the genus Aplysia (Gastropoda, Opisthobranchia, Anaspidea): implications for comparative neurobiology.

    Science.gov (United States)

    Medina, M; Collins, T M; Walsh, P J

    2001-01-01

    Sea hares within the genus Aplysia are important neurobiological model organisms; as more studies based on different Aplysia species are appearing in the literature, a phylogenetic framework has become essential. We present a phylogenetic hypothesis for this genus, based on portions of two mitochondrial genes (12S and 16S). In addition, we reconstruct the evolution of several behavioral characters of interest to neurobiologists to illustrate the potential benefits of a phylogeny for the genus Aplysia. These benefits include determination of ancestral traits, direction and timing of evolution of characters, prediction of the distribution of traits, and identification of cases of independent acquisition of traits within lineages. This last benefit may prove especially useful in understanding the linkage between behaviors and their underlying neurological bases. PMID:12116938

  4. The sudden appearance of Aeolidiella glauca (Gastropoda: Opisthobranchia) in lake Greveliningen (S.W. Netherlands) in 1983 and 1984

    NARCIS (Netherlands)

    Dekker, R.

    1985-01-01

    In 1983 and 1984 a population of the nudibranch Aeolidiella glauca (Alder & Hancock, 1845) was found in the saline Lake Grevelingen (S.W. Netherlands). The number of specimens observed exceeds by far the total number previously recorded from the Dutch coast. Field observations on food intake suggest

  5. Impacts associated with the recent range shift of the aeolid nudibranch Phidiana hiltoni (Mollusca, Opisthobranchia) in California.

    Science.gov (United States)

    Goddard, Jeffrey H R; Gosliner, Terrence M; Pearse, John S

    2011-01-01

    In 1977, Phidiana hiltoni (O'Donoghue in J. Entomol Zool (Pomona College, Claremont, California) 19:77-119, 1927) began spreading northward from Monterey, California. By 1992, it had reached Duxbury Reef (37° 53' 23″ N, 122° 41' 59″ W), 100 km to the north, where other nudibranchs subsequently appeared to decline. The role of P. hiltoni in this decline was investigated through diet analysis, feeding trials, and comparison of historical and recent abundance data. In the wild, P. hiltoni preyed largely on hydroids, but also showed evidence of predation on nudibranchs. In the laboratory, P. hiltoni attacked most of the dendronotid and aeolid nudibranchs presented to it, ingesting small individuals whole. The pooled abundance of nudibranchs vulnerable to attack by P. hiltoni declined an average of two-thirds at Duxbury Reef since its arrival, compared to (1) no change in the non-vulnerable species and (2) no change in either group at two other sites where P. hiltoni was one to two orders of magnitude less abundant. Phidiana hiltoni therefore appears to have caused this decline, likely through a combination of direct predation and competition for prey. A brief larval period, combined with cyclonic re-circulation in the lee of Point Reyes, may be driving self-recruitment of P. hiltoni at Duxbury Reef, as well as hindering further northward spread. PMID:24391265

  6. Ultrastructural and cytochemical aspects of the basophilic cells in the hepatopancreas ofAplysia depilans(Mollusca, Opisthobranchia).

    Science.gov (United States)

    Lobo-da-Cunha, A

    1999-02-01

    The basophilic cells ofAplysia depilanshave a pyramidal shape and a large nucleus usually located near the center or in the basal half of the cell. The nucleus possesses several clumps of condensed chromatin and a prominent nucleolus. The great profusion of rough endoplasmic reticulum cisterns in a major feature of these cells. Secretion granules are accumulated in the apical zone, and arylsulphatase was detected in some of them. In some basophilic cells a very substantial part of the cell volume was occupied by clear vacuoles, some of them reaching 9 mum. However, in other cells only a few vacuoles were observed. Probably the cells with just a few vacuoles are still young, and after a progressive accumulation, the vacuoles become abundant in old cells. The presence of a dark nucleus in the cells with a large number of vacuoles suggests that they are in a final stage of their life. Arylsulphatase was detected in the vacuoles and also in small secondary lysosomes containing substances in digestion. Bundles of tubules with 50 nm in diameter were found within some cisterns of rough endoplasmic reticulum. A cell fraction enriched in mannitol oxidase, extracted from the hepatopancreas of a terrestrial slug, consisted in very similar tubular structures. Using a histochemical method, mannitol oxidase was detected in the basophilic cells ofA. depilans, and it may be associated with the tubular structures of the endoplasmic reticulum. This is the first report of mannitol oxidase in opisthobranch molluscs. Almost spherical peroxisomes with a small nucleoid were abundant in these cells. The nucleoids presented a rectangular section, but a crystalline structure was not evident. The peroxisomes were stained after the cytochemical detection of catalase activity. PMID:18627851

  7. Sperm ultrastructure in the nudibranch genus Halgerda with reference to other Discodorididae and to Chromodorididae (Mollusca: Opisthobranchia).

    Science.gov (United States)

    Fahey, Shireen J; Healy, John M

    2003-07-01

    Comparative sperm ultrastructure within the molluscan nudibranch genus Halgerda (Discodorididae) was examined for the first time using transmission electron microscopy (TEM), based on 17 of the 35 known species. In addition, observations on two other discodorids are made to facilitate outgroup comparison with Halgerda, including one species of Discodoris (D. boholiensis) and Asteronotus cespitosus (currently accepted as the closest sister taxon to Halgerda). Comparison was also made with some genera of the Chromodorididae in view of sperm similarities. Spermatozoa of all species examined were of the complex, helical, elongate ( approximately 300-400 micro m) type characteristic of most heterobranch gastropods. These cells exhibit the following discrete regions (in anteroposterior sequence) : an acrosomal complex (composed of a rounded, membrane-bound vesicle and a column-like pedestal); a solid, helical nucleus; an elongate, helical midpiece (composed of an axoneme and associated nine coarse fibers, an enveloping mitochondrial derivative of matrix, and paracrystalline materials and glycogen helix); an annular complex; and a short glycogen piece. Of these regions, the midpiece is by far the longest, occupying over 90% of the total sperm length. Comparison with other members of the radula-bearing cryptobranch dorids reveals several sperm similarities to other genera in the clade, particularly those of other Discodorididae and also with the Chromodorididae. Comparison with previously studied genera reveals noteworthy sperm differences within the Discodorididae. The most notable differences are the internal structure of the acrosomal pedestal (long and homogeneous in Halgerda, Discodoris; short and homogeneous in Asteronotus; long and finely striated in Rostanga; oblong with angular electron-lucent striations in Jorunna) and the internal structure of the glycogen piece. The pronounced helical keels of most Halgerda and Discodoris nuclei contrast with the weakly helical nucleus of Asteronotus. Sperm features alone do not provide a means of defining the genus Halgerda or the family Discodorididae nor do they support the monophyletic status of the caryophyllidia-bearing dorids. Important sperm characters such as the acrosome, nucleus, and midpiece can often still be determined from specimens that have been initially fixed in formalin, then stored in ethanol for extended periods of time (i.e., museum material). Of all sperm features, the mitochondrial derivative of the midpiece is the most resistant to long-term fixation : the survival of acrosomal, nuclear, and axonemal components is variable, presumably a factor of prefixation autolysis, varied primary fixation times and temperatures, formalin quality, and duration of alcohol storage. PMID:12740892

  8. The Cylindrobulla/Ascobulla complex--unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species.

    Science.gov (United States)

    Laetz, Elise; Christa, Gregor; Händeler, Katharina; Wägele, Heike

    2014-01-01

    Sacoglossa (Gastropoda: Heterobranchia) are generally considered a monophyletic group, previously associated within the now defunct "Opisthobranchia", but now basally located within Panpulmonata. In the light of this new phylogenetic hypothesis, detailed knowledge of the most basal groups within Sacoglossa is of paramount importance. This study focuses on the genus Cylindrobulla, which is usually considered the most basal group within the Sacoglossa from a morphological point of view, because it does not share the typical elongate radula teeth of all other Sacoglossa. We describe a new species, Cylindrobulla schuppi sp. nov., and provide data on its food. We reexamined and clarify the radula of the type species C. beauii, review the genus with all other valid species, provide new characters to aid in the proper identification of species within this genus, compare it to the very similar genus Ascobulla, present a determination key using external characters to ensure proper identification of the two similar genera, and discuss phylogenetic relationships within the shelled sacoglossan, the Oxynoacea. PMID:25544526

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

    NARCIS (Netherlands)

    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).

  10. A new species of hydrobiid snails (Mollusca, Gastropoda, Hydrobiidae from central Greece

    Directory of Open Access Journals (Sweden)

    Canella Radea

    2011-10-01

    Full Text Available A new minute valvatiform species belonging to the genus Daphniola Radoman 1973, Daphniola eptalophos sp. n., from mountain Parnassos, Greece is described. The new species has a transparent valvatiform-planispiral shell, wide and open umbilicus, grey-black pigmented soft body and head and a black penis with a small colorless outgrowth on the left side near its base. A comparative table of shell dimensions and a key to the species known for this endemic genus for Greece are provided.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 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 jud

  13. Vitrinellidae (Marine Mollusca Gastropoda) from Holocene deposits in Surinam (Dutch Guiana)

    NARCIS (Netherlands)

    Regteren Altena, van C.O.

    1966-01-01

    Five species of Vitrinellidae have been found in the Holocene shell ridges of Surinam. Of these, Vitrinella (Striovitrinella) cupidinensis,Cochliolepis surinamensis, and Solariorbis guianensis are new species, while Cyclostremiscus caraboboensis Weisbord is known from Pliocene beds in Venezuela and

  14. Mitochondrial DNA hyperdiversity and its potential causes in the marine periwinkle Melarhaphe neritoides (Mollusca: Gastropoda)

    Science.gov (United States)

    Mardulyn, Patrick; Hardy, Olivier J.; Jordaens, Kurt; de Frias Martins, António Manuel; Backeljau, Thierry

    2016-01-01

    We report the presence of mitochondrial DNA (mtDNA) hyperdiversity in the marine periwinkle Melarhaphe neritoides (Linnaeus, 1758), the first such case among marine gastropods. Our dataset consisted of concatenated 16S-COI-Cytb gene fragments. We used Bayesian analyses to investigate three putative causes underlying genetic variation, and estimated the mtDNA mutation rate, possible signatures of selection and the effective population size of the species in the Azores archipelago. The mtDNA hyperdiversity in M. neritoides is characterized by extremely high haplotype diversity (Hd = 0.999 ± 0.001), high nucleotide diversity (π = 0.013 ± 0.001), and neutral nucleotide diversity above the threshold of 5% (πsyn = 0.0677). Haplotype richness is very high even at spatial scales as small as 100m2. Yet, mtDNA hyperdiversity does not affect the ability of DNA barcoding to identify M. neritoides. The mtDNA hyperdiversity in M. neritoides is best explained by the remarkably high mutation rate at the COI locus (μ = 5.82 × 10−5 per site per year or μ = 1.99 × 10−4 mutations per nucleotide site per generation), whereas the effective population size of this planktonic-dispersing species is surprisingly small (Ne = 5, 256; CI = 1,312–3,7495) probably due to the putative influence of selection. Comparison with COI nucleotide diversity values in other organisms suggests that mtDNA hyperdiversity may be more frequently linked to high μ values and that mtDNA hyperdiversity may be more common across other phyla than currently appreciated. PMID:27761337

  15. Biological aspects of Omalonyx convexus (Mollusca, Gastropoda, Succineidae from the Rio Grande do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Janine Oliveira Arruda

    2011-12-01

    Full Text Available Omalonyx convexus (Heynemann, 1868 is widely spread throughout the Rio Grande do Sul State, Brazil. The studied specimens presented in vivo, tegument and mantle coloring in variations between milky-white, orange and beige. The shell presented itself covered by the mantle in different extents; however, it was not completely covered on any of the specimens. The feeding diet is basically constituted by vegetal tissues, although non-vegetal food items were also found. The specimens were found in preserved and in polluted fresh water environments, as well as on natural and artificial substrates. The temperature throughout the day influences their placement on habitat substrates.

  16. Mitochondrial genome of the endangered marine gastropod Strombus gigas Linnaeus, 1758 (Mollusca: Gastropoda).

    Science.gov (United States)

    Márquez, Edna J; Castro, Erick R; Alzate, Juan F

    2016-01-01

    The queen conch Strombus gigas is an endangered marine gastropod of significant economic importance across the Greater Caribbean region. This work reports for the first time the complete mitochondrial genome of S. gigas, obtained by FLX 454 pyrosequencing. The mtDNA genome encodes for 13 proteins, 22 tRNAs and 2 ribosomal RNAs. In addition, the coding sequences and gene synteny were similar to other previously reported mitogenomes of gastropods. PMID:25186797

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

    Directory of Open Access Journals (Sweden)

    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.

  18. On Cyprian Helicellinae (Mollusca: Gastropoda Pulmonata: Helicidae), making a new start

    NARCIS (Netherlands)

    Gittenberger, E.

    1991-01-01

    Our fragmentary knowledge concerning the Cyprian Helicellinae is revised and summarized, while new data are added. "Helicella (Xerotricha) conspurcata distinguenda" Haas, 1936, is a Helicopsis species that has to be called H. cypriola (Westerlund, 1889) as a consequence of the selection of a neotype

  19. The aquatic molluscs (Mollusca: Gastropoda and Bivalvia of Vrachanski Balkan Nature Park

    Directory of Open Access Journals (Sweden)

    DILIAN GEORGIEV

    2016-05-01

    Full Text Available Till now 13 species of aquatic molluscs are known to inhabit the park area: 11 species of snails and 2 species of clams. Even included in the list the species of Grossuana and Radix balthica has to be studied anatomically for sure identification. Nine species are of conservation statute classified as "Least Concern" or "Vulnerable", and four does not have any statute. Three stygobiotic snail species are local endemics.

  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. Anatomia e histologia do conduto genital feminino 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 genital duct in mature and immature females of Pomacea canaliculata (Lamarck, 1822. Anatomically, the vagina has an equal dimension in its extension, varying in form and volume, according to the maturation period. In the immaturity, it has a smaller diameter and volume. In the maturity, the vagina increases in volume, having the aspect of a tumescent organ, and in certain specimens shows an albuminous pink thread in its lumen. Histologically, the calcigenic activity of the gland is evidentiated by the presence of an amorphous and basophilic mass, without nuclear material. This material has a fragmented aspect in the vagina lumen that reacts positively in van Kossa's coloured preparations for calcareous salts.

  2. The venomous cocktail of the vampire snail Colubraria reticulata (Mollusca, Gastropoda)

    OpenAIRE

    Modica, Maria Vittoria; Lombardo, Fabrizio; Franchini, Paolo; Oliverio, Marco

    2015-01-01

    Background Hematophagy arose independently multiple times during metazoan evolution, with several lineages of vampire animals particularly diversified in invertebrates. However, the biochemistry of hematophagy has been studied in a few species of direct medical interest and is still underdeveloped in most invertebrates, as in general is the study of venom toxins. In cone snails, leeches, arthropods and snakes, the strong target specificity of venom toxins uniquely aligns them to industrial an...

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

    DEFF Research Database (Denmark)

    Kristof, Alen; Klussmann-Kolb, Annette

    2010-01-01

    to metamorphosis. The postmetamorphic central nervous system (CNS) becomes concentrated, and the rhinophoral ganglia develop together with the anlage of the future rhinophores whereas oral tentacle ganglia are not found. The myogenesis in A. stephanieae begins with the larval retractor muscle followed...

  4. Size clines and subspecies in the Streptaxid Genus Gulella PFR. (Mollusca, Gastropoda pulmonata) in Southern Africa

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1980-01-01

    CONTENTS 1. Introduction.................. 3 2. Systematic part................. 6 Gulella adamsiana................. 7 Gulella darglensis................. 14 Gulella elliptica................. 19 Gulella farquhari................. 27 Gulella infrendens................ 33 Gulella planti.............

  5. 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. I

  6. Evaluation of the cholinomimetic actions of trimethylsulfonium, a compound present in the midgut gland of the sea hare Aplysia brasiliana (Gastropoda, Opisthobranchia

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    C.M. Kerchove

    2002-04-01

    Full Text Available Trimethylsulfonium, a compound present in the midgut gland of the sea hare Aplysia brasiliana, negatively modulates vagal response, indicating a probable ability to inhibit cholinergic responses. In the present study, the pharmacological profile of trimethylsulfonium was characterized on muscarinic and nicotinic acetylcholine receptors. In rat jejunum the contractile response induced by trimethylsulfonium (pD2 = 2.46 ± 0.12 and maximal response = 2.14 ± 0.32 g was not antagonized competitively by atropine. The maximal response (Emax to trimethylsulfonium was diminished in the presence of increasing doses of atropine (P<0.05, suggesting that trimethylsulfonium-induced contraction was not related to muscarinic stimulation, but might be caused by acetylcholine release due to presynaptic stimulation. Trimethylsulfonium displaced [³H]-quinuclidinyl benzilate from rat cortex membranes with a low affinity (Ki = 0.5 mM. Furthermore, it caused contraction of frog rectus abdominis muscles (pD2 = 2.70 ± 0.06 and Emax = 4.16 ± 0.9 g, which was competitively antagonized by d-tubocurarine (1, 3 or 10 µM with a pA2 of 5.79, suggesting a positive interaction with nicotinic receptors. In fact, trimethylsulfonium displaced [³H]-nicotine from rat diaphragm muscle membranes with a Ki of 27.1 µM. These results suggest that trimethylsulfonium acts as an agonist on nicotinic receptors, and thus contracts frog skeletal rectus abdominis muscle and rat jejunum smooth muscle via stimulation of postjunctional and neuronal prejunctional nicotinic cholinoreceptors, respectively.

  7. Evaluation of the cholinomimetic actions of trimethylsulfonium, a compound present in the midgut gland of the sea hare Aplysia brasiliana (Gastropoda, Opisthobranchia).

    Science.gov (United States)

    Kerchove, C M; Markus, R P; Freitas, J C; Costa-Lotufo, L V

    2002-04-01

    Trimethylsulfonium, a compound present in the midgut gland of the sea hare Aplysia brasiliana, negatively modulates vagal response, indicating a probable ability to inhibit cholinergic responses. In the present study, the pharmacological profile of trimethylsulfonium was characterized on muscarinic and nicotinic acetylcholine receptors. In rat jejunum the contractile response induced by trimethylsulfonium (pD2 = 2.46 +/- 0.12 and maximal response = 2.14 +/- 0.32 g) was not antagonized competitively by atropine. The maximal response (Emax) to trimethylsulfonium was diminished in the presence of increasing doses of atropine (P<0.05), suggesting that trimethylsulfonium-induced contraction was not related to muscarinic stimulation, but might be caused by acetylcholine release due to presynaptic stimulation. Trimethylsulfonium displaced [3H]-quinuclidinyl benzilate from rat cortex membranes with a low affinity (Ki = 0.5 mM). Furthermore, it caused contraction of frog rectus abdominis muscles (pD2 = 2.70 +/- 0.06 and Emax = 4.16 +/- 0.9 g), which was competitively antagonized by d-tubocurarine (1, 3 or 10 microM) with a pA2 of 5.79, suggesting a positive interaction with nicotinic receptors. In fact, trimethylsulfonium displaced [3H]-nicotine from rat diaphragm muscle membranes with a Ki of 27.1 microM. These results suggest that trimethylsulfonium acts as an agonist on nicotinic receptors, and thus contracts frog skeletal rectus abdominis muscle and rat jejunum smooth muscle via stimulation of postjunctional and neuronal prejunctional nicotinic cholinoreceptors, respectively. PMID:11960200

  8. A NEW SPECIES OF DIAPHANA FROM BATHYAL DEPTHS IN THE WEDDELL SEA, ANTARCTICA AND FIRST RECORD OF DIAPHANA INFLATA (STREBEL, 1908) IN THE HIGH ANTARCTIC (GASTROPODA: OPISTHOBRANCHIA).

    Science.gov (United States)

    Linse, KATRIN; SchiØtte, TOM

    2002-05-01

    Diaphana haini n.sp. is described from Antarctica. With a depth range from about 400 to 2100 m, D. haini is the second Antarctic species of this genus to extend into the deep sea, the other being D. inflata (Strebel, 1908). Phylogenetic analysis has allowed D. haini to be incorporated within Schiøtte's (1998) cladogram for this genus and, thereby clarify its historical zoogeography. A record of D. inflata from the Weddell Sea extends its known distribution range. The recorded geographic distribution now ranges from South Georgia to the Antarctic continent, and the depth range is extended considerably, from 252-310 m to 1645 m. PMID:12011240

  9. The functional anatomy of the mantle complex and columellar muscle of tectibranch molluscs (Gastropoda: Opisthobranchia), and its bearing on the evolution of opisthobranch organization.

    Science.gov (United States)

    Brace, R C

    1977-02-15

    An account is given of the anatomy of a series of opisthobranch molluscs principally to assess the change in importance and functioning of the mantle cavity and columellar muscle throughout the transition from prosobranch to opisthobranch organization. Intermediate steps are represented by living tectibranchs, of which Philine and Scaphander are investigated in detail, Acteon, Bulla, Haminoea, Akera, Aglaja and Gastropteron more briefly. Though an opisthobranch, Acteon has an organization typical of a monotocardian prosobranch; the remainder show trends affecting the shell and visceral mass, mantle cavity and head-foot, which resulted finally in the production of nudibranch types. It is confirmed that the adaptations exhibited by primitive tectibranchs relate to the assumption of a burrowing mode of life. Initial changes were the reduction of the nuchal area and sealing of the mantle cavity anteriorly so that it opened on the right, where it became restricted, the first perhaps prompting the sealing. A broadening and an anterior elongation of the head-foot produced a wedge to facilitate burrowing. Change in disposition of the mantle edge, incurred by differential growth, produced an involute shell with a large body whorl, alignment changing from erect to horizontal. The resultant streamlining eased infaunal progression; no vertical insinking of the viscera was involved. Subsequently the shell became reduced and finally lost. A section of the mantle edge enlarged to produce a posterior mantle lobe upon which sit both the shell and viscera, and which later became redundant as posterior elongation of the head-foot produced a slug-like form, the viscera being incorporated within the head-foot. As the nuchal area became reduced, mechanical needs prompted alteration to both the form and attachment of the columellar muscle. In Acteon the muscle is like that of a prosobranch, but the proximal region has broadened, a change of proportion required by primitive tectibranchs in order to support the floor of the mantle cavity formed from the section of mantle skirt which in prosobranchs lies on the right. This was followed by reduction and re-alignment of the entire muscle along an anteroposterior axis as emphasis changed from the muscle effecting retraction into a shell to producing contorsions of the head-foot. The shell, similarly reduced, instead of providing anchorage, became itself anchored by additional anterior and posterior attachment zones with, in more advanced forms, dorsoventral muscles of the body wall rather than longitudinal muscles fastening to the former. Importance was placed on the mutual stabilization of constituent parts of the posterior body region. Re-alignments of the muscle induced breaking up of the longitudinal muscle sheet of the head-foot to produce muscle tracts, best exhibited in those tectibranchs which swim; they are derived from both the columellar muscle and intrinsic body wall muscles... PMID:15290

  10. Microanatomia e histologia do sistema digestivo de Phyllocaulis soleiformis (Orbigny) (Mollusca, Gastropoda, Veronicellidae): V. Glândula digestiva Microanatomy and histology of the digestive system of Phyllocaulis soleiformis (Orbigny, 1835) (Mollusca, Gastropoda, Veronicellidae): V. Digestive gland

    OpenAIRE

    Ana Maria Leal-Zanchet; José Willibaldo Thomé; Josef Hauser

    1993-01-01

    The digestive gland of Phyllocaulis soleiformis is a compound tubular gland. The secretory tubules are made up of two main cell types: the digestive cells and calcic cells. The digestive cells are the most numerous, usually columnar, and exhibit three different functional stages: absorptive, secretory and excretory. These cells contain two cytoplasmic granules types and, in the excretory stage, most of the cell is occupied by a large vacuole. The calcic cells occursingly or frequently in grou...

  11. La Familia Trochidae (Mollusca: Gastropoda en el norte de Chile: consideraciones ecológicas y taxonómicas The trochidae family (Mollusca : Gastropoda in northern Chile: taxonomic and ecological considerations

    Directory of Open Access Journals (Sweden)

    DAVID VELIZ

    2000-12-01

    Full Text Available Este estudio describe la diversidad, y la distribución latitudinal y batimétrica de los caracoles de la Familia Trochidae en el norte de Chile, mediante muestreos intermareales y submareales someros, realizados entre 1996 y 1999 entre Arica (18º S y Los Vilos (31º S, y de muestras de profundidad provenientes de la pesca de arrastre del camarón nylon, Heterocarpus reedi. En el norte de Chile, la Familia Trochidae está representada por cuatro géneros: Tegula y Diloma de distribución intermareal y submareal somero hasta los 20 m de profundidad, y Bathybembix y Calliostoma presentes en profundidades superiores a los 200 m. El género Tegula tiene seis especies (T. quadricostata, T. luctuosa, T. ignota, T. atra, T. tridentata y T. euryomphala distribuídas en sustratos rocosos intermareales y submarales someros. El género Diloma está representado por una especie, D. nigerrima, de distribución intermareal hasta pocos metros de profundidad. El género Calliostoma tiene dos especies C. chilena y C. delli, las que se distribuyen entre 200 y 750 m de profundidad. Finalmente, el género Bathybembix está representado por B. humboldti y B. macdonaldi distribuídas entre 200 y 1480 m de profundidad. Esta segregación batimétrica parece estar relacionada a las estrategias alimentarias de cada uno de los géneros de la familia Trochidae. Diloma y Tegula son herbívoros, las especies del género Bathybembix son alimentadoras de depósito y las de Calliostoma son carnívorasThis study reveals the diversity, and the bathimetric and latitudinal distribution of the snails of the Trochidae family members in northern Chile, throughout the analysis of all Trochidae gastropods entailed in intertidal and subtidal (from the `camarón naylon' fishery samples collected during 1996 and 1999 between Arica (ca 18º S and Los Vilos (ca 31º S. The Trochidae family in northern Chile have four genus: Tegula and Diloma that are distributed on intertidal and shallow subtidal habitats, and Calliostoma and Bathybembix which occurr at dephts greather than 200 m. Tegula have 6 species: T. quadricostata, T. luctuosa, T. ignota, T. atra, T. tridentata, and T. euryomphala are distributed on intertidal and shallow subtidal habitats. Diloma is a monospecific genus, whereas D. nigerrima is an intertidal species. The genus Calliostoma have two species C. chilena and C. delli occurring between 200 and 750 m depth and the Bathybembix with two species, B. Humboldti and B. macdonaldi, distributed between 200 and 1480 m depth. The bathimetric distribution of Trochidae shows a strong correlation with food strategy: Diloma and Tegula are herbivores, while Bathybembix species are deposit feeders and Calliostoma are carnivores

  12. Microanatomia e histologia do sistema digestivo de Phyllocaulis soleiformis (Orbigny (Mollusca, Gastropoda, Veronicellidae: V. Glândula digestiva Microanatomy and histology of the digestive system of Phyllocaulis soleiformis (Orbigny, 1835 (Mollusca, Gastropoda, Veronicellidae: V. Digestive gland

    Directory of Open Access Journals (Sweden)

    Ana Maria Leal-Zanchet

    1993-01-01

    Full Text Available The digestive gland of Phyllocaulis soleiformis is a compound tubular gland. The secretory tubules are made up of two main cell types: the digestive cells and calcic cells. The digestive cells are the most numerous, usually columnar, and exhibit three different functional stages: absorptive, secretory and excretory. These cells contain two cytoplasmic granules types and, in the excretory stage, most of the cell is occupied by a large vacuole. The calcic cells occursingly or frequently in groups of two or three, are triangular shaped and have distinct apical granules, and yet calcic histochemical detected granules. In addition, there is a third cell type, without characteristic cytoplasmic granules and which correspond to the undifferentiated cells. The excretory duets system are represented by anterior and posterior vestibules, which branche to form the duets, that communicate with the secretory tubules. These excretory duets are lined with a simple epithelium of ciliated columnar cells, followed by a layer of connective tissue with circular and longitudinal muscular fibers. Subepithelial mucous cells are present only in the vestibules.

  13. 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.

  14. Registro de cópula cruzada e concomitante em Phyllocaulis boraceiensis Thomé (Mollusca, Gastropoda, Veronicellidae Record of the concomitant cross copulation by Phyllocaulis boraceiensis Thomé (Mollusca, Gastropoda, Veronicellidae

    Directory of Open Access Journals (Sweden)

    José Willibaldo Thomé

    1999-01-01

    Full Text Available Two specimens of Phyllocaulis boraceiensis were found in concomitant cross copulation on 19.VII.1997. Each was in the "U"-shape position. Both specimens were the same age. One was 100 mm. long and weighed 14.53 g.; the other was 129 mm long and weighed 16.08 g. Thirty-one days later the largest one laid 11 eggs; all hatched 64 days later. The other died in October, 1997 without laying.

  15. Anatomia e microanatomia do sistema reprodutor de Rectartemon (Rectartemon depressus (Heynemann (Mollusca, Gastropoda, Streptaxidae: complexo fálico Anatomy and microanatomy of the reproductive system of Rectartemon (Rectartemon depressus (Heynemann (Mollusca, Gastropoda, Streptaxidae: the phallus complex

    Directory of Open Access Journals (Sweden)

    Mônica Picoral

    1998-01-01

    Full Text Available It is described the anatomy and microanatomy of the phallus complex of Rectartemon depressus (Heynemann, 1868. The complex is composed by a phallus, a diverticle of the phallus and an epiphallus, where the deferens duct is thrown in: the retractor muscle is splitted in two parts, inserted into the region of the epiphallus through a smaller branch, and at the extremity of the diverticle, through a longer and thiner branch. The lumen of the phallus, epiphallus and diverticle have corrugations and thorns. On the phallus the thorns are arranged in a protuberance and disposed alternately in rows, ali with an aculeus form and with a chestnut collor point and a yellow basis.

  16. Investigation of the Diversity of Mollusca and Evaluation of Water Quality in Hengyang Reach of Xiangjiang River%湘江衡阳段软体动物多样性调查和水质生物学评价

    Institute of Scientific and Technical Information of China (English)

    刘俊; 吴彦琼; 李静; 胡劲松; 李鹏; 刘运莲

    2011-01-01

    The species and diversity and faunal and distribution of molluscas in Hengyang reach of Xiangjiang River were studied after many years of dayuandu hydropower station built; and in virtue of diversity indexes of molluscas, water quality were evaluated. The result of the research showed that there were 45 species of mollusca in Hengyang reaches of Xiang River, which belong to 2 classes and 9 families and 18 genera. 30 species belonging to 11 genera in 6 families of Gastropoda were found, 15 specieses belonging to 7 genera in 3 families of Bivalvia were found. The mollusca was in Oriental realm. 26 species were endemic species in China, and Mekonia hunanensis was in endangered status (It has been listed in China Species Red List as an extinct species). Shannon index was used to evaluate water quality of Hengyang reaches of Xiang River. The result showed that the water quality in Dongzhou ialand and Hengshan county town belonged to clean water, the other 8 sampling sites water had been polluted slightly.%对衡山大源渡电站蓄水多年后的湘江衡阳段软体动物的种类组成、区系分布以及多样性进行了调查,并用生物多样性指数对湘江衡阳段水质进行了评价.调查结果表明,湘江衡阳段计有软体动物45种,分别隶属于2纲9科18属,其中腹足纲6科11属30种,双壳纲3科7属15种,其区系成分主要为东洋界类型;其中26种为中国特有种,且湖南湄公螺为濒危物种(被定为灭绝的物种).用软体动物的Shannon-Wiener多样性指数(H')对湘江衡阳段进行水质生物学评价,研究结果表明,湘江衡阳段的水质除东洲岛和衡山县城为清洁水外,其余8个采样点的水质均受到了轻度污染.

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

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    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.

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

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    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.

  19. Actividad molusquicida in vitro de Momordica charantia L. (¨Cundeamor¨ contra Fossaria cubensis (Mollusca: Gastropoda: Lymnaeidae.

    Directory of Open Access Journals (Sweden)

    Diéguez Fernández, L

    2012-05-01

    Full Text Available RESUMENObjetivo: determinar las perspectivas del uso del jugo vegetal extraído de Momordica charantia L. (Cundeamor, en el control de Fossaria cubensis (Pfeiffer, 1839 principal hospedero de Fasciola hepatica en Cuba.ABSTRACTTo determine the perspectives the use of the juice extracted from the Momordica charantia L.

  20. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

    Science.gov (United States)

    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies.

  1. 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 (68test guidelines for invertebrates. The inter-laboratory reproducibility coefficient of variation (CV) for the Cd LC50-56d values was 8.19%. The inter-laboratory comparison of fecundity within the controls gave a CV of 29.12%, while exposure to Cd gave a CV of 25.49% based on the EC50-56d values. The OECD has acknowledged the success of this prevalidation exercise and a validation ring-test involving 14 laboratories in Europe, North- and South-America is currently being implemented using four chemicals (Cd, prochloraz, trenbolone and tributyltin).

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

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    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.

  3. Polycyclic aromatic hydrocarbons in Haliotis tuberculata (Linnaeus, 1758) (Mollusca, Gastropoda): Considerations on food safety and source investigation.

    Science.gov (United States)

    Conte, Francesca; Copat, Chiara; Longo, Sabrina; Conti, Gea Oliveri; Grasso, Alfina; Arena, Giovanni; Dimartino, Angela; Brundo, Maria Violetta; Ferrante, Margherita

    2016-08-01

    Polycyclic aromatic hydrocarbons were analyzed in wild specimens of Haliotis tuberculata from three sites of the Sothern Ionian Sea. The species Ht is commonly found at these sites and has significant commercial value. Main results revealed mean values of benzo(a)pyrene higher than the threshold set by Regulation No. 835/2011/EU in all sampling sites and the sum of selected PAHs, expressed as ΣPAH4 by EC Regulation, were below the limit set by the same Regulation in ME and VSG. We found generally higher concentrations than literature finding, especially for low molecular weight PAHs, and results of diagnostic ratios highlighted both pyrolytic and petrogenic sources. The potential human health risks due consumption of Ht by local inhabitants have been assessed by exposure daily intake (EDI), target hazard quotient (THQ) and lifetime cancer risk (CR). EDI values were below the intake range reviewed by EFSA for each class of contaminant. BaP daily intake was below the value of 10 ng/Kg/day, suggested by JFCFA, and CRBaP was slightly higher than the acceptable risk level (ARL) of 1×10(-5). Conversely, target hazard quotient (THQ) resulted always below 1, thus the risk to develop chronic systemic effects due naphthalene, acenaphthene, fluorene, anthracene, fluoranthene and pyrene was low. PMID:27235950

  4. The marine Mollusca of the Kendeng Beds (East Java) Gastropoda Part V (Families Muricidae — Volemidae inclusive)

    NARCIS (Netherlands)

    Regteren Altena, van C.O.

    1950-01-01

    Part IV of this monograph was published in volume 12 of this Journal, pp. 89—120, 1942. Since 1941 the author can devote only a small part of his time to these investigations. This fact, and the shortness of paper available for scientific publications, made him decide to alter the way of publication

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

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    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.

  6. 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. PMID:24099753

  7. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

    Science.gov (United States)

    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies. PMID:25259848

  8. Standardization of a Patella spp. (Mollusca, Gastropoda) embryo-larval bioassay and advantages of its use in marine ecotoxicology.

    Science.gov (United States)

    Pérez, Sara; Fernández, Nuria; Ribeiro, Pedro A

    2016-05-01

    The use of three limpet species, Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 and Patella ulyssiponensis Gmelin, 1791 as model organisms in marine ecotoxicology has been evaluated. Initial laboratory experiments were aimed to standardize a biological test with embryos and larvae of Patella spp, establishing the percentage of normal trochophore larvae as endpoint. Before conducting in vitro fertilization, oocytes must be maturated artificially by incubation in an alkaline solution; therefore, alkalinizing agent, pH and time of eggs alkalinization were evaluated. Moreover, time of sperm activation, optimum sperm and oocytes concentration during fertilization, gamete contact time, use of stirring during the fertilization, egg concentration and incubation temperature were examined. Minimum sample size per treatment was also estimated. Exposure of oocytes for 10min to FSW alkalinized with NH4OH at pH 9.0, the use of undiluted sperm pre-activated during 45min and a concentration of 200 oocytesmL(-1), a gamete-contact time of 180min and egg incubation at 18°C during 24h at a concentration of 80 eggsmL(-1) were the conditions allowing maximal embryo-larval development success. With an error of 0.05, a sampling size ≥320 allows a 95% confidence in the estimate. This Patella spp. acute bioassay fulfills a number of important a priori requirements to be used in ecotoxicological studies. Nevertheless, in vitro fertilization requires considerable handling, which may lead to failure in fecundation. Such difficulties are also addressed, in order to facilitate the routine use of this protocol by other laboratories.

  9. Actividad molusquicida in vitro de Momordica charantia L. (¨Cundeamor¨) contra Fossaria cubensis (Mollusca: Gastropoda: Lymnaeidae).

    OpenAIRE

    Diéguez Fernández, L; Piña Pérez, M; Abreu Guirado, O; Vásquez Capote, R; Rodríguez de la Vega, R

    2012-01-01

    RESUMENObjetivo: determinar las perspectivas del uso del jugo vegetal extraído de Momordica charantia L. (Cundeamor), en el control de Fossaria cubensis (Pfeiffer, 1839) principal hospedero de Fasciola hepatica en Cuba.ABSTRACTTo determine the perspectives the use of the juice extracted from the Momordica charantia L.

  10. Histologia da glândula de albúmen de Pomacea canaliculata (Lamarck, 1822 (Mollusca, Gastropoda, Pilidae

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    Eliane de Fátima Marques de Mesquita

    1990-01-01

    Full Text Available In this paper the authors give a histological analysis of the albumen gland of mature and immature females of Pomacea canaliculata (Lamarck, 1822. In the immaturity, tthe gland doesn't show any secretory activity, although in the maturity this activity is indicated by the presence of a homogeneous and eosinophilic material in its lumen. We could notice in the capsule gland of matures females a calcareous element is present as a granular and basophilic deposit. The albumen gland is envolved by a thin conjunctive layer that can be seen in van Gieson's coloured preparations.

  11. Annotated type catalogue of Bothriembryon (Mollusca, Gastropoda, Orthalicoidea) in Australian museums, with a compilation of types in other museums.

    Science.gov (United States)

    Breure, Abraham S H; Whisson, Corey S

    2012-01-01

    Type material of 41 Australian Bothriembryon taxa present in Australian museums is critically listed, indicating systematic issues that need to be resolved in further studies. Information on additional type material of 22 taxa in non-Australian museums is compiled. The seven fossil taxa known so far are included in this catalogue. Based on the current systematic position, 38 species are treated in this paper. Bothriembryon jacksoni Iredale, 1939, Bothriembryon notatus Iredale, 1939, Bothriembryon praecelsus Iredale, 1939 and Bothriembryon serpentinus Iredale, 1939 are elevated to species level. Bothriembryon gratwicki (Cox, 1899) is listed as status to be determined.

  12. On Trichia alpicola (Eder, 1921) from Switzerland (Mollusca: Gastropoda Pulmonata: Hygromiidae) and the spiral sculpture on its shell

    NARCIS (Netherlands)

    Gittenberger, E.; Neuteboom, W.H.

    1991-01-01

    The nominal taxon Fruticicola villosa var. alpicola Eder, 1921, is provisionally considered a separate Trichia species next to T. villosa. The hairs and the spiral sculpture on the shells of both species are illustrated.

  13. On the distribution of the genus Xerocerastus Kobelt & Von Möllendorff, 1902 (Mollusca, Gastropoda Pulmonata, Subulinidae)

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1964-01-01

    Opgedragen aan Prof. Dr. H. Boschma ter gelegenheid van zijn 70ste verjaardag. The subfamily Rumininae of the pulmonate gastropod family Subulinidae is represented in Southern Africa by the endemic genus Xerocerastus Kobelt & von Möllendorff, 1902. Xerocerastus has been divided into three subgenera,

  14. Taxonomic study on the family Mitridae (Mollusca: Gastropoda: Neogastropoda) from the China's seas. Subfamilies: Imbricariinae and Cylindromitrinae

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas. Of which, one genus and six species are recorded for the first time from China' s seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla)carnicolor, Ziba duplilirata, Z. insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.

  15. 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...

  16. Genetic structure of Onchidium "struma" (Mollusca: Gastropoda: Eupulmonata) from the coastal area of China based on mtCO I.

    Science.gov (United States)

    Zhou, Na; Shen, Heding; Chen, Cheng; Sun, Bianna; Zheng, Pei; Wang, Chengnuan

    2016-01-01

    The genetic diversity and population genetic structure of Onchidium "struma" were investigated using mitochondrial cytochrome c oxidase subunit I (CO I) gene sequences. A total of 240 individuals representing 10 collection sites from across a large portion of its known range were included in the analysis. Overall, 42 haplotypes were defined and 97 polymorphic sites were observed. The O. "struma" populations had high haplotype diversity (0.9280) and nucleotide diversity (0.0404). We inferred that the early maturity and extensive survival habitat led to high genetic diversity of O. "struma" populations in China. Bayesian analysis and SAMOVA analysis showed significant genetic differentiation among populations and all populations were divided into two groups, (HK and HN) versus (GY, DF, CX, CN, ND and XM). The Mantel test revealed no significant correlation between geographic distance and genetic distance (r = 0.251; p = 0.058). Restricted gene flow caused by a shorter term pelagic veliger stage and limited dispersal potential were inferred to result in genetic differentiation among populations based on nested analysis. HK population might be an invasive species by artificial transplantation. PMID:25103423

  17. Aspectos histológicos das gônadas hermafroditas de Biomphalaria glabrata e Bradybaena similaris (Mollusca, Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Rinaldo Florêncio da Silva

    2009-01-01

    Full Text Available Biomphalaria glabrata (Say, 1818 é um gastrópode pulmonado de água doce que desperta grande interesse médico e veterinário. Bradybaena similaris (Férussac, 1821 é um gastrópode pulmonado terrestre considerado uma praga agrícola de plantações de hortaliças. Ambas as espécies são hospedeiras intermediárias de helmintos. Esses moluscos possuem uma gônada hermafrodita produtora de óvulos e espermatozóides de forma simultânea. Neste estudo foram avaliados aspectos histomorfológicos das gônadas hermafroditas de B. glabrata e B. similaris. A gônada de B. similaris encontra-se subdividida em lobos com glândulas em seu interior, o que não foi observado em B. glabrata. Além disso, em B. similaris as células germinativas estão acumuladas em determinados pontos e com a presença de um ovócito em cada folículo da gônada; não obstante, em B. glabrata as células germinativas encontraram-se justapostas e com mais de um ovócito em cada folículo.Biomphalaria glabrata (Say, 1818 is a freshwater pulmonate gastropod that represents great medical importance. Bradybaena similaris (Férussac, 1821 is a terrestrial pulmonate gastropod and an important plague to the different plant cultures with economic interest. Both species are intermediate hosts of helminths. These molluscs have hermaphrodites gonads producing eggs and sperm. Here, we examined histoformological aspects of hermaphrodites gonads of both B. glabrata and B. similaris. The gonad of B. similaris is subdivided into lobes and presence of glands in its interior, which was not observed in B. glabrata. Moreover, in B. similaris the germ cells are accumulated in some areas, and has one oocyte in each follicle in the gonad; however, in B. glabrata the germ cells are juxtaposed and more than one oocyte in each follicle.

  18. 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 (e

  19. Discrete potential waves in the photoreceptors of a gastropod mollusc, Hermissenda crassicornis.

    Science.gov (United States)

    Takeda, T

    1982-01-01

    Intracellular recording of dark adapted photoreceptors of Hermissenda crassicornis (Opisthobranchia, Gastropoda, Mollusca) revealed the occurrence of depolarizing waves even after blockade of synaptic transmission and postsynaptic potentials by application of low Ca2+ and high Mg2+ solution. Dim illumination increased the frequency of depolarizing waves. These observations show that Hermissenda photoreceptors have discrete waves which have been demonstrated mainly in arthropod photoreceptors. An histogram of intervals between successive discrete waves under continuous dim illumination was exponential, which is characteristic of a Poisson process. Frequency of discrete waves increased linearly depending on numbers of incident photons to the eye. Comparison of probabilities of eliciting a response to brief dim flashes of various intensities to theoretical Poisson sum curves, together with statistical analysis, indicate that the absorption of single photon is sufficient to evoke a discrete wave. PMID:7101766

  20. 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.

  1. New Mediterranean Biodiversity Records (June 2012

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    A. NICOLAIDOU

    2012-12-01

    Full Text Available The present work reports on the extended distribution of nineteen species in the Mediterranean. These are: Upeneus pori(Fish:Turkey, Bursatella leachii (Mollusca, Opisthobranchia: eastern coast of Spain, Sparisoma cretense (Fish: Ionian coastof Greece, Pseudobryopsis myura (Chlorophyta: Turkey, Aplysia dactylomela (Mollusca, Opisthobranchia: Karpathos island,and Kyklades Archipelago, Greece, Asparagopsis armata and Botryocladia madagascariensis (Rhodophyta: South Peloponnesos,Greece, Oxynotus centrina (Fish: Greece, Caulerpa racemosa var. cylindracea (Chlorophyta , Stypopodium schimperi(Phaeophyta Siganus luridus and Stephanolepis diaspros (Fish Percnon gibbesi (Decapoda, Brachyura (Kyklades Archipelago,Greece, Cerithium scabridum (Mollusca, Prosobranchia: Anavissos: Greece and Cerithium renovatum (Mollusca, Prosobranchia:N. Κriti, Cassiopea andromeda (Scyphomedusa: Rhodos Island, Greece, Abra tenuis (Mollusca Bivalvia: VouliagmeniLake, Greece Lagocephalus lagocephalus (Fish: Calabrian coast, Italy and Plocamopherus ocellatus (Mollusca, Opisthobranchia:İskenderun Bay, Turkey.

  2. The complete mitochondrial genome of Scutopus ventrolineatus (Mollusca: Chaetodermomorpha) supports the Aculifera hypothesis

    OpenAIRE

    Osca, David; Irisarri, Iker; Todt, Christiane; Grande, Cristina; Zardoya, Rafael

    2014-01-01

    Background With more than 100000 living species, mollusks are the second most diverse metazoan phylum. The current taxonomic classification of mollusks recognizes eight classes (Neomeniomorpha, Chaetodermomorpha, Polyplacophora, Monoplacophora, Cephalopoda, Gastropoda, Bivalvia, and Scaphopoda) that exhibit very distinct body plans. In the past, phylogenetic relationships among mollusk classes have been contentious due to the lack of indisputable morphological synapomorphies. Fortunately, rec...

  3. Naididae (Annelida, Oligochaeta associated with Pomacea bridgesii (Reeve (Gastropoda, Ampullaridae Naididae (Annelida: Oligochaeta associados a Pomacea bridgesii (Reeve (Gastropoda, Ampullaridae

    Directory of Open Access Journals (Sweden)

    Guilherme R. Gorni

    2006-12-01

    Full Text Available The family Amplullaridae belongs to this class Gastropoda and is made up of freshwater organisms with a wide geographical distribution in tropical regions. Oligochaeta worms can be found in association with snails of this family, inhabiting the umbilicus of their shells. Due to the lack of information on the ecology of these worms, this work focused on investigating which kind of Oligochaeta species associate with the mollusk Pomacea bridgesii (Reeve, 1856. Samples were collected during winter and spring 2003 and summer 2004. From a total of 209 snails collected, the presence of Oligochaeta worms was observed in only 58 of them (27.75%. In these infected snails, 89 Oligochaeta worms were found, all belonging to the family Naididae. The species Haemonais waldvogeli Bretscher, 1900, Dero (Dero nivea Aiyer, 1929 and Dero (Dero sawayai Marcus, 1943 were the most abundant (43.68%, 12.32% and 10.08%, respectively. Haemonais waldvogeli was found in all of the seasons studied, what demonstrates its affinity for this kind of substrate. The results indicate that several Naididae species find in the umbilicus of these snails's shells (which contains fine detritus a favorable habitat for establishing themselves.A família Ampullaridae, pertencente à classe Gastropoda, é caracterizada por organismos de água doce com ampla distribuição na região tropical. Vermes Oligochaeta associados a esses caracóis podem ser encontrados habitando o umbílico de suas conchas. Devido à carência de informação sobre a ecologia desses vermes, o presente trabalho centrou-se em um levantamento de espécies de Oligochaeta associadas ao molusco Pomacea bridgesii (Reeve, 1856. Em amostragens realizadas no inverno e na primavera de 2003 e no verão de 2004, foram observados 209 caracóis, sendo que somente em 58 deles foi detectada a presença de vermes Oligochaeta, correspondendo a uma incidência de 27,75%. Foram encontrados, no total, 89 oligoquetos, todos da fam

  4. Bait formulations of molluscicides and their effects on biochemical changes in the ovotestis of snail Lymnaea acuminata (Mollusca; Gastropoda:Lymnaeidae)

    OpenAIRE

    Pradeep Kumar; Vinay Kumar Singh; D K Singh

    2011-01-01

    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...

  5. On a collection of Peruvian Neniinae (Mollusca: Gastropoda: Clausiliidae), with a check-list and a provisional key to all the Peruvian species known

    NARCIS (Netherlands)

    Loosjes, F.E.; Loosjes-van Bemmel, A.C.W.

    1984-01-01

    An annotated list is given of all Neniinae collected in 1975 by Dr. A. S. H. Breure in Peru. The localities that have been visited are also listed, together with the Neniinae collected there. Pseudogracilinenia gen. nov. is described for P. huallagana (Pilsbry, 1949) (type-species) and P.jolyi (O. B

  6. 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.

  7. 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

    2016-10-01

    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.

  8. 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.

  9. A new species of Tambja (Mollusca, Gastropoda, Nudibranchia) from the Mediterranean Sea: description of the first species of the genus from the Balearic Islands and Malta

    Science.gov (United States)

    Domínguez, M.; Pola, M.; Ramón, M.

    2015-06-01

    A new species of polycerid nudibranchs of the genus Tambja is described from Mallorca Island (Spain) and Malta. So far, only two species of Tambja had been recorded in the Mediterranean Sea with a distribution limited to southern Spain. With Tambja mediterranea sp. nov., the distribution of the genus in the Mediterranean Sea is extended, and the new species represents the first occurrence of Tambja at the Balearic Islands and Malta. Externally, the new species is mainly characterized by having ground orange-red colour, dorsum covered with rounded whitish tubercles, rhinophores red with whitish tips and three gill branches with orange-reddish rachis and whitish branches. In the present paper, external and internal features of T. mediterranea are described and compared with other species of the genus, especially with its most similar species, T. limaciformis. Additionally, phylogenetic analyses (Bayesian and maximum likelihood) based on mitochondrial sequences (COI) show that T. mediterranea sp. nov. is sister to T. divae and that both species cluster together with T. limaciformis and T. amakusana with the maximum support.

  10. 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.

  11. Registro de Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda no Brasil: caramujo hospedeiro intermediário da angiostrongilíase

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    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.

  12. Evaluation of the mitochondrial system in the gonad-digestive gland complex of Biomphalaria glabrata (Mollusca, Gastropoda) after infection by Echinostoma paraensei (Trematoda, Echinostomatidae).

    Science.gov (United States)

    Tunholi, Victor Menezes; Tunholi-Alves, Vinícius Menezes; Santos, Anderson Teixeira; Garcia, Juberlan da Silva; Maldonado, Arnaldo; da-Silva, Wagner Seixas; Rodrigues, Maria de Lurdes de Azevedo; Pinheiro, Jairo

    2016-05-01

    The effect of infection by Echinostoma paraensei on the mitochondrial physiology of Biomphalaria glabrata was investigated after exposure to 50 miracidia. The snails were dissected one, two, three and four weeks after infection for collection and mechanical permeabilization of the gonad-digestive gland (DGG) complex. The results obtained indicate that prepatent infection by this echinostomatid fluke significantly suppresses the phosphorylation state (respiratory state 3) and basal oxygen consumption of B. glabrata, demonstrating that the infection reduces the ability of the intermediate host to carry out aerobic oxidative reactions. Additionally, relevant variations related to the uncoupled mitochondrial (state 3u) of B. glabrata infected by E. paraensei were observed. Four weeks after exposure, a significant reduction in mitochondrial oxygen consumption after addition of ADP (3.68±0.26pmol O2/mg proteins) was observed in the infected snails in comparison with the respective control group (5.14±0.25). In the uncoupled state, the infected snails consumed about 62% less oxygen than the infected snails (7.87±0.84pmol O2/mg proteins) in the same period. These results demonstrate a reduction in oxidative decarboxylation rate of the tricarboxylic acid cycle and faster anaerobic degradation of carbohydrates in the infected snails. The possible mechanisms that explain this new metabolic condition in the infected organisms are discussed. PMID:27079167

  13. Effect of pollution on some freshwater species. I. histochemical and biochemical features of lead pollution on some organs of Viviparus viviparus L. (Mollusca Gastropoda)

    Energy Technology Data Exchange (ETDEWEB)

    Benedetti, I.; Benedetti, L.; Bolognani, L.; Bolognani Fantin, A.M.; Marini, M.; Ottaviani, E.

    1982-01-01

    Experimental lead pollution was studied in some organs (foot, mantle and digestive gland) of Viviparus viviparus L. The amount of lead contained after 48h, 96 h and one week of pollution were established using an atomic absorption spectrophotometer. On the basis of physicochemical determination, it turns out that lead is mainly concentrated in the mantle. The biochemical tests (cholesterol, sulpholipids and phospholipids) were aimed at evaluating the lipids involved in the membranes. The histochemical research was carried out chiefly to evaluate the modifications of polysaccharides and proteins. Some hydrolytic enzymes (Na+ and K+ dependent ATPase) and some ooreductive enzymes (NADH+ and NADPH+ dependent diaphorases, D-lactate dehydrogenase, succinate dehydrogenase and glucose-6-P-dehydrogenase) were also tested. The digestive gland is the most severely damaged organ as proved by histomorphological and biochemical analyses.

  14. Phylogenetic analysis of euthyneuran gastropods from sea to land mainly based on comparative mitogenomic of four species of Onchidiidae (Mollusca: Gastropoda: Pulmonata).

    Science.gov (United States)

    Sun, Bian Na; Wei, Luan Luan; Shen, He Ding; Wu, Hong Xi; Wang, Dong Feng

    2016-09-01

    We generated complete mitochondrial genome sequences data for 4 genera (Onchidium, Platevindex, Paraoncidium and Peronia) in Onchidiidae to construct a phylogenetic tree in conjunction with other 9 existing data among gastropods. The topology showed that the taxa clustered into two main groups of four species, one of which included Onchidium struma and the Platevindex mortoni, the other Paraoncidium reevesii and Peronia verruculata. The process in Pulmonata from sea to land in accordance with the evolution of respiratory organs from branchial gills to pulmonary cavity has been shown. This will also constitute a framework for phylogeny evolution analysis, systematic classfication of Onchidiidae and other euthyneurans (pulmonates and opisthobranchs). PMID:25648917

  15. Current knowledge on population studies on five continental molluscs (Mollusca, Gastropoda et Bivalvia of Santa Catarina State (SC, Central Southern Brazil region

    Directory of Open Access Journals (Sweden)

    A. Ignacio Agudo-Padrón

    2011-03-01

    Full Text Available Although still very scarce, available knowledge on population studies on continental (land and freshwatermolluscs in the territory of Santa Catarina State is shortly analyzed and discussed. Based on the IUCN“Restricted Distribution” criterion, a total of 54 nominal species, including 31 terrestrial gastropods, 15freshwater gastropods and 8 limnic bivalves, were considered strong candidates as threatened taxa. Out of allthese endangered species, only 5 limnic forms (2 gastropods and 3 bivalves were previously analysed, in someway, at population level.

  16. On the doubtful records of Alvania platycephala, Alvania pagodula and Alvania didyma, with the description of two new rissoid species (Mollusca; Gastropoda: Rissoidae)

    NARCIS (Netherlands)

    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.

  17. 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.

  18. 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.

  19. 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.

  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...

  1. Effect of pollution on some freshwater species. II. Bioaccumulation and toxic effects of experimental lead pollution on the ganglia in Viviparus ater (Mollusca, Gastropoda)

    Energy Technology Data Exchange (ETDEWEB)

    Bolognani Fantin, A.M.; Franchini, A.; Ottaviani, E.; Benedetti, L.

    1985-01-01

    The effect of lead on ganglia of Viviparus ater were studied by histochemical and histomorphological procedures. The pollution experiment should be considered a short-time static bioassay because of its experimental characteristics. There was considerable accumulation of lead in the ganglia as determined by atomic absorbance (A.A.S.). The cytological damage principally affected the neuronal cell bodies which undergo degenerative processes. The most serious cytopathological changes occurred in the following sequence: nuclear damage leading to pyknosis; nucleolar damage until disappearance; changes in Nissl bodies, at times forming a uniform mass. These cytological disorders led to markedly altered protein synthesis. Nerve fibers and neuroglia did not appear affected by lead exposure, even at higher doses. Membrane enzymes, phosphorylase, NADHDH, NADPHDH and SDH activities were decreased, whereas D-LDH, G-6-PDH, G-6-Pase and MAO activities increased. GDH was unchanged. Changes in polar lipid composition were also observed with an increase of phospholipids and a decrease of sulpholipids and cerebrosides.

  2. Microanatomy and ultrastructure of the excretory system of two pelagic opisthobranch species (Gastropoda: Gymnosomata and Thecosomata).

    Science.gov (United States)

    Fahrner, A; Haszprunar, G

    2000-04-01

    The microanatomy and ultrastructure of the excretory system of Pneumoderma sp. (Gymnosomata) and Creseis virgula Rang, 1828 (Thecosomata) have been investigated by means of semithin serial sections, reconstructions and transmission electron microscopy. The studies revealed a functional metanephridial system consisting of a heart with a single ventricle and auricle in a pericardial cavity and a single kidney in both species. Podocytes in the atrial wall of the pericardial epithelium are the site of ultrafiltration, whereas the flat epithelium of the kidney with numerous basal infoldings and a dense microvillous border on the luminal surface suggests modification of the ultrafiltrate. In Pneumoderma sp., additional loci of ultrafiltration with identical fine structure (meandering slits with diaphragms covered by extracellular matrix) occur in the solitary rhogocytes (pore cells). The presence of podocytes situated on the atrial wall in representatives of two higher opisthobranch taxa contradicts former ideas on the loss of the primary site of ultrafiltration in the ancestors of the Opisthobranchia. PMID:11085207

  3. A honeycomb composite of mollusca shell matrix and calcium alginate.

    Science.gov (United States)

    You, Hua-jian; Li, Jin; Zhou, Chan; Liu, Bin; Zhang, Yao-guang

    2016-03-01

    A honeycomb composite is useful to carry cells for application in bone, cartilage, skin, and soft tissue regenerative therapies. To fabricate a composite, and expand the application of mollusca shells as well as improve preparing methods of calcium alginate in tissue engineering research, Anodonta woodiana shell powder was mixed with sodium alginate at varying mass ratios to obtain a gel mixture. The mixture was frozen and treated with dilute hydrochloric acid to generate a shell matrix/calcium alginate composite. Calcium carbonate served as the control. The composite was transplanted subcutaneously into rats. At 7, 14, 42, and 70 days after transplantation, frozen sections were stained with hematoxylin and eosin, followed by DAPI, β-actin, and collagen type-I immunofluorescence staining, and observed using laser confocal microscopy. The composite featured a honeycomb structure. The control and composite samples displayed significantly different mechanical properties. The water absorption rate of the composite and control group were respectively 205-496% and 417-586%. The composite (mass ratio of 5:5) showed good biological safety over a 70-day period; the subcutaneous structure of the samples was maintained and the degradation rate was lower than that of the control samples. Freezing the gel mixture afforded control over chemical reaction rates. Given these results, the composite is a promising honeycomb scaffold for tissue engineering.

  4. 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.

  5. Morphological Description of a Newly Recorded Strombus luhuanus (Strombidae: Gastropoda from Korea

    Directory of Open Access Journals (Sweden)

    Junhee Lee

    2013-01-01

    Full Text Available The Strombus Linne, 1758 is a genus of marine mollusks belonging to the class Gastropoda, and is distributed in the tropical waters of the world. Typically, the family Strombidae includes five extant genera (Strombus, Lambis, Terebellum, Tibia, and Rimella, all of which are mostly found in tropical waters. Five individuals of Strombus luhuanus Linne, 1758 were collected from Uljin, Gyeongsangbuk-do province for the first time. In this study, we describe details of shell morphology and radula characters of the species with scanning electron microscopy images of the radula. This is a new record of Strombus luhuanus Linne, 1758 from Korean waters.

  6. Anti-ulcer potentials of phylum mollusca (tropical snail) slime

    Institute of Scientific and Technical Information of China (English)

    Nwodo NJ; Okonta J M; Ezugwu CO; Attama AA

    2009-01-01

    Objective:The effectiveness of the slimy substance in snail to regenerate and repair damaged areas on its body/shell lead to this investigation.Methods:The anti-ulcer'property of snail slime extracted from phylum mollusca (tropical snail)from the giant African snail Archachatina marginata (Fam.Arionidae)was investi-gated using histamine,stress and indomethacin-induced ulcers.The solubility profile of extract was investiga-ted in different solvents and at different temperatures.Chemical analysis was carried out to determine the types of constituents present in the slim,while acute toxicity test was carried out to evaluate its profile of toxicity. The effect of the snail slim on gastrointestinal motility was investigated in mice,while the guinea pig ileum was used to study the effect of the extract on contraction produced by acetylcholine and histamine.The snail slime contained copious quantity of protein,with varying amounts of simple sugars,carbohydrates and fats.The slime was not soluble in most common solvents and increases in temperature,did not appear to increase its sol-ubility.Results:The result further indicated that although the snail slime exhibited significant (P <0.05)an-ti-ulcer induced by stress and histamine,it was most potent against ulcer induced by indomethacin.The snail slime potently inhibited gastrointestinal movement in mice in a dose-dependent manner;however,it was not a-ble to inhibit contraction induced by acetylcholine and histamine in guinea pig ileum.Conclusion:The snail mucin possesses potent antiulcer properties without any toxic effect.The mechanism responsible for the anti-ul-cer property may not be postulated with certainty but cytoprotective and anti-spasmodic activities are most likely to be involved.

  7. LARVAS DE DIGENEA EN Melanoides tuberculata (GASTROPODA: THIARIDAE EN MEDELLÍN, COLOMBIA Larval stages of digenea from Melanoides tuberculata (Gastropoda: Thiaridae in Medellín, Colombia

    Directory of Open Access Journals (Sweden)

    DANIELA VERGARA

    Full Text Available Se describen las larvas de digeneos que se obtuvieron en Melanoides tuberculata (Gastropoda: Thiaridae, molusco dulceacuícola del que se colectaron 125 especímenes en el lago del Jardín Botánico Joaquín Antonio Uribe de Medellín. En el laboratorio se individualizaron y se estimuló la emisión cercariana con una fuente luminosa. El 9,6 % de los caracoles emitió cercarias. Los moluscos emisores se sacrificaron para obtener los demás estadios larvarios. Las larvas se montaron al microscopio, se midieron y luego se dibujaron. Los caracteres morfológicos permitieron establecer la presencia de Centrocestus formosanus (Heterophyidae y de dos Philophthalmidae. Uno de estos es primer registro para Colombia. Se confirma la sensibilidad de M. tuberculata a infecciones por digeneos, así como la especificidad de los filoftálmidos por moluscos hospedadores de la superfamilia Cerithioidea.The larvae of two trematodes found in the freshwater mollusk Melanoides tuberculata (Gastropoda: Thiaridae are described. 125 snails from the Medellin’s Botanical Garden Joaquín Antonio Uribe were collected. In the laboratory, each individual was placed alone and stimulated with light in order to have cercaria emission. 9.6% of the snails released cercariae. These were separated in three morphologies. From each one, 15 individuals were measured and drawn. Photographs were taken. Based on their morphological characteritics the presence of Centrocestus formosanus (Heterophyidae was determined. The other two morphologies were classified in the family Philophthalmidae. One of them constitutes the first register for Colombia. The sensibility of M. tuberculata to infections by digeneans, and the specificity of the family Philophthalmidae to mollusk hosts of the superfamily Cerithioidea are confirmed

  8. 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.

  9. What explains the invading success of the aquatic mud snail Potamopyrgus antipodarum (Hydrobiidae, Mollusca)?

    OpenAIRE

    Alonso, A.; Castro-Diez, P.

    2008-01-01

    The spread of non-native species is one of the most harmful and least reversible disturbances in ecosystems. Species have to overcome several filters to become a pest (transport, establishment, spread and impact). Few studies have checked the traits that confer ability to overcome these steps in the same species. The aim of the present study is to review the available information on the life-history and ecological traits of the mud snail, Potamopyrgus antipodarum Gray (Hydrobiidae, Mollusca),...

  10. Systematic notes on the Mesodesmatidae (Mollusca, Bivalvia), and descriptions of a new species and a new subspecies

    NARCIS (Netherlands)

    Rooij-Schuiling, de L.A.

    1972-01-01

    In 1959, Mr. A. Hoogerwerf obtained a number of small Mollusca from the gizzard of a godwit (Limosa spec.) shot near Koerik, West Irian, New Guinea, that eventually came into my hands for identification. Though the specimens clearly belonged to a species of the genus Mesodesma (Mactracea, fam. Mesod

  11. 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.

  12. Parallel evolution of serotonergic neuromodulation underlies independent evolution of rhythmic motor behavior.

    Science.gov (United States)

    Lillvis, Joshua L; Katz, Paul S

    2013-02-01

    Neuromodulation can dynamically alter neuronal and synaptic properties, thereby changing the behavioral output of a neural circuit. It is therefore conceivable that natural selection might act upon neuromodulation as a mechanism for sculpting the behavioral repertoire of a species. Here we report that the presence of neuromodulation is correlated with the production of a behavior that most likely evolved independently in two species: Tritonia diomedea and Pleurobranchaea californica (Mollusca, Gastropoda, Opisthobranchia, Nudipleura). Individuals of both species exhibit escape swimming behaviors consisting of repeated dorsal-ventral whole-body flexions. The central pattern generator (CPG) circuits underlying these behaviors contain homologous identified neurons: DSI and C2 in Tritonia and As and A1 in Pleurobranchaea. Homologs of these neurons also can be found in Hermissenda crassicornis where they are named CPT and C2, respectively. However, members of this species do not exhibit an analogous swimming behavior. In Tritonia and Pleurobranchaea, but not in Hermissenda, the serotonergic DSI homologs modulated the strength of synapses made by C2 homologs. Furthermore, the serotonin receptor antagonist methysergide blocked this neuromodulation and the swimming behavior. Additionally, in Pleurobranchaea, the robustness of swimming correlated with the extent of the synaptic modulation. Finally, injection of serotonin induced the swimming behavior in Tritonia and Pleurobranchaea, but not in Hermissenda. This suggests that the analogous swimming behaviors of Tritonia and Pleurobranchaea share a common dependence on serotonergic neuromodulation. Thus, neuromodulation may provide a mechanism that enables species to acquire analogous behaviors independently using homologous neural circuit components. PMID:23392697

  13. With a little help from DNA barcoding: investigating the diversity of Gastropoda from the Portuguese coast.

    Science.gov (United States)

    Borges, Luísa M S; Hollatz, Claudia; Lobo, Jorge; Cunha, Ana M; Vilela, Ana P; Calado, Gonçalo; Coelho, Rita; Costa, Ana C; Ferreira, Maria S G; Costa, Maria H; Costa, Filipe O

    2016-02-15

    The Gastropoda is one of the best studied classes of marine invertebrates. Yet, most species have been delimited based on morphology only. The application of DNA barcodes has shown to be greatly useful to help delimiting species. Therefore, sequences of the cytochrome c oxidase I gene from 108 specimens of 34 morpho-species were used to investigate the molecular diversity within the gastropods from the Portuguese coast. To the above dataset, we added available COI-5P sequences of taxonomically close species, in a total of 58 morpho-species examined. There was a good match between ours and sequences from independent studies, in public repositories. We found 32 concordant (91.4%) out of the 35 Barcode Index Numbers (BINs) generated from our sequences. The application of a ranking system to the barcodes yield over 70% with top taxonomic congruence, while 14.2% of the species barcodes had insufficient data. In the majority of the cases, there was a good concordance between morphological identification and DNA barcodes. Nonetheless, the discordance between morphological and molecular data is a reminder that even the comparatively well-known European marine gastropods can benefit from being probed using the DNA barcode approach. Discordant cases should be reviewed with more integrative studies.

  14. No evidence for a culturable bacterial tetrodotoxin producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae) and Stylochoplana sp. (Platyhelminthes: Polycladida).

    Science.gov (United States)

    Salvitti, Lauren R; Wood, Susanna A; McNabb, Paul; Cary, Stephen Craig

    2015-02-01

    Tetrodotoxin (TTX) is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia) and Stylochoplana sp. (Platyhelminthes). Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography-mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0), suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely. PMID:25635464

  15. No Evidence for a Culturable Bacterial Tetrodotoxin Producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae and Stylochoplana sp. (Platyhelminthes: Polycladida

    Directory of Open Access Journals (Sweden)

    Lauren R. Salvitti

    2015-01-01

    Full Text Available Tetrodotoxin (TTX is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia and Stylochoplana sp. (Platyhelminthes. Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography—mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0, suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely.

  16. Multiple forms of octopine dehydrogenase in Strombus luhuanus (mollusca, gastropoda, strombidae): genetic basis of polymorphism, properties of the enzymes, and relationship between the octopine dehydrogenase phenotype and the accumulation of anaerobic end products during exercise.

    Science.gov (United States)

    Baldwin, J; England, W R

    1982-10-01

    Octopine dehydrogenase (ODH) is electrophoretically polymorphic in the gastropod mollusk Strombus luhuanus. The frequencies of the six electrophoretic phenotypes in the Heron Island population, together with the molecular weight values of 38,000 obtained for each of the three forms of the enzyme, demonstrate that the monomeric enzyme is encoded by three codominant alleles at a single locus. The purified allozymes are indistinguishable in terms of Km values for substrates, product inhibition by octopine and NAD, pH optima, and substrate inhibition by pyruvate. No statistically significant correlations were found between the ODH phenotype and the maximum activities of ODH or alanopine dehydrogenase, the capacity for anaerobic muscle work, or the accumulation of octopine or strombine/alanopine during exercise. It would appear that the ODH allozymes may be functionally equivalent both in vitro and in vivo. PMID:7181845

  17. 广东海陵岛沿海软体动物的分布%DISTRIBUTION OF CLASS BIVALVIA AND GASTROPODA MOLLUSCA IN THE INSHORE REGIONS OF HAILING ISLAND OF GUANGDONG

    Institute of Scientific and Technical Information of China (English)

    唐以杰; 林炜; 陈明旺; 钟诚; 杜晓捷

    2005-01-01

    对海陵岛沿海软体动物进行了采集调查,共鉴定180种,分属 60科. 其中双壳纲20科86种,占总数47.77%,腹足纲38科92种,占总数51.11%,多板纲1科1种,占总数0.56%,头足纲1科1种,占总数0.56%. 分析表明,其区系特点以南海亚热带-热带种和东海-南海亚热带种为主要成分.

  18. Gastropoda-Bivalvia Fauna And Neogene-Quaternary Stratigraphy of the Southwest of Dardanelles (Çanakkale-NWAnatolia)

    Science.gov (United States)

    Kapan, Sevinç; Kabasakal, Sinem

    2016-04-01

    Gastropoda-Bivalvia Fauna And Neogene-Quaternary Stratigraphy of the Southwest of Dardanelles (Çanakkale-NWAnatolia) Sevinç KAPAN, Sinem KABASAKAL, Çanakkale Onsekiz Mart University, Engineering Faculty, Geological Engineering Department sevinckapan_yesilyurt@hotmail.com In this study, paleontology and stratigraphy of Neogene and Quaternary units around south of the Dardanelles have been examined using Gastropoda and Bivalvia fauna. In the investigation area, the base of the sediments that belongs to Neogene, consist of the volcanics which are formed with basalts, andesites and tuff. Neogene begins unconformity with basal conglomerate which are formed with basalt and tuff gravels. The measurable thickness of the Neogene sediments is approximately 200meters in total. First fossiliferius level which consist of Lymnocardium (Euxinicardium) nobile Sabba has showed similarities with the Pontian (Late Miocene) fauna of the Eastern Paratethys. The existence of Melanopsis and Psidium species indicate that the basin has been brackish water feeding by fresh water in the Early Pliocene. Theodoxus fluviatilis (Linne), Theodoxus (Calvertia) aff. imbricata Brusina, Theodoxus (Calvertia) licherdopoli scriptus (Stefanescu), Viviparus mammatus (Stefanescu), Valvata (Valavata) sulekiana Brusina, Valvata (Cincinna) crusitensis Fontannes, Hydrobia cf grandis Cobalcescu, Hydrobia ventrosa Monfort, Melanopsis (Melanopsis) cf. bergeroni Stefanescu, , Melanopsis (Melanopsis) sandbergeri rumana Tournouer, Melanopsis (Canthidomus) hybostoma anili Taner, Melanopsis (Canthidomus) hybostoma amaradica Fontannes, Melanopsis (Canthidomus) lanceolata Neumayr, Amphimelania fossariformis (Tournouer), Melanoides tuberculata monolithica (Bukowski), Radix (Radix) peregra (Müller), Planorbarius thiollierei (Michaud), Potamida (Potamida) craiovensis craiovensis (Tournouer), Potamida (Potamida) berbestiensis (Fontannes), Unio pristinus davilai Porumbaru, Unio subexquisitus Jatzko, Anadonta zmaji

  19. Utilization of shells of the snail Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda) by the hermit crab Clibanarius vittatus (Bosc, 1802) (Decapoda, Anomura) in the São Vicente Estuary, São Paulo, Brazil Utilización de conchas de caracoles terrestres Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda) por el cangrejo ermitaño Clibanarius vittatus (Bosc, 1802) (Decapoda, Anomura) en el estuario de São Vicente, São Paulo, Brasil

    OpenAIRE

    Bruno S. Sant'Anna; Cilene M. Zangrande; Alvaro L. D. Reigada

    2005-01-01

    Hermit crabs depend on mollusc shells for housing. In this study, an unusual resource is reported for a hermit crab that usually inhabits marine gastropod shells. During a field study conducted from May 2001 to April 2003 in an estuarine area in São Vicente, state of São Paulo, Brazil, 21 individuals of Clibanarius vittatus (Bosc, 1802) were found inhabiting the shells of the terrestrial gastropod Achatina fulica Bowdich, 1822. A. fulica occurs in nearshore grass patches, where occasional con...

  20. The identity of Isocrassina, Laevastarte and Ashtarotha (Mollusca, Bivalvia, Astartidae) and their representatives from beaches and estuaries in The Netherlands and Pliocene strata in Belgium

    NARCIS (Netherlands)

    Pouwer, R.

    2009-01-01

    The identity of the subgenera Isocrassina Chavan, 1950, Laevastarte Hinsch, 1952, and Ashtarotha Dall, 1903, of the genus Astarte Sowerby, 1816 in the family Astartidae (Mollusca, Bivalvia) is discussed. Isocrassina has been widely used for Pliocene species in the North Sea Basin. Here it is demonst

  1. Hard and soft anatomy in two genera of Dondersiidae (Mollusca, Aplacophora, Solenogastres).

    Science.gov (United States)

    Scheltema, Amélie H; Schander, Christoffer; Kocot, Kevin M

    2012-06-01

    Phylogenetic relationships and identifications in the aplacophoran taxon Solenogastres (Neomeniomorpha) are in flux largely because descriptions of hard parts--sclerites, radulae, copulatory spicules--and body shape have often not been adequately illustrated or utilized. With easily recognizable and accessible hard parts, descriptions of Solenogastres are of greater use, not just to solenogaster taxonomists, but also to ecologists, paleontologists, and evolutionary biologists. Phylogenetic studies of Aplacophora, Mollusca, and the Lophotrochozoa as a whole, whether morphological or molecular, would be enhanced. As an example, morphologic characters, both isolated hard parts and internal anatomy, are provided for two genera in the Dondersiidae. Five species are described or redescribed and earlier descriptions corrected and enhanced. Three belong to Dondersia: D. festiva Hubrecht, D. incali (Scheltema), and D. namibiensis n. sp., the latter differentiated unambiguously from D. incali only by sclerites and copulatory spicules. Two species belong to Lyratoherpia: L. carinata Salvini-Plawen and L. californica (Heath). Notes are given for other species in Dondersiidae: L. bracteata Salvini-Plawen, Ichthyomenia ichthyodes (Pruvot), and Heathia porosa (Heath). D. indica Stork is synonymized with D. annulata. A cladistic morphological analysis was conducted to examine the utility of hard parts for reconstructing solenogaster phylogeny. Results indicate monophyly of Dondersia and Lyratoherpia as described here.

  2. A review of the non-bulimulid terrestrial Mollusca from the Region of Atacama, northern Chile

    Science.gov (United States)

    Araya, Juan Francisco; Catalán, Ricardo

    2014-01-01

    Abstract Terrestrial mollusca are sparsely studied in Chile and, for the first time, a formal record of the diversity of land snails in northern Chile is reported. Coastal and desertic areas in the Region of Atacama, in the border of the Atacama desert and the Pacific Ocean, were surveyed with the aim to describe the presence and distribution of this poorly known fauna. Of the fourteen species recorded, the geographic distribution records for nine species are extended, and some taxa are recorded for the first time since their original descriptions. All, except one, of the fourteen terrestrial molluscan species occurring in the area are endemic to Chile; they are all terrestrial species, most of them have a restricted geographic distribution, and none of them is currently protected by law. The results reveal that the region of Atacama has one of the most diverse terrestrial snail biodiversity in Chile, ranking only after the Juan Fernandez Archipelago. Distribution records of all the studied species and a taxonomic key are also provided. PMID:24715800

  3. Polyplacophora (Mollusca from reef ecosystems and associations with macroalgae on the Coast of Alagoas, Northeastern Brazil

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    Monica Dorigo Correia

    2015-08-01

    Full Text Available ABSTRACT Brazilian marine molluscs, especially Gastropoda and Bivalvia, are relatively well studied. However, information on the class Polyplacophora is more scarce, particularly on reef-dwelling forms. This study aimed to qualitatively and quantitatively analyze aspects of polyplacophorans from reef ecosystems and their associations with macroalgae on the coast of Maceió (state of Alagoas, Brazilian Northeast. The study area included five coral reefs at Ipioca, Ponta do Prego, Ponta do Meirim, Riacho Doce and Ponta Verde, as well as two sandstone reefs, located in Guaxuma and Sereia. The samples were obtained by snorkelling along the intertidal and subtidal reef zones to a depth of up to five meters during low tides, between 2009 and 2011. In addition, the chitons associated with three macroalgae of the Ponta Verde coral reef were studied based on collections made over 12 years (from the summer of 1998 to the winter of 2009. Three replicates with an area of 25 cm2 were collected from each of the following species of macroalgal phytals: Amphiroa fragilissima (Rhodophyta, Caulerpa racemosa (Chlorophyta and Dictyota cervicornis (Phaeophyta. A total of 715 individuals (110 juveniles and 605 adults were identified, including Acanthochitona terezae Guerra, 1983, Ischnochiton striolatus (Gray, 1828 and Ischnoplax pectinata (Sowerby II, 1840. Acanthochitona terezae was found for the first time in the area. Ischnochiton striolatus was the most abundant species in the reef ecosystem and in association with macroalgae. The greatest number of individuals of all three polyplacophorans identified (adults and juveniles was found on the phytal A. fragilissima.

  4. Associative Memory in Three Aplysiids: Correlation with Heterosynaptic Modulation

    Science.gov (United States)

    Thompson, Laura; Wright, William G.; Hoover, Brian A.; Nguyen, Hoang

    2006-01-01

    Much recent research on mechanisms of learning and memory focuses on the role of heterosynaptic neuromodulatory signaling. Such neuromodulation appears to stabilize Hebbian synaptic changes underlying associative learning, thereby extending memory. Previous comparisons of three related sea-hares (Mollusca, Opisthobranchia) uncovered interspecific…

  5. 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

  6. Comparative mapping of GABA-immunoreactive neurons in the central nervous systems of nudibranch molluscs.

    Science.gov (United States)

    Gunaratne, Charuni A; Sakurai, Akira; Katz, Paul S

    2014-03-01

    The relative simplicity of certain invertebrate nervous systems, such as those of gastropod molluscs, allows behaviors to be dissected at the level of small neural circuits composed of individually identifiable neurons. Elucidating the neurotransmitter phenotype of neurons in neural circuits is important for understanding how those neural circuits function. In this study, we examined the distribution of γ-aminobutyric-acid;-immunoreactive (GABA-ir) neurons in four species of sea slugs (Mollusca, Gastropoda, Opisthobranchia, Nudibranchia): Tritonia diomedea, Melibe leonina, Dendronotus iris, and Hermissenda crassicornis. We found consistent patterns of GABA immunoreactivity in the pedal and cerebral-pleural ganglia across species. In particular, there were bilateral clusters in the lateral and medial regions of the dorsal surface of the cerebral ganglia as well as a cluster on the ventral surface of the pedal ganglia. There were also individual GABA-ir neurons that were recognizable across species. The invariant presence of these individual neurons and clusters suggests that they are homologous, although there were interspecies differences in the numbers of neurons in the clusters. The GABAergic system was largely restricted to the central nervous system, with the majority of axons confined to ganglionic connectives and commissures, suggesting a central, integrative role for GABA. GABA was a candidate inhibitory neurotransmitter for neurons in central pattern generator (CPG) circuits underlying swimming behaviors in these species, however none of the known swim CPG neurons were GABA-ir. Although the functions of these GABA-ir neurons are not known, it is clear that their presence has been strongly conserved across nudibranchs. PMID:24638845

  7. Nyctemeral variations of magnesium intake in the calcitic layer of a Chilean mollusk shell ( Concholepas concholepas, Gastropoda)

    Science.gov (United States)

    Lazareth, Claire E.; Guzman, Nury; Poitrasson, Franck; Candaudap, Frederic; Ortlieb, Luc

    2007-11-01

    Mollusk shells are increasingly used as records of past environmental conditions, particularly for sea-surface temperature (SST) reconstructions. Many recent studies tackled SST (and/or sea-surface salinity) tracers through variations in the elementary (Mg and Sr) or stable isotope (δ 18O) composition within mollusk shells. But such attempts, which sometimes include calibration studies on modern specimens, are not always conclusive. We present here a series of Mg and Sr analyses in the calcitic layer of Concholepas concholepas (Muricidae, Gastropoda) with a very high time-resolution on a time window covering about 1 and a half month of shell formation, performed by Laser Ablation Inductively-Coupled Plasma Mass Spectrometry (LA-ICP-MS) and electron probe micro-analysis (EPMA). The selected specimen of this common Chilean gastropod was grown under controlled environmental conditions and precise weekly time-marks were imprinted in the shell with calcein staining. Strontium variations in the shell are too limited to be interpreted in terms of environmental parameter changes. In contrast, Mg incorporation into the shell and growth rate appear to change systematically between night and day. During the day, Mg is incorporated at a higher rate than at night and this intake seems positively correlated with water temperature. The nightly reduced Mg incorporation is seemingly related to metabolically controlled processes, formation of organic-rich shell increments and nocturnal feeding activity of the animals. The nyctemeral Mg changes in the C. concholepas shell revealed in this study might explain at least part of the discrepancies observed in previous studies on the use of Mg as a SST proxy in mollusk shells. In the case of C. concholepas, Mg cannot be used straightforwardly as a SST proxy.

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

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    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

  9. Descripción de un nuevo limácido de Menorca (Islas Baleares: Gigantomilax (Vitrinoides benjaminus sp. n. (Gastropoda, Pulmonata

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    Borredà, V.

    2008-06-01

    Full Text Available Descripción de un nuevo limácido de Menorca (Islas Baleares: Gigantomilax (Vitrinoides benjaminus sp. n. (Gastropoda, Pulmonata We describe a new endemic limacid slug, Gigantomilax (Vitrinoides benjaminus n. sp. and we compare it with the nearest species, particularly with Gigantomilax (V. majoricensis, another Balearic endemism. Characteristic features of this new species include its small size, translucid and smooth body, and totally grey dorsum with no bands or spots. The reproductive system shows a well developed vas deferens surrounded by the distal part of prostatic gland, a thin penial retractor muscle, swollen prostate and small distal genitalia. The recent redescription of Limax majoricensis by Wiktor et al. (2007 is discussed and we consider that these authors refer to G. benjaminus n. sp., and so we dessign the neotype of Gigantomilax (V. majoricensis.

  10. New location for Bulinus truncatus (Audouin, 1827 (Gastropoda: Planorbidae intermediate host of Schistosoma haematobium and its distribution in the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Dana, Elías D.

    2015-12-01

    Full Text Available This paper reports a new population of Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae found in the province of Almería (Southeast Spain. B. truncatus is an intermediate host of Schistosoma haematobium, the trematode which causes urinary schistosomiasis in humans. Individuals were identified to species level by double-nested PCR, resulting in 100% homology. This population is located under the driest climate conditions of the Iberian Peninsula. Data on the distribution of this species in the Iberian Peninsula was gathered and is provided in this paper. Improved knowledge of the distribution of Bulinus truncatus is key to assess the risk of new outbreaks of schistosomiasis in the Iberian Peninsula.En este trabajo se reporta una nueva población de Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae en la provincia de Almería (Sureste de España. Se trata de una especie que presenta considerable interés tanto zoológico como epidemiológico por su papel como hospedador intermediario de Schistosoma haematobium, responsable de la esquistosomiasis urogenital humana. Los ejemplares fueron determinados a nivel específico mediante PCR doble anidada, con un 100% de homología. Se trata de la población localizada más al Sureste y en condiciones de mayor aridez en la península Ibérica. Se recopilaron los datos de presencia publicados para conocer su distribución en la península. El conocimiento de la distribución de Bulinus truncatus es una pieza clave para evaluar el riesgo de nuevos focos de esquistosomiasis en la península Ibérica.

  11. Packaging and Delivery of Chemical Weapons: A Defensive Trojan Horse Stratagem in Chromodorid Nudibranchs

    OpenAIRE

    Carbone, Marianna; Gavagnin, Margherita; Haber, Markus; Guo, Yue-Wei; Fontana, Angelo; Manzo, Emiliano; Genta-Jouve, Gregory; Tsoukatou, Maria; Rudman, William B.; Cimino, Guido; Ghiselin, Michael T.; Mollo, Ernesto

    2013-01-01

    Background Storage of secondary metabolites with a putative defensive role occurs in the so-called mantle dermal formations (MDFs) that are located in the more exposed parts of the body of most and very likely all members of an entire family of marine mollusks, the chromodorid nudibranchs (Gastropoda: Opisthobranchia). Given that these structures usually lack a duct system, the mechanism for exudation of their contents remains unclear, as does their adaptive significance. One possible explana...

  12. Divergencia intraespecífica y código de barras de ADN en Systrophia helicycloides (Gastropoda, Scolodontidae

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    Pedro Romero

    2011-08-01

    Full Text Available El DNA barcoding es un análisis que se basa en la comparación de distancias genéticas para identificar especies utilizando principalmente un segmento del gen Citocromo C Oxidasa I (COI. Los retos para la identificación surgen al estudiar grupos que presentan gran diversidad genética como los moluscos. Por ello, los objetivos de nuestra investigación fueron estimar la divergencia intraespecífica en el molusco terrestre amazónico Systrophia helicycloides (Gastropoda, Scolodontidae y evaluar la utilización de los códigos de barras de ADN en la identificación molecular de esta especie. Las secuencias de nucleótidos fueron comparadas con las bases de datos Genbank y BOLD (Barcode of Life Data Systems. Se realizó un análisis de distancia genética mediante Neighbour Joining. Systrophia helicycloides presentó dos grupos de haplotipos con distancias genéticas intraespecíficas mayores a 4%. También se observó una superposición entre las distancias intraespecíficas y las interespecíficas. La gran divergencia intraespecífica puede estar relacionada a la rápida variación del genoma mitocondrial, la distribución poblacional de los moluscos la cual permite el aislamiento y diferenciación genética, y la presencia de polimorfismos ancestrales. Los perfiles COI enviados a la base de datos BOLD son los primeros registros para esta especie y permitieron diferenciar a Systrophia helicycloides de otras especies. Estos perfiles corroboran la gran variación que ocurre en el genoma mitocondrial de moluscos terrestres por lo que la asignación de especies en este grupo precisa de la combinación entre los valores de divergencia genética, la evaluación de sitios informativos y los estudios de taxonomía convencional.

  13. 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.

  14. Screening of antiangiogenic potential of twenty two marine invertebrate extracts of phylum Mollusca from South East Coast of India

    Institute of Scientific and Technical Information of China (English)

    Pankaj Gupta; Muthuvel Arumugam; Raj Vardhan Azad; Rohit Saxena; Supriyo Ghose; Nihar Ranjan Biswas; Thirumurthy Velpandian

    2014-01-01

    Objective: To evaluate the antiangiogenic potential of twenty two marine invertebrate species of Phylum Mollusca from south east coast of India.Methods:Live specimens of molluscan species were collected and their methanolic extracts were evaluated for preliminary antiangiogenic activity using the in ovo chick chorio-allantoic membrane assay. The extracts were further evaluated for in vivo antiangiogenic activity using chemical cautery induced corneal neovascularization assay in rats and oxygen induced retinopathy assay in rat pups.Results:In the chick chorio-allantoic membrane assay, four methanolic extracts of marine molluscan species viz. Meretrix meretrix, Meretrix casta, Telescopium telescopium and Bursacrumena methanolic extracts exhibited noticeable antiangiogenic activity at the tested concentration of 200 µg whereby they significantly inhibited the VEGF induced proliferation of new blood vessels. Among these four extracts, the methanolic extract of Meretrix casta exhibited relatively higher degree of antiangiogenic activity with an inhibitiory percentage (64.63%) of the VEGF induced neovascularization followed by the methanolic extracts of Telescopium telescopium (62.02%), Bursa crumena (60.48%) and Meretrix meretrix (47.01%). These four methanolic extracts were further evaluated for in vivo antiangiogenic activity whereby the methanolic extract of Telescopium telescopium exhibited most noticeable inhibition (42.58%) of the corneal neovascularization in rats in comparison to the sham treated group, and also exhibited most noticeable inhibition (31.31%) of the oxygen induced retinal neovascularization in rat pups in comparison to the hyperoxia group that was observed for considerable retinal neovascularization.Conclusions:The significant antiangiogenic activity evinced by the extract of Telescopium telescopium merits further investigation for ocular neovascular diseases.

  15. Present status of the endangered limpet Cymbula nigra (Gastropoda, Patellidae in Ceuta: how do substrate heterogeneity and area accessibility affect population structure?

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    Rivera–Ingraham, G. A.

    2011-12-01

    Full Text Available Cymbula nigra (Gastropoda, Patellidae is a threatened giant patellid limpet found on the North African coast from Namibia to Algeria. The objective of this study was to estimate the total number of individuals present in Ceuta (Strait of Gibraltar and to determine the effect of certain physical parameters on population structure and abundance. Between 2006 and 2010 we conducted an exhaustive census in the area. Results indicate that Ceuta could be home to 48,473 individuals. The most important populations were recorded on the North Bay, characterized by its Atlantic influence. While for other similar species, such as Patella ferruginea, human accessibility to the area plays an important role in determining the structure of populations, we found that substrate roughness (small scale topographic heterogeneity is the main determining factor in this species. Populations located on medium to low topographic heterogeneity substrates showed higher percentages of medium and large size individuals. However, recruitment rates did not differ between substrata of different roughness. Finally, and through the analysis of the C. nigra populations located on some recently constructed jetties, we obtained interesting new data regarding individual growth rates, thus contributing to our knowledge of the population structure of the species.

  16. Relationship between anti-oxidant capacity and manganese accumulation in the soft tissues of two freshwater molluscs: Unio pictorum mancus (Lamellibranchia, Unionidae and Viviparus ater (Gastropoda, Prosobranchia

    Directory of Open Access Journals (Sweden)

    Oscar RAVERA

    2005-08-01

    Full Text Available Manganese is an element of great importance in the life cycle of plants and animals. For example, it plays an essential role as an activator of various enzymatic systems such as isoenzymes of superoxide dismutase. Freshwater Unionidae concentrate relatively large amounts of manganese in their tissues, but little is known about the physiological role of this metal. The aim of this research is to acquire a better knowledge of the role of manganese in molluscs which accumulate large amounts of this metal and in those with low manganese concentrations. As manganese is one of the metals present in the superoxide molecule, the possible relationship between manganese concentration in the soft tissues of molluscs and the antioxidant capacity of the metal can usefully be tested. To this end two species of molluscs were analysed: Unio pictorum mancus (Lamellibranchia, Unionidae, which is very rich in manganese, and Viviparus ater (Gastropoda, Prosobranchia which has a low manganese content. The adults of both species were analysed for manganese concentration by ICP, and for antioxidant capacity as RAC (Relative Antioxidant Capacity by a superoxide dismutase method. The results clearly demonstrate the active role played by manganese against free radicals and consequently the important role of the metal in protecting Unio against oxidative stress. The low concentration of manganese in Viviparus may be the result of the effective excretion of this metal, as was found for ruthenium.

  17. Identification of Genes Related to Learning and Memory in the Brain Transcriptome of the Mollusc, "Hermissenda Crassicornis"

    Science.gov (United States)

    Tamvacakis, Arianna N.; Senatore, Adriano; Katz, Paul S.

    2015-01-01

    The sea slug "Hermissenda crassicornis" (Mollusca, Gastropoda, Nudibranchia) has been studied extensively in associative learning paradigms. However, lack of genetic information previously hindered molecular-level investigations. Here, the "Hermissenda" brain transcriptome was sequenced and assembled de novo, producing 165,743…

  18. A preliminary study of iron isotope fractionation in marine invertebrates (chitons, Mollusca) in near-shore environments

    Science.gov (United States)

    Emmanuel, S.; Schuessler, J. A.; Vinther, J.; Matthews, A.; von Blanckenburg, F.

    2014-10-01

    Chitons (Mollusca) are marine invertebrates that produce radulae (teeth or rasping tongues) containing high concentrations of biomineralized magnetite and other iron-bearing minerals. As Fe isotope signatures are influenced by redox processes and biological fractionation, Fe isotopes in chiton radulae might be expected to provide an effective tracer of ambient oceanic conditions and biogeochemical cycling. Here, in a pilot study to measure Fe isotopes in marine invertebrates, we examine Fe isotopes in modern marine chiton radulae collected from different locations in the Atlantic and Pacific oceans to assess the range of isotopic values, and to test whether or not the isotopic signatures reflect seawater values. Values of δ56Fe (relative to IRMM-014) in chiton teeth range from -1.90 to 0.00 ‰ (±0.05‰ (2σ) uncertainty in δ56Fe), probably reflecting a combination of geographical control and biological fractionation processes. Comparison with published local surface seawater Fe isotope data shows a consistent negative offset of chiton teeth Fe isotope compositions relative to seawater. Strikingly, two different species from the same locality in the North Pacific (Puget Sound, Washington, USA) have distinct isotopic signatures. Tonicella lineata, which feeds on red algae in the sublittoral zone, has a mean δ56Fe of -0.65 ± 0.26‰ (2σ, 3 specimens), while Mopalia muscosa, which feeds on both green and red algae in the eulittoral zone, shows lighter isotopic values with a mean δ56Fe of -1.47 ± 0.98‰ (2σ, 5 specimens). Three possible pathways are proposed to account for the different isotopic signatures: (i) physiologically controlled processes within the chitons that lead to species-dependent fractionation; (ii) diet-controlled variability due to different Fe isotope fractionation in the red and green algal food sources; and (iii) environmentally controlled fractionation that causes variation in the isotopic signatures of bioavailable Fe in the different

  19. 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)

  20. Complete mitochondrial genome of Coelomactra antiquata (Mollusca: Bivalvia): The first representative from the family Mactridae with novel gene order and unusual tandem repeats.

    Science.gov (United States)

    Meng, Xueping; Zhao, Nana; Shen, Xin; Hao, Jue; Liang, Meng; Zhu, Xiaolin; Cheng, Hanliang; Yan, Binlun; Liu, Zhaopu

    2012-06-01

    The complete mitochondrial genome plays an important role in the accurate inference of phylogenetic relationships among metazoans. Mactridae, also known as trough shells or duck clams, is an important family of marine bivalve clams in the order Veneroida. Here we present the complete mitochondrial genome sequence of the Xishishe Coelomactra antiquata (Mollusca: Bivalvia), which is the first representative from the family Mactridae. The mitochondrial genome of C. antiquata is of 17,384bp in length, and encodes 35 genes, including 12 protein-coding, 21 transfer RNA, and 2 ribosomal RNA genes. Compared with the typical gene content of animal mitochondrial genomes, atp8 and tRNAS(2) are missing. Gene order of the mitochondrial genome of C. antiquata is unique compared with others from Veneroida. In the mitochondrial genome of the C. antiquata, a total of 2189bp of non-coding nucleotides are scattered among 26 non-coding regions. The largest non-coding region contains one section of tandem repeats (99 bp×11), which is the second largest tandem repeats found in the mitochondrial genomes from Veneroida. The phylogenetic trees based on mitochondrial genomes support the monophyly of Veneridae and Lucinidae, and the relationship at the family level: ((Veneridae+Mactridae)+(Cardiidae+Solecurtidae))+Lucinidae. The phylogenetic result is consistent with the morphological classification. Meanwhile, bootstrap values are very high (BP=94-100), suggesting that the evolutionary relationship based on mitochondrial genomes is very reliable.

  1. Crawling through time: Transition of snails to slugs dating back to the Paleozoic, based on mitochondrial phylogenomics.

    Science.gov (United States)

    Medina, Mónica; Lal, Shruti; Vallès, Yvonne; Takaoka, Tori L; Dayrat, Benoît A; Boore, Jeffrey L; Gosliner, Terrence

    2011-03-01

    Sea slugs (Gastropoda: Opisthobranchia) are characterized by extensive morphological homoplasy. In particular, reduced or absent shells are predominant throughout the group. This trend towards shell loss has resulted in a poor fossil record. DNA-based phylogenies have been helpful in improving our understanding of the evolution of this group and major clades are emerging. We report 13 new complete opisthobranch mitochondrial genomes that provide robust support for some of these emerging nodes. We name three new clades within the Opisthobranchia, the Actopleura (Acteonoidea plus Nudipleura), Placoesophaga (Cephalaspidea plus Anaspidea), and Siphoglossa (Sacoglossa plus the Siphonaria). Finally we use molecular clock dating that suggests an earlier opisthobranch divergence than previously reported. The implications of this evolutionary scenario are discussed. PMID:21429465

  2. Supercooling ability in two populations of the land snail Helix pomatia (Gastropoda: Helicidae) and ice-nucleating activity of gut bacteria.

    Science.gov (United States)

    Nicolai, Annegret; Vernon, Philippe; Lee, Marcia; Ansart, Armelle; Charrier, Maryvonne

    2005-02-01

    The land snail Helix pomatia (Gastropoda: Helicidae) is widely distributed in Northern and Central Europe where it may experience subzero temperatures during winter months. Its supercooling ability was studied in two populations of H. pomatia. One population originated from Southern Sweden (Gotaland) and the other from Central France (Auvergne). In the experimental design, they were acclimated, over 2 weeks, to artificial winter conditions (hibernation, T=5 degrees C). The Swedish snails showed a rather limited supercooling ability (temperature of crystallization, T(c)=-6.4+/-0.8 degrees C), significantly greater, however, than the supercooling capacity of the population from France (T(c)=-4.6+/-1.4 degrees C). In artificial spring conditions (3 months of hibernation followed by a progressive acclimation, over 2 weeks, to activity at T=20 degrees C), both populations exhibited a similar high T(c) (-2.0+/-1.0 degrees C). The lower T(c) of hibernating Swedish snails could be due to a greater loss of body water, accompanied by a higher concentration of solutes in the hemolymph. In both populations, the variation in hemolymph osmolality measured between hibernating (250-270 mOsm kg(-1)) and active (165-215 mOsm kg(-1)) snails may be explained by the variation in body water mass and did not suggest the production of colligative cryoprotectants. Moreover, the three bacterial strains, Buttiauxella sp., Kluyvera sp., and Tatumella sp. (Enterobacteriaceae) which were isolated from fed snails, but absent in starved snails, did not show any ice-nucleating activity at temperatures higher than -9 degrees C. Only the strain Kluyvera sp. initiated nucleation at -9 degrees C. This strain, therefore, is a weak, also termed a Type III or Class C ice-nucleating active bacterium, but with no influence on the supercooling ability of individual snails. In summary, fluctuations in body water mass of hibernating snail populations, triggering changes in osmolyte concentration, rather than

  3. The Mitochondrial Genomes of the Nudibranch Mollusks, Melibe leonina and Tritonia diomedea, and Their Impact on Gastropod Phylogeny.

    Directory of Open Access Journals (Sweden)

    Joseph L Sevigny

    Full Text Available The phylogenetic relationships among certain groups of gastropods have remained unresolved in recent studies, especially in the diverse subclass Opisthobranchia, where nudibranchs have been poorly represented. Here we present the complete mitochondrial genomes of Melibe leonina and Tritonia diomedea (more recently named T. tetraquetra, two nudibranchs from the unrepresented Cladobranchia group, and report on the resulting phylogenetic analyses. Both genomes coded for the typical thirteen protein-coding genes, twenty-two transfer RNAs, and two ribosomal RNAs seen in other species. The twelve-nucleotide deletion previously reported for the cytochrome oxidase 1 gene in several other Melibe species was further clarified as three separate deletion events. These deletions were not present in any opisthobranchs examined in our study, including the newly sequenced M. leonina or T. diomedea, suggesting that these previously reported deletions may represent more recently divergent taxa. Analysis of the secondary structures for all twenty-two tRNAs of both M. leonina and T. diomedea indicated truncated d arms for the two serine tRNAs, as seen in some other heterobranchs. In addition, the serine 1 tRNA in T. diomedea contained an anticodon not yet reported in any other gastropod. For phylogenetic analysis, we used the thirteen protein-coding genes from the mitochondrial genomes of M. leonina, T. diomedea, and seventy-one other gastropods. Phylogenetic analyses were performed for both the class Gastropoda and the subclass Opisthobranchia. Both Bayesian and maximum likelihood analyses resulted in similar tree topologies. In the Opisthobranchia, the five orders represented in our study were monophyletic (Anaspidea, Cephalaspidea, Notaspidea, Nudibranchia, Sacoglossa. In Gastropoda, two of the three traditional subclasses, Opisthobranchia and Pulmonata, were not monophyletic. In contrast, four of the more recently named gastropod clades (Vetigastropoda

  4. The Mitochondrial Genomes of the Nudibranch Mollusks, Melibe leonina and Tritonia diomedea, and Their Impact on Gastropod Phylogeny.

    Science.gov (United States)

    Sevigny, Joseph L; Kirouac, Lauren E; Thomas, William Kelley; Ramsdell, Jordan S; Lawlor, Kayla E; Sharifi, Osman; Grewal, Simarvir; Baysdorfer, Christopher; Curr, Kenneth; Naimie, Amanda A; Okamoto, Kazufusa; Murray, James A; Newcomb, James M

    2015-01-01

    The phylogenetic relationships among certain groups of gastropods have remained unresolved in recent studies, especially in the diverse subclass Opisthobranchia, where nudibranchs have been poorly represented. Here we present the complete mitochondrial genomes of Melibe leonina and Tritonia diomedea (more recently named T. tetraquetra), two nudibranchs from the unrepresented Cladobranchia group, and report on the resulting phylogenetic analyses. Both genomes coded for the typical thirteen protein-coding genes, twenty-two transfer RNAs, and two ribosomal RNAs seen in other species. The twelve-nucleotide deletion previously reported for the cytochrome oxidase 1 gene in several other Melibe species was further clarified as three separate deletion events. These deletions were not present in any opisthobranchs examined in our study, including the newly sequenced M. leonina or T. diomedea, suggesting that these previously reported deletions may represent more recently divergent taxa. Analysis of the secondary structures for all twenty-two tRNAs of both M. leonina and T. diomedea indicated truncated d arms for the two serine tRNAs, as seen in some other heterobranchs. In addition, the serine 1 tRNA in T. diomedea contained an anticodon not yet reported in any other gastropod. For phylogenetic analysis, we used the thirteen protein-coding genes from the mitochondrial genomes of M. leonina, T. diomedea, and seventy-one other gastropods. Phylogenetic analyses were performed for both the class Gastropoda and the subclass Opisthobranchia. Both Bayesian and maximum likelihood analyses resulted in similar tree topologies. In the Opisthobranchia, the five orders represented in our study were monophyletic (Anaspidea, Cephalaspidea, Notaspidea, Nudibranchia, Sacoglossa). In Gastropoda, two of the three traditional subclasses, Opisthobranchia and Pulmonata, were not monophyletic. In contrast, four of the more recently named gastropod clades (Vetigastropoda, Neritimorpha

  5. 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. PMID:21364693

  6. MOLECULAR PHYLOGENY OF THE NERITIDAE (GASTROPODA: NERITIMORPHA BASED ON THE MITOCHONDRIAL GENES CYTOCHROME OXIDASE I (COI AND 16S rRNA

    Directory of Open Access Journals (Sweden)

    Julián Fernando Quintero Galvis

    2013-06-01

    Full Text Available The family Neritidae has representatives in tropical and subtropical regions that occur in a variety of environments, and its known fossil record dates back to the late Cretaceous. However there have been few studies of molecular phylogeny in this family. We performed a phylogenetic reconstruction of the family Neritidae using the COI (722 bp and the 16S rRNA (559 bp regions of the mitochondrial genome. Neighbor-joining, maximum parsimony and Bayesian inference were performed.The best phylogenetic reconstruction was obtained using the COI region, and we consider it an appropriate marker for phylogenetic studies within the group. Consensus analysis (COI +16S rRNA generally obtained the same tree topologies and confirmed that the genus Nerita is monophyletic. The consensus analysis using parsimony recovered a monophyletic group consisting of the genera Neritina, Septaria, Theodoxus, Puperita, and Clithon, while in the Bayesian analyses Theodoxus is separated from the other genera. The phylogenetic status of the species from the genus Nerita from the Colombian Caribbean generated in this study was consistent with that reported for the genus in previous studies. In the resulting consensus tree obtained using maximum parsimony, we included information on habitat type for each species, to map the evolution by habitat. Species of the family Neritidae possibly have their origin in marine environments, which is consistent with conclusions from previous reports based on anatomical studies.Filogenia molecular de la familia Neritidae (Gastropoda: Neritimorpha con base en los genes mitocondriales citocromo oxidasa I (COI y 16S rRNALa familia Neritidae cuenta con representantes en regiones tropicales y subtropicales adaptadas a diferentes ambientes, con un registro fósil que data para finales del Cretáceo. Sin embargo no se han realizado estudios de filogenia molecular en la familia. En este estudio se realizó una reconstrucción filogen

  7. The Diversity of Molluscas Was Applied to Monitor the Heavy Metals in the Huayuan River%软体动物多样性在花垣河水体重金属监测中的应用

    Institute of Scientific and Technical Information of China (English)

    刘俊; 郑济芳; 胡南; 胡劲松; 朱允华; 刘运莲; 殷杰

    2009-01-01

    对湘西花垣河软体动物多样性与重金属污染状况进行了调查.在花垣河8个监测断面中,除S1、S3、S8的软体动物丰富度指数(DMA)与Shannon-Wiener多样性指数(H′)分别介于0.264 3-2.493 7和0.676 5-2.412 3外,S2、S4、S5、S7、S8五个断面的软体动物丰富度和多样性指数均为零.Mn、Cd、Pb、Cu、Zn在花垣河8个监测断面的河水中都能检测到,其中Mn、Cd含量严重超出GB的Ⅴ类水标准.软体动物多样性监测与理化监测的结果均表明,花垣河水体已经受到严重重金属污染.%The diversities of molluscas and the pollution of heavy metals in the Xiangxi Huayuan River were investigated.The species richness indexes (DMA) and Shannon-Wiener diversity indexes (H′) of mollusca at S1,S3,S8 were 0.264 3-2.493 7 and 0.676 5-2.412 3,respectively.The DMA and H′ at the other 5 sections were zero.Mn、Cd、Pb、Cu、Zn were identified in the water,the concentrantions of Mn and Cd were severe exceed the standard of limits of Ⅴ class water of GB.The results of the diversities of molluscas and the physico-chemical monitoring suggested that the water of the Huayuan River had been polluted by heavy metals severity.

  8. Introducción al estudio de los gasterópodos (Mollusca de la laguna de Montcortès (Pallars Sobirà, Cataluña, NE de la península ibérica

    Directory of Open Access Journals (Sweden)

    V. Bros

    2009-01-01

    Full Text Available Introduction to the study of gastropods (Mollusca on the Montcortés lake (Pallars Sobirà, Catlonia, NE of the Iberian peninsulaThe check-list of 50 species of terrestrial gastro­pod and freshwater molluscs in the Montcortès lake (Catalonia, Spain and its environs, pertaining to 24 different families, is shown. Thirty-three species are cited for the first time in the area of study. The unpublished data on their distribution and ecological requirements are contributed. The preliminary results indicate us that the communities of molluscs that accompany to the helofitic vegetation and the higrofits well are formed with elements of high faunistic and ecological interest. Simultaneously, some recommendations for the protection of the malacological fauna of the lake are commented.

  9. Molluscicidal activity of various solvent extracts from Solanum nigrum var. villosum L. aerial parts against Galba truncatula

    OpenAIRE

    Hammami H.; Mezghani-Jarraya R.; Damak M.; Ayadi A.

    2011-01-01

    Molluscicidal activity of Solanum nigrum var. villosum (morelle velue) extracts and their fractions were tested against the mollusca gastropoda Galba truncatula intermediate host of Fasciola hepatica. The results indicated that the hydro-methanol (MeOH-H2O) immature fruit extract possess the highest molluscicidal activity (LC50 = 3.96 mg/L) against Galba truncatula compared with other tested compounds. After acido-basic treatment, the methanolic extract fraction isolated from the immature fru...

  10. A new species of Acteon (Opisthobranchia: Acteonidae from Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Carlo Magenta Cunha

    2011-04-01

    Full Text Available A new species of Acteon Montfort 1810, Acteon mirim sp. nov., from Canopus Bank, state of Ceará, Brazil is described based on shell morphology. The new species is compared with other species of the genus reported from Brazil. It differs from other Brazilian species in having a whitish color with dark orange-brown spiral bands and a shell surface covered with small spiral grooves, regularly rectangular.

  11. 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.

  12. 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

  13. 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.                   

  14. 后鳃亚纲软体动物化学防御物质研究进展%Research eevelopment on chemically defensive substances of opisthobranch molluscs

    Institute of Scientific and Technical Information of China (English)

    张文; 郭跃伟

    2007-01-01

    海洋后鳃亚纲软体动物(Opisthobranchia) 属软体动物门(Mollusca) 复足纲软体动物(Gastropoda),其成体体表的被壳或退化或完全消失.由于失去了物理保护,海洋后鳃亚纲软体动物的生存主要依赖于化学防御机制.大多数海洋后鳃亚纲软体动物通过选择适当的食物,并将其中有用的代谢物质经过进一步生物转化或积累到身体的特定部位作为化学防御性物质,以保护自己不受天敌的捕食;少数动物能够生物合成自身所需要的化学物质,从而建立其化学防御体系.显然,研究后鳃亚纲软体动物及其食源生物的化学组成,可以揭示它们之间的食物链关系,并进一步阐明这些化学物质的生态学作用.由于相同软体动物在食性上具有统一性,因此对其体内化学成分的分析也有助于其分类学的研究.同时,这种进化的化学防御体系为我们提供了一条从自然界寻找生物活性物质的新方法.基于以上原因,来自生态学、化学以及药理学等不同领域的科学家均对海洋后鳃亚纲软体动物表现出极大的兴趣,并对其进行了一系列研究;在过去的20多年中,发表了大量的相关论文.综述了海洋后鳃亚纲软体动物近5a来的研究概况,文章涵盖了所有研究的3个大的种群,旨在向读者介绍有关该类动物的化学研究情况,并据此讨论其可能的生态作用.

  15. Life cycle and structure of the fish digenean Brachyphallus crenatus (Hemiuridae).

    Science.gov (United States)

    Køie, M

    1992-04-01

    Cystophorous cercariae from Retusa obtusa (Montagu) (Gastropoda, Opisthobranchia, Retusidae) develop into adults of Brachyphallus crenatus (Rudolphi, 1802) Odhner, 1905 (Hemiuridae). The free-swimming cercariae were ingested by laboratory-reared Acartia tonsa Dana, and the cercarial body was injected into the hemocoel of the copepod. Two-week-old metacercariae held at 15 C were infective to stickleback Gasterosteus aculeatus Linnaeus. The cercariae of B. crenatus are very similar to the cercariae of Hemiurus luehei Odhner, 1905, and Lecithocladium excisum (Rudolphi, 1819) Lühe, 1901 (Hemiuridae), which develop in closely related opisthobranch snails. Scanning electron microscopy of metacercariae and adults of B. crenatus revealed the annular plications of most of the external surface to be scalelike. The area surrounding the genital pore and the presomatic pit was densely plicated. PMID:1556648

  16. Details of gastropod phylogeny inferred from 18S rRNA sequences.

    Science.gov (United States)

    Winnepenninckx, B; Steiner, G; Backeljau, T; De Wachter, R

    1998-02-01

    Some generally accepted viewpoints on the phylogenetic relationships within the molluscan class Gastropoda are reassessed by comparing complete 18S rRNA sequences. Phylogenetic analyses were performed using the neighbor-joining and maximum parsimony methods. The previously suggested basal position of Archaeogastropoda, including Neritimorpha and Vetigastropoda, in the gastropod clade is confirmed. The present study also provides new molecular evidence for the monophyly of both Caenogastropoda and Euthyneura (Pulmonata and Opisthobranchia), making Prosobranchia paraphyletic. The relationships within Caenogastropoda and Euthyneura data turn out to be very unstable on the basis of the present 18S rRNA sequences. The present 18S rRNA data question, but are insufficient to decide on, muricacean (Neogastropoda), neotaenioglossan, pulmonate, or stylommatophoran monophyly. The analyses also focus on two systellommatophoran families, namely, Veronicellidae and Onchidiidae. It is suggested that Systellommatophora are not a monophyletic unit but, due to the lack of stability in the euthyneuran clade, their affinity to either Opisthobranchia or Pulmonata could not be determined. PMID:9479694

  17. Complete DNA sequence of the mitochondrial genome of the sea-slug, Aplysia californica: conservation of the gene order in Euthyneura.

    Science.gov (United States)

    Knudsen, Bjarne; Kohn, Andrea B; Nahir, Ben; McFadden, Catherine S; Moroz, Leonid L

    2006-02-01

    We have sequenced and characterized the complete mitochondrial genome of the sea slug, Aplysia californica, an important model organism in experimental biology and a representative of Anaspidea (Opisthobranchia, Gastropoda). The mitochondrial genome of Aplysia is in the small end of the observed sizes of animal mitochondrial genomes (14,117 bp, NCBI Accession No. NC_005827). The Aplysia genome, like most other mitochondrial genomes, encodes genes for 2 ribosomal subunit RNAs (small and large rRNAs), 22 tRNAs, and 13 protein subunits (cytochrome c oxidase subunits 1-3, cytochrome b apoenzyme, ATP synthase subunits 6 and 8, and NADH dehydrogenase subunits 1-6 and 4L). The gene order is virtually identical between opisthobranchs and pulmonates, with the majority of differences arising from tRNA translocations. In contrast, the gene order from representatives of basal gastropods and other molluscan classes is significantly different from opisthobranchs and pulmonates. The Aplysia genome was compared to all other published molluscan mitochondrial genomes and phylogenetic analyses were carried out using a concatenated protein alignment. Phylogenetic analyses using maximum likelihood based analyses of the well aligned regions of the protein sequences support both monophyly of Euthyneura (a group including both the pulmonates and opisthobranchs) and Opisthobranchia (as a more derived group). The Aplysia mitochondrial genome sequenced here will serve as an important platform in both comparative and neurobiological studies using this model organism. PMID:16230032

  18. Clausiliidae (Gastropoda, Pulmonata) from western New Guinea

    NARCIS (Netherlands)

    Loosjes, F.E.

    1956-01-01

    During the zoological exploration of Netherlands New Guinea sponsored by the Rijksmuseum van Natuurlijke Historie, Leiden, in 1954-1955, four specimens of Clausiliidae were found. There are no previous records of the occurrence of Clausiliidae in New Guinea; the most eastern locality in the Indo-Aus

  19. 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)

    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

  20. Naked in toxic fluids: A nudibranch mollusc from hydrothermal vents

    Science.gov (United States)

    Valdés, Ángel; Bouchet, Philippe

    1998-01-01

    A new species of the nudibranch genus Dendronotus (Mollusca, Opisthobranchia) is reported from a hydrothermal vent at the Lucky Strike area, on the Mid-Atlantic Ridge. This is the first species of nudibranch recorded with certainty from a vent site. Other species of Dendronotus are distributed in temperate waters on the continental shelf of the northern hemisphere. Two factors that probably account for the occurrence of a nudibranch in this hydrothermal field are that the Lucky Strike area presents potential hydroid prey, and that nudibranchs apparently inhabit a lower activity area. It is hypothesized that the new species, which lacks eyes, is a permanent resident of vent fields on the Mid-Atlantic Ridge, but is probably not restricted to that environment.

  1. Granular chitin in the epidermis of nudibranch molluscs.

    Science.gov (United States)

    Martin, Rainer; Hild, Sabine; Walther, Paul; Ploss, Kerstin; Boland, Wilhelm; Tomaschko, Karl-Heinz

    2007-12-01

    Chitin is usually found in stiff extracellular coatings typified by the arthropod exoskeleton, and is not associated with the soft, flexible mollusc skin. Here, we show, however, that chitin in nudibranch gastropods (Opisthobranchia, Mollusca) occurs as intracellular granules that fill the epidermal cells of the skin and the epithelial cells of the stomach. In response to nematocysts fired by tentacles of prey Cnidaria, the epidermal cells of eolid nudibranchs (Aeolidacea) release masses of chitin granules, which then form aggregates with the nematocyst tubules, having the effect of insulating the animal from the deleterious action of the Cnidaria tentacles. Granular chitin, while protecting the animal, does not interfere with the suppleness and flexibility of the skin, in contrast to the stiffness of chitin armor. The specialized epidermis enables nudibranchs to live with and feed on Cnidaria. PMID:18083970

  2. 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 incl

  3. Phylogenetic analysis of Thecosomata Blainville, 1824 (holoplanktonic opisthobranchia) using morphological and molecular data.

    Science.gov (United States)

    Corse, Emmanuel; Rampal, Jeannine; Cuoc, Corinne; Pech, Nicolas; Perez, Yvan; Gilles, André

    2013-01-01

    Thecosomata is a marine zooplankton group, which played an important role in the carbonate cycle in oceans due to their shell composition. So far, there is important discrepancy between the previous morphological-based taxonomies, and subsequently the evolutionary history of Thecosomata. In this study, the remarkable planktonic sampling of TARA Oceans expedition associated with a set of various other missions allowed us to assess the phylogenetic relationships of Thecosomata using morphological and molecular data (28 S and COI genes). The two gene trees showed incongruities (e.g. Hyalocylis, Cavolinia), and high congruence between morphological and 28S trees (e.g. monophyly of Euthecosomata). The monophyly of straight shell species led us to reviving the Orthoconcha, and the split of Limacinidae led us to the revival of Embolus inflata replacing Limacina inflata. The results also jeopardized the Euthecosomata families that are based on plesiomorphic character state as in the case for Creseidae which was not a monophyletic group. Divergence times were also estimated, and suggested that the evolutionary history of Thecosomata was characterized by four major diversifying events. By bringing the knowledge of palaeontology, we propose a new evolutionary scenario for which macro-evolution implying morphological innovations were rhythmed by climatic changes and associated species turn-over that spread from the Eocene to Miocene, and were shaped principally by predation and shell buoyancy. PMID:23593138

  4. Larval development and metamorphosis in Pleurobranchaea maculata, with a review of development in the notaspidea (Opisthobranchia).

    Science.gov (United States)

    Gibson, Glenys D

    2003-10-01

    Pleurobranchaea maculata is a carnivorous notaspidean that is common in New Zealand. This species produces small eggs (diameter 100 microm) and planktotrophic veligers that hatch in 8 d and are planktonic for 3 weeks before settling on biofilmed surfaces (14 degrees C). Larval development is known in detail for only two other notaspidean species, P. japonica and Berthellina citrina. In all three species of pleurobranchids, mantle and shell growth show striking differences from veligers of other opisthobranch taxa. In young veligers of pleurobranchids, the shell is overgrown by the mantle, new shell is added by cells other than those of the mantle fold, and an operculum does not form. Thus some "adult" traits (e.g., notum differentiation, mechanism of shell growth, lack of operculum) are expressed early in larval development. This suggests that apomorphies characteristic of adult pleurobranchids evolved through heterochrony, with expression in larvae of traits typical of adults of other clades. The protoconch is dissolved post-settlement and not cast off as occurs in other opisthobranch orders, indicating that shell loss is apomorphic. P. maculata veligers are atypical of opisthobranchs in having a field of highly folded cells on the lower velar surface, a mouth that is posterior to the metatroch, and a richly glandular, possibly chemodefensive mantle. These data indicate that notaspidean larvae are highly derived in terms of the novel traits and the timing of morphogenic events. Phylogenetic analysis must consider embryological origins before assuming homology, as morphological similarities (e.g., shell loss) may have developed through distinct mechanisms. PMID:14583510

  5. Cytochemical localisation of lysosomal enzymes and acidic mucopolysaccharides in the salivary glands of Aplysia depilans (Opisthobranchia).

    Science.gov (United States)

    Lobo-da-Cunha, A

    2002-04-01

    Three types of secretory cells were reported in the salivary glands of Aplysia depilans: granular cells, vacuolated cells and mucocytes. To improve the characterisation of these cells, cytochemical methods for the detection of lysosomal enzymes and acidic mucopolysaccharides were applied. In granular cells, acid phosphatase and arylsulphatase were present in small lysosomes and in some secretory granules. The secretory granules could have received these enzymes after fusion with the small lysosomes that were frequently found very close to them. These cells were not stained with colloidal iron because they do not contain acidic mucopolysaccharides. In vacuolated cells, acid phosphatase and arylsulphatase were detected in lysosomes but not in the secretory vacuoles. Colloidal iron staining revealed the presence of acidic mucopolysaccharides in the vacuoles and in the Golgi apparatus of these cells. In mucocytes, lysosomes were very rare, but the secretion of these cells was very rich in acidic mucopolysaccharides. The filamentous network within the secretory vesicles was completely covered with iron particles, but practically no particles were observed over the granular masses attached to the membrane of the vesicles. Iron particles were also found in the trans-face cisternae of the U-shaped Golgi stacks, but were not seen in the cis-face cisternae or in the rough endoplasmic reticulum. PMID:12117284

  6. COMPARISON OF BIOCHEMICAL COMPOSITION AND DEVELOPMENTAL MODE IN TWO POPULATIONS OF COSTASIELLA [OPISTHOBRANCHIA: ASCOGLOSSA (= SACOGLOSSA)].

    Science.gov (United States)

    Miles, CECELIA M.; Clark, KERRY B.

    2002-05-01

    Egg masses of two populations of the ascoglossan Costasiella with different developmental modes were examined. Costasiella ocellifera is an encapsulated developer; Costasiella sp. has an obligate plankto-trophic larval stage. Adults of the two populations were also separable by habitat, but could not be distinguished by external morphology. Comparison of capsule diameters and calorimetric analyses showed that C. ocellifera eggs have nearly eight times the capsule volume and 10 times the calories of eggs of its congener. Histochemical examination of extra-embryonic intra-capsular vesicles of C. ocellifera revealed the contents to be glycoprotein. No inclusions were visible in the capsular fluid of Costasiella sp. Egg masses from the two populations differed significantly in the amount of TCA-soluble carbohydrate, lipid, and NaOH-soluble protein per egg and per milligram dry weight of egg mass. These components were, however, similar when expressed on an ash-free dry-weight basis. The advantage of hatching directly onto a suitable food source that is temporally persistent, but patchily distributed might have provided the selective pressure to achieve extended intra-capsular development in C. ocellifera. PMID:12011236

  7. Occurrence of the alien sea hare Aplysia dactylomela Rang, 1828 (Opisthobranchia, Aplysiidae in Malta

    Directory of Open Access Journals (Sweden)

    P.J. SCHEMBRI

    2012-12-01

    Full Text Available The alien sea hare Aplysia dactylomela, which is already established in several localities in the centraland eastern Mediterranean, is recorded for the first time from Malta on the basis of a specimen photographedat Cirkewwa (northern Malta. It is hypothesised that the occurrence of this species in Malta isa recent event and may be due to range expansion of the species.

  8. Phylogenetic analysis of Thecosomata Blainville, 1824 (holoplanktonic opisthobranchia using morphological and molecular data.

    Directory of Open Access Journals (Sweden)

    Emmanuel Corse

    Full Text Available Thecosomata is a marine zooplankton group, which played an important role in the carbonate cycle in oceans due to their shell composition. So far, there is important discrepancy between the previous morphological-based taxonomies, and subsequently the evolutionary history of Thecosomata. In this study, the remarkable planktonic sampling of TARA Oceans expedition associated with a set of various other missions allowed us to assess the phylogenetic relationships of Thecosomata using morphological and molecular data (28 S and COI genes. The two gene trees showed incongruities (e.g. Hyalocylis, Cavolinia, and high congruence between morphological and 28S trees (e.g. monophyly of Euthecosomata. The monophyly of straight shell species led us to reviving the Orthoconcha, and the split of Limacinidae led us to the revival of Embolus inflata replacing Limacina inflata. The results also jeopardized the Euthecosomata families that are based on plesiomorphic character state as in the case for Creseidae which was not a monophyletic group. Divergence times were also estimated, and suggested that the evolutionary history of Thecosomata was characterized by four major diversifying events. By bringing the knowledge of palaeontology, we propose a new evolutionary scenario for which macro-evolution implying morphological innovations were rhythmed by climatic changes and associated species turn-over that spread from the Eocene to Miocene, and were shaped principally by predation and shell buoyancy.

  9. Morphology, anatomy and histology of Doto uva Marcus, 1955 (Opisthobranchia: Nudibranchia) from the Chilean coast

    NARCIS (Netherlands)

    Fischer, M.A.; Velde, van der G.; Roubos, E.W.

    2006-01-01

    Doto uva Marcus, 1955 is a nudibranch species recorded from the Brazilian and Chilean coast. In spite of its wide distribution, D. uva has been described only superficially, mainly as to the pattern of its coloration, external morphology, radular teeth and reproductive system. Here we substantially

  10. Occurrence of the alien nudibranch Melibe viridis (Kelaart, 1858 (Opisthobranchia, Tethydidae, in the Maltese Islands

    Directory of Open Access Journals (Sweden)

    J.A. BORG

    2012-12-01

    Full Text Available The alien dendronotacean nudibranch Melibe viridis (Kelaart, 1858, a tropical Indo-Pacific species that seems to have been introduced by shipping into the Mediterranean via the Suez Canal, and which has established populations in Greece, Turkey, Cyprus, Montenegro, Croatia, NW Sicily, southern peninsular Italy and Djerba Island in the Gulf of Gabes, is recorded for the first time from Malta. A thriving population was observed on a soft sediment bottom at a depth of 18-20 m off the western coast of the island of Comino (Maltese Islands. It is suggested that this species was introduced into Malta due to a natural range expansion of surrounding populations.

  11. Distribution of molluscan remains in the sediment of the Chukchi Sea and its vicinity, the Arctic

    Institute of Scientific and Technical Information of China (English)

    Gao Aiguo; Xu Fengshan; Sun Haiqing; Li Lon

    2003-01-01

    The result of an analysis of mollusca remains collected from the Chukchi Sea, Beaufort Sea and Bering Sea in the First Chinese National Arctic Research Expedition, from July to September,1999 is presented. Seventeen species of mollusca have been identified, which belong to two classes: Bivalvia and Gastropoda. The compositions of the mollusca are very simple. According to the distribution pattern two groups may be distinguished among molluscan species. The Pan-Arctic and circumboreal group comprises Nuculana pernula, N. radiata, Nucula bellotii, Astarte montagui, Seripes groenlandicus, Macoma calcarea, M. moesta alaskana, Liocyma fluctuosa, Mya pseudoarenaria and Turritella polaris. Three species, Cyclocardia crebricos tata, Trichotrois coronata and Argobuccinum oregonense are components of the Pan-Arctic and Pacific boreal group. With regard to feeding habits, detritus feeders dominate. There are 7 species of detritus feeders, i.e. , Nuculana pernula, N. radiata,Nucula bellotii , Macoma calcarea , M. moesta alaskana , Macoma sp. and Trichotropis coronata . Detritus feeders are dominant with regard to the numbers of species as well as to the frequency of occurrence. Macoma calcarea is the most abundant species.

  12. First record of Planorbis planorbis (Linnaeus) naturally infected with Xiphidiocercariae from Derna, Libya.

    Science.gov (United States)

    Kamel, E G; Kassem, H H

    1991-04-01

    A review of the literature shows that the fresh water snail Planorbis planorbis (Mollusca: Gastropoda) infected with Xiphidiocercariae has never been recorded in Derna, Libya. In the present paper the first record is made from Wadi Derna (= Darnah), East coast of Libya. The snail harbour Xiphidiocercariae, the percentage of infection during May, 1989, was found to be 7.3%. Morphological description of the snail Planorbis planorbis, Xiphidiocercariae is given in the present investigation. The snail possibly acts as an intermediate host of trematode species in Libya. Further studies are needed to investigate and to observe the exact type of trematode in which the fresh water snail P. planorbis acts as an intermediate host in the life-cycle and to determine the definitive host in Libya.

  13. The radular morphology of Nassariidae (Gastropoda:Caenogastropoda) from China

    Institute of Scientific and Technical Information of China (English)

    YANG Jingwen; ZHANG Suping

    2011-01-01

    The family Nassariidae includes a number of species that are distributed throughout the world.Each species has a characteristic shell shape,tooth shape,and behavior.However,the classification of species in this family of the Rhachiglossa is controversial.We describe the radulae of 22 species from China in detail using optical and scanning electron microscopy.These species are considered to be representatives of two subfamilies,two genera,and 10 subgenera.Our results suggest that the morphology of the central tooth and the pair of lateral teeth and the presence or absence of a pair of intermediate accessory lateral teeth could be used to distinguish among species.We found no support for the subgeneric differentiation of the species.However,the presence or absence of the intermediate lateral accessory plate was characteristic of species divisions.We noted sexual dimorphism in the shape of the teeth in some species,and considerable variability of the shape of teeth within a single species.Based on our results,the genus Nassarius cannot be split into subgenera using radula morphology.

  14. Variation in Cavolinia inflexa (Lesueur, 1813) (Gastropoda: Pteropoda: Euthecosomata)

    NARCIS (Netherlands)

    Spoel, van der S.; Pierrot-Bults, A.C.

    1998-01-01

    Cavolinia inflexa (Lesueur, 1813) proves not to be composed of subspecies or formae, or to show clinal variation. Maximum shell length varies between 4 and 7 mm, shell width between 2 and 4 mm, length/width ratio between 0.51 and 0.81. A geographic pattern in the occurrence of different length/width

  15. Variation in Cavolinia inflexa (Lesueur, 1813) (Gastropoda: Pteropoda: Euthecosomata)

    OpenAIRE

    Spoel, van der, S.; Pierrot-Bults, A.C.

    1998-01-01

    Cavolinia inflexa (Lesueur, 1813) proves not to be composed of subspecies or formae, or to show clinal variation. Maximum shell length varies between 4 and 7 mm, shell width between 2 and 4 mm, length/width ratio between 0.51 and 0.81. A geographic pattern in the occurrence of different length/width ratios, on which the subdivision of this species was always based in literature, could not be found. Frequency analyses of length for all samples combined did not show subdivision in local populat...

  16. The phylogeny and systematics of the Nassariidae revisited (Gastropoda, Buccinoidea).

    Science.gov (United States)

    Galindo, Lee Ann; Puillandre, Nicolas; Utge, José; Lozouet, Pierre; Bouchet, Philippe

    2016-06-01

    Nassariidae are a group of scavenging, predominantly marine, snails that are diversified on soft bottoms as well as on rocky shores, and are the subject of numerous research papers in ecology, ecotoxicology or paleontology. A weak and/or apparently continuous variation in shell characters has resulted in an intimidating taxonomy, with complex synonymy lists. Over 1320 extant nominal species have been described, of which 442 are currently regarded as valid. Above species level, the state of the art is equally hazy, with four subfamilies and twelve genera currently accepted, and many other names in the graveyard of synonymy. A molecular analysis based on three mitochondrial (COI, 16S, 12S) and two nuclear (28S, H3) markers was conducted. Our dataset includes 218 putative nassariid species, comprising 9 of the 12 valid genera, and 25 nominal genera represented by their type species. The monophyly of the Nassariidae as classically construed is not confirmed. Species of Antillophos, Engoniophos, Phos, Nassaria, Tomlinia and Anentome (formerly considered Buccinidae) are included inside the Nassariidae clade. Within the Nassariinae, the tree unexpectedly demonstrates that species from the Atlantic and the Indo-Pacific form different clades which represent several independent diversification events. Through an integrative approach, the reconstruction of ancestral states was addressed for eight characters supposedly informative for taxonomy. Using numerous fossil calibration points, Nassariidae appear to have originated 120 MYA ago in Atlantic temperate waters during the Lower Cretaceous. Our results have a profound impact on nassariid taxonomy, especially with regard to the validity of subfamily- and genus-level names. PMID:27012605

  17. La familia Acmaeidae (Gastropoda, Archaeogastropoda en el Perú

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    Carlos Paredes

    2014-06-01

    Full Text Available Se reportan siete especies de la familia Acmaeidae de la zona litoral rocosa del Departamento de Lima: Scurria viridula (Lamarck, S. parasitica (Orbigny, S. variabilis (Sowerby, S. zebrina (Lesson, Collisella orbignyi (Dall, C. ceciliana (Orbigny y C. araucana (Orbigny. Se amplía el límite norte de la distribución geográfica de las dos últimas especies y asimismo para S. zebrina y S. parasitica. Se informa sobre la zonación vertical de las especies, su dominancia relativa y otras observaciones ecológicas. De la revisión de la literatura y los resultados del presente estudio se concluye que, conjuntamente con Scurria scurra (Lesson, 1830, son ocho las especies de Acmaeidae presentes en la Provincia Peruana.

  18. New species of Cyclodontina from Bahia, Brazil (Gastropoda, Pulmonata, Odontostomidae

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    Rodrigo B. Salvador

    2014-12-01

    Full Text Available A new species of pulmonate snail was recently collected in a small forest fragment in the city of Bom Jesus da Lapa, Bahia state, Brazil. Bahia is known for a high diversity of land snails and Bom Jesus da Lapa is an interesting locality, since it is close to the interface between two major Brazilian biomes: Cerrado and Caatinga. The new species is described as Cyclodontina tapuia sp. nov. and can be easily identified by its brown shell, conical spire, convex whorls, a sculpture comprised of strong ribs, and an aperture with four barriers: a median parietal tooth, a median palatal tooth, a median basal tooth and a strong columellar lamella. This discovery is also a reminder of how little the Brazilian continental molluscan fauna is known and of the urgency in studying and preserving the rich (though usually overlooked fauna of the Caatinga.

  19. Distribution of the Strombus gibberulus complex in Indonesia (Gastropoda, Strombidae)

    NARCIS (Netherlands)

    Coomans, Henry E.; Amsterdam, van Mieke L.M.

    1970-01-01

    Strombus gibberulus gibberulus L. is living in Indonesia at the western coast of Sumatra from Sabang to the Straits Sunda, and via the Straits in the Java Sea as far as Djakarta Bay. In all the rest of the Indonesian Archipelago the subspecies gibbosus (Röding) is found. The differences between gibb

  20. The complete mitochondrial genome of Babylonia borneensis (Gastropoda: Neogastropoda: Buccinidae).

    Science.gov (United States)

    Sung, Chia-Hsuan; Tseng, Chen-Te; Wang, Liang-Jong; Li, Yu-Chi; Lu, Jenn-Kan

    2016-09-01

    The complete mitochondrial genome sequence of the Babylonia borneensis is reported for the first time in this study. The length of genome was 15 556 bp, including 13 protein-coding genes, 2 ribosomal RNA genes and 22 transfer RNA genes. The nucleotide composition of the mitogenome showed AT-rich feature, with the AT content of 68.2%. Comparison of the identity of the B. borneensis mitogenome with B. areolata, B. lani and B. lutosa was 87.5%, 87.4% and 86.9%, respectively. The construction of phylogenetic tree showed high bootstrap support value. Babylonia borneensis grouped together with other Babylons and the lineages of Buccinidae was strongly supported. In this study, our results could provide a further understanding in the phylogenetic relationships of the Neogastropoda. PMID:27158871

  1. Helicopsis persica n. sp. from northern Iran (Gastropoda: Geomitridae).

    Science.gov (United States)

    Hausdorf, Bernhard; Bössneck, Ulrich

    2016-01-01

    Helicopsis Fitzinger, 1833 is a mainly eastern European genus of the xerophilous Helicellinae (Geomitridae, Helicoidea; for family systematics see Razkin et al. 2015) that is characterized by two symmetrical dart and accessory sacs. This is probably the plesiomorphous character state within the Geomitridae and Hygromiidae. Therefore, the delimitation and relationships of Helicopsis remained questionable (Hausdorf 1996). Most Helicopsis species are characterized by a lateral attachment of the outer layer of the penial papilla at the penis wall so that a cavity is separated in the proximal part of the penis (Schileyko 1978; Giusti et al. 1992; Hausdorf 1996). However, a similar cavity is present in some other Helicellinae (e.g., Pseudoxerophila, Xerolenta, Xeromunda). Giusti et al. (1992) considered these cavities artefacts, but it cannot be excluded that they are actually homologous to the cavity of Helicopsis. Therefore, it is doubtful whether such a cavity can be considered as an autapomorphy of Helicopsis. About ten species of Helicopsis are spread from Turkey and Bulgaria to the Ukraine with a centre of diversity on the Crimean peninsula. Only the type species, Helicopsis striata (Müller, 1774) is more widespread from Alsace in the west, the island Öland in the Baltic Sea in the north to Bulgaria and Turkey in the south and western Russia in the east. Furthermore, species from Morocco, Greece, Cyprus, Iran and the Kopetdag were classified as Helicopsis. The relationships between these species have to be examined in more detail. Here we describe a new Helicopsis species from Iran. PMID:27395547

  2. Transferência do gênero monotípico Parodizia Medina de Bithyniidae (Gastropoda, Prosobranchia para Pyramidellidae (Gastropoda, Heterobranchia Transference of the monotypic genus Parodizia Medina from Bithyniidae Gray (Gastropoda, Prosobranchia to Pyramidellidae Gray (Gastropoda, Heterobranchia

    Directory of Open Access Journals (Sweden)

    Maria Cristina Pons da Silva

    2004-06-01

    Full Text Available Propõe-se a transferência do gênero monitípico Parodizia Medina, 1959 de Bithyniidae (Prosobranchia para Pyramidellidae (Heterobranchia. A proposta está baseada em dados morfológicos de espécimens de P. uruguayensis Medina, 1959 procedentes da bacia do rio Tramandaí, Rio Grande do Sul, Brasil.The transference of the monotypic genus Parodizia Medina, 1959 from Bithyniidae (Prosobranchia to Pyramidellidae (Heterobranchia is proposed. The proposal is based on some morphological data of P. uruguayensis Medina, 1959 from Tramandaí river basin, Rio Grande do Sul, Brazil.

  3. The phylogeography of Indoplanorbis exustus (Gastropoda: Planorbidae in Asia

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    Diaz Jose L

    2010-07-01

    Full Text Available Abstract Background The freshwater snail Indoplanorbis exustus is found across India, Southeast Asia, central Asia (Afghanistan, Arabia and Africa. Indoplanorbis is of economic importance in that it is responsible for the transmission of several species of the genus Schistosoma which infect cattle and cause reduced livestock productivity. The snail is also of medical importance as a source of cercarial dermatitis among rural workers, particularly in India. In spite of its long history and wide geographical range, it is thought that Indoplanorbis includes only a single species. The aims of the present study were to date the radiation of Indoplanorbis across Asia so that the factors involved in its dispersal in the region could be tested, to reveal potential historical biogeographical events shaping the phylogeny of the snail, and to look for signs that I. exustus might be polyphyletic. Results The results indicated a radiation beginning in the late Miocene with a divergence of an ancestral bulinine lineage into Assam and peninsular India clades. A Southeast Asian clade diverged from the peninsular India clade late-Pliocene; this clade then radiated at a much more rapid pace to colonize all of the sampled range of Indoplanorbis in the mid-Pleistocene. Conclusions The phylogenetic depth of divergences between the Indian clades and Southeast Asian clades, together with habitat and parasitological differences suggest that I. exustus may comprise more than one species. The timescale estimated for the radiation suggests that the dispersal to Arabia and to Southeast Asia was facilitated by palaeogeographical events and climate change, and did not require human involvement. Further samples from Afghanistan, Africa and western India are required to refine the phylogeographical hypothesis and to include the African Recent dispersal.

  4. On a new Andinia (Gastropoda, Clausiliidae) from Peru

    NARCIS (Netherlands)

    Loosjes, F.E.

    1957-01-01

    Some time ago Prof. Dr. W. Weyrauch at Lima, Peru, sent to me specimens of a species of the subfamily Neniinae that proved to be new to science. Already about 70 species of the subfamily have become known from Peru, for an important part discovered by Prof. Weyrauch himself. Andinia (Ehrmanniella) f

  5. Some Anatomical, systematical and Geographical data on Neniinae (Gastropoda, Clausiliidae)

    NARCIS (Netherlands)

    Loosjes, F.A.; Loosjes-van Bemmel, A.C.W.

    1966-01-01

    I. INTRODUCTION Up to the moment more than one hundred species and subspecies of Neniinae are known from Central and South America. They are incorporated into 22 genera and subgenera, almost exclusively based on characters of the shells. Only little is known of the anatomy of the animals (Binney, 18

  6. Hydrocarbons in the land snail Cepaea nemoralis (L.) (gastropoda, pulmonata)

    NARCIS (Netherlands)

    Horst, D.J. van der; Oudejans, R.C.H.M.

    1972-01-01

    1. 1. The biosynthesis of hydrocarbons in the snail Cepaea nemoralis was studied after injection of the 14C-labelled precursors acetate, valine, isoleucine and palmitic acid. 2. 2. The highest incorporation was achieved with palmitic acid, although with the other precursors the hydrocarbons were al

  7. Benthic Macro-Fauna Composition and Abundance in Sombreiro River, Niger Delta, Nigeria

    Directory of Open Access Journals (Sweden)

    E.N. Ezekiel

    2011-04-01

    Full Text Available The benthic macro-fauna composition and abundance in sombreiro was studied for a period of two years (August 2007 - July2009. A total of twenty-eight species belonging to fourteen (14 families, six (6 classes and three (3 phyla were recorded in Sombreiro River. The phylum Annelida dominated with two classes (Oligochaeta and Polychaeta. Oligochaeta was represented by two families (Naididae and Lumbricidae and seven species having 25% by composition. Polychaeta was represented by seven families (Nereidae, Nepthyidae, Capitellidae, Eucinidae, Glyceridae, Arenicolidae and Syllidae and thirteen species having 46.4% by composition. The Phylum arthropoda was represented by two classes (Crustacea and inseita. Two families (Gammaridae and Penaidae having two species consisting of 7.2% were recorded, for the class crustacea. The class insecta was represented by one family (Chironomidae with one species consisting of 3.6%. The phylum Mollusca was represented by two classes (Gastropoda and Bivalvia. Gastropoda had two species with 7.2% composition and Bivalvia has three species with10.7% composition. Oligochaeta was the highest and constituted 62.0%. The others were Polychaeta (23.9%, Insecta (6.7%, Gastropoda (3.9%, Bivalvia (2.2% and Crustacea (1.3%. The mean diversity(S ranged between 11 species. Mean abundance of individuals (N was 985. Mean Margalef index (d value was 1.339. The mean value for Shannon-Wienner (H was 0.956. Mean Pielou’s index of relative density or evenness index (E was 0.986. Mean SimpsIn’s Dominance index (C was 0.623.

  8. Localization of GABA-like immunoreactivity in the central nervous system of Aplysia californica.

    Science.gov (United States)

    Díaz-Ríos, M; Suess, E; Miller, M W

    1999-10-18

    Gamma-aminobutyric acid (GABA) is present in the central nervous system of Aplysia californica (Gastropoda, Opisthobranchia) where its role as a neurotransmitter is supported by pharmacological, biochemical, and anatomical investigations. In this study, the distribution of GABA-immunoreactive (GABAi) neurons and fiber systems in Aplysia was examined by using wholemount immunohistochemistry and nerve backfill methods. GABAi neurons were located in the buccal, cerebral, and pedal ganglia. Major commissural fiber systems were present in each of these ganglia, whereas more limited fiber systems were observed in the ganglionic connectives. Some of the interganglionic fibers were found to originate from two unpaired GABAi neurons, one in the buccal ganglion and one in the right pedal ganglion, each of which exhibited bilateral projections. No GABAi fibers were found in the nerves that innervate peripheral sensory, motor, or visceral organs. Although GABAi cells were not observed in the pleural or abdominal ganglia, these ganglia did receive limited projections of GABAi fibers originating from neurons in the pedal ganglia. The distribution of GABAi neurons suggests that this transmitter system may be primarily involved in coordinating certain bilateral central pattern generator (CPG) systems related to feeding and locomotion. In addition, the presence of specific interganglionic GABAi projections also suggests a role in the regulation or coordination of circuits that produce components of complex behaviors. PMID:10524338

  9. Morphology, taxonomic status and distribution of the opisthobranch mollusc Coryphella (s.l.) japonica from the central deep water basin of the Sea of Japan

    Science.gov (United States)

    Martynov, Alexander V.

    2013-02-01

    The opisthobranch fauna (Gastropoda: Opisthobranchia) of the deep sea basins of the Sea of Japan is reviewed. A detailed description of the most common deep sea nudibranch species Coryphella japonicaVolodchenko, 1941 is given based on materials from various expeditions (including R/V "Vityaz" cruises and SoJaBio project). Distinct morphological features of C. japonica are discussed and its valid taxonomic status is confirmed. The considerable radular variability of C. japonica for the first time is documented using a scanning electron microscope. Unique features of the bathymetric distribution of C. japonica ranging from shelf to the abyssal depths are discussed in connection with the "pseudabyssal area" concept. C. japonica was compared to its assumed synonym C. salmonacea, and to similar C. athadona. Material from all these species, including types of C. japonica, was examined externally, anatomically via dissection, and SEM. C. salmonacea is restricted to North Atlantic and Arctic only, whereas C. japonica inhabits NE Pacific including deep water basins of the Sea of Japan.

  10. Host shift and speciation in a coral-feeding nudibranch.

    Science.gov (United States)

    Faucci, Anuschka; Toonen, Robert J; Hadfield, Michael G

    2007-01-01

    While the role of host preference in ecological speciation has been investigated extensively in terrestrial systems, very little is known in marine environments. Host preference combined with mate choice on the preferred host can lead to population subdivision and adaptation leading to host shifts. We use a phylogenetic approach based on two mitochondrial genetic markers to disentangle the taxonomic status and to investigate the role of host specificity in the speciation of the nudibranch genus Phestilla (Gastropoda, Opisthobranchia) from Guam, Palau and Hawaii. Species of the genus Phestilla complete their life cycle almost entirely on their specific host coral (species of Porites, Goniopora and Tubastrea). They reproduce on their host coral and their planktonic larvae require a host-specific chemical cue to metamorphose and settle onto their host. The phylogenetic trees of the combined cytochrome oxidase I and ribosomal 16S gene sequences clarify the relationship among species of Phestilla identifying most of the nominal species as monophyletic clades. We found a possible case of host shift from Porites to Goniopora and Tubastrea in sympatric Phestilla spp. This represents one of the first documented cases of host shift as a mechanism underlying speciation in a marine invertebrate. Furthermore, we found highly divergent clades within Phestilla sp. 1 and Phestilla minor (8.1-11.1%), suggesting cryptic speciation. The presence of a strong phylogenetic signal for the coral host confirms that the tight link between species of Phestilla and their host coral probably played an important role in speciation within this genus. PMID:17134995

  11. Serotonin-like immunoreactivity in the central and peripheral nervous systems of the interstitial acochlidean Asperspina sp. (Opisthobranchia).

    Science.gov (United States)

    Hochberg, Rick

    2007-08-01

    Species of Acochlidea are common members of the marine interstitial environment and defined in part by their minuscule size and highly divergent morphology relative to other benthic opisthobranchs. Despite these differences, acochlideans such as species of Asperspina display many plesiomorphic characteristics, including an unfused condition of their neural ganglia. To gain insight into the distribution of specific neural subsets within acochlidean ganglia, a species of Asperspina was studied by using anti-serotonin immunohistochemistry and epifluorescence and confocal laser scanning microscopy. Results reveal similarities between Asperspina and larger opisthobranchs in the general distribution of serotonergic perikarya in the central nervous system. Specifically, the arrangement of perikarya into regional clusters within the cerebral and pedal ganglia and the absence of immunoreactive perikarya in the pleural ganglia are similar to the model species of Aplysia californica, Pleurobranchaea californica, and Tritonia diomedea. Moreover, serotonergic innervation of the rhinophores in all opisthobranchs, including Asperspina sp., originates from the cerebral ganglion instead of directly from the rhinophoral ganglion. Serotonergic innervation of the body wall, including the epithelium, muscles, and pedal sole, appears to arise exclusively from pedal and accessory ganglia. These observations indicate a general conservation of serotonin-like immunoreactivity in the central and peripheral nervous systems of acochlidean and other benthic opisthobranchs. PMID:17679719

  12. Optimal salinity and temperature intervals of Limapontia capitata (Opisthobranchia, Sacoglossa) determined by growth and heart rate measurements

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, K.

    1977-12-01

    Growth rate of Limapontia capitata was determined at various temperatures and salinities. An optimal temperature of about 15/sup 0/C was found on the basis of growth rate, percentage of nongrowing animals during the experiments, spawning, and heart rate measurements. Q/sub 10/ of heart rates shows a high value in the temperature interval immediately preceding maximum heart rate. This indicates a marked increase in respiration without a corresponding increase in growth. Heat coma sets in at 38-40/sup 0/C, and cold coma is estimated to set in around 0/sup 0/C. In late summer and early autumn, when the experimental animals were collected, the estimated mean water temperature in the sampling area is about 15/sup 0/C. Based on the same factors as above (no heart rate measurements), an optimal salinity of about 30/sup 0///sub 00/ was determined. This is far from the mean of the sampling area (about 15%), and spawning is as abundant (or more so) at 20 and 15%, so some kind of adaption to salinity--although not with respect to growth--seems to exist. Death of osmotic stress only occurred at room temperature (20-23/sup 0/C) and a concurrent salinity of 5%.

  13. Mating behaviour in the sea slug Elysia timida (Opisthobranchia, Sacoglossa: hypodermic injection, sperm transfer and balanced reciprocity

    Directory of Open Access Journals (Sweden)

    Anthes Nils

    2007-07-01

    Full Text Available Abstract Background In simultaneous hermaphrodites with copulation and internal fertilization it is often unclear whether reciprocal sperm exchange results from the unconditional willingness of both partners to donate and receive sperm, or whether it follows from a more controlled process such as conditional reciprocal sperm exchange, i.e. sperm trading. While in some sea slugs mating is assumed to be based on sperm trading, it seems to be unconditional in others. Here, we describe the unusual mating behaviour of Elysia timida, a small sacoglossan, focussing on indications for conditional reciprocity. Results E. timida shows an as yet unique combination of a long series of hypodermic transfers followed by a short phase with standard insemination into a female genital aperture. Hypodermic transfer takes place in the form of repeated small injections into the dorsal surface of the partner, interrupted by synchronised circling movements. In the final mating phase sperm is transferred into the female genital aperture in a short period. In both phases the two mating individuals show a high degree of transfer symmetry and synchrony. While total duration and number of transfers were balanced within pairs, they varied significantly between pairs. Furthermore, looking at individual hypodermic transfers within pairs, reciprocal transfers lasted longer than unilateral transfers. Final sperm transfers were always reciprocal except for two cases which also diverted from the usual pattern in ways that were suggestive of a conflict over reciprocity. Conclusion Our results suggest that individual mating decisions in E. timida depend on what the partner does, indicating conditional reciprocity. If hypodermic transfers also involve the transfer of sperm (which remains to be confirmed, this system represents an up to now unique transition stage between hypodermic and standard insemination, both of which are widespread in this group of sea slugs, but never have been observed to co-occur within the same species.

  14. DIETARY NITROGEN AVAILABILITY IN MACROALGAE AFFECTS GROWTH OF THE SEA HARE APLYSIA CALIFORNICA (OPISTHOBRANCHIA:ANASPIDEA). (R830414)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  15. Morphology, anatomy and histology of a new species of Flabellina Voigt, 1834 (Opisthobranchia: Aeolidoidea) from the Chilean coast

    NARCIS (Netherlands)

    Fischer, M.A.; Velde, G. van der; Roubos, E.W.

    2007-01-01

    Flabellina cerverai sp. nov. was found in Bay La Herradura, Coquimbo, North of Chile, and clearly differs from other members of the Flabellinidae by the following combination of main characters: (1) small body size (4.5–6.3 mm), (2) translucent-yellow body coloration, with a white line along the dor

  16. 上海苏州河大型底栖动物的研究%A study on macro-invertebrate of the Suzhou River, Shanghai.

    Institute of Scientific and Technical Information of China (English)

    刘国才; 赖伟; 殷浩文; 顾福康

    2001-01-01

    苏州河白鹤至浙江路段6个采样断面大型底栖动物隶属于环节动物门(Annelida)、软体动物门(Mollusca)及节肢动物门(Arthropoda).其中寡毛纲(Oligochaeta)4种、蛭纲(Hirudinea)2种、腹足纲(Gastropoda)5种、双壳纲(Bivalvia)2种及昆虫纲摇蚊科幼虫(Chironomidae)与潜蝇蛹(Agromyzigae)(未定种).随着底质污染的加重,群落结构趋于简化.种类少、高度耐污是存活大型底栖动物的显著特点.从白鹤至华槽断面,高度耐污的霍甫水丝蚓(Limnodrilus hoffmeisteri)数量趋于增加,并在华槽断面形成明显数量高峰;北新泾、武宁路河段底质污染严重,环节动物、软体动物消失;浙江路断面受黄浦江"逆流"影响,寡毛纲动物再度出现,并形成一定数量.%Macro-invertebrate from Annelida, Mollusca and Arthropoda were found in six sections from Baihe to Zhejiang road in the Suzhou River, among which four species were from Oligochaeta, two species from Hirudinea, five species from Gastropoda, two species from Bivalvia and several species from Insecta (unidentified). The community structure of macro-invertebrates became simple with the sediment pollution getting heavier. Limited species with high pollution resistibility were the characteristics of the species survival. The amounts of Limnodrilus hoffmeisteri with high pollution resistibility increased gradually from Baihe to Huacao section, and reached a peak in Huacao section; species from An-nelida, Mollusca were not found in Beixinjing and Wuninglu sections due to heavy sediment pollution; species from Oli-gochaeta were found again and had certain numbers in Zhejiang road section as the result of the effect of courterflow of the Huangpu River.

  17. 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.

  18. First molecular phylogeny of the subfamily Polycerinae (Mollusca, Nudibranchia, Polyceridae)

    Science.gov (United States)

    Palomar, Gemma; Pola, Marta; Garcia-Vazquez, Eva

    2014-03-01

    The subfamily Polycerinae includes four genera with around 46 species described to date. This subfamily is characterized by a limaciform body, which may have simple tentacular processes on the margin of the oral veil. Phylogenetic relationships between the genera of the subfamily Polycerinae (Polyceridae) have not yet been studied, and therefore, the only available information is based on morphological descriptions. The present study reports the first phylogenetic analysis of Polycerinae based on the mitochondrial genes cytochrome oxidase subunit I and the large ribosomal subunit (16S rRNA) using maximum likelihood and Bayesian methods. Our results showed that Polycerinae is monophyletic, but the relationships within the subfamily as well as within Polycera remain unresolved. A key finding of this study is that there are clearly two sympatric species of Polycera present in South Africa: Polycera capensis Quoy and Gaimard, 1824 also found in Australia and an undescribed Polycera sp. On the other hand, the studied specimens of the genus Gymnodoris were clustered within Polycerinae, reopening the problem of the systematic position of this genus. Additional genes and species of Polycerinae and Gymnodoris would provide more information and probably fully resolve this situation.

  19. Sublethal foot-predation on Donacidae (Mollusca: Bivalvia)

    Science.gov (United States)

    Salas, Carmen; Tirado, Cristina; Manjón-Cabeza, Maria Eugenia

    2001-08-01

    The incidence of foot nipping was studied on the Donax spp. of the littoral of Málaga (Southern Spain, 2875 specimens collected from February 1990 to January 1991) and of Ré island (French Atlantic coast, 262 specimens of Donax vittatus (Da Costa, 1778) collected in May 1996). In Málaga, Donax trunculus L., 1758 was the species most regularly nipped (18% of individuals), with peaks in summer (25% in August and 48% in September) and winter (34% in December). In Ré island, 27% of the specimens showed a nipped foot. Logistic regression shows that in D. trunculus length is the variable that most influences the probability of foot nipping, followed by weight and chlorophyll a. However, the difference in length between damaged and undamaged individuals was not significant (U-Mann-Whitney test). The size class frequency and the values of Ivlev's index show that the small size classes were avoided, while for the other size classes predation remained balanced throughout the year. Therefore, the avoidance of the small size classes makes length the most influential variable. The logistic regression indicated a coefficient B=-0.03 for weight. This implies a slightly negative influence on the probability of foot nipping. However, without the data of September, there is a positive correlation ( r=0.76, p<0.01) between the monthly percentages of predation and the flesh dry weight of a standard individual (25 mm long). The peak in September could be due to the recruitment peak of bivalves, which may have attracted more predators to the area, and/or to the recruitment of predators such as crabs to the swash zone. Logistic regression and test of comparison of percentages indicate that there was not any influence of the sex of an animal on the probability of foot nipping. Only in February was a significantly higher percentage ( p<0.05) of females nipped (44.44%) than the total of females in the sample (20.20%). The biomass (as flesh dry weight) of D. trunculus lost by foot nipping amounts to more than 20% in most of the size classes. There was an increase from the small sizes to the largest ones, in which it reaches 37%, with a positive correlation ( r=0.84; p<0.005) between size class and loss of biomass. Possible predators responsible for the foot nipping are crabs. Crab species usually found together with the donacids were Portumnus latipes (Pennant, 1777) Liocarcinus vernalis (Risso, 1816) and Atelecyclus undecimdentatus (Herbst, 1783). In aquarium experiments, they demonstrated an ability to nip the foot of clams. Portumnus latipes was the most active foot nipper, but left alive all the damaged clams. Therefore, we conclude that crabs are the most likely foot-nipping predators in the field.

  20. Late Neogene, Seismic stratigraphy, Biostratigraphy, Mollusca, Evolution, Pannonian basin

    OpenAIRE

    Velić, I.; Durn, G.

    1993-01-01

    The combined use of seismic stratigraphy and mollusc biostratigraphy in Late Neogene lacustrine deposits of the Pannonian basin offers three new approaches: First, the comparison of seismic facies and biofacies facilitates to make a distinction between biostratigraphic units and biofacies. Second, seismic datum levels permit crosschecking of discrete (magnetic, radiometric, and biostratigraphic) data, thus dating evolutionary events. Third, seismic monitoring of the sedimentary hi...

  1. New records of Protobranchia (Mollusca: Bivalvia in the Peruvian Sea

    Directory of Open Access Journals (Sweden)

    Carlos Paredes

    2014-06-01

    Full Text Available The following species of Bivalvia have been recorded for the first time for Peruvian waters: Nucula (Nucula iphigenia (Dall, 1908; Ennucula cardara (Dall, 1916; Nuculana (Nuculana extenuata (Dall, 1897; Orthoyoldia panamensis (Dall, 1908. These bivalves were collected in the platform and continental slope down to depths of 864 meters.

  2. Mollusca (terrestrial and marine Gastropods et Bivalvia from Morocco

    Directory of Open Access Journals (Sweden)

    Atanas Irikov

    2013-12-01

    Full Text Available Fifteen samples with molluscs are collected from various habitats and regions of Morocco, located in the seashore zone, as well as the central and the eastern parts of the country. We recorded 21 terrestrial and 15 marine species of molluscs. New localities and new species for the fauna of Morocco and the African continent are reported for the first time.

  3. Morphological and molecular diversity of Unionidae (Mollusca, Bivalvia from Portugal

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    Reis, J.

    2013-06-01

    Full Text Available Freshwater mussels from the family Unionidae are known to exhibit a high level of ecological phenotypic plasticity that is reflected in their shell shape. This variation has caused uncertainty on systematics and taxonomy of the group. Several naiad populations from nine river basins from Portugal were analyzed genetically, using two mitochondrial gene fragments (16SrRNA and Cytochrome Oxidase I and morphologically, using ANOVA analyses of shell dimmensions. Molecular phylogenetic analyses were used to revise the systematics and to infer an evolutionary hypothesis for the family at the western-most Atlantic Iberian Peninsula. Genetic and morphological data were in agreement and supported the occurrence of 5 species in the region: Anodonta anatina, Anodonta cygnea, Potomida littoralis, Unio tumidiformis and Unio delphinus. The differentiation of all these species, except A. cygnea, is thought to have taken place during the isolation of the Iberian Peninsula and formation of the current river basins in the Tertiary. The possibility of A. cygnea being a relatively recent introduction is discussed. Basic morphometric measures of the shell proved to be useful to separate Unio species, but also seem to be strongly affected by environmental conditions. The high intra-specific morphologic variation was partially related to the species’ high level of phenotypic plasticity, but seems to have an important role in evolutionary processes.Las náyades de la familia Unionidae tienen gran plasticidad fenotípica, lo que se refleja en la forma de su concha. Esta variabilidad morfológica ha sido causa de gran confusión en la taxonomía y sistemática del grupo. Se han estudiado, genética y morfológicamente, numerosas poblaciones de náyades provenientes de nueve cuencas hidrográficas portuguesas. Para ello se han analizando dos fragmentos de genes mitocondriales (ARNr 16S y Citocromo Oxidasa I así como diferentes variables morfológicas de la concha. Se han realizado además análisis filogenéticos para conocer la sistemática de la familia e inferir una hipótesis evolutiva de su distribución en el oeste de la península Ibérica. Los datos genéticos y morfológicos sugieren la existencia de cinco especies: Anodonta anatina, Anodonta cygnea, Potomida littoralis, Unio tumidiformis y Unio delphinus. La diferenciación de estas especies, con la excepción de A. cygnea, ha ocurrido durante el aislamiento de la península Ibérica y posterior formación de las actuales cuencas hidrográficas en el Terciario. Se discute la posibilidad de que la presencia de A. cygnea se deba a una introducción reciente. Los datos morfométricos analizados pueden ser útiles para separar las especies del género Unio, pero son también dependientes de las condiciones ambientales. La elevada variabilidad morfológica dentro de cada especie está relacionada con su plasticidad fenotípica, pero tiene a su vez un importante papel en el proceso evolutivo.

  4. Cleavage pattern and mesentoblast formation in Acanthochiton crinitus (Polyplacophora, Mollusca).

    Science.gov (United States)

    van den Biggelaar, J A

    1996-03-15

    In characteristic spiralian embryos the mesentoblast is the stem cell of the mesodermal bands. It is a derivative of the dorsal quadrant. At least in gastropod molluscs, the ancestral form for the specification of the dorsal quadrant out of four initially equal quadrants is by centralization of one of the four macromeres after the separation of the presumptive ecto- and entoblast cells. Then this macromere is induced by the animal micromeres to produce the mesentoblast. In this paper it is shown that in the embryo of the polyplacophoran Acanthochiton crinitus, specification of the dorsal quadrant and formation of the mesentoblast exactly follow the same pattern. After deletion of the first quartet of micromeres none of the macromeres is centralized, no mesentoblast is formed, and the embryo remains radially symmetrical. Apparently, the mechanism for the specification of the dorsal quadrant and the formation of the mesentoblast has been conserved during the evolution of the main molluscan taxa. It has been discussed whether this mechanism might be a plesiomorphous property, characteristic of less derived spiralian phyla. PMID:8631512

  5. Thermosensitivity during embryonic development of Lymnaea stagnalis (Mollusca)

    NARCIS (Netherlands)

    Boon-Niermeijer, E.K.; Scheur, H. van de

    1984-01-01

    1. 1.|The percentage of survival after 1 hr at 40.0°C is lowest at the larval trochophore stage and at hatching of the young snail. 2. 2.|Heat resistance depends on the stage of development. 3. 3.|From the early cleavage stage onwards a higher percentage of embryos can withstand high temperature a

  6. Different roles for homologous interneurons in species exhibiting similar rhythmic behaviors.

    Science.gov (United States)

    Sakurai, Akira; Newcomb, James M; Lillvis, Joshua L; Katz, Paul S

    2011-06-21

    It is often assumed that similar behaviors in related species are produced by similar neural mechanisms. To test this, we examined the neuronal basis of a simple swimming behavior in two nudibranchs (Mollusca, Opisthobranchia), Melibe leonina and Dendronotus iris. The side-to-side swimming movements of Dendronotus [1] strongly resemble those of Melibe [2, 3]. In Melibe, it was previously shown that the central pattern generator (CPG) for swimming is composed of two bilaterally symmetric pairs of identified interneurons, swim interneuron 1 (Si1) and swim interneuron 2 (Si2), which are electrically coupled ipsilaterally and mutually inhibit both contralateral counterparts [2, 4]. We identified homologs of Si1 and Si2 in Dendronotus. (Henceforth, homologous neurons in each species will be distinguished by the subscripts (Den) and (Mel).) We found that Si2(Den) and Si2(Mel) play similar roles in generating the swim motor pattern. However, unlike Si1(Mel), Si1(Den) was not part of the swim CPG, was not strongly coupled to the ipsilateral Si2(Den), and did not inhibit the contralateral neurons. Thus, species differences exist in the neuronal organization of the swim CPGs despite the similarity of the behaviors. Therefore, similarity in species-typical behavior is not necessarily predictive of common neural mechanisms, even for homologous neurons in closely related species. PMID:21620707

  7. Primer registro de Dondice parguerensis (Mollusca: Favorinidae para Venezuela First record of Dondice parguerensis (Mollusca: Favorinidae in Venezuela

    Directory of Open Access Journals (Sweden)

    Joany Mariño

    2011-06-01

    Full Text Available Se cita por primera vez para Venezuela el aeolidaceo Dondice parguerensis Brandon y Cutress, 1985, parásito de los cnidarios Cassiopea xamachana Bigelow, 1892 y Cassiopea frondosa (Pallas, 1774, hasta ahora sólo conocido de Puerto Rico, Panamá y Bermudas.The presence of the aeolidacean Dondice parguerensis Brandon and Cutress, 1985, parasite of the cnidaria Cassiopea xamachana Bigelow, 1892 and Cassiopea frondosa (Pallas, 1774 is recorded for the first time in Venezuela. It was previously recorded in Puerto Rico, Panama and Bermuda.

  8. ПОВЫШЕНИЕ ВИТАЛИТЕТА У БРЮХОНОГИХ МОЛЛЮСКОВ (GASTROPODA) В УСЛОВИЯХ НЕФТЯНОГО ЗАГРЯЗНЕНИЯ ПОСРЕДСТВОМ ВОЗДЕЙСТВИЯ ЭЛЕКТРОМАГНИТНЫМИ ПОЛЯМИ

    OpenAIRE

    Гордеева, Мария; Ильминских, Николай; Гашев, Сергей

    2011-01-01

    Исследовано стимулирующее воздействие электромагнитных полей на брюхоногих моллюсков (Gastropoda) в условиях нефтяного загрязнения (1,5 и 2 мг/л). Показаны повышение выживаемости моллюсков и кратное увеличение численности их потомства в сравнении с контролем, оценивается в целом как повышение виталитета. Рассматриваются механизмы токсикорезистентности....

  9. Packaging and delivery of chemical weapons: a defensive trojan horse stratagem in chromodorid nudibranchs.

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    Marianna Carbone

    Full Text Available BACKGROUND: Storage of secondary metabolites with a putative defensive role occurs in the so-called mantle dermal formations (MDFs that are located in the more exposed parts of the body of most and very likely all members of an entire family of marine mollusks, the chromodorid nudibranchs (Gastropoda: Opisthobranchia. Given that these structures usually lack a duct system, the mechanism for exudation of their contents remains unclear, as does their adaptive significance. One possible explanation could be that they are adapted so as to be preferentially attacked by predators. The nudibranchs might offer packages containing highly repugnant chemicals along with parts of their bodies to the predators, as a defensive variant of the strategic theme of the Trojan horse. METHODOLOGY AND PRINCIPAL FINDINGS: We detected, by quantitative (1H-NMR, extremely high local concentrations of secondary metabolites in the MDFs of six species belonging to five chromodorid genera. The compounds were purified by chromatographic methods and subsequently evaluated for their feeding deterrent properties, obtaining dose-response curves. We found that only distasteful compounds are accumulated in the reservoirs at concentrations that far exceed the values corresponding to maximum deterrent activity in the feeding assays. Other basic evidence, both field and experimental, has been acquired to elucidate the kind of damage that the predators can produce on both the nudibranchs' mantles and the MDFs. SIGNIFICANCE: As a result of a long evolutionary process that has progressively led to the accumulation of defensive chemical weapons in localized anatomical structures, the extant chromodorid nudibranchs remain in place when molested, retracting respiratory and chemosensory organs, but offering readily accessible parts of their body to predators. When these parts are masticated or wounded by predators, breakage of the MDFs results in the release of distasteful compounds at

  10. Bioactive molecules from sea hares.

    Science.gov (United States)

    Kamiya, H; Sakai, R; Jimbo, M

    2006-01-01

    Sea hares, belonging to the order Opisthobranchia, subclass Gastropoda, are mollusks that have attracted many researchers who are interested in the chemical defense mechanisms of these soft and "shell-less" snails. Numbers of small molecules of dietary origin have been isolated from sea hares and some have ecologically relevant activities, such as fish deterrent activity or toxicity. Recently, however, greater attention has been paid to biomedically interesting sea hare isolates such as dolastatins, a series of antitumor peptide/macrolides isolated from Dolabella auricularia. Another series of bioactive peptide/macrolides, as represented by aplyronines, have been isolated from sea hares in Japanese waters. Although earlier studies indicated the potent antitumor activity of aplyronines, their clinical development has never been conducted because of the minute amount of compound available from the natural source. Recent synthetic studies, however, have made it possible to prepare these compounds and analogs for a structure-activity relationship study, and started to uncover their unique action mechanism towards their putative targets, microfilaments. Here, recent findings of small antitumor molecules isolated from Japanese sea hares are reviewed. Sea hares are also known to produce cytotoxic and antimicrobial proteins. In contrast to the small molecules of dietary origin, proteins are the genetic products of sea hares and they are likely to have some primary physiological functions in addition to ecological roles in the sea hare. Based on the biochemical properties and phylogenetic analysis of these proteins, we propose that they belong to one family of molecule, the "Aplysianin A family," although their molecular weights are apparently divided into two groups. Interestingly, the active principles in Aplysia species and Dolabella auricularia were shown to be L-amino acid oxidase (LAAO), a flavin enzyme that oxidizes an alpha-amino group of the substrate with

  11. Gastropod arginine kinases from Cellana grata and Aplysia kurodai. Isolation and cDNA-derived amino acid sequences.

    Science.gov (United States)

    Suzuki, T; Inoue, N; Higashi, T; Mizobuchi, R; Sugimura, N; Yokouchi, K; Furukohri, T

    2000-12-01

    Arginine kinase (AK) was isolated from the radular muscle of the gastropod molluscs Cellana grata (subclass Prosobranchia) and Aplysia kurodai (subclass Opisthobranchia), respectively, by ammonium sulfate fractionation, Sephadex G-75 gel filtration and DEAE-ion exchange chromatography. The denatured relative molecular mass values were estimated to be 40 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isolated enzyme from Aplysia gave a Km value of 0.6 mM for arginine and a Vmax value of 13 micromole Pi min(-1) mg protein(-1) for the forward reaction. These values are comparable to other molluscan AKs. The cDNAs encoding Cellana and Aplysia AKs were amplified by polymerase chain reaction, and the nucleotide sequences of 1,608 and 1,239 bp, respectively, were determined. The open reading frame for Cellana AK is 1044 nucleotides in length and encodes a protein with 347 amino acid residues, and that for A. kurodai is 1077 nucleotides and 354 residues. The cDNA-derived amino acid sequences were validated by chemical sequencing of internal lysyl endopeptidase peptides. The amino acid sequences of Cellana and Aplysia AKs showed the highest percent identity (66-73%) with those of the abalone Nordotis and turbanshell Battilus belonging to the same class Gastropoda. These AK sequences still have a strong homology (63-71%) with that of the chiton Liolophura (class Polyplacophora), which is believed to be one of the most primitive molluscs. On the other hand, these AK sequences are less homologous (55-57%) with that of the clam Pseudocardium (class Bivalvia), suggesting that the biological position of the class Polyplacophora should be reconsidered. PMID:11281267

  12. Developmental analysis reveals labial and subradular ganglia and the primary framework of the nervous system in nudibranch gastropods.

    Science.gov (United States)

    Page, L R

    1993-11-01

    Previous ultrastructural observations on late stage larvae of dorid nudibranchs (Gastropoda, Opisthobranchia) revealed two pairs of ganglia within the base of the foot that do not have obvious counterparts in existing descriptions of other gastropod larvae [Chia and Koss (1989). Cell Tiss. Res. 256:17-26.] One of these ganglionic pairs has been implicated in the initiation of settlement preceding metamorphosis [Arkett et al. (1989). Biol. Bull. 176:155-160.] By examining neurogenesis in sequential larval stages, I have found that the pattern of connectives and commissures associated with these enigmatic ganglia is comparable to patterns found in less consolidated adult nervous systems of chitons, monoplacophorans, and archaeogastropods. These comparative data suggest that the two pairs of ganglia in dorid nudibranch larvae are homologues of labial and subradular ganglia. The labial ganglia become incorporated into the cerebral ganglia at metamorphosis. In an attempt to integrate anatomical and developmental observations with behavioral and neurophysiological results, I suggest that receptor cells of the larval labial ganglia may become postmetamorphic primary mechanoreceptors of the oral tube, which have central cell bodies within the "cerebral" ganglia and which help coordinate feeding. Results of this study also address a larger evolutionary issue by questioning the traditional model of an ancestral molluscan nervous system that consists of four longitudinal nerve cords that arise from separate sites along a circumesophageal nerve ring. This pattern results from secondary connections in nudibranchs and possibly other molluscs. The primary condition of a single axon bundle emerging from each cerebral ganglion is more similar to the developing nervous system in polychaete annelids than what has been recognized previously. PMID:8283184

  13. Development of a new sediment bioassay with the freshwater mudsnail Potamopyrgus antipodarum (Gastropoda: Prosobranchia); Entwicklung eines Sedimentbiotests mit der Zwergdeckelschnecke Potamopyrgus antipodarum (Gastropoda: Prosobranchia)

    Energy Technology Data Exchange (ETDEWEB)

    Duft, M.; Tillmann, M.; Markert, B. [Internationales Hochschulinstitut Zittau (Germany). Lehrstuhl Umweltverfahrenstechnik; Schulte-Oehlmann, U.; Oehlmann, J. [Frankfurt Univ. (Germany). Zoologisches Inst.

    2002-07-01

    Currently, only few organismic biotest systems are available for the assessment of effects on reproduction, which consider an exposure toward whole sediments. A well-suited test organism is the parthenogenetic mudsnail Potamopyrgus antipodarum. This ovoviviparous prosobranch snail lives in the upper layers of freshwater and brackish sediments. The number of (unshelled) embryos turned out to be a very sensitive parameter for the indication of sediment components affecting reproduction. Additionally, this endpoint allows to signal possible estrogenic sediment compounds. With this 28-day bioassay, laboratory tests on the effects of various chemicals on P. antipodarum were performed, e.g. triphenyltin and bisphenol A, in relevant environmental concentration ranges. Furthermore, the suitability of our test system for the investigation of complex and multiple level ranged contaminations was examined by means of various natural sediments from the Neisse and Odra rivers. (orig.) [German] Derzeit bestehen nur wenige etablierte organismische Testverfahren zur Erfassung von reproduktionstoxischen Effekten, die eine Exposition gegenueber Gesamtsedimenten beruecksichtigen. Ein hierfuer gut geeigneter Testorganismus ist die parthenogenetische Zwergdeckelschnecke Potamopyrgus antipodarum. Sie gehoert zu den ovoviviparen (lebendgebaerenden) Prosobranchiern und lebt in den obersten Schichten von Suess- und Brackwassersedimenten. Als empfindlicher Parameter zur Indikation reproduktionstoxisch wirkender Sedimentkomponenten erwies sich die Anzahl der (neugebildeten) Embryonen im Brutraum - dieser Endpunkt vermag zudem auf eventuell vorhandene oestrogene Wirkstoffe im Sediment hinzuweisen. Mit Hilfe dieses 28 Tage umfassenden Biotests wurden in Laboruntersuchungen die Wirkungen verschiedener Umweltchemikalien, wie z.B. Triphenylzinn und Bisphenol A, auf P. antipodarum in umweltrelevanten Konzentrationsreihen getestet. Darueber hinaus wurde die Eignung des Biotests fuer die Ermittlung und Untersuchung der Wirkung komplexer Kontaminanten anhand von verschiedenen realen Flusssedimenten unterschiedlichen Belastungsgrades - aus Neisse und Oder - erprobt. (orig.)

  14. Evaluation of the use of Olivella minuta (Gastropoda, Olividae) and Hastula cinerea (Gastropoda, Terebridae) as TBT sentinels for sandy coastal habitats.

    Science.gov (United States)

    Petracco, Marcelo; Camargo, Rita Monteiro; Berenguel, Thayana Amorim; de Arruda, Noelle C L Patrício; del Matto, Lygia A; Amado, Lílian Lund; Corbisier, Thais Navajas; Castro, Ítalo Braga; Turra, Alexander

    2015-07-01

    Tributyltin (TBT) contamination is still recorded in the environment even after its ban in antifouling paints. Since most biomonitors of TBT contamination, through imposex evaluation, are hard-bottom gastropods, the identification of soft-bottom sentinels has become useful for regions where rocky shores and coral reefs are absent. Thus, an evaluation of Olivella minuta and Hastula cinerea as monitors of TBT contamination was performed in two sandy beaches located under influence area of São Sebastião harbor (São Paulo state, Brazil), where previous and simultaneous studies have reported environmental contamination by TBT. In addition, the imposex occurrence in H. cinerea was assessed in an area with low marine traffic (Una beach), also located in São Paulo State. A moderate imposex incidence in O. minuta was detected in Pernambuco (% I = 9.36, RPLI = 4.49 and RPLIstand = 4.27) and Barequeçaba (% I = 2.42, RPLI = 0.36 and RPLIstand = 0.81) beaches, indicating TBT contamination. In contrast, more severe levels of imposex were recorded for H. cinerea in Una beach (% I = 12.45) and mainly in Barequeçaba beach (% I = 98.92, RPLI = 26.65). Our results suggest that O. minuta and H. cinerea have good potential as biomonitors for TBT based on their wide geographical distribution, common occurrence in different coastal sediment habitats, easy collection, and association with TBT-contaminated sediments. PMID:26085280

  15. Histologia das glândulas salivares dos Limacoidea e Milacidae (Gastropoda, Pulmonata Histology of the salivary glands of the Limacoidea and Milacidae (Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Ana Maria Leal-Zanchet

    2003-09-01

    Full Text Available The histology of the salivary glands of six species of Limacoidea, Boettgerilla pallens Simroth, 1912, Deroceras laeve (Müller, 1774, Deroceras reticulatum (Müller, 1774, Deroceras rodnae Grossu & Lupu, 1965, Malacolimax tenellus (Müller, 1774 and Lehmannia marginata (Müller, 1774, and a species of Milacidae, Tandonia budapestensis (Hazay, 1881 is comparatively described herein. In the glandular parenchyme four to five secretory cell types are distinguished and characterised, besides a cell type which is probably undifferentiated. The secretory cell types are classified into two groups, mucous and serous cells. Two types of mucous cells and two to three types of serous cells are distinguished. The salivary glands of the herein studied Limacoidea and Milacidae show a duct system composed of intralobular, interlobular and main ducts, each one presenting a characteristic type of epithelial lining. The results are comparatively discussed with the data available in the literature, in order to verify the correspondence between the different cell types described for other Pulmonata.

  16. Macrocyclis peruvianus (Gastropoda, Acavidae, an endemic land snail from Chile Macrocyclis peruvianus (Gastropoda, Acavidae, um caracol terrestre endêmico do Chile

    Directory of Open Access Journals (Sweden)

    Leticia F. da Silva

    2009-06-01

    Full Text Available Macrocyclis peruvianus (Lamarck, 1822 is a large terrestrial snail which is endemic in Chile. A detailed description of its shell structure, jaw, radula, palial cavity and reproductive system is presented here for the first time.Macrocyclis peruvianus (Lamarck, 1822 é um grande caracol terrestre endêmico do Chile. Uma descrição detalhada da esculturação de sua concha, rádula, mandíbula, cavidade palial e sistema reprodutor são apresentados aqui pela primeira vez.

  17. What remains after 2 months of starvation? Analysis of sequestered algae in a photosynthetic slug, Plakobranchus ocellatus (Sacoglossa, Opisthobranchia), by barcoding.

    Science.gov (United States)

    Christa, Gregor; Wescott, Lily; Schäberle, Till F; König, Gabriele M; Wägele, Heike

    2013-02-01

    The sacoglossan sea slug, Plakobranchus ocellatus, is a so-called long-term retention form that incorporates chloroplasts for several months and thus is able to starve while maintaining photosynthetic activity. Little is known regarding the taxonomy and food sources of this sacoglossan, but it is suggested that P. ocellatus is a species complex and feeds on a broad variety of Ulvophyceae. In particular, we analysed specimens from the Philippines and starved them under various light conditions (high light, low light and darkness) and identified the species of algal food sources depending on starvation time and light treatment by means of DNA-barcoding using for the first time the combination of two algal chloroplast markers, rbcL and tufA. Comparison of available CO1 and 16S sequences of specimens from various localities indicate a species complex with likely four distinct clades, but food analyses do not indicate an ecological separation of the investigated clades into differing foraging strategies. The combined results from both algal markers suggest that, in general, P. ocellatus has a broad food spectrum, including members of the genera Halimeda, Caulerpa, Udotea, Acetabularia and further unidentified algae, with an emphasis on H. macroloba. Independent of the duration of starvation and light exposure, this algal species and a further unidentified Halimeda species seem to be the main food source of P. ocellatus from the Philippines. It is shown here that at least two (or possibly three) barcode markers are required to cover the entire food spectrum in future analyses of Sacoglossa. PMID:23108662

  18. Distribution and Fauna of Opisthobranchia along the Zhejiang Coast%浙江近海后鳃类软体动物的分布及其区系

    Institute of Scientific and Technical Information of China (English)

    尤仲杰

    2004-01-01

    报道了浙江近海的后鳃类97种,分别隶属于7目30科44属.其中我国沿岸广温广布种14种,主要分布于东海和南海的亚热带种50种,南海的热带种18种,渤、黄海延伸到东海北部的暖温带种15种.

  19. Molluscicidal activity of various solvent extracts from Solanum nigrum var. villosum L. aerial parts against Galba truncatula

    Directory of Open Access Journals (Sweden)

    Hammami H.

    2011-02-01

    Full Text Available Molluscicidal activity of Solanum nigrum var. villosum (morelle velue extracts and their fractions were tested against the mollusca gastropoda Galba truncatula intermediate host of Fasciola hepatica. The results indicated that the hydro-methanol (MeOH-H2O immature fruit extract possess the highest molluscicidal activity (LC50 = 3.96 mg/L against Galba truncatula compared with other tested compounds. After acido-basic treatment, the methanolic extract fraction isolated from the immature fruits and the richest in alkaloids was the most toxic (LC50 = 1.65 mg/L. The fractions richest in saponosides obtained from the hydromethanolic and methanolic extracts of immature fruits showed interesting molluscicidal activities (LC50 = 6.15 mg/L and LC50 = 7.91 mg/L, respectively. The observed molluscicide activity could be attributed to the presence of alkaloids or saponosides. So, the immature fruits of Solanum nigrum var. villosum could be substrates of choice for molluscicide activity. In addition, total alkaloids and saponosides present in this plant deserve further investigations in order to identify the active principles and demonstrate their activities on mollusks in their natural habitat. According to the World Health Organization’s guidelines on screening for plant molluscicides, use of these fractions may add to the arsenal of methods to control snail transmitting fasciolosis in tropical and Third World countries where fasciolosis is a common disease.

  20. Wetland macroinvertebrates of Prentiss Bay, Lake Huron, Michigan: diversity and functional group composition

    Science.gov (United States)

    Merritt, R.W.; Benbow, M.E.; Hudson, P.L.

    2002-01-01

    The Great Lakes support many fish and waterbirds that depend directly or indirectly on coastal wetlands during some portion of their life cycle. It is known that macroinvertebrates make up an important part of wetland food webs and ecosystem function; however, our understanding of species distribution within and among wetlands has only recently received attention. We investigated the macroinvertebrates of a freshwater marsh (Prentiss Bay) in the Les Chenaux Island Area of Northern Lake Huron, Michigan. Macroinvertebrate taxa diversity and functional feeding group composition were compared between two habitats. A shallow depositional habitat with higher vegetation diversity and little wave action was compared to a deeper erosional habitat with fewer plant species and more wave action. A total of 83 taxa were collected over the summer of 1996, representing two phyla (Arthropoda and Mollusca) and five classes (Arachnida, Bivalvia, Malacostraca, Gastropoda and Insecta). A total of 79 genera were identified, with 92% being insects (39 families composed of at least 73 genera). Of the total, 42 insect genera were common to both habitats,while relatively fewer were collected exclusively from the erosional compared the depositional habitat. When habitats were pooled, predators comprised about 50% of the functional group taxa, while gathering collectors and shredders each were about 20%. Filtering collectors and scrapers each represented functional groups were lower. These data suggest that vegetation diversity, depth and wave action affect taxa composition and functional group organization of the Prentiss Bay marsh.

  1. Feeding pattern and use of reproductive habitat of the Striped toad Rhinella crucifer (Anura: Bufonidae from Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo B. Ferreira

    2009-12-01

    Full Text Available Diet composition, foraging mode, and using of reproductive habitat of Rhinella crucifer was studied in an artificial pond in Espírito Santo, Brazil. The favored substrate was leaf litter, followed by Cyperaceae/Poaceae. Calling sites, preferred for 23.3 % (n = 7 of the observed toads, were within the water, with only the head not submerged. We analyzed a total of 61 specimens, mainly males (98.5% male and 1.5% female. Seven categories of prey were found in the stomach contents: Coleoptera, Hymenoptera (Formicidae, Isoptera, Lepidoptera, Orthoptera, Gastropoda (Mollusca, Opilionida (Arachnida. Our studies indicate that the diet of Rhinella crucifer consists mainly of terrestrial colonial arthropods. Formicidae was the predominant food item in frequency of occurrence, number of prey and weight. Isoptera and Coleoptera were also relevant in terms of weight. Neither large ontogenetic dietary nor seasonal shifts were observed in the population studied. Our results suggest that no intraspecific food resource partitioning occurs in adult or juveniles. Rhinella crucifer adults avoid competition inhabiting different home range habitats and seem to be ant-specialist with a wide foraging mode.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Record of imposex in Cronia konkanensis (Gastropoda, Muricidae) from Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    VishwaKiran, Y.; Anil, A.C.

    neogastropod species Cronia konkanensis (Melvill, 1893) (Fa: Muricidae) collected from Goa waters located along the west coast of India. The frequency of imposex was found to be in the range of 90-100% in the animals collected from Marmugao Harbour while...

  7. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    Science.gov (United States)

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants. PMID:27324580

  8. A new genus and species of Aclididae (Gastropoda) from off Tenerife, Canary Islands

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Warén, A.

    1987-01-01

    Dr. Manuel Carrillo Pèrez (Universidad de la Laguna) has sent some dredge-samples to the first author. This material contained many interesting molluscs, not mentioned by Nordsieck & Talavera (1979). Amongst them was a very peculiar gastropod species, which was difficult to identify. Based on some s

  9. Reproductive biology of Oxychilus(Atlantoxychilus) spectabilis (Milne-Edwards, 1885) (Gastropoda: Pulmonata): a gametogenic approach

    OpenAIRE

    Ferreira, Ana Filipa; Martins, António M. de Frias; Cunha, Regina Tristão da; Melo, Paulo Jorge; A.R. Rodrigues

    2013-01-01

    The taxonomic status and anatomy of Oxychilus (Atlantoxychilus) spectabilis (Milne-Edwards, 1885), an endemic land snail from Santa Maria Island, Azores, has been subject of detailed study, yet information about its life history is wanting. This study describes the reproductive cycle of O. (A.) spectabilis and assesses the validity of three morphometric shell parameters as maturation diagnostic characters. Our results indicate that individuals are reproductively more active from May to Novemb...

  10. Systematics and Distribution of Siphocypraea mus and Propustularia surinamensis (Gastropoda, Cypraeidae)

    NARCIS (Netherlands)

    Coomans, H.E.

    1963-01-01

    The systematic place of “Cypraea” mus Linné is discussed, and it is concluded that the species belongs in Siphocypraea (Akleistostoma). The “varieties” tuberculata Gray and bicornis Sowerby should be withdrawn; they are only forms with callosities. Callus formations are often found in Cypraeidae. Th

  11. A new species of Nassarius (Gastropoda, Nassariidae from Canopus Bank, off Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Daniel Abbate

    2013-01-01

    Full Text Available Nassarius levis sp. nov. is described from Canopus Bank, off Ceará, Northeast Brazil, based on shell morphology. It differs from other Brazilian species of the genus in having a more elongate shell, with a weakly developed parietal shield and a notably smooth surface. This last trait has not yet been described among the Western Atlantic Nassarius, but it is common to other congeners from the Eastern Atlantic, such as Nassarius elatus (Gould, 1845 and the Indo-Pacific, such as Nassarius excellens (Kuroda & Habe, 1961.

  12. Atlanta ariejansseni, a new species of shelled heteropod from the Southern Subtropical Convergence Zone (Gastropoda, Pterotracheoidea)

    Science.gov (United States)

    Wall-Palmer, Deborah; Burridge, Alice K.; Peijnenburg, Katja T.C.A.

    2016-01-01

    Abstract The Atlantidae (shelled heteropods) is a family of microscopic aragonite shelled holoplanktonic gastropods with a wide biogeographical distribution in tropical, sub-tropical and temperate waters. The aragonite shell and surface ocean habitat of the atlantids makes them particularly susceptible to ocean acidification and ocean warming, and atlantids are likely to be useful indicators of these changes. However, we still lack fundamental information on their taxonomy and biogeography, which is essential for monitoring the effects of a changing ocean. Integrated morphological and molecular approaches to taxonomy have been employed to improve the assessment of species boundaries, which give a more accurate picture of species distributions. Here a new species of atlantid heteropod is described based on shell morphology, DNA barcoding of the Cytochrome Oxidase I gene, and biogeography. All specimens of Atlanta ariejansseni sp. n. were collected from the Southern Subtropical Convergence Zone of the Atlantic and Indo-Pacific oceans suggesting that this species has a very narrow latitudinal distribution (37–48°S). Atlanta ariejansseni sp. n. was found to be relatively abundant (up to 2.3 specimens per 1000 m3 water) within this narrow latitudinal range, implying that this species has adapted to the specific conditions of the Southern Subtropical Convergence Zone and has a high tolerance to the varying ocean parameters in this region. PMID:27551204

  13. Ecomorphological Analyses of Marine Mollusks' Shell Thickness of Rapana venosa (VALENCIENNES, 1846 (Gastropoda: Muricidae

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    Igor P. Bondarev

    2013-10-01

    Full Text Available Shell thickness of Rapana venosa was investigated from ecologically different places of the Azov – Black Sea basin. In the formation of the shell thickness there are two major trends: thickening with age, and inversely proportional to the size of the thickening of even-aged individuals of the same population. Shell thickness formation was analyzed in connection with biotic and abiotic environmental factors of influence. R. venosa ontogeny is not conducive to the rapid succession newly acquired characters in local populations. The formation of a thick shell is mainly the individual response of bions to the environment. Individuals’ of the same type reaction is the cause of formation of specific conchological characters of separate populations or parts thereof. Mechanical impacts (e.g. damage by breaking predators and storm waves hitting on rocks have no significant effect on the increasing of thickness of shells. Comparative analysis of the thickness of the shell of R. venosa from areas with different salinity shows that the direct relationship between these parameters is absent. R. venosa is capable of forming its own salinity medium in the mantle cavity, which is different from the external environment. The main factor influencing the formation of a thick-walled shell is the amplitude of the temperature fluctuations in the locality. Shell thickness of R. venosa was considered as ecomorphological character in comparison with the same feature of shell-bearing mollusks from the World Ocean at different latitude zones. It is shown that high temperature gradient is one of the most important factors of forming a thick shell. The greatest show this intertidal species and ecomorphs of temperate and high latitudes, where the temperature gradients are most expressed.

  14. Well-known and little-known: miscellaneous notes on Peruvian Orthalicidae (Gastropoda, Stylommatophora)

    NARCIS (Netherlands)

    Breure, A.S.H.; Mogollón Avila, V.

    2010-01-01

    The family Orthalicidae is well represented in Peru but, like in other families, some species are wellknown and others have not been reported on since their original descriptions. In this paper we present new records for well-known species and elucidate the status of several lesser known taxa. Four

  15. Milax Clerxi nov. spec., eine neue Nacktschnecke aus Südjugoslawien (Gastropoda, Pulmonata, Milacidae)

    NARCIS (Netherlands)

    Rähle, W.

    1977-01-01

    Durch das Entgegenkommen von Herrn Dr. C. O. van Regteren Altena, Leiden, erhielt der Verfasser eine Serie juveniler, fast erwachsener und erwachsener Nacktschnecken aus der Gattung Milax zur Bearbeitung, welche aus der Umgebung der Stadt Ohrid in Mazedonien stammen und dort im Sommer 1974 von Drs.

  16. Systematics of the family Plectopylidae in Vietnam with additional information on Chinese taxa (Gastropoda, Pulmonata, Stylommatophora

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    Barna Páll-Gergely

    2015-01-01

    Full Text Available Vietnamese species from the family Plectopylidae are revised based on the type specimens of all known taxa, more than 600 historical non-type museum lots, and almost 200 newly-collected samples. Altogether more than 7000 specimens were investigated. The revision has revealed that species diversity of the Vietnamese Plectopylidae was previously overestimated. Overall, thirteen species names (anterides Gude, 1909, bavayi Gude, 1901, congesta Gude, 1898, fallax Gude, 1909, gouldingi Gude, 1909, hirsuta Möllendorff, 1901, jovia Mabille, 1887, moellendorffi Gude, 1901, persimilis Gude, 1901, pilsbryana Gude, 1901, soror Gude, 1908, tenuis Gude, 1901, verecunda Gude, 1909 were synonymised with other species. In addition to these, Gudeodiscus hemmeni sp. n. and G. messageri raheemi ssp. n. are described from north-western Vietnam. Sixteen species and two subspecies are recognized from Vietnam. The reproductive anatomy of eight taxa is described. Based on anatomical information, Halongella gen. n. is erected to include Plectopylis schlumbergeri and P. fruhstorferi. Additionally, the genus Gudeodiscus is subdivided into two subgenera (Gudeodiscus and Veludiscus subgen. n. on the basis of the morphology of the reproductive anatomy and the radula. The Chinese G. phlyarius werneri Páll-Gergely, 2013 is moved to synonymy of G. phlyarius. A spermatophore was found in the organ situated next to the gametolytic sac in one specimen. This suggests that this organ in the Plectopylidae is a diverticulum. Statistically significant evidence is presented for the presence of calcareous hook-like granules inside the penis being associated with the absence of embryos in the uterus in four genera. This suggests that these probably play a role in mating periods before disappearing when embryos develop. Sicradiscus mansuyi is reported from China for the first time.

  17. Progenesis in the evolution of the nudibranch mollusks genus Dendronotus (Gastropoda: Nudibranchia).

    Science.gov (United States)

    Ekimova, I A; Malakhov, V V

    2016-03-01

    The morphology and postlarval ontogenesis of the radula in 11 species of the genus Dendronotus Alder et Hancock, 1845, has been studied. Four types of radula are recognized in adult mollusks. Proposed evidence suggests that small species of Dendronotus have evolved by progenesis. PMID:27193883

  18. New Odostomia species (Gastropoda, Heterobranchia, Pyramidellidae) from the Miocene Pebas Formation of Western Amazonia (Peru, Colombia)

    OpenAIRE

    Aartsen, van, J.J.; Wesselingh, F.P.

    2000-01-01

    Odostomia nuttalli spec. nov. and O. coluhensis spec. nov. are described from the Miocene Pebas Formation of Peruvian and Columbian Amazonia. A third pyramidellid snail is also diagnosed. These species are indicators for marine influence in the late Middle to early Late Miocence of Western Amazonia. Some ecological implications are discussed.

  19. Comparative reproductive anatomy in the South African giant land snails (Gastropoda: Pulmonata: Achatinidae)

    NARCIS (Netherlands)

    Mead, A.R.

    2004-01-01

    The history and current taxonomic status of 62 nominal taxa are revised that have been associated in the literature with the subgenus Tholachatina Bequaert, 1950, of genus Archachatina Albers, 1850, and the genus Cochlitoma Férussac, 1821, in the land snail family Achatinidae Swainson, 1840. Tangibl

  20. Diversity of Edible Mollusc (Gastropoda and Bivalvia at Selected Divison of Sarawak, Malaysia

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    Hadi Hamli

    2012-01-01

    Full Text Available Diversity of edible mollusc was studied at eight divisions of Sarawak from August 2010 to May 2011. At each division, diversity and number of species were collected from road site selling out lets and local wet markets. Total number of mollusc was comprised of 29 species namely  Solen regularies, S. lamarckii,  Pharella acutidens, Anadara granosa, Pholas orientalis, Gluconome virens, Circe scripta, Anodonta woodina, Paphia undulata, Amusium pleuronectes, Meretrix meretrix, M. lyrata, Polymesoda bengalensis, P. erosa and P. expansa  for bivalve and  Cerithidea rizophorarum, C. obtusa, Telescopium telescopium, Clithon retropictus, Nerita articulate, N. chamaeleon, N. albicilla, Ellobium aurisjuda, Trochus radiates, Planaxis sulcatus, Monodonta labio, Turbo crasus, Thais aculate  and Melo melo  for gastropod. The species number of bivalve was recorded highest (15 species in mollusc group from Sarawak. Mollusc diversity was found highest (14 species in Bintulu and lowest (1 species in the division of Sarikei. From this study, there is a wide chance of research to further explore both on the possibility of commercial value and ecosystem conservation.

  1. [Growth of Strombus gigas (Gastropoda: Strombidae) snail in 4 environments of Quintana Roo, Mexico].

    Science.gov (United States)

    Navarrete, A J

    2001-03-01

    The growth rate of queen conch cultured in pens was studied from October 1993 to March 1994. Sixteen pens (50 m2 each, four pens per environment), were set in four environments: Thalassia, Thalassia-sand, Sand and Coral within a reef lagoon on Punta Gavilan and Banco Chinchorro. Twenty conchs were introduced in each pen (sizes: 100-120, 120-140, 140-160 and 160-180 mm shell length) and measured monthly to the nearest mm. Growth rate was assessed by two methods: a) shell marginal mean increase and b) the Gulland-Holt method considering all conch within pens. In the first method, the environment Sand had the highest growth (3.21 +/- 0.26 mm/month) at Punta Gavilan, whereas at Banco Chinchorro, highest growth was recorded in Coral (2.31 +/- 0.44 mm/month). Considering the second method, highest asymptotic length conch in Punta Gavilan occurred in Thalassia-sand (287.5 mm), whereas in Banco Chinchorro the highest asymptotic length was measured in Sand (318.1 mm). There were significant differences in growth between sites; juvenile growth is related with habitat quality mainly food availability. PMID:11795173

  2. Burnaia Miller, 2001 (Gastropoda, Heterobranchia, Nudibranchia): a facelinid genus with an Aeolidiidae's outward appearance

    Science.gov (United States)

    Carmona, Leila; Pola, Marta; Gosliner, Terrence M.; Cervera, Juan Lucas

    2015-09-01

    In recent years, several morphological and molecular analyses have been undertaken to study the phylogenetic systematics of Aeolidiidae members. The monospecific genus Burnaia could not be included in the previous analysis, due to the lack of material. This study includes two specimens of Burnaia helicochorda from Australia and places them in their systematic position using two mitochondrial and one nuclear genes (COI and 16S, and H3, respectively). A description of its anatomy is also included with colour pictures of the animal and scanning electron micrographs of radula and jaws. Based on our results, B. helicochorda does not belong to Aeolidiidae since it appears nested among some facelinids.

  3. Eine neue Deroceras-Art (Gastropoda, Pulmonata, Agriolimacidae) von der Griechischen Insel Samos

    NARCIS (Netherlands)

    Rähle, W.

    1983-01-01

    Im Frühjahr 1982 sammelte Herr Jens Hemmen aus Wiesbaden (Bundesrepublik Deutschland) auf der Insel Samos zahlreiche Individuen einer noch unbekannten Deroceras-Art, die ihren anatomischen Merkmalen nach zur Untergattung Plathystimulus Wiktor, 1973 gehört. Die Tiere waren fast alle erwachsen und erm

  4. A nomenclator of extant and fossil taxa of the Melanopsidae (Gastropoda, Cerithioidea)

    Science.gov (United States)

    Neubauer, Thomas A.

    2016-01-01

    Abstract This nomenclator provides details on all published names in the family-, genus-, and species-group, as well as for a few infrasubspecific names introduced for, or attributed to, the family Melanopsidae. It includes nomenclaturally valid names, as well as junior homonyms, junior objective synonyms, nomina nuda, common incorrect subsequent spellings, and as far as possible discussion on the current status in taxonomy. The catalogue encompasses three family-group names, 79 genus-group names, and 1381 species-group names. All of them are given in their original combination and spelling (except mandatory corrections requested by the Code), along with their original source. For each family- and genus-group name, the original classification and the type genus and type species, respectively, are given. Data provided for species-group taxa are type locality, type horizon (for fossil taxa), and type specimens, as far as available. PMID:27551193

  5. Summarizing data on the Inchoatia taxa, including Inchoatia megdova bruggeni subspec. nov. (Gastropoda, Pulmonata, Clausiliidae)

    NARCIS (Netherlands)

    Gittenberger, E.; Uit de Weerd, D.R.

    2009-01-01

    An annotated checklist for the genus Inchoatia is provided. The old distributional data are converted into modern geographical names and completed with UTM codes. A new subspecies is described as Inchoatia megdova bruggeni subspec. nov.

  6. New Odostomia species (Gastropoda, Heterobranchia, Pyramidellidae) from the Miocene Pebas Formation of Western Amazonia (Peru, Colombia)

    NARCIS (Netherlands)

    Aartsen, van J.J.; Wesselingh, F.P.

    2000-01-01

    Odostomia nuttalli spec. nov. and O. coluhensis spec. nov. are described from the Miocene Pebas Formation of Peruvian and Columbian Amazonia. A third pyramidellid snail is also diagnosed. These species are indicators for marine influence in the late Middle to early Late Miocence of Western Amazonia.

  7. The Model Organism Hermissenda crassicornis (Gastropoda: Heterobranchia) Is a Species Complex.

    Science.gov (United States)

    Lindsay, Tabitha; Valdés, Ángel

    2016-01-01

    Hermissenda crassicornis is a model organism used in various fields of research including neurology, ecology, pharmacology, and toxicology. In order to investigate the systematics of this species and the presence of cryptic species in H. crassicornis, we conducted a comprehensive molecular and morphological analysis of this species covering its entire range across the North Pacific Ocean. We determined that H. crassicornis constitutes a species complex of three distinct species. The name Hermissensa crassicornis is retained for the northeast Pacific species, occurring from Alaska to Northern California. The name H. opalescens is reinstated for a species occurring from the Sea of Cortez to Northern California. Finally, the name H. emurai is maintained for the northwestern species, found in Japan and in the Russian Far East. These three species have consistent morphological and color pattern differences that can be used for identification in the field. PMID:27105319

  8. Population biology of the gastropod Olivella minuta (Gastropoda, Olividae) on two sheltered beaches in southeastern Brazil

    Science.gov (United States)

    Petracco, Marcelo; Camargo, Rita Monteiro; Tardelli, Daniel Teixeira; Turra, Alexander

    2014-10-01

    The structure, dynamics and production of two populations of the olivid gastropod Olivella minuta were analyzed through monthly sampling from November 2009 through October 2011 on two sandy beaches, Pernambuco (very sheltered) and Barequeçaba (sheltered) in São Paulo state (23°48'S), southeastern Brazil. On both beaches, samples were taken along five transects established perpendicular to the waterline. Parameters of the von Bertalanffy growth function were estimated for both populations from monthly length-frequency distributions. The production and turnover ratios were determined using the mass-specific growth rate method. The population on the less-sheltered Barequeçaba Beach was less abundant (120.02 ± 22.60 ind m-1) than on Pernambuco Beach (3295.30 ± 504.86 ind m-1 (±SE)), which we attribute to the greater environmental stability of the latter. Conversely, the mean length, size of the largest individual, and body mass were higher at Barequeçaba than at Pernambuco. The significant differences in the growth of individuals and the mortality rate (Z) between the beaches suggest that density-dependent processes were operating at Pernambuco Beach. The production and P/B ratio at Pernambuco (12.12 g AFDM m-1 year-1 and 1.91 year-1) were higher than at Barequeçaba (0.82 g AFDM m-1 year-1 and 1.06 year-1). The difference in production can be attributed to the higher abundance on Pernambuco, while the higher P/B ratio resulted from the scarcity of smaller individuals in the intertidal zone of Barequeçaba. The P/B ratio estimated for the Pernambuco population is the highest found so far for sandy-beach gastropods. This study reinforces the theory that biological interactions are important regulators of sheltered sandy-beach populations. Future studies with multi-beach sampling are needed to better understand the life-history variations of O. minuta along gradients of degree of exposure of sandy beaches.

  9. First record of Calma gobioophaga Calado and Urgorri, 2002 (Gastropoda: Nudibranchia in the Mediterranean Sea

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    J. PRKIC

    2014-07-01

    Full Text Available Specimens of the nudibranch genus Calma were observed under stones at two Croatian localities while feeding on gobiid eggs. Some ambiguous morphological features compared with the original descriptions of the known species of the genus, C. glaucoides and C. gobioophaga, hampered an easy identification. Genetic data (COI and 16S sequences confirmed the distinction between the two species of the genus Calma, and allowed to unambiguously identify the Croatian specimens as Calma gobioophaga. This is the first record of this species for the Mediterranean and extends remarkably its distribution range. Finally, the eggs fed by the Croatian specimens have been taxonomically identified by using the 12S rDNA marker as Gobius cobitis.

  10. Gymnodoris pattani, a new dorid nudibranch from Pattani Bay, Gulf of Thailand (Gastropoda, Nudibranchia)

    NARCIS (Netherlands)

    Swennen, C.

    1996-01-01

    Several specimens of a new dorid nudibranch have been found in Yaring River, Pattani Province in southern Thailand. The species clearly belongs to the genus Gymnodoris, and is described and named G. pattani. It can be distinguished from all other species described in the genus by its translucently g

  11. Notes on Rivomarginella electrum (Reeve, 1865) from Lampung, South Sumatra (Gastropoda, Marginellidae)

    NARCIS (Netherlands)

    Djajasasmita, Machfudz; Coomans, Henry E.

    1980-01-01

    Specimens of the freshwater marginellid Rivomarginella electrum (Reeve) were collected in South Sumatra. The erroneous spelling of the type locality is corrected into Lake Jepara. The animal, radula and ecology are described for the first time; living specimens were observed in an aquarium. The spec

  12. Review of the geographic distribution of Hoffmannola hansi (Gastropoda: Pulmonata) in the Mexican Pacific

    OpenAIRE

    Omar Hernando Avila-Poveda; Quetzalli Yasú Abadia-Chanona; Raúl Herrera-Fragoso; Benoît Dayrat

    2014-01-01

    Hoffmannola hansi (Mexican intertidal leather slug) is traditionally reported as an endemic species to the Gulf of California, Mexico. However, its presence in the southern Mexican Pacific has been mentioned in regional checklists and reports. Here we provide new records of H. hansi populations from at least 3 locations from Oaxaca, Mexico. The anatomical characteristics useful for H. hansi identification are described for both, living and preserved specimens. Specimens reports from the Gulf ...

  13. New taxa of terrestrial molluscs from Turkey (Gastropoda, Pristilomatidae, Enidae, Hygromiidae, Helicidae

    Directory of Open Access Journals (Sweden)

    Burçin Gümüs

    2012-02-01

    Full Text Available This paper reports on results of several collecting trips of the authors in Turkey. In the course of this research, a long-lasting question was addressed. It could be proven that the nominal species Bulimus frivaldskyi L. Pfeiffer, 1847 is closely related to Meijeriella canaliculata Bank, 1985, and thus this species is shifted from the genus Ena Turton, 1831, to the genus Meijeriella Bank, 1985. Meijeriella canaliculata Bank, 1985, could be recorded from Turkey for the first time. The nomenclatural situation of the species Euchondrus septemdentatus (Roth, 1839 vs. its replacement name Euchondrus borealis (Mousson, 1874 is discussed. A new arrangement of the species formely comprised in the genus Zebrina Held, 1837 is presented, and the genera Rhabdoena Kobelt & Moellendorff, 1902, and Leucomastus A. Wagner, 1927 are re-established. The following species and subspecies new to science could be described: Vitrea gostelii sp. n. (Pristilomatidae, Turanena demirsoyi sp. n., Euchondrus paucidentatus sp. n., Rhabdoena gostelii sp. n. (all Enidae, Metafruticicola kizildagensis sp. n. (Hygromiidae, and Assyriella thospitis menkhorsti ssp. n. (Helicidae. For several other species, new distribution records are listed.

  14. Sense organs in Spongiobranchaea australis d’Orbigny, 1835 (Gastropoda, Pteropoda)

    NARCIS (Netherlands)

    Spoel, van der S.

    1964-01-01

    The sense organs: the labial tentacles, eyes, rhinophores, osphradium and statocysts of Spongiobranchaea australis d’Orbigny, 1835 are described together with their innervation. The descriptions are based on serial sections of three animals.

  15. Locomotion of Stramonita haemastoma (Linnaeus (Gastropoda, Muricidae on a mixed shore of rocks and sand

    Directory of Open Access Journals (Sweden)

    Marcos G. Papp

    2001-03-01

    Full Text Available Mixed shores of rocks and sand are appropriate systems for the study of limitations that the isolation of rocks may impose for gastropods that typically inhabit rocky shores. We marked 52 Stramonita haemastoma (Linnaeus, 1767 snails on a mixed shore and found that 34 of them moved between rocks one to four times during 15 surveys in a period of 72 days. In the experiments, the snails moved on rock by continuous, direct, ditaxic, alternate undulations of the foot sole but on submerged sand they used slower arrhythmic discontinuous contractions of the foot sole. They switched between modes of locomotion in response to the type and topography of the substrate and possibly to water dynamics. In nature, snails moved between rocks forming aggregations where they oviposited. This may have masked other causes of movement, such as availability of prey. Most snails burrowed into the sand when the rocks became exposed during low tides. Further experiments are needed to explicitly address the possible causes of movements among rocks and burial.

  16. Perotrochus caledonicus (Gastropoda: Pleurotomariidae revisited: descriptions of new species from the South-West Pacific

    Directory of Open Access Journals (Sweden)

    Patrick Anseeuw

    2015-08-01

    Full Text Available Morphological (shell and molecular examination of a large suite of specimens of pleurotomariids from around New Caledonia and the Coral Sea reveals the existence of four species in the complex of Perotrochus caledonicus: Perotrochus deforgesi Métivier, 1990 and P. pseudogranulosus sp. nov. live allopatrically on the plateaus and guyots of the Coral Sea; Perotrochus caledonicus Bouchet & Métivier, 1982 and Perotrochus wareni sp. nov. live sympatrically - but essentially not syntopically - on the slopes of New Caledonia, Norfolk Ridge and the Loyalty Ridge. All species live in the 300–500 m interval, and together form a significant component of the mollusc fauna living on hard bottoms in the SW Pacific, with individual dredge hauls containing up to 25 specimens of Perotrochus.

  17. Systematics of Ariantinae (Gastropoda, Pulmonata, Helicidae), a new approach to an old problem

    NARCIS (Netherlands)

    Groenenberg, D.S.J.; Subai, P.; Gittenberger, E.

    2016-01-01

    A new starting-point in Ariantinae systematics is presented by combining data on traditional shell morphology and genital anatomy, with phylogeny reconstructions based on DNA sequence data. For nearly all genera and subgenera one or more shells are depicted and drawings of the proximal part of the g

  18. Clausiliidae (Gastropoda, Pulmonata) collected by the Netherlands biological expedition to Turkey in 1959

    NARCIS (Netherlands)

    Loosjes, F.E.

    1963-01-01

    The route of the Netherlands Biological Expedition to Turkey in 1959 is published elsewhere (Hennipman a.o., 1961; Anonymus, 1963). As is mentioned there also, the zoological material collected is preserved in the Rijksmuseum van Natuurlijke Historie at Leiden. I am greatly indebted to Dr. C. O. van

  19. Synopsis of Central Andean Orthalicoid land snails (Gastropoda, Stylommatophora), excluding Bulimulidae

    OpenAIRE

    Abraham S.H. Breure; Avila, Valentín Mogollón

    2016-01-01

    Abstract A faunal overview is presented of the molluscan families Amphibulimidae , Megaspiridae , Odontostomidae , Orthalicidae , Simpulopsidae in Bolivia, Ecuador, and Peru. These Central Andean countries are known for their biodiverse malacofauna, of which the superfamily Orthalicoidea takes relatively a large share. In this paper the five families containing 103 (sub)species, for which systematic information (original publication, type locality, type depository, summarizing literature) and...

  20. Review of the genus Endothyrella Zilch, 1960 with description of five new species ( Gastropoda , Pulmonata , Plectopylidae )

    OpenAIRE

    Páll-Gergely, Barna; Budha, Prem B.; Naggs, Fred; Backeljau, Thierry; Asami,Takahiro

    2015-01-01

    Abstract All known taxa of the genus Endothyrella Zilch, 1960 (family Plectopylidae ) are reviewed. Altogether 23 Endothyrella species are recognized. All species are illustrated and whenever possible, photographs of the available type specimens are provided. Five new species are described: Endothyrella angulata Budha & Páll-Gergely, sp. n., Endothyrella dolakhaensis Budha & Páll-Gergely, sp. n. and Endothyrella nepalica Budha & Páll-Gergely, sp. n. from Nepal, Endothyrella robustistriata Pál...

  1. Review of the genus Endothyrella Zilch, 1960 with description of five new species (Gastropoda, Pulmonata, Plectopylidae)

    OpenAIRE

    Pall-Gergely, Barna; Budha, Prem B.; Naggs, Fred; Backeljau, Thierry; Asami,Takahiro

    2015-01-01

    All known taxa of the genus Endothyrella Zilch, 1960 (family Plectopylidae) are reviewed. Altogether 23 Endothyrella species are recognized. All species are illustrated and whenever possible, photographs of the available type specimens are provided. Five new species are described: E. angulata Budha & Páll-Gergely, sp. n., E. dolakhaensis Budha & Páll-Gergely, sp. n. and E. nepalica Budha & Páll-Gergely, sp. n. from Nepal, E. robustistriata Páll-Gergely, sp. n. from the Naga Hills, India, and ...

  2. Systematics of Ariantinae (Gastropoda, Pulmonata, Helicidae), a new approach to an old problem

    OpenAIRE

    Groenenberg, D.S.J.; Subai, P.; Gittenberger, E.

    2016-01-01

    A new starting-point in Ariantinae systematics is presented by combining data on traditional shell morphology and genital anatomy, with phylogeny reconstructions based on DNA sequence data. For nearly all genera and subgenera one or more shells are depicted and drawings of the proximal part of the genital organs are shown to illustrate the morphological diversification within the subfamily. For as much as our material allowed it, partial sequences are presented for Histone H3 (H3), Cytochrome...

  3. Two new species of Thaumastus (Gastropoda: Pulmonata: Orthalicidae: Bulimulinae from the state of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Meire Silva Pena

    2011-08-01

    Full Text Available Two new species of Thaumastus (Thaumastus from the state of Minas Gerais, southeastern Brazil, are described. They are diagnosed and characterized by the morphology of the shell and soft parts and compared with Brazilian species of the subgenus Thaumastus s.s. Martens, 1860. Thaumastus (T. parvus sp. nov. is similar to T. (T. baixoguanduensis Pena, Coelho & Salgado, 1996 but can be distinguished by the smaller size, smaller number of plates in the jaw, different number of follicle groups in the ovotestis and form of the fertilization complex. Thaumastus (T. caetensis sp. nov. is similar to T. (T. largillierti (Philippi, 1845 but differs by the width and the contour of the parietal side of the shell aperture. T. (T. caetensis is also closer to Thaumastus (T. baixoguanduensis but can be distinguished by the smaller dimensions (height, width and number of protoconch whorls, the lack of a transversal light band on the body whorl, the jaw with smaller number of plates, and the radula with 35 teeth. In the soft parts, this new species differs also in the number of follicle gatherings in ovotestis, fertilization complex with globose shape, and penian retractor muscle terminally and laterally attached to flagellum

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

    Directory of Open Access Journals (Sweden)

    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. 

  5. 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.

  6. Life history of the bathyal octopus Pteroctopus tetracirrhus (Mollusca, Cephalopoda) in the Mediterranean Sea

    Science.gov (United States)

    Quetglas, Antoni; Ordines, Francesc; González, María; Franco, Ignacio

    2009-08-01

    The life cycle of the deep-sea octopus Pteroctopus tetracirrhus was studied from monthly samples obtained throughout the year in different areas of the western Mediterranean (mainly around the Balearic Islands and along the coast of the Iberian Peninsula). A total of 373 individuals (205 females, 168 males) were analyzed; females ranged from 4.5 to 14.0 cm mantle length (ML) and males from 4.5 to 11.5 cm ML. There were few small-sized octopuses (octopus inhabits the lower continental shelf and upper slope in both areas, primarily between 200 and 500 m depth. Modal lengths were followed from autumn, when recruits were caught by trawlers, to summer, when reproduction took place. Females grew from 8 to 10 cm ML from winter to spring, but this modal size did not increase further in summer; males grew from 7 to 9 cm ML from winter to spring. The total disappearance of large individuals after summer suggests a life cycle lasting a single year. The evolution of the monthly mean sizes showed that the growth was best described by log-linear functions in both sexes. The length at first maturity was clearly higher in females (12 cm ML) than in males (8 cm ML). A total of 30 different prey items, belonging to four major taxonomic groups (crustaceans, osteichthyes, cephalopods and gastropods), were identified in the stomach contents. The diet of the octopus was based on crustaceans and teleosts, which accounted for 75% and 23% of the prey items, respectively. Cephalopods and gastropods were accessory prey as they only represented 1.6% and 0.7%, respectively, of the total. The octopus showed a marked preference for the benthic fish Symphurus nigrescens and the endobenthic crustacean Alpheus glaber. The bathymetric distribution of P. tetracirrhus coincides with those of these two main prey, which suggests that the distribution of the octopus might be strongly linked to its trophic resources.

  7. Fisheries and reproductive biology of Octopus vulgaris (Mollusca: Cephalopoda in the Gulf of Alicante (Northwestern Mediterranean

    Directory of Open Access Journals (Sweden)

    M. GONZALEZ

    2012-12-01

    Full Text Available The common octopus Octopus vulgarisCuvier, 1797 is the most fished cephalopod species along the Spanish coasts. Its catches are highly fluctuating due to the short life cycle of the species and to the annual variability of the recruitment pattern, strongly dependent on the environmental conditions affecting the eggs and paralarvae. This study examines the common octopus fishery, the catch composition, and the main features of the reproductive biology of this species in the Gulf of Alicante (Spanish Eastern coast, Western Mediterranean FAO division 37.1.1. The common octopus fishery was studied analysing the monthly landing and effort data by fishing gear from 1994 to 2005. Monthly samplings of the commercial O. vulgarislandings from trawlers and clay pots from January 2004 to December 2005 resulted in the measuring of 1833 specimens to enable analysis of the catch composition, and allowed the biological sampling of 1176 individuals to provide the reproductive parameters of the species in the study area. The length-weight relationship calculated for the species was BW = 0.51 * DML 2.87. The yearly sex ratios (males:females were 1:1 (trawl, 2004, 1:0.74 (trawl, 2005, and 1:0.88 (clay pots, 2005. The size (dorsal mantle length, DML at maturity of the species in the study area was 9.67 cm for males and 14.38 cm for females. The gonadosomatic index reached a peak between April and July for males and in July for females. The Fulton condition index was lower in both sexes between June and September, and for males in November-December, whereas for both sexes the values of the digestive gland index were at their maximum between June and December. The energy allocation between somatic and reproductive growth was investigated and the results suggested that the energy spent on reproduction mainly came from feeding, and not from energy stored in the mantle tissues or in the digestive gland

  8. Food intake and growth in Macoma balthica (mollusca) in the laboratory

    Science.gov (United States)

    Hummel, H.

    Groups of Macoma balthica were kept during 4-week periods in an experimental set up at a constant temperature and food concentration. Food concentrations (expressed in particulate organic carbon) for the different groups ranged from 0 to 16 mg C·I -1. The experiment was repeated 6 times, viz. in different months, and the temperatures were changed accordingly to correspond with levels found in the field. The rates of food intake, water clearance and growth were followed throughout the experiment. The flagellate Isochrysis galbana served as food. With increasing food concentration all 3 rates (food intake, water clearance and growth) increased up to maximum to decrease again at high food concentrations. Such bell-shaped relationships were observed in all seasons. The dependence of growth on food concentration was similar in all seasons. Zero growth or weight losses were observed at food concentrations below 1.3 mg C·I -1, and maximum growth rates were reached at food concentrations between 5 and 7 mg C·I -1. The daily maintenance ration amounted to about 1.2% of the body weight. Seasonal differences were observed in the relationships of the rates of both water clearance and food intake with food concentration. During the winter and spring the optimum curves for these relationships reached their maximum at food concentrations of 8 to 10 mg C·I -1. During summer and early autumn the optimum curves were shifted to lower food concentrations, around 2 to 4 mg C·I -1, probably as an adaptation to low food concentrations observed in the field during these periods.

  9. What explains the invading success of the aquatic mud snail Potamopyrgus antipodarum (Hydrobiidae, Mollusca)?

    NARCIS (Netherlands)

    Alonso, A.; Castro-Diez, P.

    2008-01-01

    The spread of non-native species is one of the most harmful and least reversible disturbances in ecosystems. Species have to overcome several filters to become a pest (transport, establishment, spread and impact). Few studies have checked the traits that confer ability to overcome these steps in the

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

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    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.

  11. The Marine Mollusca of St. Martin, Lesser Antilles, collected by H.J. Krebs

    NARCIS (Netherlands)

    Coomans, H.E.

    1963-01-01

    In 1864 an anonymous list of species of the West Indian marine mollusks was published in Denmark. There were only twenty copies printed, seven of which were lost during transportation to the West Indies (CLENCH et al., 1947—1948, p. 23). The author was HENDRIK JOHANNES KREBS (1821—1907), Fig. 117, a

  12. Relationship between geographic distribution and morphological patterns in genus Cerion (Mollusca: Cerionidae in Cuba

    Directory of Open Access Journals (Sweden)

    Alejandro Rodríguez-Ochoa

    2014-04-01

    Full Text Available The genus Cerion, with 90 species described for Cuba, is highly polytypical and it had been litle studied. The idea of the absence of and spatiall arrage-ment of morphotypes had been mantained even knowing that in other distri-bution areas several patterns had arise. The goal of this paper was to charac-terize morphological variation on the Cuban species of Cerion and to assess relationship between geographic distances between populations and shell shape differences. Geometric morphometry was used in 812 individuals from 45 species to describe shell shapes, using procrustes dis-tances, centroide size and principal warps, keeping shell lenght as size measure. Morphological distances and size differences was correlated to geographic dis-tances using Mantel tests. Size show a weak correla-tion (-0.12 but morphological and geographic distanc-es was correlated (0.401. A morphological variation pattern was detected in the second principal warp, ordering geographic groups in a way consistent to clinal variation of shell shapes described to Cerion in the eastern region of Caribbean. All results reinforce the need of a taxonomic review of the genus in Cuba.

  13. Relationship between geographic distribution and morphological patterns in genus Cerion (Mollusca: Cerionidae) in Cuba

    OpenAIRE

    Alejandro Rodríguez-Ochoa

    2014-01-01

    The genus Cerion, with 90 species described for Cuba, is highly polytypical and it had been litle studied. The idea of the absence of and spatiall arrage-ment of morphotypes had been mantained even knowing that in other distri-bution areas several patterns had arise. The goal of this paper was to charac-terize morphological variation on the Cuban species of Cerion and to assess relationship between geographic distances between populations and shell shape differences. Geometric morphome...

  14. 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.

  15. 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.

  16. Dynamics, migration and growth of Nassarius reticulatus (Mollusca: Prosobranchia) colonizing saline Lake Grevelingen (SW Netherlands)

    Science.gov (United States)

    Lambeck, R. H. D.

    The marine snail Nassarius reticulatus colonized Lake Grevelingen after its creation in 1971. A population explosion took place in 1976. Dynamics, growth and biomass development were studied during 1976 and 1977. One generation a year was observed, with 1976 settlement around August 1. Densities at a 12 m deep station were mostly below 10 m -2, at two shallow (1 m) stations numbers increased to 40 to 60 m -2, as a result of immigration. Numbers at two 3 m stations, with peak values of 200 m -2, showed a cyclic pattern with a minimum in July 1977 due to migratory movements. Biomass increased over the period of investigation. A lowest maximum biomass was found at 12 m (0.16 g ADW m -2) and a highest of 5.0 g at a 3 m station. The lake average in April 1977 amounted to a value between 1.2 and 2.1 g ADW m -2. In this survey the dominant 1976 year class showed a gradual decline from ˜ 300 ind·m -2 between 2 and 3.5 m to ˜ 60 m -2 in water deeper than 10 m. Growth rates were also depth dependent. Within the range of 2 to 25 m juveniles born in 1976 showed a maximum mean size of 6.8 mm after one growing season at 5 to 6 m depth against only 3.6 mm in deep water. Highest mean values after 2 growing-seasons, viz. 16 mm, were reached at the 1 m deep stations, which figure might be inflated by size-dependent immigration. Growth was poor (8 mm) at the 12 m station. Growth rates are similar to Swedish observations, but were reached at 10 to 50 times higher densities in Lake Grevelingen.

  17. Cytogenetics of Anodonta cygnea (Mollusca: Bivalvia) as possible indicator of environmental adversity

    Science.gov (United States)

    Carrilho, J.; Leitão, A.; Vicente, C.; Malheiro, I.

    2008-11-01

    Anodonta cygnea is a freshwater clam, belonging to the Unionidae family, which can be found in rivers and lagoons all over Europe and Northern America. As they appear as important case studies for ecological damage assessments, the various species of the Unionidae family have been submitted to a sort of recent studies on their chromosomal or cytogenetic status. In this study we confirmed the diploid chromosome number of 2 n = 38 for this species, and established for the first time the karyotype, which comprised six metacentric, 12 submetacentric and one subtelocentric chromosome pairs. We also found a high percentage of cells with an abnormal number of chromosomes. Considering that karyotype disturbances in Unionids have been previously related with exposure to chemicals, either natural or produced by human activity, we determined the aneuploidy index for our population. The aneuploidy index is an excellent marker for pollutant presence/effect. The animals acclimatized in tap water and in natural water from the lake where the individuals were collected showed different levels of aneuploidy. The higher values were found in tap water. Chromosome analysis techniques seem a suitable tool to study the impact of contaminants referred above, and making A. cygnea a suitable organism for assessment of an eugenic damage in aquatic systems. On the other hand, our results also point out to the importance of doing the acclimatizing process of the collected animals in their own natural water.

  18. Fisheries and reproductive biology of Octopus vulgaris (Mollusca: Cephalopoda) in the Gulf of Alicante (Northwestern Mediterranean)

    OpenAIRE

    Gonzalez, M; E. BARCALA; J.L. PEREZ-GIL; M.N. CARRASCO; M. C. Garcia-Martinez

    2012-01-01

    The common octopus Octopus vulgarisCuvier, 1797 is the most fished cephalopod species along the Spanish coasts. Its catches are highly fluctuating due to the short life cycle of the species and to the annual variability of the recruitment pattern, strongly dependent on the environmental conditions affecting the eggs and paralarvae. This study examines the common octopus fishery, the catch composition, and the main features of the reproductive biology of this species in the Gulf of Alicante (S...

  19. A contribution to the knowledge of non-marine Mollusca of South West Africa

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1970-01-01

    The moment to collate scattered notes on South West African non-marine molluscs arrived last year when Mr. B. H. Lamoral of the Natal Museum, Pietermaritzburg (South Africa), entrusted the present author with the study of material obtained during a Council of Scientific and Industrial Research (C.S.

  20. Complete sequence and polymorphisms of female Ruditapes philippinarum (Mollusca: Bivalvia) mitochondria genome.

    Science.gov (United States)

    Hwang, Jae Yeon; Han, Geon Goo; Park, Jung Youn; Kim, Eun-Mi; An, Cheul Min; Kang, Jung-Ha; Choi, Yun-Jaie; Kim, Eun Bae

    2016-09-01

    Mitogenome of female Ruditapes philippinarum organism was sequenced, and genomic variation and phylogeny were examined in this study. Length of the mitogenome was 22 089 bp showing 94.28% of sequence identity with previously reported sequence. Total 707 single nucleotide polymorphisms, SNPs, were detected and 50 residues were non-synonymous SNPs among the 202 SNPs in protein-coding genes. Deleted genomic fragments with of 265 bp and 322 bp were observed in non-coding regions, ND2 to ND4L and ND4L to tRNA(Ile), respectively. Phylogenic analysis confirmed that used organisms were female R. philippinarum, and the species has closer evolutionary distance with genus Paphia rather than genus Meretrix. Our finding will be help to set an insight for population and evolutionary genomics of Veneroida clams as well as application to marine industry. PMID:26248000

  1. Neogene Mollusca from the Vogelkop (Bird's Head Peninsula), West Irian, New Guinea

    NARCIS (Netherlands)

    Beets, C.

    1986-01-01

    During a reconnaissance of the Tertiary formations in the western Vogelkop in 1929/1930 for the Bataafsche Petroleum Maatschappij, The Hague, the geologists J.P. Roothaan and J.B. Woolley collected a number of fossil molluscs in the outcrop area of the Klasaman Formation, later to be dated as 'Late

  2. 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.

  3. 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.

  4. [Mollusc diversity in an Arca zebra (Mollusca: Bivalvia) community, Chacopata, Sucre, Venezuela].

    Science.gov (United States)

    Prieto, A S; Ruiz, L J; García, N; Alvarez, M

    2001-06-01

    The diversity of a subtidal epifaunal mollusk community was studied from September, 1990 to September, 1991 in Chacopata, Sucre State, Venezuela. There were 40 species (24 bivalves and 16 gastropods). The diversity indexes (H' = 2.087, J' = 0.392, 1/D = 0.528) were low when compared with other tropical zones. Monthly diversity reached its maximum in September, 1990 (1.63 bits/ind.) and July, 1991 (1.60 bits/ind.); minimum diversity occurred in June, 1991 (0.52 bits/ind.). A Log series model applied to species abundance data showed a straight line with a diversity index alpha of 5.56. Of 40 species identified, the turkeywing Arca zebra was dominant (69% in number of individuals and 72% of biomass) followed by Pinctada imbricata, Modiolus squamosus, Chama macerophyla and Anadara notabilis. The predatory snails Phyllonotus pomum, Chicoreus brevifrons and Murex recurvirostris seemed to have trophic relationships with A. zebra. The total mean biomass in wet weight (469.20 +/- 263 g m-2, shell included) was high which indicates that A. zebra, a species with a rapid growth rate, occupies a central role in the assemblage as an efficient filter feeder that converts planktonic food into available biomass, supporting one of the most important fisheries in Venezuela. PMID:11935909

  5. 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. PMID:19218496

  6. [Growth of Octopus maya (Mollusca: Cephalopoda) of the Yucatan coast, Mexico: a long-term analysis].

    Science.gov (United States)

    Nepita Villanueva, M R; Defeo, O

    2001-03-01

    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 phi' 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 phi' 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 phi' 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. PMID:11795175

  7. Systematic value of the ultrastructure of the sucker surface in the squid family Mastigoteuthidae (Mollusca: Cephalopoda)

    NARCIS (Netherlands)

    Salcedo-Vargas, Mario Alejandro

    1995-01-01

    The ultrastructure of the sucker surface is described and its systematic value for mastigoteuthid squids, which bear minute suckers, is considered. An introduction to sucker terms is given and a redefinition of these terms is attempted. Using scanning electron microscopic data, two genera and four s

  8. Reproduction in Heteroteuthis dispar (Ruppell, 1844) (Mollusca : Cephalopoda): a sepiolid reproductive adaptation to an oceanic lifestyle

    NARCIS (Netherlands)

    Hoving, H. J. T.; Laptikhovsky, V.; Piatkowski, U.; Onsoy, B.; Oensoy, B.

    2008-01-01

    Small cephalopods of the genus Heteroteuthis are the most pelagic members in the family Sepiolidae. This study examines the reproductive biology of Heteroteuthis dispar (Ruppell, 1844), the first such study on any member of the genus, based on 46 specimens (27 females and 19 males) collected during

  9. Toxicological aspects associated with the ecology of Donax trunculus (Bivalvia, Mollusca) in a polluted environment

    International Nuclear Information System (INIS)

    This study provides data on the ecology and toxicology observed in the population of Donax trunculus, a sand dwelling mussel, in the shallow subtidal of Haifa Bay (Mediterranean Sea, Israel). The studied population of the mussel forms a dominant fraction in a community of sand-dwelling molluscs in a zone located 5-25 m from the shoreline, and at depths of 20-120 cm, numbering up to 2000 per m2. Samples of the mussel were collected from three sites, located within 9 km of shore in Haifa Bay. These included a clean site (Akko), a site polluted by a chemical PVC-polymer industry (Frutarom), and a site polluted with oil and waste from the petrochemical industry (Qiryat Yam). Metal analysis indicated site-dependent variations in levels of cadmium, lead, copper and mercury in the mussel soft tissues. Copper levels were similar in the bivalves collected from all the sites. Levels of mercury were significantly higher in specimens from the PVC-polluted site (Frutarom) while levels of cadmium were higher in Akko and Qiryat Yam compared to Frutarom. Lead residues were found only in Donax from Akko. The residual contents of mercury, copper and cadmium were relatively high in the young and noticeably low in Donax of medium body size. The main site of deposition of metals was in the soft tissues of the bivalve, but bioaccumulation of metals was also found in the shells. A marked increase in permeability of gills and mantle to the fluorescent anionic dye-fluorescein (FLU) was detected in Donax from Qiryat Yam and especially Frutarom, compared to the bivalves sampled from Akko. Multiple foci of enhanced permeability (multiple fluorescent spots) were detected in all the individuals sampled from Frutarom but none in the bivalve samples from Akko. Lysosomal accumulation of the metachromatic fluorescent cationic probe, acridine orange - (AO), was significantly decreased in the tissues of D. trunculus from polluted sites, especially polluted by the PVC factory. This decrease correlated with lysosomal enlargement and the formation of secondary lysosomes. D. trunculus appears to possess the most effective biochemical and physiological defense mechanisms enabling it to survive in habitats of polluted shallow waters, where other sand dwelling mollusc species were absent or found only in waters deeper then 2.5 m. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

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

    Directory of Open Access Journals (Sweden)

    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.

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

    NARCIS (Netherlands)

    H.H. Dijkstra; B.A. Marshall

    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

  12. 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 mus

  13. 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.

  14. Taxonomic implications of molecular studies on Northern Brazilian Teredinidae (Mollusca: Bivalvia) specimens

    OpenAIRE

    Sonia Maria Lima Santos; Claudia Helena Tagliaro; Colin Robert Beasley; Horacio Schneider; Iracilda Sampaio; Carlos Santos Filho; Ana Cláudia de Paula Müller

    2005-01-01

    The current taxonomy of the Teredinidae (shipworms) is wholly based on morphology and up to now no molecular studies of the phylogeny of this group have been published. In the present study the relationships between four genera of the subfamilies Teredininae and Bankiinae were established and the efficiency of the 16S rRNA gene in characterizing four Teredinidae species was tested. Phylogenetic trees support the grouping of Bankia fimbriatula with Nausitora fusticula and of Neoteredo reynei w...

  15. Clarifying phylogenetic relationships and the evolutionary history of the bivalve order Arcida (Mollusca: Bivalvia: Pteriomorphia).

    Science.gov (United States)

    Combosch, David J; Giribet, Gonzalo

    2016-01-01

    The systematics of the bivalve order Arcida constitutes an unresolved conundrum in bivalve systematics. The current definition of Arcida encompasses two superfamilies: Limopsoidea, which includes the recent families Philobryidae and Limopsidae, and Arcoidea, which encompasses the families Arcidae, Cucullaeidae, Noetiidae, Glycymerididae and Parallelodontidae. This classification, however, is controversial particularly with respect to the position and taxonomic status of Glycymerididae. Previous molecular phylogenies were limited either by the use of only a single molecular marker or by including only a few limopsoid and glycymeridid taxa. The challenging nature of Arcida taxonomy and the controversial results of some of the previous studies, prompted us to use a broad range of taxa (55 species), three nuclear markers (18S rRNA, 28S rRNA and histone H3) and a wide range of algorithmic approaches. This broad but stringent approach led to a number of results that differ significantly from previous studies. We provide the first molecular evidence that supports the separation of Arcoidea from Limopsoidea, although the exact position of Glycymerididae remains unresolved, and the monophyly of Limopsoidea is algorithm-dependent. In addition, we present the first time-calibrated evolutionary tree of Arcida relationships, indicating a significant increase in the diversification of arcidan lineages at the beginning of the Cretaceous, around 140Ma. The monophyly of Arcida, which has been supported previously, was confirmed in all our analyses. Although relationships among families remain somehow unresolved we found support for the monophyly of most arcidan families, at least under some analytical conditions (i.e., Glycymerididae, Noetiidae, Philobryidae, and Limopsidae). However, Arcidae, and particularly Arcinae, remain a major source of inconsistency in the current system of Arcida classification and are in dire need of taxonomic revision.

  16. The Marine Mollusca of Suriname (Dutch Guiana) Holocene and recent Part II. Bivalvia and Scaphopoda

    NARCIS (Netherlands)

    Regteren Altena, van C.O.

    1971-01-01

    "The student must know something of systematic work. This is populary supposed to be a dry-as-dust branch of zoology. In fact, the systematist may be called the dustman of biology, for he performs a laborious and frequently thankless task for his fellows, and yet it is one which is essential for the

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

    OpenAIRE

    Tëmkin Ilya

    2010-01-01

    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 tr...

  18. Complete sequence and polymorphisms of female Ruditapes philippinarum (Mollusca: Bivalvia) mitochondria genome.

    Science.gov (United States)

    Hwang, Jae Yeon; Han, Geon Goo; Park, Jung Youn; Kim, Eun-Mi; An, Cheul Min; Kang, Jung-Ha; Choi, Yun-Jaie; Kim, Eun Bae

    2016-09-01

    Mitogenome of female Ruditapes philippinarum organism was sequenced, and genomic variation and phylogeny were examined in this study. Length of the mitogenome was 22 089 bp showing 94.28% of sequence identity with previously reported sequence. Total 707 single nucleotide polymorphisms, SNPs, were detected and 50 residues were non-synonymous SNPs among the 202 SNPs in protein-coding genes. Deleted genomic fragments with of 265 bp and 322 bp were observed in non-coding regions, ND2 to ND4L and ND4L to tRNA(Ile), respectively. Phylogenic analysis confirmed that used organisms were female R. philippinarum, and the species has closer evolutionary distance with genus Paphia rather than genus Meretrix. Our finding will be help to set an insight for population and evolutionary genomics of Veneroida clams as well as application to marine industry.

  19. Phylogeny and evolution of ontogeny of the family Oxytomidae Ichikawa, 1958 (Mollusca: Bivalvia)

    Science.gov (United States)

    Lutikov, O. A.; Temkin, I. E.; Shurygin, B. N.

    2010-08-01

    We described ontogenies and reconstructed morphogeneses of hinges in some supraspecific taxa of the bivalve family Oxytomidae Ichikawa, 1958 from the Mesozoic of Russia. The phylogeny of the family is reconstructed using evolutionary and cladistic methods. The appearance of the endemic genus Arctotis Bodylevsky, 1960 in the epicontinental seas of Siberia can be explained in terms of gradual transformations of the ligament and byssal apparatus in the Northern Siberian members of Praemeleagrinella Lutikov et Shurygin, 2009 and Praearctotis Lutikov et Shurygin, 2009.

  20. On the identity of broad-shelled mussels (Mollusca, Bivalvia, Mytilus) from the Dutch delta region

    NARCIS (Netherlands)

    Groenenberg, D.S.J.; Wesselingh, F.P.; Rajagopal, S.; Jansen, J.M.; Bos, M.M.; Velde, van der G.; Gittenberger, E.; Hoeksema, B.W.; Raad, H.; Hummel, H.

    2011-01-01

    Late Quaternary (Eemian) deposits of the Netherlands contain shells that resemble those of living Mytilus galloprovincialis. Similar broad-shelled mytilids also occur in estuaries of the southwestern Netherlands together with slender individuals typical of M. edulis. We sampled living mussels along

  1. 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. bitru

  2. Size-differential feeding in Pinna nobilis L. (Mollusca: Bivalvia): Exploitation of detritus, phytoplankton and zooplankton

    Science.gov (United States)

    Davenport, John; Ezgeta-Balić, Daria; Peharda, Melita; Skejić, Sanda; Ninčević-Gladan, Živana; Matijević, Slavica

    2011-04-01

    The endangered fan shell Pinna nobilis is a large bivalve mollusc (animals has implications for future trophic studies of this endangered species. This study also provides the first demonstration of predation on zooplankton by P. nobilis.

  3. Thyasira ockelmanni (Mollusca: Bivalvia: Veneroidea, A new species of Thyasiridae from the Norwegian Sea

    Directory of Open Access Journals (Sweden)

    Rozemarijn Keuning

    2010-12-01

    Full Text Available 800x600 Normal 0 21 false false false NO-BOK X-NONE X-NONE MicrosoftInternetExplorer4 A new species of Thyasiridae, Thyasira ockelmanni n.sp. is described from the abyssal depths of the Norwegian Sea. The generic assignment is tentative and possible alternatives are discussed. The new species has some resemblance to Thyasira subovata (Jeffreys, 1881 and Adontorhina similis Barry & McCormack, 2007, but the posterior outline is rounded and not angulate or truncate as in these species.

  4. Taxonomic implications of molecular studies on Northern Brazilian Teredinidae (Mollusca: Bivalvia specimens

    Directory of Open Access Journals (Sweden)

    Sonia Maria Lima Santos

    2005-03-01

    Full Text Available The current taxonomy of the Teredinidae (shipworms is wholly based on morphology and up to now no molecular studies of the phylogeny of this group have been published. In the present study the relationships between four genera of the subfamilies Teredininae and Bankiinae were established and the efficiency of the 16S rRNA gene in characterizing four Teredinidae species was tested. Phylogenetic trees support the grouping of Bankia fimbriatula with Nausitora fusticula and of Neoteredo reynei with Psiloteredo healdi, but the genetic distances do not justify the classification of these species into two distinct subfamilies. The results show that B. fimbriatula, N. reynei and P. healdi specimens from the coast of the Brazilian state of Pará have five distinct 16S rRNA haplotypes, with one N. reynei haplotype differing from the other haplotypes in respect to at least seven sequences sites, indicating the existence of two very distinct sympatric lineages.

  5. Sinanodonta woodiana (Mollusca: Bivalvia: Unionidae: Isolation and Characterization of the First Microsatellite Markers

    Directory of Open Access Journals (Sweden)

    Elena Iulia Iorgu

    2011-08-01

    Full Text Available Sinanodonta woodiana (Lea, 1834 is a large Unionid species with a real invasion success. It colonized Europe, Central America, the Indonesian Islands and recently North America. The species life cycle involves a larval parasitic stage on freshwater fish species which contributes to the spread of the mussel. In this paper we describe, for the first time, eight polymorphic microsatellite loci for the species Sinanodonta woodiana. The genetic screening of individuals confirmed that all loci were highly polymorphic. The number of alleles per locus ranged from 7 to 14 and the observed heterozygosity ranged from 0.650 to 0.950. These loci should prove useful to study the species population genetics which could help to infer important aspects of the invasion process.

  6. Toxicological aspects associated with the ecology of Donax trunculus (Bivalvia, Mollusca) in a polluted environment

    Energy Technology Data Exchange (ETDEWEB)

    Fishelson, L.; Manelis, R. [Department of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv (Israel); Bresler, V.; Zuk-Rimon, Z.; Dotan, A.; Yawetz, A. [Institute for Nature Conservation Research, Faculty of Life Sciences, Tel Aviv University, Tel Aviv (Israel); Hornung, H. [Israel Oceanographic and Limnological Research, National Institute of Oceanography, Haifa (Israel)

    1999-02-09

    This study provides data on the ecology and toxicology observed in the population of Donax trunculus, a sand dwelling mussel, in the shallow subtidal of Haifa Bay (Mediterranean Sea, Israel). The studied population of the mussel forms a dominant fraction in a community of sand-dwelling molluscs in a zone located 5-25 m from the shoreline, and at depths of 20-120 cm, numbering up to 2000 per m{sup 2}. Samples of the mussel were collected from three sites, located within 9 km of shore in Haifa Bay. These included a clean site (Akko), a site polluted by a chemical PVC-polymer industry (Frutarom), and a site polluted with oil and waste from the petrochemical industry (Qiryat Yam). Metal analysis indicated site-dependent variations in levels of cadmium, lead, copper and mercury in the mussel soft tissues. Copper levels were similar in the bivalves collected from all the sites. Levels of mercury were significantly higher in specimens from the PVC-polluted site (Frutarom) while levels of cadmium were higher in Akko and Qiryat Yam compared to Frutarom. Lead residues were found only in Donax from Akko. The residual contents of mercury, copper and cadmium were relatively high in the young and noticeably low in Donax of medium body size. The main site of deposition of metals was in the soft tissues of the bivalve, but bioaccumulation of metals was also found in the shells. A marked increase in permeability of gills and mantle to the fluorescent anionic dye-fluorescein (FLU) was detected in Donax from Qiryat Yam and especially Frutarom, compared to the bivalves sampled from Akko. Multiple foci of enhanced permeability (multiple fluorescent spots) were detected in all the individuals sampled from Frutarom but none in the bivalve samples from Akko. Lysosomal accumulation of the metachromatic fluorescent cationic probe, acridine orange - (AO), was significantly decreased in the tissues of D. trunculus from polluted sites, especially polluted by the PVC factory. This decrease correlated with lysosomal enlargement and the formation of secondary lysosomes. D. trunculus appears to possess the most effective biochemical and physiological defense mechanisms enabling it to survive in habitats of polluted shallow waters, where other sand dwelling mollusc species were absent or found only in waters deeper then 2.5 m. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. GENETIC DIVERSITY OF FIVE FRESHWATER MUSSELS IN GENUS ANODONTA (MOLLUSCA: BIVALVIA) REVEALED BY RAPD ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Unionidae(Bivalvia)are distributed infreshwaters,and represent a significanttaxonof benthic community[1].In China,freshwater mussels are abundant resources[2].Since1949,substantial investigations onthe unionidfau-na had been undertakenin China[3—8].Withreference tooverseas research[9,10],a preliminary reorganization onthe Unionidae was performed accordingtosome classifica-tion characteristics such as shell shape,larvae character-istics,and breeding habit[11].Due tothe serious conver-gence of freshwater muss...

  8. Results of the Rumphius Biohistorical Expedition to Ambon : Part 6. Mollusca, Bivalvia, Pectinidae

    NARCIS (Netherlands)

    Dijkstra, H.H.

    1997-01-01

    During the Rumphius Biohistorical Expedition (1990) to Ambon 17 Pectinidae species were collected, nine of which were described by Rumphius (1705) and five illustrated by Rumphius. One species, viz. Decatopecten plica (Linnaeus, 1758), illustrated in Rumphius (1705: pl. 44, fig. O), has not been ref

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

    Directory of Open Access Journals (Sweden)

    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.

  10. A new type of symbiosis: Heterocyathus japonicus (Cnidaria: Scleractinia) living on Fissidentalium vernedei (Mollusca: Scaphopoda)

    NARCIS (Netherlands)

    Zibrowius, H.

    1998-01-01

    After introductory remarks on the solitary coral genera Heterocyathus and Heteropsammia, commonly known to be symbiotic with a sipunculan inhabiting a gastropod shell, Heterocyathus japonicus is redescribed in detail. It occurs from Taiwan to northern Honshu, Japan. It is the first of these symbioti

  11. ACUTE TOXICITY OF MERCURY TO EMBRYOS OF Helisoma trivolvis (SAY, 1817 (MOLLUSCA: PLANORBIDAE

    Directory of Open Access Journals (Sweden)

    Passuni, G.

    2008-01-01

    Full Text Available Mercury is a metal very employed at industry and mining in Peru. The aim of current research was to determine embryotoxic lethal acute toxicity of Hg2+, in form of chloride of mercury (HgCl on 2 Helisoma trivolvis (Say, 1817 at 24 h exposure. Concentrations assayed were 514, 51.4, 5.14 and 0.51 ug Hg2+ L-1, since salt on base of HgCl using dechlorined water as diluents. Snail embryos 2 were considered dead when none rotation movement during since 30 seconds. Percentage of mortality of embryonic stages of H. trivolvis increased with each of concentrations crescents of Hg2+ at 24 h exposure. At a concentration of 514.4 ug Hg2+ L-1 was observed significantly differences in relation to control. Moreover, concentration of 514.4 ug Hg2+ L-1 showed differences with relation to other three treatments. LC was 2.49 ug Hg2+ L-1. Embryos of H. trivolvis were 50 higher sensible to Hg2+ in comparison to other freshwater snail species was concluded.

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

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    M. ANTIT

    2012-12-01

    Full Text Available The occurrences of non-indigenous marine molluscs in Tunisia are reviewed, based booth on a literature survey and on original material. Species are accepted as established if there are two independent reports, either geographically separate or at least one month apart in time. On these grounds, 14 species are accepted (12 alien and 2 expanding their range from elsewhere in the Mediterranean, 3 aliens need confirmation but are likely to meet the standards for acceptation on a short future, and 5 records are rebutted or questioned. Two more species may be considered as cryptogenic, the reports are reliable but it is not clear indication that they are not indigenous. Two of the alien species are reported for the first time in Tunisian waters: the nudibranch Polycerella emertoni qualifies as established, and the bivalve Anadara transversa is tentatively identified from a juvenile live-taken specimen, which awaits further confirmation.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.

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

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    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.

  14. Redescription of Dicyemennea nouveli (Phylum: Dicyemida) from Enteroctopus dofleini (Mollusca: Cephalopoda: Octopoda).

    Science.gov (United States)

    Furuya, Hidetaka

    2008-10-01

    A species of dicyemid mesozoan is redescribed from the giant Pacific octopus, Enteroctopus dofleini (Wülker, 1910), collected off Iwase in Toyama Bay, Honshu, Japan. Dicyemennea nouveli McConnaughey, 1959, is a large species that reaches about 12,000 microm in length. This species lives in folds of the renal appendages. The vermiform stages are characterized as having 30-41 peripheral cells, a conical calotte, and an axial cell that extends to the middle of the metapolar cells. An anterior abortive axial cell is present in vermiform embryos. Full-grown vermiform embryos have as many as 4 agametes. Infusoriform embryos consist of 39 cells; 2 nuclei are present in each urn cell and the refringent bodies are solid. PMID:18576827

  15. Phylogenetic relationships among major species of japanese coleoid cephalopods (Mollusca: Cephalopoda) using three mitochondrial DNA sequences.

    Science.gov (United States)

    Takumiya, Mikio; Kobayashi, Mari; Tsuneki, Kazuhiko; Furuya, Hidetaka

    2005-02-01

    Phylogenetic relationships among 36 species of major coleoid cephalopods from Japanese waters were studied using partial sequences of three mitochondrial genes, 16S rDNA, 12S rDNA, and cytochrome c oxidase subunit I gene. Octopoda and Decapoda were monophylic groups. Within Sepioidea, Sepiadariidae and Sepiolidae were not closely related to Sepiidae, but rather related to Teuthoidea. Sepiidae with a distinct calcareous shell formed a single cluster. Myopsida was closely related to Oegopsida. Within Octopoda, Opisthoteuthis depressa and Argonauta argo diverged earlier than Octopodiidae. The common octopuses in Japanese waters were separated into three clusters. The first cluster occupied a basal position, and includes large-sized octopuses, such as Enteroctopus dofleini and Octopus (Paroctopus) conispadiceus from the continental shelf and upper slope. The second cluster consisted of long-armed octopuses, such as O. ornatus, O. minor, and O. sasakii. The third cluster contained small- to medium-sized octopus, such as Amphioctopus fangsiao, A. areolatus, O. cyaneus, and O. vulgaris, in which several species possess ocelli on the web. The second cluster formed the sister group to the third cluster. PMID:15738635

  16. The cytoskeleton of chondrocytes of Sepia officinalis (Mollusca, Cephalopoda: an immunocytochemical study

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    F Leone

    2009-06-01

    Full Text Available Our previous electron microscope study showed that chondrocytes from cephalopod cartilage possess a highly developed cytoskeleton and numerous cytoplasmic processes that ramify extensively through the tissue. We have now carried out a light microscope immunocytochemical study of chondrocytes from the orbital cartilage of Sepia officinalis to obtain indications as to the nature of the cytoskeletal components. We found clear positivity to antibodies against mammalian tubulin, vimentin, GFAP, and actin, but not keratin. The simultaneous presence of several cytoskeletal components is consistent with the hypothesis that cephalopod chondrocytes have the characteristics of both chondrocytes and osteocytes of vertebrates, which endow the tissue as a whole with some of the properties of vertebrate bone. We confirm, therefore, the presence in molluscs of the ubiquitous cytoskeletal proteins of metazoan cells that have remained highly conserved throughout phylogenetic evolution.

  17. Seasonal variations in biochemical composition of Sepia officinalis (Mollusca) from the Mediterranean waters off Alexandria, Egypt

    Energy Technology Data Exchange (ETDEWEB)

    El-Sayed, A.M.; Halim, Y. [Alexandria, Univ. (Egypt). Faculty of Science. Oceanography Dept.; Riad, R. [National Inst. of Oceanography and Fisheries, Kayet Bay, Alexandria (Egypt)

    1995-12-31

    The biochemical compositions of 465 Sepia officinalis mantles from the Mediterranean waters off Alexandria Egypt, were studied from September 1989 to August 1990. Water contents of males and females were not significantly different, and followed the same pattern showing a sharp decrease in summer. Lipid contents of males and females were similar, showing two peaks in summer and autumn. A clear reverse relationship between water and lipid contents was found. Protein and ash contents showed irregular patterns. Protein contents were increased in early spring and mid-summer. The relationship between body compositions and mantle size, gonads maturation and environmental conditions was discussed.

  18. A tropical Atlantic species of Melibe Rang, 1829 (Mollusca, Nudibranchia, Tethyiidae

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    Erika Espinoza

    2013-07-01

    Full Text Available A new species of Melibe is described based on two specimens collected in Florida. This new species is well differentiated morphologically and genetically from other species of Melibe studied to date. The four residue deletions in the cytochrome c oxidase subunit 1 protein found in all previously sequenced tropical species of Melibe sequenced (and Melibe rosea are also present in this new species. These deletions do not appear to affect important structural components of this protein but might have fitness implications. This paper provides the first confirmed record of Melibe in the tropical western Atlantic Ocean.

  19. Systematic value of the ultrastructure of the sucker surface in the squid family Mastigoteuthidae (Mollusca: Cephalopoda)

    OpenAIRE

    Salcedo-Vargas, Mario Alejandro

    1995-01-01

    The ultrastructure of the sucker surface is described and its systematic value for mastigoteuthid squids, which bear minute suckers, is considered. An introduction to sucker terms is given and a redefinition of these terms is attempted. Using scanning electron microscopic data, two genera and four subgenera of Mastigoteuthidae from the Northwest Pacific are distinguished. The presence of “cushions” in the sucker is discussed and considered as a character important for understanding adaptation...

  20. 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

    Combined electron microscopy and immunocytochemistry of the larvae of several polyplacophoran species (Chiton olivaceus, Lepidochitona aff. corrugata, Mopalia muscosa) revealed a sensory system new to science, a so-called "ampullary system." The cells of the "ampullary system" are arranged in four...... sensory organs of other molluscs, such as the apical complex of gastropod and bivalve larvae, osphradia of vetigastropods, and olfactory organs of cephalopods, and nuchal organs of certain polychaetes. The ampullary cells and their nerves are densely stained by anti-FMRF-amide fluorescence dyes, whereas...... antiserotonin staining is only weak. While cytological homology of the ampullary cells with those of other organs is probable, the ampullary system as a whole is regarded as a synapomorphy of the Polyplacophora or Chitonida....

  1. The Continuing Debate on Deep Molluscan Phylogeny: Evidence for Serialia (Mollusca, Monoplacophora + Polyplacophora

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    I. Stöger

    2013-01-01

    Full Text Available Molluscs are a diverse animal phylum with a formidable fossil record. Although there is little doubt about the monophyly of the eight extant classes, relationships between these groups are controversial. We analysed a comprehensive multilocus molecular data set for molluscs, the first to include multiple species from all classes, including five monoplacophorans in both extant families. Our analyses of five markers resolve two major clades: the first includes gastropods and bivalves sister to Serialia (monoplacophorans and chitons, and the second comprises scaphopods sister to aplacophorans and cephalopods. Traditional groupings such as Testaria, Aculifera, and Conchifera are rejected by our data with significant Approximately Unbiased (AU test values. A new molecular clock indicates that molluscs had a terminal Precambrian origin with rapid divergence of all eight extant classes in the Cambrian. The recovery of Serialia as a derived, Late Cambrian clade is potentially in line with the stratigraphic chronology of morphologically heterogeneous early mollusc fossils. Serialia is in conflict with traditional molluscan classifications and recent phylogenomic data. Yet our hypothesis, as others from molecular data, implies frequent molluscan shell and body transformations by heterochronic shifts in development and multiple convergent adaptations, leading to the variable shells and body plans in extant lineages.

  2. Redescription of Hiatella meridionalis d'Orbigny, 1846 (Mollusca, Bivalvia, Hiatellidae from Argentina

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    Luiz Ricardo L. Simone

    2008-01-01

    Full Text Available The redescription of Hiatella meridionalis (d’Orbigny, 1846 is provided as first attempt to improve the systematics of the genus in the regions of Atlantic and western Pacific. This reanalysis is based on specimens collected in the vicinity of the type localities and is based on detailed morphology of samples that some researches consider a single, wide ranging species. From the morphological characters, the more interesting are: a high quantity of papillae at incurrent siphon; the retractor muscles of siphon divided in two bundles; the small size of the palps; the muscular ring in the stomach; and the zigzag fashion of the short intestinal loops. These characters distinguish the species from the other hiatellids so far examined. Type material of the species was examined, by first time illustrated, and the lectotype is designated.A redescrição de Hiatella meridionalis (d’Orbigny, 1846 é realizada como primeiro passo na melhoria da sistemática do gênero das regiões atlântica e pacífica oeste. Esta re-análise é baseada em espécimes coletados nas vizinhanças da localidade tipo e em morfologia detalhada de amostras que alguns pesquisadores consideram pertencer a uma única espécie de ampla distribuição. Dos caracteres anatômicos, os mais interessantes são: uma grande quantidade de papilas no sifão inalante; o músculo retrator dos sifões dividido em duas porções; o tamanho pequeno dos palpos; um anel muscular transversal no estomago; e um padrão em zigzag no curto intestino. Estes caracteres distinguem a espécie dos demais hiatelídeos até então examinados. Os sintipos da espécie foram também examinados e pela primeira vez ilustrados; o lectótipo é designado.

  3. p63 in Mytilus galloprovincialis and p53 family members in the phylum Mollusca.

    Science.gov (United States)

    Stifanić, Mauro; Micić, Milena; Ramsak, Andreja; Blasković, Sanja; Ruso, Ana; Zahn, Rudolf K; Batel, Renato

    2009-11-01

    Genes of the p53 family are known to be critical regulators of the cell cycle. They have already been established as possible biomarkers. Elaborate regulation mechanisms result in numerous cDNA and protein isoforms being expressed from each gene of the p53 family. Their similarity caused an often misleading nomenclature in non-vertebrate species. The aim of the present work is a clarification of the nomenclature of molluscan p53 family sequences, an essential prerequisite for reliable interpretation of gene expression and protein function studies. Here, we report five partial cDNA and one partial genomic p63 sequences, all originating from two Mytilus galloprovincialis individuals. DNA, deduced protein sequences, and the exon/intron architecture were analyzed and compared to p53, p63 and p73 sequences from other organisms. Along with our sequences, we analyzed all similar molluscan sequences found in the GenBank database. The analysis showed our cDNA sequences code for the TAp63gamma isoform of the p63 protein, and identified all other molluscan p53 family sequences as p63 genes or their expression isoforms. Our results also indicate p63 as the ancestral gene of the p53 family as well as the only gene of the family present in non-chordate metazoan species.

  4. The Gastropods of Lake Eğirdir

    OpenAIRE

    YILDIRIM, Mehmet Zeki

    2004-01-01

    The Gastropoda species and its distribution was investigated in Lake Eğirdir. It was determined that 5 species belonging to Gastropoda, order Prosobranchia (Theodoxus heldreichi, Valvata naticina, Graecoanatolica lacustristurca, Falsipyrgula pfeiferi and Bithynia pseudemmericia) and 7 species belonging to the order Pulmonata (Radix peregra, Stagnicola palustris, Physa fontinalis, Physa acuta, Planorbis planorbis, Planorbis carinatus and Gyraulus albus) were present. Gastropoda species from 9 ...

  5. Evolution of poecilogony from planktotrophy: cryptic speciation, phylogeography, and larval development in the gastropod genus Alderia.

    Science.gov (United States)

    Ellingson, Ryan A; Krug, Patrick J

    2006-11-01

    Poecilogony, a rare phenomenon in marine invertebrates, occurs when alternative larval morphs differing in dispersal potential or trophic mode are produced from a single genome. Because both poecilogony and cryptic species are prevalent among sea slugs in the suborder Sacoglossa (Gastropoda: Opisthobranchia), molecular data are needed to confirm cases of variable development and to place them in a phylogenetic context. The nominal species Alderia modesta produces long-lived, feeding larvae throughout the North Atlantic and Pacific, but in California can also produce short-lived larvae that metamorphose without feeding. We collected morphological, developmental, and molecular data for Alderia from 17 sites spanning the eastern and western Pacific and North Atlantic. Estuaries south of Bodega Harbor, California, contained a cryptic species (hereafter Alderia sp.) with variable development, sister to the strictly planktotrophic A. modesta. The smaller Alderia sp. seasonally toggled between planktotrophy and lecithotrophy, with some individuals differing in development but sharing mitochondrial DNA haplotypes. The sibling species overlapped in Tomales Bay, California, but showed no evidence of hybridization; laboratory mating trials suggest postzygotic isolation has arisen. Intra- and interspecific divergence times were estimated using a molecular clock calibrated with geminate sacoglossans. Speciation occurred about 4.1 million years ago during a major marine radiation in the eastern Pacific, when large inland embayments in California may have isolated ancestral populations. Atlantic and Pacific A. modesta diverged about 1.7 million years ago, suggesting trans-Arctic gene flow was interrupted by Pleistocene glaciation. Both Alderia species showed evidence of late Pleistocene population expansion, but the southern Alderia sp. likely experienced a more pronounced bottleneck. Reduced body size may have incurred selection against obligate planktotrophy in Alderia sp. by

  6. Evolution of gastropod mitochondrial genome arrangements

    Directory of Open Access Journals (Sweden)

    Zardoya Rafael

    2008-02-01

    . dolabrata nor Pulmonata (polyphyletic nor Opisthobranchia (because of the inclusion S. pectinata were recovered as monophyletic groups. The gene order of the Vetigastropoda might represent the ancestral mitochondrial gene order for Gastropoda and we propose that at least three major rearrangements have taken place in the evolution of gastropods: one in the ancestor of Caenogastropoda, another in the ancestor of Patellogastropoda, and one more in the ancestor of Heterobranchia.

  7. Functional chloroplasts in metazoan cells - a unique evolutionary strategy in animal life

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    Krug Patrick J

    2009-12-01

    Full Text Available Abstract Background Among metazoans, retention of functional diet-derived chloroplasts (kleptoplasty is known only from the sea slug taxon Sacoglossa (Gastropoda: Opisthobranchia. Intracellular maintenance of plastids in the slug's digestive epithelium has long attracted interest given its implications for understanding the evolution of endosymbiosis. However, photosynthetic ability varies widely among sacoglossans; some species have no plastid retention while others survive for months solely on photosynthesis. We present a molecular phylogenetic hypothesis for the Sacoglossa and a survey of kleptoplasty from representatives of all major clades. We sought to quantify variation in photosynthetic ability among lineages, identify phylogenetic origins of plastid retention, and assess whether kleptoplasty was a key character in the radiation of the Sacoglossa. Results Three levels of photosynthetic activity were detected: (1 no functional retention; (2 short-term retention lasting about one week; and (3 long-term retention for over a month. Phylogenetic analysis of one nuclear and two mitochondrial loci revealed reciprocal monophyly of the shelled Oxynoacea and shell-less Plakobranchacea, the latter comprising a monophyletic Plakobranchoidea and paraphyletic Limapontioidea. Only species in the Plakobranchoidea expressed short- or long-term kleptoplasty, most belonging to a speciose clade of slugs bearing parapodia (lateral flaps covering the dorsum. Bayesian ancestral character state reconstructions indicated that functional short-term retention arose once in the last common ancestor of Plakobranchoidea, and independently evolved into long-term retention in four derived species. Conclusion We propose a sequential progression from short- to long-term kleptoplasty, with different adaptations involved in each step. Short-term kleptoplasty likely arose as a deficiency in plastid digestion, yielding additional energy via the release of fixed carbon

  8. The endocrine disruptor effect of the herbicides atrazine and glyphosate on Biomphalaria alexandrina snails.

    Science.gov (United States)

    Omran, Nahla Elsayed; Salama, Wesam Mohamed

    2016-04-01

    Atrazine (AZ) and glyphosate (GL) are herbicides that are widely applied to cereal crops in Egypt. The present study was designed to investigate the response of the snailBiomphalaria alexandrina(Mollusca: Gastropoda) as a bioindicator for endocrine disrupters in terms of steroid levels (testosterone (T) and 17β-estradiol (E)), alteration of microsomal CYP4501B1-like immunoreactivity, total protein (TP) level, and gonadal structure after exposure to sublethal concentrations of AZ or GL for 3 weeks. In order to study the ability of the snails' recuperation, the exposed snails were subjected to a recovery period for 2 weeks. The results showed that the level of T, E, and TP contents were significantly decreased (p ≤ 0.05) in both AZ- and GL-exposed groups compared with control (unexposed) group. The level of microsomal CYP4501B1-like immunoreactivity increased significantly (p ≤ 0.05) in GL- and AZ-exposed snails and reach nearly a 50% increase in AZ-exposed group. Histological investigation of the ovotestis showed that AZ and GL caused degenerative changes including azoospermia and oocytes deformation. Interestingly, all the recovered groups did not return back to their normal state. It can be concluded that both herbicides are endocrine disrupters and cause cellular toxicity indicated by the decrease of protein content and the increase in CYP4501B1-like immunoreactivity. This toxicity is irreversible and the snail is not able to recover its normal state. The fluctuation of CYP4501B1 suggests that this vertebrate-like enzyme may be functional also in the snail and may be used as a biomarker for insecticide toxicity.

  9. Spatial distribution and abundance of the megabenthic fauna community in Gabes gulf (Tunisia, eastern Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    H. EL LAKHRACH

    2012-12-01

    Full Text Available The aim of this paper is to bring to light the knowledge of marine diversity of invertebrates in Gabes gulf. The spatial distribution of the megabenthic fauna community in Gabes gulf (Tunisia, Eastern Mediterranean Sea, together with the bottom type and vegetation cover, were studied. The abundance of the megabenthic fauna was represented by eight groups: Echinodermata (38%, Crustacea (21%, Tunicata (19%, Mollusca (13%, Porifera (4%, Cnidaria (3%, Bryozoa, and Annelida (2%. It was spatially more concentrated in the coast area of the gulf than in the offshore waters. This area, especially, in Southern Kerkennah, North-est of Gabes and North-east of Djerba appeared to be in a good ecological condition  hosting a variety of species like the paguridsPaguristes eremita and Pagurus cuanensis, the brachyura Medorippe lanata, Inachus doresttensis, the Gastropoda Hexaplex trunculus, Bolinus brandaris, Aporrhais pespelecani, andErosaria turdus, the Bivalvia Fulvia fragilis, the Echinoidea Psammechinus microtuberculatus, Holothuria polii,Ophiothrix fragilis and Antedon mediterranea, and the AscidiaceaAplidium cf. conicum, Didemnum spp, and Microcosmus exasperatus.The species’ compositions of the megabentic fauna community showed clearly that the spatial analysis represented the differences between the community of these two regions (inshore waters and offshore waters. These differences were closely related to peculiar characters of the fauna and biotopes (depth, bottom type and vegetation cover community. The results of the present study should be considered as a necessary starting point for a further analysis of priceless benthic fauna contribution to the marine environment and its organisms.

  10. The endocrine disruptor effect of the herbicides atrazine and glyphosate on Biomphalaria alexandrina snails.

    Science.gov (United States)

    Omran, Nahla Elsayed; Salama, Wesam Mohamed

    2016-04-01

    Atrazine (AZ) and glyphosate (GL) are herbicides that are widely applied to cereal crops in Egypt. The present study was designed to investigate the response of the snailBiomphalaria alexandrina(Mollusca: Gastropoda) as a bioindicator for endocrine disrupters in terms of steroid levels (testosterone (T) and 17β-estradiol (E)), alteration of microsomal CYP4501B1-like immunoreactivity, total protein (TP) level, and gonadal structure after exposure to sublethal concentrations of AZ or GL for 3 weeks. In order to study the ability of the snails' recuperation, the exposed snails were subjected to a recovery period for 2 weeks. The results showed that the level of T, E, and TP contents were significantly decreased (p≤ 0.05) in both AZ- and GL-exposed groups compared with control (unexposed) group. The level of microsomal CYP4501B1-like immunoreactivity increased significantly (p≤ 0.05) in GL- and AZ-exposed snails and reach nearly a 50% increase in AZ-exposed group. Histological investigation of the ovotestis showed that AZ and GL caused degenerative changes including azoospermia and oocytes deformation. Interestingly, all the recovered groups did not return back to their normal state. It can be concluded that both herbicides are endocrine disrupters and cause cellular toxicity indicated by the decrease of protein content and the increase in CYP4501B1-like immunoreactivity. This toxicity is irreversible and the snail is not able to recover its normal state. The fluctuation of CYP4501B1 suggests that this vertebrate-like enzyme may be functional also in the snail and may be used as a biomarker for insecticide toxicity. PMID:24215068

  11. 中国近海刍秣螺亚科的研究(腹足纲,骨螺科)%Study on species of Ocenbrinae from the China coasts(Gastro-poda: Muricidae)

    Institute of Scientific and Technical Information of China (English)

    张素萍

    2009-01-01

    This paper deals with species of the Ocenebrinae(Gastropoda: Muricidae)collected from China coast waters, which occur the Bohai, Yellow Sea and East China Sea, and live in the low-tidal level or in shallow water or deeper, living on rocks or sandy gravel bottom. Subfamily Ocenebrinae was studied on population quantity, distribution and ecological habitat using traditional morphological taxonomic methods based on the mollusca collections of Institute of Oceanology, the Chinese Academy of Sciences. Of the 9 i-dentified species belonging to 4 genera, 1 species was recorded for the first time in China(with asterisk*)%为了摸清中国沿海分布的刍秣螺亚科(Ocenebrinae)的物种数量,以及分布状况和生活习性,完成刍秣螺亚科的系统分类研究.采用传统的形态分类学方法,对中国科学院海洋研究所历年来在中国沿海采集的刍秫螺亚科标本进行了整理分类,共鉴定出刍秣螺亚科4属,9种,其中1种在中国沿海为首次报道.文中对刍秣螺亚科动物的形态特征、习性及地理分布等进行了较详细的描述.

  12. Two interconnected kernels of reciprocally inhibitory interneurons underlie alternating left-right swim motor pattern generation in the mollusk Melibe leonina.

    Science.gov (United States)

    Sakurai, Akira; Gunaratne, Charuni A; Katz, Paul S

    2014-09-15

    The central pattern generator (CPG) underlying the rhythmic swimming behavior of the nudibranch Melibe leonina (Mollusca, Gastropoda, Heterobranchia) has been described as a simple half-center oscillator consisting of two reciprocally inhibitory pairs of interneurons called swim interneuron 1 (Si1) and swim interneuron 2 (Si2). In this study, we identified two additional pairs of interneurons that are part of the swim CPG: swim interneuron 3 (Si3) and swim interneuron 4 (Si4). The somata of Si3 and Si4 were both located in the pedal ganglion, near that of Si2, and both had axons that projected through the pedal commissure to the contralateral pedal ganglion. These neurons fulfilled the criteria for inclusion as members of the swim CPG: 1) they fired at a fixed phase in relation to Si1 and Si2, 2) brief changes in their activity reset the motor pattern, 3) prolonged changes in their activity altered the periodicity of the motor pattern, 4) they had monosynaptic connections with each other and with Si1 and Si2, and 5) their synaptic actions helped explain the phasing of the motor pattern. The results of this study show that the motor pattern has more complex internal dynamics than a simple left/right alternation of firing; the CPG circuit appears to be composed of two kernels of reciprocally inhibitory neurons, one consisting of Si1, Si2, and the contralateral Si4 and the other consisting of Si3. These two kernels interact with each other to produce a stable rhythmic motor pattern.

  13. Benthic macroinvertebrates in Italian rice fields

    Directory of Open Access Journals (Sweden)

    Daniela Lupi

    2013-02-01

    Full Text Available Rice fields can be considered man-managed temporary wetlands. Five rice fields handled with different management strategies, their adjacent channels, and a spring were analysed by their benthic macroinvertebrate community to i evaluate the role of rice agroe- cosystem in biodiversity conservation; ii find indicator species which can be used to compare the ecological status of natural wetlands with rice agroecosystems; and iii find the influence of environmental variables on biodiversity. Different methods of data analysis with increasing degree of complexity – from diversity index up to sophisticated multivariate analysis – were used. The investigation provided a picture of benthic macroinvertebrates inhabiting rice agroecosystems where 173 taxa were identified, 89 of which detected in rice paddies. Among them, 4 phyla (Mollusca, Annelida, Nematomorpha, and Arthropoda, 8 classes (Bivalvia, Gastropoda, Oligochaeta, Hirudinea, Gordioida, Insecta, Branchiopoda, and Malacostraca, 24 orders, 68 families, 127 genera and 159 species have been found. Ten threatened and 3 invasive species were detected in the habitats examined. The information obtained by the different methods of data analysis allowed a more comprehensive view on the value of the components of rice agroecosystems. Data analyses highlighted significant differences between habitats (feeding channel and rice field, with higher diversity observed in channels, and emphasised the role of the water chemical-physical parameters. The period of water permanence in rice fields resulted to be only one of the factors influencing the community of benthic macroinvertebrates. The presence of rare/endangered species allowed characterising some stations, but it was less informative about management strategies in rice paddies because most of these species were absent in rice fields.

  14. Deep mRNA sequencing of the Tritonia diomedea brain transcriptome provides access to gene homologues for neuronal excitability, synaptic transmission and peptidergic signalling.

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    Adriano Senatore

    Full Text Available The sea slug Tritonia diomedea (Mollusca, Gastropoda, Nudibranchia, has a simple and highly accessible nervous system, making it useful for studying neuronal and synaptic mechanisms underlying behavior. Although many important contributions have been made using Tritonia, until now, a lack of genetic information has impeded exploration at the molecular level.We performed Illumina sequencing of central nervous system mRNAs from Tritonia, generating 133.1 million 100 base pair, paired-end reads. De novo reconstruction of the RNA-Seq data yielded a total of 185,546 contigs, which partitioned into 123,154 non-redundant gene clusters (unigenes. BLAST comparison with RefSeq and Swiss-Prot protein databases, as well as mRNA data from other invertebrates (gastropod molluscs: Aplysia californica, Lymnaea stagnalis and Biomphalaria glabrata; cnidarian: Nematostella vectensis revealed that up to 76,292 unigenes in the Tritonia transcriptome have putative homologues in other databases, 18,246 of which are below a more stringent E-value cut-off of 1x10-6. In silico prediction of secreted proteins from the Tritonia transcriptome shotgun assembly (TSA produced a database of 579 unique sequences of secreted proteins, which also exhibited markedly higher expression levels compared to other genes in the TSA.Our efforts greatly expand the availability of gene sequences available for Tritonia diomedea. We were able to extract full length protein sequences for most queried genes, including those involved in electrical excitability, synaptic vesicle release and neurotransmission, thus confirming that the transcriptome will serve as a useful tool for probing the molecular correlates of behavior in this species. We also generated a neurosecretome database that will serve as a useful tool for probing peptidergic signalling systems in the Tritonia brain.

  15. The early radiation of stem group molluscs against the environmental background

    Science.gov (United States)

    Gubanov, A. P.

    2003-04-01

    The first helcionelloid molluscs appeared in the late Nemakit-Daldynian and were forerunners of the sudden molluscan diversification of the Cambrian explosion. The diversification of Mollusca is coincided with global changes in lithosphere, hydrosphere, atmosphere, and biosphere coincident with the rearrangement of the Late Proterozoic supercontinent Rodinia, a distinct shift in oceanic water geochemistry, and a sudden abundance of shelled multicellular organisms. Some of these changes have left indicators in the morphology and chemical properties of molluscan shells that allow reconstruction of global settings which are essential for understanding early molluscan evolution. A combination of tectonic and climatic cyclic changes is resulted in a major global transgression at the beginning of the Cambrian and the formation of extensive shallow water habitats within which the first molluscs expanded. Diversification into new ecological niches has been recognised in two evolutionary-adaptive lineages. The lineage from Oelandiella to Watsonella shows adaptation to a soft substrate and infaunal mode of life. In contrast, the Oelandiella-Helcionella lineage was an adaptation to a harder substrate. Appearance of large helcionelloids with associated archaeocyathan reefs in the middle Tommotian may suggest evolution of a browsing carnivorous habit capable of supporting a considerably larger body. Despite of a few such examples, most helcionelloids remained a small size until the Early Ordovician. Early Cambrian helcionelloids show considerable morphological diversity providing a fertile ground for speculation about early molluscan evolution. While almost the all molluscan classes are known from the Cambro-Ordovician transition, the relationship of these, including Tergomya, Gastropoda, Cephalopoda, and Rostroconchia to helcionelloids remains highly problematic. Analysis of morphological variation and evolutionary trends within the earliest molluscs may support derivation of

  16. Distribution, feeding behavior and control strategies of the exotic land snail Achatina fulica (Gastropoda: Pulmonata) in the northeast of Brazil Ecologia do caracol exótico Achatina fulica (Gastropoda:Pulmonata) no nordeste do Brasil

    OpenAIRE

    FS. Albuquerque; MC. Peso-Aguiar; MJT. Assunção-Albuquerque

    2008-01-01

    The goal of this study was to document the distribution and establishment A. fulica such as their feeding preference and behavior in situ. The study was carried out at the city of Lauro de Freitas, Bahia state, Brazil, between November 2001 and November 2002. We used catch per unit effort methods to determine abundance, distribution, habitat choice and food preferences. The abundance and distribution of A. fulica was most representative in urban area, mainly near to the coastline. Lots and ho...

  17. Estudo quantitativo de metais presentes na hemolinfa de Biomphalaria glabrata (Gastropoda, infectadas e não infectadas com Schistosoma mansoni Quantitative study of metal present in the hemolymph of Biomphalaria glabrata (Gastropoda, infected and uninfected with Schistosoma mansoni

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    Marco Antonio Vasconcelos Santos

    2005-04-01

    Full Text Available Inicialmente, desenvolveu-se um estudo para quantificar e comparar as concentrações de alguns metais presentes em duas amostras de hemolinfa do caramujo Biomphalaria glabrata (infectados e não-infectados com Schistosoma mansoni. A espectrometria de emissão óptica com fonte de plasma induzido (ICP-OES, foi utilizada para analisar os metais nas duas amostras. Os metais estudados foram: alumínio, cálcio, cádmio, cobalto, cromo, cobre, ferro, potássio, magnésio, manganês, chumbo e zinco. Os resultados mostram que, a princípio, os metais não são fatores determinantes no processo de defesa desses organismos contra este parasita, quando presente nos seus tecidos.We conducted a preliminary study to quantify and compare two concentrations of the same metals present in the hemolymph of snail Biomphalaria glabrata. In this context, we used Induction Coupled Plasma Optical Emission Spectroscopy technique (ICP-OES, to analyze the metals in the two samples (snails infected and not infected with Schistosoma mansoni. The metals studied were: aluminum, calcium, cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, lead and zinc. Preliminary results showed that such metals are not involved in the defense of these organisms against the parasite, when present in their tissues.

  18. Desenvolvimento de Eurytrema coelomaticum (Giard & Billet (Digenea, Dicrocoeliidae em Bradybaena similaris (Férussac (Gastropoda, Xanthonychidae Development of Eurytrema coelomaticum (Giard & Billet (Digenea, Dicrocoeliidae in Bradybaena similaris (Férussac (Gastropoda, Xanthonychidae

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    Solange Viana Paschoal Blanco Brandolini

    2001-06-01

    Full Text Available To follow the larval developmenl of Eurytrema coelomaticum (Giard & Billet, 1892 in Bradybaena similaris (Férussac, 1821 snails were separated in three classes using the shell diameter: Class A (14.5-10.2 mm, Class B (10.1-6.9 mm and Class C (6.8-2.6 mm. Only snails belonging to classes A and B acquired the infection. Specimens of E. coelomaticum removed from the pancreatic ducts were exposed to three physiological solutions: Earle, Locke and saline 0.85%, to obtain eggs for the experimental infections, The Locke solution induced the best egg release. The route of migration the intramolluscan development of E. coelomaticum was studied with the aid of histology. The minimal period of intramolluscan developmenl, ending at the expelling of daughter sporocysts, was 107 days for the snails infected in March, and 79 days for the snails infected in November. The Student "t" test and the Chi-square test showed a significant difference (α = 5% between the two periods, although the mean temperature registered during the experiments did not significantly differed (α = 5%. The elimination of daughter sporocysts occurred through the snail's pneumostome, and always at night. Most sporocysts were eliminated at intervals that varied between one to three days, without regularity. The time of elimination of the daughter sporocysts was different for the two infection period studied: 12 weeks for the snails infected in March, and three weeks for those infected in November. Positive correlation between the number of sporocysts expelled by the snail host and higher temperatures registered in the laboratory was observed. This correlation was more evident in November infection.

  19. Conducta de forrajeo del gastrópodo Acanthina monodon Pallas, 1774 (Gastropoda: Muricidae en el intermareal rocoso de Chile central Foraging behavior of the gastropod Acanthina monodon Pallas, 1774 (Gastropoda: Muricidae in the intertidal rocky shores of central Chile

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    RUBÉN E. SOTO

    2004-03-01

    Full Text Available En el presente trabajo investigamos aspectos de la ecología y conducta de forrajeo de Acanthina monodon, un gastrópodo murícido que habita en el intermareal rocoso de Chile central. En terreno, estudiamos las variaciones temporales en su distribución, densidad y dieta. En el laboratorio, cuantificamos la tasa de consumo, las preferencias alimentarias, el tiempo de ingestión y la rentabilidad energética obtenida con distintos tipos de presas mediante experimentos y registros en video. Las mayores densidades de individuos de A. monodon fueron observadas en la franja intermareal cercana al nivel cero de marea. En terreno, A. monodon realiza sus actividades de forrajeo principalmente durante la noche y su dieta consistió principalmente de mitílidos (95 % y cirripedios (5 %. La composición de la dieta de A. monodon en terreno presentó variaciones temporales las cuales dependerían principalmente de cambios en la oferta de los distintos tipos de mitílidos presentes en terreno durante los dos años de muestreo. En el laboratorio, los individuos de Acanthina presentaron preferencias alimentarias significativas por el mitílido Semimytilus algosus. En general, A. monodon bajo condiciones de laboratorio presentó una conducta de forrajeo en la cual maximizó la ganancia neta de energía, mediante la selección de las especies y tamaños de presas que le retribuyen la mayor rentabilidad energéticaWe investigated the ecology and foraging behavior of Acanthina monodon, a muricid gastropod that inhabits in the intertidal rocky shores of central Chile. In the field, we studied temporal variation of their spatial distribution, density, and diet composition. While in the laboratory, we quantified the consumption rate, alimentary preferences, ingestion times and energy profitability obtained with different types of prey using experiments and video recording. High densities of A. monodon individuals were observed in the intertidal fringe near at the level tide zero. In the field, A. monodon actively foraged at night preying mainly on mussels (95 % and barnacles (5 %. Temporal variation in diet composition of A. monodon was caused mostly by changes in the cover of different mussel species during the two years of sampling. In the laboratory, individual of A. monodon showed significant preference for the mussel Semimytilus algosus. In these experiments, A. monodon's foraging behavior maximized the net gain of energy by selecting species and sizes of prey that provided the greatest energy profitability

  20. Parámetros reproductivos y poblacionales de Thais chocolata (Duelos, 1832 (Gastropoda, Thaididae, en la reserva marina La Rinconada, Antofagasta, Chile Reproductive and population parameters of Thais chocolata (Duclos, 1832 (Gastropoda, Thaididae in La Rinconada marine reserve, Antofagasta, Chile

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    Marcela Cantillánez

    2011-11-01

    Full Text Available Para obtener antecedentes reproductivos y poblacionales de Thais chocolata que contribuyan a validar su actual normativa pesquera, se realizó un estudio en el área protegida de la reserva marina La Rinconada, Antofagasta, Chile, entre diciembre 2008 y enero 2010. Los resultados obtenidos indicaron a nivel reproductivo, que el desarrollo gonadal de la población es asincrónico, encontrándose ejemplares en diferentes etapas de maduración durante el año. Los individuos maduros se estratificaron entre 5 y 13 m de profundidad, y gran parte del año formaron agregaciones a 5 m de profundidad. Se determinaron períodos de mayor madurez en julio-agosto, y en noviembre-enero, manifestándose las agregaciones más importantes al final de ellos. Una relación se observó entre meses de mayor madurez y registro de agregaciones, con aquellos de mayor variación intradiaria de temperatura. A nivel poblacional los resultados permitieron estimar una población de 2,3*10(6 ejemplares, donde el 39% se encontró sobre la talla mínima legal (TML = 55 mm. Los parámetros de crecimiento mostraron crecimiento relativamente lento, que podría estar influenciado por la alta variabilidad que presenta la temperatura de fondo en este sector. Mientras que su talla crítica, y la talla de primera madurez sexual poblacional, resultaron ser mayores a la TML. Se determinó la necesidad de revisar la normativa pesquera actual de esta especie, y se demostró la efectividad de las reservas marinas propiciadas por el Estado en la conservación de los recursos marinos.Reproductive and population parameters of Thais chocolata that would contribute to the validation of the current extraction standards were obtained by performing a study in the protected area of La Rinconada Marine Reserve, Antofagasta, Chile, from December 2008 to January 2010. In terms of reproduction, the results revealed asynchronic gonad development in the population, with specimens in different stages of maturity throughout the year. Mature individuals were distributed between 5 and 13 m depth, forming aggregations at 5 m depth during much of the year. Periods of greater maturity were observed from July to August and November to January, with the most important aggregations at the end of both periods. A relationship was observed between the months with the greatest maturity and aggregations and the months with the highest daily temperature fluctuations. At the population level, the results allowed us to estimate 2.3*10(6 individuals, with 39% of this population over the minimum legal size (55 mm. The relatively slow growth estimated for this population was probably influenced by the high variability of the bottom temperature in this area. The critical size and size at first maturity of the population were higher than the minimal legal size, making it is necessary to review the current fishing regulation for this species. The effectiveness of the State marine reserves in the conservation of this marine resource was demonstrated.

  1. The effects of temperature and oxygen availability on intracapsular development of Acanthina monodon (Gastropoda: Muricidae El efecto de la temperatura y la disponibilidad de oxígeno sobre el desarrollo intracapsular de Acanthina monodon (Gastropoda: Muricidae

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    MIRIAM FERNÁNDEZ

    2006-06-01

    Full Text Available Freshwater and marine organisms show similar models of parental care and are faced with similar constraints to brood, which suggest that comparable environmental limits drive the evolution of parental care in aquatic systems. In fact, the low diffusion coefficient and solubility of oxygen in aquatic environments affect oxygen acquisition and therefore the capacity to aggregate embryos. The effect of other critical environmental variables, such as temperature, is less clear. We assessed the effects of temperature and oxygen availability on (1 the number of developed and undeveloped encapsulated embryos, (2 the proportion of embryos reaching advanced stages during intracapsular development (counting not only developed and undeveloped embryos but also abnormal embryos, (3 asynchrony in development (estimated only in capsules in which development occurred, and (4 final embryo size, as the first step toward identifying the main factors constraining parental care in the ocean. We used the gastropod Acanthina monodon as a model because it has an extended latitudinal range of distribution and exhibits feeding larvae during intracapsular development. The latter factor is relevant because previous studies have suggested that sibling cannibalism could be triggered by intracapsular competition for oxygen. Freshly laid egg capsules were collected and incubated until embryos hatched under different experimental temperatures (7, 11, 15 and 19 °C and oxygen conditions (hypoxia: 50-60 % air saturation; normoxia; and hyperoxia: 150-160 %. More embryos remained in early stages at the end of the experimental period under hypoxia and at the highest experimental temperature. The mean number of developed embryos was significantly lower under hypoxia conditions than under normoxia and hyperoxia, but was not influenced by temperature. However, temperature negatively affected embryo size of developed embryos and the level of asynchrony (number of different developmental stages per capsule. This suggests that even when a comparable number of embryos develops at high temperature, subsequent survival may be affected, since developed embryos attained smaller sizes. The negative effect of high temperature on embryo aggregation has also been reported for Brachyuran crabs, affecting female patterns of oxygen provision and brooding costs. This evidence suggests that aggregating embryos in the ocean, even under optimum oxygen conditions, may be negatively affected at high temperatures. Spatial patterns of distribution of brooding species in the ocean tend to agree with this prediction. Our analysis is particularly relevant given the current increase in temperature and the proportion of anoxic areas in the world's oceansLos organismos marinos y dulceacuícolas muestran modelos similares de cuidado parental y están confrontados con similares restricciones para incubar, lo que sugiere que existen límites ambientales comparables guiando la evolución del cuidado parental en sistemas acuáticos. El bajo coeficiente de difusión y la baja solubilidad del oxígeno en ambientes acuáticos afecta la adquisición de oxígeno y por lo tanto la capacidad para agregar los embriones. El efecto de otras variables ambientales críticas, como la temperatura, es menos claro. Se evaluaron los efectos de la temperatura y la disponibilidad de oxígeno sobre (1 el número de embriones desarrollados y sin desarrollar, (2 la proporción de embriones que alcanza estados avanzados de desarrollo (contabilizando no solo embriones desarrollados y sin desarrollar sino también anormales, (3 la asincronía en el desarrollo (estimada solo cuando ocurrió desarrollo embrionario, y (4 el tamaño final, con el objetivo final de identificar las limitaciones que estos factores imponen sobre el cuidado parental en el mar. La especie modelo fue el gastrópodo Acanthina monodon. Cápsulas recientemente depositadas fueron colectadas e incubadas bajo diferentes condiciones experimentales de temperatura (7, 11, 15 y 19 °C y oxígeno (hipoxia: 50-60 % saturación de aire; normoxia; e hiperoxia: 150-160 %. Más embriones permanecieron en fases tempranas del desarrollo al final del experimento en hipoxia y a 19 °C. El número promedio de embriones desarrollados fue significativamente más bajo en hipoxia que bajo normoxia e hiperoxia, pero no fue influenciado por la temperatura. Sin embargo, la temperatura de incubación afectó otras variables de respuesta. Menores tamaños de los embriones y mayores niveles de asincronía al final del desarrollo fueron observados en las más altas temperaturas experimentales, lo que podría tener consecuencias negativas sobre la sobrevivencia posasentamiento. Las altas temperaturas también afectan el comportamiento y los costos asociados a la provisión de oxígeno a los embriones en braquiuros. Estas evidencias sugieren que agregar embriones en el océano, aun en condiciones óptimas de oxígeno, podría ser desfavorable a altas temperaturas. Los patrones espaciales de distribución de especies incubadoras tienden a apoyar esta predicción. Nuestro análisis también cobra relevancia en el escenario actual de aumento de la temperatura media de los océanos y de la proporción de zonas anóxicas

  2. Fluctuating helical asymmetry and morphology of snails (Gastropoda in divergent microhabitats at 'Evolution Canyons I and II,' Israel.

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    Shmuel Raz

    Full Text Available BACKGROUND: Developmental instability of shelled gastropods is measured as deviations from a perfect equiangular (logarithmic spiral. We studied six species of gastropods at 'Evolution Canyons I and II' in Carmel and the Galilee Mountains, Israel, respectively. The xeric, south-facing, 'African' slopes and the mesic, north-facing, 'European' slopes have dramatically different microclimates and plant communities. Moreover, 'Evolution Canyon II' receives more rainfall than 'Evolution Canyon I.' METHODOLOGY/PRINCIPAL FINDINGS: We examined fluctuating asymmetry, rate of whorl expansion, shell height, and number of rotations of the body suture in six species of terrestrial snails from the two 'Evolution Canyons.' The xeric 'African' slope should be more stressful to land snails than the 'European' slope, and 'Evolution Canyon I' should be more stressful than 'Evolution Canyon II.' Only Eopolita protensa jebusitica showed marginally significant differences in fluctuating helical asymmetry between the two slopes. Contrary to expectations, asymmetry was marginally greater on the 'European' slope. Shells of Levantina spiriplana caesareana at 'Evolution Canyon I,' were smaller and more asymmetric than those at 'Evolution Canyon II.' Moreover, shell height and number of rotations of the suture were greater on the north-facing slopes of both canyons. CONCLUSIONS/SIGNIFICANCE: Our data is consistent with a trade-off between drought resistance and thermoregulation in snails; Levantina was significantly smaller on the 'African' slope, for increasing surface area and thermoregulation, while Eopolita was larger on the 'African' slope, for reducing water evaporation. In addition, 'Evolution Canyon I' was more stressful than Evolution Canyon II' for Levantina.

  3. Developmental toxicity of metaldehyde in the embryos of Lymnaea stagnalis (Gastropoda: Pulmonata) co-exposed to the synergist piperonyl butoxide.

    Science.gov (United States)

    Hallett, Katrina C; Atfield, Andrew; Comber, Sean; Hutchinson, Thomas H

    2016-02-01

    Metaldehyde is a widely used molluscicide in countries where damage to crops from slugs and snails is a major problem associated with warm and wet winters. In the UK it is estimated that over 8% of the area covered by arable crops is treated with formulated granular bait pellets containing metaldehyde as the main active ingredient. Metaldehyde is hydrophilic (log Kow=0.12), water soluble (200 mg·L(-1) at 17 °C) and has been detected in UK surface waters in the concentration range of typically 0.2-0.6 μg·L(-1) (maximum 2.7 μg·L(-1)) during 2008-2011. In the absence of chronic data on potential hazards to non-target freshwater molluscs, a laboratory study was conducted to investigate the impact of metaldehyde on embryo development in the gastropod Lymnaea stagnalis (RENILYS strain) and using zinc as a positive control. L. stagnalis embryos were exposed to metaldehyde under semi-static conditions at 20±1 °C and hatching success and growth (measured as shell height and intraocular distance) examined after 21 d. Exposure concentrations were verified using HPLC and gave 21 d (hatching)NOEC and (hatching)LOEC mean measured values of 36 and 116 mg MET·L(-1), respectively (equal to the 21 d (shell height)NOEC and (shell height)LOEC values). For basic research purposes, a second group of L. stagnalis embryos was co-exposed to metaldehyde and the pesticide synergist piperonyl butoxide (PBO). Co-exposure to the PBO (measured concentrations between 0.47-0.56 mg·L(-1)) reduced hatching success from 100% to 47% and resulted in a 30% reduction in embryo growth (shell height) in snail embryos co-exposed to metaldehyde at 34-36 mg·L(-1) over 21 d. In conclusion, these data suggest mollusc embryos may have some metabolic detoxication capacity for metaldehyde and further work is warranted to explore this aspect in order to support the recent initiative to include molluscs in the OECD test guideline programme. PMID:26575636

  4. Hoenselaaria, a new genus with the description of a new species (Gastropoda: Eulimidae) from the Indo-Pacific

    OpenAIRE

    Moolenbeek, R.G.

    2009-01-01

    The type species of the genus Microstilifer, Stilifer auricula Hedley, 1907 is a rather common, but minute, Indo-Pacific micromollusc that needs a new generic and specific name due to misinterpretation of its identity. The genus Hoenselaaria new genus is introduced with its type species Hoenselaaria wareni new species. This species occurs nearly all over the tropical Indo-Pacific but it has been overlooked until now probably due to its extremely small size.

  5. Hoenselaaria, a new genus with the description of a new species (Gastropoda: Eulimidae) from the Indo-Pacific

    NARCIS (Netherlands)

    R.G. Moolenbeek

    2009-01-01

    The type species of the genus Microstilifer, Stilifer auricula Hedley, 1907 is a rather common, but minute, Indo-Pacific micromollusc that needs a new generic and specific name due to misinterpretation of its identity. The genus Hoenselaaria new genus is introduced with its type species Hoenselaaria

  6. Effects of parasitism and environment on shell size of the South American intertidal mud snail Heleobia australis (Gastropoda)

    Science.gov (United States)

    Alda, Pilar; Bonel, Nicolás; Cazzaniga, Néstor J.; Martorelli, Sergio R.

    2010-04-01

    The aim of this work was to evaluate the effects of parasitism and certain environmental factors on the shell size of Heleobia australis (Hydrobiidae, Cochliopinae). We report sporocysts and metacercariae of Microphallus simillimus (Microphallidae, Trematoda) parasitizing the gonad and digestive gland of H. australis specimens from two sites of Bahía Blanca estuary, Argentina. The prevalence of infection was significantly higher (34.17% in winter and 68.14% in late spring) in snails from the outer estuary at Site 2 than in those from the inner estuary at Site 1 (5.88% and 4.71% respectively). The only known definitive host for this digenean is the white-backed stilt Himantopus melanurus (Recurvirostridae, Aves), most abundant in the estuary during winter. Parasitism by M. simillimus causes variations in the shell dimensions of H. australis, the shells of infected snails being narrower than those of uninfected snails. Snails from Site 2 were found in general to be significantly smaller than those at Site 1, possibly as a result of differences in environmental factors such as the degree of exposure to wave energy, the allocation of energy to reproduction rather than growth (induced by predation and/or parasitic castrators) and anthropogenic stressors.

  7. Philinidae, Laonidae and Philinorbidae (Gastropoda: Cephalaspidea: Philinoidea) from the northeastern Pacific Ocean and the Beaufort Sea (Arctic Ocean).

    Science.gov (United States)

    Valdés, Ángel; Cadien, Donald B; Gosliner, Terrence M

    2016-01-01

    Based on morphological data a total of nine native species of Philinidae are recognized from the northeastern Pacific including the Bering Sea and the adjacent Arctic Ocean (Beaufort Sea). Four of them have been previously described: Philine ornatissima Yokoyama, 1927, Philine bakeri Dall, 1919, Philine polystrigma (Dall, 1908), and Philine hemphilli Dall, 1919. Five of them are new and described herein: Philine mcleani sp. nov., Philine baxteri sp. nov., Philine malaquiasi sp. nov., Philine wareni sp. nov., and Philine harrisae sp. nov. These species display a substantial degree of variation in internal and external morphological traits (i.e., presence/absence of gizzard plates, different radular structure and tooth morphology, various reproductive anatomical features) and it is likely that they belong to different clades (genera). However, in the absence of a comprehensive phylogeny for Philine, they are here provisionally regarded as Philine sensu lato. In addition to the nine native species, two introduced species: Philine orientalis A. Adams, 1854 and Philine auriformis Suter, 1909 are here illustrated and compared to the native species to facilitate identification. Finally, two species previously considered members of Philinidae are examined anatomically and confirmed as members of Laonidae, Laona californica (Willett, 1944) and Philinorbidae, Philinorbis albus (Mattox, 1958), based on morphological data. PMID:27515632

  8. Revision of Partulidae (Gastropoda, Stylommatophora) of Palau, with description of a new genus for an unusual ground-dwelling species

    Science.gov (United States)

    Slapcinsky, John; Kraus, Fred

    2016-01-01

    Abstract We describe a new stylommatophoran land snail of the family Partulidae from Palau. The new species has a combination of morphological and ecological characters that do not allow its placement in any existing partulid genus, so we describe a new genus for it. The new genus is characterized by a large (18–23 mm) obese-pupoid shell; smooth protoconch; teleoconch with weak and inconsistent, progressively stronger, striae; last half of body whorl not extending beyond the penultimate whorl; widely expanded and reflexed peristome; relatively long penis, with longitudinal pilasters that fuse apically into a fleshy ridge that divides the main chamber from a small apical chamber; and vas deferens entering and penial-retractor muscle attaching at the apex of the penis. Unlike all other partulids, the new species is strictly associated with rocks in contact with the ground. Comparing the other three Palauan species – currently assigned to Partula – to our new genus and to other partulids makes it clear that they require their own genus because their morphology is quite different from that of true Partula and from that of all other genera. Hence, we resurrect the name Palaopartula Pilsbry for these snails. PMID:27667931

  9. The ibero-balearic region: one of the areas of highest Hydrobiidae (Gastropoda, Prosobranchia, Rissooidea diversity in Europe

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    Arconada, Beatriz

    2003-12-01

    Full Text Available The prosobranch mollusc family Hydrobiidae Troschel, 1857 has a cosmopolitan distribution and is made up of small to minute species that inhabit permanent aquatic ecosystems. It is one of the largest families within the superfamily Rissooidea. The evolutionary relationships between members of this family are still unclear due to: 1 insufficient available information regarding the morphological characters of many of the described taxa, 2 uncertainty concerning which morphological characters are of greatest taxonomic and phylogenetic interest, and 3 the rare use of molecular characters to study evolutionary relationships. In this work, we examine the reasons for the confusing systematics of hydrobiids. We include a diagnosis of the 13 genera and a list of the 43 species described and accepted to date for the Ibero-balearic region, along with data regarding their geographic distribution and a compilation of the most relevant bibliographical references. The Iberian Peninsula is one of the areas of greatest hydrobiid diversity in Europe, and has a large number of endemic genera and species in addition to those that have a typically circummediterranean distribution. Numerous hydrobiid species and populations are threatened, and in some cases, in danger of extinction due to the fragile nature of many of the ecosystems they inhabit.

    La familia Hydrobiidae Troschel, 1857 de moluscos prosobranquios, tiene distribución cosmopolita y está constituida por especies de tamaño pequeño (o incluso diminuto que habitan ecosistemas acuáticos permanentes. Se trata de una de las familias con mayor número de especies de la superfamilia Rissooidea. Las relaciones evolutivas entre los miembros de esta familia son aún confusas debido a: (1 la insuficiente información disponible sobre los caracteres morfológicos de muchos de los táxones descritos, (2 la indefinición de los caracteres morfológicos de interés taxonómico y filogenético, y (3 la escasa aplicación de los caracteres moleculares para este fin. En este trabajo se revisa la confusa sistemática de los hidróbidos y sus causas. Además, se incluye una diagnosis de los 13 géneros y un listado de las 43 especies hasta ahora descritas y aceptadas en el ámbito ibero-balear, con datos sobre su distribución geográfica y la bibliografía más relevante. Se constata que la Península Ibérica constituye una de las áreas de mayor diversidad de hidróbidos en Europa, conteniendo un alto número de géneros y especies endémicos a los que se añaden otros de distribución circunmediterránea. La fragilidad de muchos de los ecosistemas en los que viven hace que muchas de sus especies y/o poblaciones se hallen amenazadas e incluso en peligro de extinción.

  10. Developmental toxicity of metaldehyde in the embryos of Lymnaea stagnalis (Gastropoda: Pulmonata) co-exposed to the synergist piperonyl butoxide.

    Science.gov (United States)

    Hallett, Katrina C; Atfield, Andrew; Comber, Sean; Hutchinson, Thomas H

    2016-02-01

    Metaldehyde is a widely used molluscicide in countries where damage to crops from slugs and snails is a major problem associated with warm and wet winters. In the UK it is estimated that over 8% of the area covered by arable crops is treated with formulated granular bait pellets containing metaldehyde as the main active ingredient. Metaldehyde is hydrophilic (log Kow=0.12), water soluble (200 mg·L(-1) at 17 °C) and has been detected in UK surface waters in the concentration range of typically 0.2-0.6 μg·L(-1) (maximum 2.7 μg·L(-1)) during 2008-2011. In the absence of chronic data on potential hazards to non-target freshwater molluscs, a laboratory study was conducted to investigate the impact of metaldehyde on embryo development in the gastropod Lymnaea stagnalis (RENILYS strain) and using zinc as a positive control. L. stagnalis embryos were exposed to metaldehyde under semi-static conditions at 20±1 °C and hatching success and growth (measured as shell height and intraocular distance) examined after 21 d. Exposure concentrations were verified using HPLC and gave 21 d (hatching)NOEC and (hatching)LOEC mean measured values of 36 and 116 mg MET·L(-1), respectively (equal to the 21 d (shell height)NOEC and (shell height)LOEC values). For basic research purposes, a second group of L. stagnalis embryos was co-exposed to metaldehyde and the pesticide synergist piperonyl butoxide (PBO). Co-exposure to the PBO (measured concentrations between 0.47-0.56 mg·L(-1)) reduced hatching success from 100% to 47% and resulted in a 30% reduction in embryo growth (shell height) in snail embryos co-exposed to metaldehyde at 34-36 mg·L(-1) over 21 d. In conclusion, these data suggest mollusc embryos may have some metabolic detoxication capacity for metaldehyde and further work is warranted to explore this aspect in order to support the recent initiative to include molluscs in the OECD test guideline programme.

  11. Philinidae, Laonidae and Philinorbidae (Gastropoda: Cephalaspidea: Philinoidea) from the northeastern Pacific Ocean and the Beaufort Sea (Arctic Ocean).

    Science.gov (United States)

    Valdés, Ángel; Cadien, Donald B; Gosliner, Terrence M

    2016-08-08

    Based on morphological data a total of nine native species of Philinidae are recognized from the northeastern Pacific including the Bering Sea and the adjacent Arctic Ocean (Beaufort Sea). Four of them have been previously described: Philine ornatissima Yokoyama, 1927, Philine bakeri Dall, 1919, Philine polystrigma (Dall, 1908), and Philine hemphilli Dall, 1919. Five of them are new and described herein: Philine mcleani sp. nov., Philine baxteri sp. nov., Philine malaquiasi sp. nov., Philine wareni sp. nov., and Philine harrisae sp. nov. These species display a substantial degree of variation in internal and external morphological traits (i.e., presence/absence of gizzard plates, different radular structure and tooth morphology, various reproductive anatomical features) and it is likely that they belong to different clades (genera). However, in the absence of a comprehensive phylogeny for Philine, they are here provisionally regarded as Philine sensu lato. In addition to the nine native species, two introduced species: Philine orientalis A. Adams, 1854 and Philine auriformis Suter, 1909 are here illustrated and compared to the native species to facilitate identification. Finally, two species previously considered members of Philinidae are examined anatomically and confirmed as members of Laonidae, Laona californica (Willett, 1944) and Philinorbidae, Philinorbis albus (Mattox, 1958), based on morphological data.

  12. Hemocyte-specific responses to the peroxidizing herbicide fomesafen in the pond snail Lymnaea stagnalis (Gastropoda, Pulmonata)

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Jacqueline [UMR 6553 Ecobio CNRS Universite de Rennes 1, Campus de Beaulieu, F-35042 Rennes cedex 35042 (France); Lefeuvre-Orfila, Luz [UMR 985 INRA-Agrocampus Ecobiologie et Qualite des Hydrosystemes Continentaux, Equipe Ecotoxicologie et Qualite des Milieux aquatiques, 65 rue de Saint-Brieuc CS 84215, F-35042 Rennes cedex 35042 (France); Lagadic, Laurent [UMR 985 INRA-Agrocampus Ecobiologie et Qualite des Hydrosystemes Continentaux, Equipe Ecotoxicologie et Qualite des Milieux aquatiques, 65 rue de Saint-Brieuc CS 84215, F-35042 Rennes cedex 35042 (France)]. E-mail: laurent.lagadic@rennes.inra.fr

    2007-03-15

    Responses of circulating hemocytes were studied in Lymnaea stagnalis exposed to 10, 30, 90, and 270 {mu}g/L fomesafen for 24 and 504 h. Flow cytometry was used to quantify fomesafen-induced production of reactive oxygen species (ROS), phagocytic activity on Escherichia coli, and oxidative burst when hemocytes were challenged by E. coli or phorbol 12-myristate-13-acetate (PMA). Lysosomal membrane damage was assessed, using the neutral-red retention time (NRRT) assay. Exposure to fomesafen for 24 h resulted in increase in ROS levels and decreases in phagocytosis and the oxidative burst in PMA-stimulated hemocytes. After 504 h, intracellular levels of ROS returned to normal, but phagocytosis of E. coli was still inhibited and the associated oxidative burst significantly reduced. After both durations of exposure, decreases of NRRT indicated that lysosome membrane fragility increased with fomesafen concentration. Potential implications for the health and survival of the snails and consequences on populations are discussed. - Fomesafen inhibited phagocytosis and the associated oxidative burst, and increased lysosome fragility in L. stagnalis hemocytes.

  13. Observations on Neotricula aperta (Gastropoda: Pomatiopsidae population densities in Thailand and central Laos: implications for the spread of Mekong schistosomiasis

    Directory of Open Access Journals (Sweden)

    Attwood Stephen W

    2012-06-01

    Full Text Available Abstract Background The snail Neotricula aperta transmits Mekong schistosomiasis in southern Laos and Cambodia, with about 1.5 million people at risk of infection. Plans are under consideration for at least 12 hydroelectric power dams on the lower Mekong river and much controversy surrounds predictions of their environmental impacts. Unfortunately, there are almost no ecological data (such as long term population trend studies available for N. aperta which could be used in impact assessment. Predictions currently assume that the impacts will be the same as those observed in Africa (i.e., a worsening of the schistosomiasis problem; however, marked ecological differences between the snails involved suggest that region specific models are required. The present study was performed as an initial step in providing data, which could be useful in the planning of water resource development in the Mekong. Snail population density records were analyzed for populations close to, and far downstream of, the Nam Theun 2 (NT2 project in Laos in order to detect any changes that might be attributable to impoundment. Results The population immediately downstream of NT2 and that sampled 400 km downstream in Thailand both showed a long term trend of slow growth from 1992 to 2005; however, both populations showed a marked decline in density between 2005 and 2011. The decline in Thailand was to a value significantly lower than that predicted by a linear mixed model for the data, whilst the population density close to NT2 fell to undetectable levels in 2011 from densities of over 5000 m-2 in 2005. The NT2 dam began operation in 2010. Conclusions The impact of the NT2 dam on N. aperta population density could be more complex than first thought and may reflect the strict ecological requirements of this snail. There was no indication that responses of N. aperta populations to dam construction are similar to those observed with Bulinus and Schistosoma haematobium in Africa, for example. In view of the present findings, more ecological data (in particular population density monitoring and surveillance for new habitats are urgently required in order to understand properly the likely impacts of water resource development on Mekong schistosomiasis.

  14. The complete mitochondrial genome of Haliotis laevigata (Gastropoda: Haliotidae) using MiSeq and HiSeq sequencing.

    Science.gov (United States)

    Robinson, Nick A; Hall, Nathan E; Ross, Elizabeth M; Cooke, Ira R; Shiel, Brett P; Robinson, Andrew J; Strugnell, Jan M

    2016-01-01

    The mitochondrial genome of greenlip abalone, Haliotis laevigata, is reported. MiSeq and HiSeq sequencing of one individual was assembled to yield a single 16,545 bp contig. The sequence shares 92% identity to the H. rubra mitochondrial genome (a closely related species that hybridize with H. laevigata in the wild). The sequence will be useful for determining the maternal contribution to hybrid populations, for investigating population structure and stock-enhancement effectiveness.

  15. Subgeneric division of the genus Orcula Held 1837 with remarks on Romanian orculid data (Gastropoda, Pulmonata, Orculidae

    Directory of Open Access Journals (Sweden)

    Barna Pall-Gergely

    2013-05-01

    Full Text Available The genital anatomy of Orcula jetschini (Romania, O. zilchi (Bulgaria and O. wagneri (Albania is described. Based on anatomical features (morphology of the penial caecum, shell characters (sculpture and shape and unpublished molecular data, the genus Orcula is subdivided into three subgenera. O. zilchi was classified within the monotypic subgenus Orcula (Hausdorfia subgen. n.; O. jetschini, O. wagneri and O. schmidtii were classified to Orcula (Illyriobanatica subgen. n. (type species: Pupa Schmidtii, whereas the other Orcula species remain in the nominotypical subgenus. Orcula (Hausdorfia is known from South-Eastern Bulgaria and North-Western Turkey, Orcula (Illyriobanatica inhabits Western Romania, North-Western Greece, Albania, Macedonia, Kosovo and Montenegro. The nine species of Orcula (Orcula are known mainly from the Alps and the Western Carpathians (from Eastern France to Eastern Hungary and Slovakia.The occurrence of only one Orcula species, namely O. jetschini is verified from Romania. Available information suggests that data on the Romanian occurrence of Orcula dolium and O. gularis were based on wrongly identified specimens. Sphyradium dobrogicum (=Orcula dobrogica is considered as a synonym of S. doliolum.

  16. Surviving the Messinian Salinity Crisis? Divergence patterns in the genus Dendropoma (Gastropoda: Vermetidae) in the Mediterranean Sea.

    Science.gov (United States)

    Calvo, Marta; Alda, Fernando; Oliverio, Marco; Templado, José; Machordom, Annie

    2015-10-01

    Four genetically distinct clades were recently described under the name Dendropoma petraeum, a Mediterranean endemic vermetid gastropod. The aim of this work is to date the processes that drove to the diversification within this taxon and to relate them to the corresponding historical events occurred in the Mediterranean Sea. Sequences from mitochondrial and nuclear markers were obtained from specimens collected in 29 localities spanning over 4000km across the entire distribution range of D. petraeum species complex. The phylogenetic and coalescent-based analyses confirmed the four well-supported and largely differentiated lineages of D. petraeum, clearly delimited geographically along a west-east axis within the Mediterranean Sea: Western, Tyrrhenian-Sicilian, Ionian-Aegean and Levantine lineages. Divergence time estimates, obtained using a range of known substitution rates for other marine gastropods, indicated two main stages of diversification. In the first period (between 9.5 and 4.5mya), the ancestral D. petraeum diverged into the current four lineages. The most recent period occurred between 3.72 and 0.66mya in the late Pliocene-early Pleistocene, and included the main within-lineage diversification events. Therefore, if the divergence time between the major lineages of Dendropoma in the Mediterranean actually predated or coincided with the Messinian Salinity Crisis, then they should have survived to this dramatic period within the Mediterranean, as supported by Bayes Factors model comparison. Conversely, if the divergence started after the crisis, congruent with the idea that no true marine organism survived the Messinian Salinity Crisis, then our results indicate substitution rates of Dendropoma much higher than usual (5.16% per million years for COI, 3.04% for 16S). More recent climate changes seem to have conditioned the demographic history of each lineage differently. While Western and Tyrrhenian-Sicilian lineages both underwent an increase in their effective population sizes from 1.5 to 0.6mya coinciding with a long interglacial period, the Ionian-Aegean and Levantine lineages showed constant effective population sizes since 2-2.5mya, suggesting that these eastern lineages might represent small and relict populations surviving the subsequent Quaternary glaciations in isolated refugia. PMID:26002830

  17. Cryptic species in tropic sands--interactive 3D anatomy, molecular phylogeny and evolution of meiofaunal Pseudunelidae (Gastropoda, Acochlidia.

    Directory of Open Access Journals (Sweden)

    Timea P Neusser

    Full Text Available BACKGROUND: Towards realistic estimations of the diversity of marine animals, tiny meiofaunal species usually are underrepresented. Since the biological species concept is hardly applicable on exotic and elusive animals, it is even more important to apply a morphospecies concept on the best level of information possible, using accurate and efficient methodology such as 3D modelling from histological sections. Molecular approaches such as sequence analyses may reveal further, cryptic species. This is the first case study on meiofaunal gastropods to test diversity estimations from traditional taxonomy against results from modern microanatomical methodology and molecular systematics. RESULTS: The examined meiofaunal Pseudunela specimens from several Indo-Pacific islands cannot be distinguished by external features. Their 3D microanatomy shows differences in the organ systems and allows for taxonomic separation in some cases. Additional molecular analyses based on partial mitochondrial cytochrome c oxidase subunit I (COI and 16S rRNA markers revealed considerable genetic structure that is largely congruent with anatomical or geographical patterns. Two new species (Pseudunela viatoris and P. marteli spp. nov. are formally described integrating morphological and genetic analyses. Phylogenetic analysis using partial 16S rRNA, COI and the nuclear 18S rRNA markers shows a clade of Pseudunelidae species as the sister group to limnic Acochlidiidae. Within Pseudunela, two subtypes of complex excretory systems occur. A complex kidney already evolved in the ancestor of Hedylopsacea. Several habitat shifts occurred during hedylopsacean evolution. CONCLUSIONS: Cryptic species occur in tropical meiofaunal Pseudunela gastropods, and likely in other meiofaunal groups with poor dispersal abilities, boosting current diversity estimations. Only a combined 3D microanatomical and molecular approach revealed actual species diversity within Pseudunela reliably. Such integrative methods are recommended for all taxonomic approaches and biodiversity surveys on soft-bodied and small-sized invertebrates. With increasing taxon sampling and details studied, the evolution of acochlidian panpulmonates is even more complex than expected.

  18. A new member of troglobitic Carychiidae, Koreozospeum nodongense gen. et sp. n. (Gastropoda, Eupulmonata, Ellobioidea is described from Korea

    Directory of Open Access Journals (Sweden)

    Adrienne Jochum

    2015-08-01

    Full Text Available A new genus of troglobitic Carychiidae Jeffreys, 1830 is designated from Nodong Cave, North Chungcheong Province, Danyang, South Korea. This remarkable find represents a great range extension and thus, a highly distant distribution of troglobitic Carychiidae in Asia. The Zospeum-like, carychiid snails were recently included, without a formal description, in records documenting Korean malacofauna. The present paper describes Koreozospeum Jochum & Prozorova, gen. n. and illustrates the type species, K. nodongense Lee, Prozorova & Jochum, sp. n. using novel Nano-CT images, including a video, internal shell morphology, SEM and SEM-EDX elemental compositional analysis of the shell.

  19. Bulinus globosus (Planorbidae; Gastropoda) populations in the Lake Victoria basin and coastal Kenya show extreme nuclear genetic differentiation

    DEFF Research Database (Denmark)

    Nyakaana, Silvester; Stothard, J. Russell; Nalugwa, Allen;

    2013-01-01

    and quantified using FST statistics and Bayesian clustering algorithms. The four loci used in this study contained sufficient statistical power to detect low levels of population genetic differentiation and were highly polymorphic with the number of alleles per locus across populations ranging from 16 to 22...

  20. [Genetic diversity in two populations of the snail Strombus gigas (Gastropoda: Strombidae) from Yucatan, Mexico, using microsatellite].

    Science.gov (United States)

    Zamora-Bustillos, Roberto; Rodríguez-Canul, Rossanna; García de León, Francisco J; Tello Cetina, Jorge

    2011-09-01

    The pink conch Strombus gigas is an important fisheries resource in the Caribbean region, including the Yucatán Peninsula. We analyzed the genetic diversity and genetic structure of two populations (Alacranes Reef and Chinchorro Bank) with the use of five microsatellite molecular markers. The results indicate that the two populations are in the same rank of genetic diversity (He), from 0.613 to 0.692. Significant deviation from H-WE was observed in the both populations due to deficit to heterozygotes, this was attributed to inbreeding as a consequence of over-fishing; nevertheless, other possible causes considered are mixing of individuals from two or more populations, and the existence of null alleles. Levels of genetic differentiation indicated the existence of a single homogenous population in the Yucatan Peninsula (F(ST) de 0.003, p = 0.49), which fits with highest levels of gene flow is significant (2.3 individuals) between both populations. Results from this study support the hypothesis that S. gigas is part of a single panmictic population in the Yucatan Peninsula; therefore, this fishery resource should be regulated the same way for both areas. PMID:22017119

  1. Description and evaluation of imposex in Strombus canarium Linnaeus, 1758 (Gastropoda, Strombidae): a potential bio-indicator of tributyltin pollution.

    Science.gov (United States)

    Cob, Zaidi Che; Arshad, Aziz; Bujang, Japar Sidik; Abd Ghaffar, Mazlan

    2011-07-01

    Strombus canarium Linnaeus, 1758 is an important gastropod species within the study area and was traditionally collected for food by the locals. The objective of the present study is to assess the incidence of imposex and its severity in this species. Adult conchs were sampled during their main reproductive period, from October 2005 to January 2006, at Sungai Pulai estuary, Johor Straits, Malaysia. A total of 32.81% of adult females showed imposex characteristics, with varying degrees of severity though. The relative penis size (RPS) index ranged from 1.74 to 33.29 (mean = 13.40 ± 2.27, n = 21), while the relative penis length (RPL) index ranged from 6.28 to 55.19 (mean = 25.83 ± 3.33, n = 21). The use of vas deferens sequence (VDS) index was however cannot be applied as the presence of egg groove obscured any vas deferens development in affected females. Sequence of imposex (male penis) development in female conch, from merely a small stump to an advance male penis homologous was therefore carefully analyzed and described, and an alternative imposex classification scheme was proposed. S. canarium can be a good indicator for monitoring of organotin pollution within the study area. However, more studies are needed in order to further develop and test its validity and application, such as its correlation with levels of pollutant within the tissues and the environment, as well as its application on other Strombus species. PMID:20824325

  2. Impacts of Urbanization on the Biodiversity of the Imperiled Snail Fauna (Gastropoda: Prosobranchia: Pleuroceridae) of the Cahaba River, Alabama, USA.

    Science.gov (United States)

    Tolley-Jordan, L.; Huryn, A.

    2005-05-01

    The conservation of the Pleuroceridae is of concern in the Mobile River Basin (MRB) since 31 of 38 extinct gastropod species from this drainage are pleurocerids. The fauna of the Cahaba River, as a global hot-spot for pleurocerid diversity, is of particular concern. Its flow is not regulated by dams, so its fauna has not been affected by habitat alteration due to impoundment like other major MRB tributaries. Ongoing urbanization within its watershed, however, is expected to have consequences for its snail fauna. A 1993 survey documented 23 pleurocerid species among 109 sites in the drainage. Changes in land cover from 1992 to 2004 were quantified for 10 of these. Five sites showed a 13-36% increase in urban land-cover; five showed no change. Elimia cahawbensis, E. carinifera, E. carinocostata, E. clara and Pleurocera vestita occurred among these sites during 1993 (S= 0-4 spp./site). A comparison of species occurrence in 1992 and 2005 showed no change in S at 6 sites, while three lost 1 species, and one lost 3 species. Reductions in S were not correlated with changes in land cover, however. Factors not directly correlated with urbanization may thus be contributing to losses of snail diversity in the MRB.

  3. Sibynomorphus neuwiedi (Ihering, 1911 (Serpentes; Dipsadidae and Potamojanuarius lamellatus (Semper, 1885 (Gastropoda; Veronicellidae: a trophic relationship revealed

    Directory of Open Access Journals (Sweden)

    Thiago Maia-Carneiro

    2012-03-01

    Full Text Available The Dispsadidae serpents from the genus Sibynomorphus are restricted to South America and include twelve species currently known, which occur in Brazil, Argentina, Peru, and Ecuador. Sibynomorphus neuwiedi is a species endemic to forested areas of the Atlantic Rainforest biome, and it is specialized in eating gastropods. Eight adult individuals of S. neuwiedi were collected between April 1998 and June 2003 at the surroundings of the Vila dos Dois Rios village (23°11’S, 44°12’W, in the Parque Estadual da Ilha Grande, in the municipality of Angra dos Reis, state of Rio de Janeiro, Brazil. In the laboratory, we dissected their stomachs for analysis of its contents. We found prey in four of them (50%, all represented by the slug Potamojanuarius lamellatus (Veronicellidae, and four individuals had empty stomach. The consumption of slugs from the Family Veronicellidae by serpents from the tribe Dipsadini has been reported, nevertheless, we report the occurrence of P. lamellatus in the diet of S. neuwiedi for the first time.

  4. Host and ecology both play a role in shaping distribution of digenean parasites of New Zealand whelks (Gastropoda: Buccinidae: Cominella).

    Science.gov (United States)

    Donald, Kirsten M; Spencer, Hamish G

    2016-08-01

    Digenean parasites infecting four Cominella whelk species (C. glandiformis, C. adspersa, C. maculosa and C. virgata), which inhabit New Zealand's intertidal zone, were analysed using molecular techniques. Mitochondrial 16S and cytochrome oxidase 1 (COI) and nuclear rDNA ITS1 sequences were used to infer phylogenetic relationships amongst digenea. Host species were parasitized by a diverse range of digenea (Platyhelminthes, Trematoda), representing seven families: Echinostomatidae, Opecoelidae, Microphallidae, Strigeidae and three, as yet, undetermined families A, B and C. Each parasite family infected between one and three host whelk species, and infection levels were typically low (average infection rates ranged from 1·4 to 3·6%). Host specificity ranged from highly species-specific amongst the echinostomes, which were only ever observed infecting C. glandiformis, to the more generalist opecoelids and strigeids, which were capable of infecting three out of four of the Cominella species analysed. Digeneans displayed a highly variable geographic range; for example, echinostomes had a large geographic range stretching the length of New Zealand, from Northland to Otago, whereas Family B parasites were restricted to fairly small areas of the North Island. Our results add to a growing body of research identifying wide ranges in both host specificity and geographic range amongst intertidal, multi-host parasite systems. PMID:27278710

  5. Identification of two carbonic anhydrases in the mantle of the European Abalone Haliotis tuberculata (Gastropoda, Haliotidae): phylogenetic implications.

    Science.gov (United States)

    LE Roy, Nathalie; Marie, Benjamin; Gaume, Béatrice; Guichard, Nathalie; Delgado, Sidney; Zanella-Cléon, Isabelle; Becchi, Michel; Auzoux-Bordenave, Stéphanie; Sire, Jean-Yves; Marin, Frédéric

    2012-07-01

    Carbonic anhydrases (CAs) represent a diversified family of metalloenzymes that reversibly catalyze the hydration of carbon dioxide. They are involved in a wide range of functions, among which is the formation of CaCO(3) skeletons in metazoans. In the shell-forming mantle tissues of mollusks, the location of the CA catalytic activity is elusive and gives birth to contradicting views. In the present paper, using the European abalone Haliotis tuberculata, a key model gastropod in biomineralization studies, we identified and characterized two CAs (htCA1 and htCA2) that are specific of the shell-forming mantle tissue. We analyzed them in a phylogenetic context. Combining various approaches, including proteomics, activity tests, and in silico analyses, we showed that htCA1 is secreted but is not incorporated in the organic matrix of the abalone shell and that htCA2 is transmembrane. Together with previous studies dealing with molluskan CAs, our findings suggest two possible modes of action for shell mineralization: the first mode applies to, for example, the bivalves Unio pictorum and Pinctada fucata, and involves a true CA activity in their shell matrix; the second mode corresponds to, for example, the European abalone, and does not include CA activity in the shell matrix. Our work provides new insight on the diversity of the extracellular macromolecular tools used for shell biomineralization study in mollusks.

  6. A new species of Haplosporidium Caullery & Mesnil, 1899 in the marine false limpet Siphonaria lessonii (Gastropoda: Siphonariidae) from Patagonia.

    Science.gov (United States)

    Ituarte, Cristián; Bagnato, Estefanía; Siddall, Mark; Cremonte, Florencia

    2014-05-01

    A new species of Haplosporidium Caullery & Mesnil, 1899 parasitising the pulmonate gastropod Siphonaria lessonii Blainville in Patagonia, Argentina, is described based on morphological (scanning and transmission electron microscopy) and sequence (small subunit ribosomal RNA gene) data. Different stages of sporulation were observed as infections disseminated in the digestive gland. Haplosporidium patagon n. sp. is characterised by oval or slightly subquadrate spores with an operculum that is ornamented with numerous short digitiform projections of regular height, perpendicular to and covering its outer surface. The operculum diameter is slightly larger than the apical diameter of the spore. Neither the immature nor mature spores showed any kind of projections of the exosporoplasm or of the spore wall. Regarding phylogenetic affinities, the new species was recovered as sister to an undescribed species of Haplosporidium Caullery & Mesnil, 1899 from the polychaete family Syllidae Grube from Japanese waters. The morphological characters (ornamentation of the operculum, spore wall structure, shape and size of spores, and the lack of spore wall projections) corroborate it as an as yet undescribed species of Haplosporidium and the first for the phylum in marine gastropods of South America. Siphonaria lessonii is the only known host to date.

  7. Aberrant Forms of the Genus Clio Linnaeus, 1767, with a Review of the Genus Proclio Hubendick, 1951 (Gastropoda, Pteropoda)

    NARCIS (Netherlands)

    Spoel, S.v.d.

    1962-01-01

    The examination of two aberrant Pteropods collected during a trip with the whale factory-ship ”m.s. Willem Barendsz” led to the conclusion that they were animals in a resting stage. The histology and the anatomy of the totally aberrant soft parts was discussed. The shells of the specimens indicate t

  8. Antimicrobial activities of the tissue extracts of Babylonia spirata Linnaeus, 1758 (Mollusca:Gastropoda) from Thazhanguda, southeast coast of India

    Institute of Scientific and Technical Information of China (English)

    Periyasamy N; Srinivasan M; Balakrishnan S

    2012-01-01

    Objective: To investigate the antimicrobial activity of the tissue extracts of Babylonia spirata (B. spirata) against nine bacterial and three fungal pathogens. Methods: Crude extract of gastropod was tested for inhibition of bacterial and fungal growth. Antibacterial assay was carried out by disc diffusion method and in vitro antifungal activity was determined against Czapex Dox agar. The antimicrobial activity was measured accordingly based on the inhibition zone around the disc impregnated with gastropod extract. Molecular size of muscle protein was determined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). And fourier transform infrared spectroscopy (FTIR) spectro photometry analysis was also studied. Results:The maximum inhibition zone (12 mm) was observed against Pseudomonas aeruginosa in the crude ethanol extract of B. spirata and the minimum inhibition zone (2 mm) was noticed againstStaphylococcus aureus in the crude methanol extract of B. spirata. Water extract of B. spirata showed the highest activity against Vibrio parahaemolyticus, Staphylococcus aureus and Candidaalbicans. Ethanol, acetone, methanol, chloroform and water extracts showed antimicrobial activity against almost all the bacteria and fungus. Compared with water extracts, ethanol and methanol extracts showed higher activity against all pathogens. The molecular weight of protein of the gastropod sample ranged from 2-110 kDa on SDS-PAGE. FTIR analysis revealed the presence of bioactive compounds signals at different ranges. Conclusions: The research shows that the great medicinal value of the gastropod muscle of B. spirata may be due to high quality of antimicrobial compounds.

  9. Seasonal bioconcentration of heavy metals in Onchidium struma (Gastropoda: Pulmonata) from Chongming Island, the YangtzeEstuary, China

    Institute of Scientific and Technical Information of China (English)

    LI Xiaobo; JIA Linzhi; ZHAO Yunlong; WANG Qun; CHENG Yongxu

    2009-01-01

    The seasonal concentration changes of selected heavy metal Cd, Cr, Cu, Fe, Mn, Pb, and Zn in five tissues of marine gastropod Onchidium struma were studied in the Chongming Island, the Yangtze Estuary on July 2006, September 2006, and November 2006, April 2007, respectively. The results demonstrated that the bioconcentration factor of Cu (biomass/water) in all selected tissues was about 104 magnitudes, Fe and Cd were 103, Zn was 102, and Mn, Pb, and Cr were 101. Hepatopancreas was proven to be the dominant storage tissue of Cr, Cu, Mn, and Zn, whereas Fe and Pb were mainly stored in muscle and digenetic gland, and Cd was stored in vitelline gland and albumen gland. Additionally, it was found that Cu, Fe, Mn, and Zn were concentrated significantly by O. struma (whole-body) in summer or autumn, and Cd, Cr, and Pb increased slightly in spring and winter. Furthermore, the bioconcentration of Cr was nearly 2-fold higher and Zn was 1.6-fold higher in the water compared with the Water Quality Standard for Fisheries. With view of excessive amount of Pb, Cd, and Cu according to seafood standard, the consumption of O. struma might have the risk of health hazard.

  10. Biosynthesis and composition of sterols and sterol esters in the land snail Cepaea nemoralis (L.) (gastropoda, pulmonata, stylommatophora)

    NARCIS (Netherlands)

    Horst, D.J. van der; Voogt, P.A.

    1972-01-01

    1. 1. The biosynthesis and composition of sterols and sterol esters were studied in the land snail Cepaea nemoralis after injection of Na-1-14C-acetate. 2. 2. Free and esterified sterols appeared to be synthesized by the animals, whilst the specific radioactivity of the sterols from the esters was

  11. Gulella adami, a new species of land snail from the Ivory Coast, West Africa (Gastropoda Pulmonata: Streptaxidae)

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1994-01-01

    Gulella adami spec. nov. is described from a classical West African locality, Assini in the Ivory Coast (Côte d'Ivoire). It is most unusual in showing two superficial parietal processes, which may also be interpreted as a double angular lamella, in the aperture of the shell. The shell closely resemb

  12. Observations on Neotricula aperta (Gastropoda: Pomatiopsidae) population densities in Thailand and central Laos: implications for the spread of Mekong schistosomiasis

    OpenAIRE

    Attwood Stephen W; Upatham E

    2012-01-01

    Abstract Background The snail Neotricula aperta transmits Mekong schistosomiasis in southern Laos and Cambodia, with about 1.5 million people at risk of infection. Plans are under consideration for at least 12 hydroelectric power dams on the lower Mekong river and much controversy surrounds predictions of their environmental impacts. Unfortunately, there are almost no ecological data (such as long term population trend studies) available for N. aperta which could be used in impact assessment....

  13. Influence of joint application of heavy metals on level of each metal accumulated in the periwinkle Tympanotonus fuscatus (Gastropoda: Potamididae)

    International Nuclear Information System (INIS)

    Most laboratory assessments on toxicity and bioaccumulation of heavy metals have been concentrated on the accumulation of these metal ions when exposed singly to the test organisms. However, under the natural environmental settings, the metals are never present in isolation and may interact with each other, therefore justifying the need to study the influence of joint application of metals on accumulated levels in exposed animals. In this study, exposure of the periwinkle Tympanotonus fuscatus to sublethal concentrations (equivalent to 0.1 and 0.01 of 96 h LC50) of heavy metals revealed that they were bioaccumulative varying amounts, depending on the type of metal, exposure period and concentration in the test media. while Zn and Pb ions accumulation increased steadily with exposure time, the amounts of Cu accumulated fluctuated regularly over the 30-day experimental period. The levels of Zn, Cu and Cd bioaccumulated over the 30-day experimental period were reduced by over 2-6 folds (with bioaccumulation radio values ranging from 0.15 to 0.81) when compared to concentrations of the respective metals accumulated during single bioaccumulation studies. However, Pb concentrations accumulated during the joint action studies increased nearly 2-fold (bioaccumulation ratio range 1.36 to 2.0-fold). (author)

  14. Exploring species level taxonomy and species delimitation methods in the facultatively self-fertilizing land snail genus Rumina (gastropoda: pulmonata.

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    Vanya Prévot

    Full Text Available Delimiting species in facultatively selfing taxa is a challenging problem of which the terrestrial pulmonate snail genus Rumina is a good example. These snails have a mixed breeding system and show a high degree of shell and color variation. Three nominal species (R. decollata, R. saharica and R. paivae and two color morphs within R. decollata (dark and light are currently recognized. The present study aims at evaluating to what extent these entities reflect evolutionary diverging taxonomic units, rather than fixed polymorphisms due to sustained selfing. Therefore, a phylogenetic analysis of nuclear (ITS1, ITS2 and mitochondrial DNA (COI, CytB, 12S rDNA, 16S rDNA sequences was performed. Putative species in Rumina, inferred from the mitochondrial DNA phylogeny, were compared with those proposed on the basis of the COI gene by (1 DNA barcoding gap analysis, (2 Automatic Barcode Gap Discovery, (3 the species delimitation plug-in of the Geneious software, (4 the Genealogical Sorting Index, and (5 the General Mixed Yule Coalescent model. It is shown that these methods produce a variety of different species hypotheses and as such one may wonder to what extent species delimitation methods are really useful. With respect to Rumina, the data suggest at least seven species, one corresponding to R. saharica and six that are currently grouped under the name R. decollata. The species-level status of R. paivae is rejected.

  15. Differences in osmotolerance in freshwater and brackish water populations of Theodoxus fluviatilis (Gastropoda: Neritidae) are associated with differential protein expression

    OpenAIRE

    Symanowski, Frauke; Hildebrandt, J.-P.

    2010-01-01

    The euryhaline gastropod Theodoxus fluviatilis is found in northern Germany in freshwater or in brackish water habitats in the Baltic Sea. Previous studies have revealed that individuals from both habitats are not distinguishable by morphological characters or by sequence comparison of DNA encoding 16S RNA or cytochrome C. As reported in this study, animals collected in the two habitats differ substantially in their physiological ability to adapt to different salinities. Comparison of accumul...

  16. Distribution Of The Freshwater Snail Species Fagotia (Gastropoda, Melanopsidae In Ukraine According To Climatic Factors. I. Fagotia Esperi

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    Tytar V.

    2015-08-01

    Full Text Available Maximum entropy niche modeling was employed as a tool to assess potential habitat suitability for the freshwater snail F. esperi (Férussac, 1823 in Ukraine for both contemporary climatic conditions and conditions projected for 2050. Of the 19 bioclimatic predictor variables used in the modeling, the “mean temperature seosonality” “mean temperature of driest quarter” and “precipitation of warmest quarter” were the three most important in predicting habitat suitability and distribution of this mollusk species.

  17. Observations on the breeding habits, shell development, decollation, and reproductive anatomy of Pontophaedusa funiculum (Mousson 1856 (Gastropoda, Pulmonata, Clausiliidae, Phaedusinae

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    Barna Páll-Gergely

    2008-02-01

    Full Text Available The internal and external egg morphology, shell development, decollation process, mating behaviour and reproductive anatomy (genital structure, inner structure of the penis, fine structure of the retractor muscle and the spermatophore of the clausiliid Pontophaedusa funiculum (Mousson 1856 are described, and illustrated by photographs of the laid eggs, their inner structure, juvenile, young adult and old individuals, as well as a schematic drawing of the mating. P. funiculum is the only known clausiliid species with hard shelled eggs and the only known example of the family Clausiliidae which mates face to face. The taxonomic position within the Phaedusinae subfamily is mentioned.

  18. Shell morphometrics in four species of Gadilidae (Mollusca, Scaphopoda in Southwestern Atlantic Ocean, Brazil Morfometria da concha de quatro espécies de Gadilidae (Mollusca, Scaphopoda no Brasil, sudoeste do Oceano Atlântico

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    Ricardo Silva Absalão

    2005-03-01

    Full Text Available Six morphometric shell direct measurements of the Gadilidae species Gadila acus (Dall, 1889, Cadulus braziliensis Henderson, 1920, Cadulus parvus Henderson, 1920 and Polyschides tetraschistus (Watson, 1879 were carried out and used to build three morphometric indices in according to the proposition of SHIMEK (1989: LI, relating total shell length to length from the dorsal aperture to the maximum width; WI, relating maximum shell diameter to apertural diameter; and Ws, whorl expansion rate (sensu RAUP 1966. Direct measurements and morphometric indices were tested as discriminating tools among the four species. None of the morphometric indices, alone, were able to discriminate among all species. Among then, Ws is not an effective discriminating morphometric index because it fails in all pairwise comparisons, LI and WI are fairly efficient ones, since they have got effective discriminations in three out six pairwise comparisons. The combined use of direct measurements ones was more efficient than the indices ones when dealing with relatively small samples, as ours. Although both descriptors can be combiningly used; since the direct measurements descriptors are easier to obtain and understand than the more complex indices, they should be recommended as main tools.Seis medidas morfométricas tomadas diretamente da concha dos seguintes gadilideos: Gadila acus (Dall, 1889, Cadulus braziliensis Henderson, 1920, Cadulus parvus Henderson, 1920 e Polyschides tetraschistus (Watson, 1879 foram realizadas e utilizadas na construção de índices morfométricos em concordância com Shimek (1989: LI, razão entre o comprimento total da concha e o comprimento entre a abertura dorsal até o ponto de máximo diâmetro; WI, razão entre o diâmetro máximo da concha e o diâmetro da abertura; e Ws, taxa de expansão dos anfractos (sensu Raup 1966. Tanto as medidas tomadas diretamente das conchas como os índices morfométricos foram testados como instrumentos de discriminação entre as quatro espécies. Nenhum índice morfométrico, quando considerado isoladamente, foi capaz de discriminar entre todas as espécies. Ws teve o pior desempenho, falhando na discriminação de todas as comparações par-a-par, LI e WI se saíram melhor, desde que discriminaram, corretamente, três das seis comparações par-a-par. A utilização combinada das medidas diretas da concha foi mais eficiente que os índices morfométricos, ao menos ao se tratar de amostras pequenas como as nossas. Embora ambos tipos de descritores possam ser utilizados, a maior simplicidade e facilidade de obtenção das medidas diretas as habilitam como os principais instrumentos de discriminação conquiliológica.

  19. 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

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    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.

  20. 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

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    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.

  1. The interference of methods in the collection of teredinids (Mollusca, Bivalvia in mangrove habitats Interferência de métodos na coleta de teredinídios (Mollusca, Bivalvia em habitats de manguezais

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    Rosa M. V. Leonel

    2006-03-01

    Full Text Available In the estuary of the Mamanguape River (Paraíba, Brazil, a new collection technique was developed and applied with virgin poles of mangrove trees Avicennia schaueriana (Verbenaceae, Rhizophora mangle (Rhizophoraceae, and Laguncularia racemosa (Combretaceae, taking into account wood preference, water salinity and depth influence during teredinid larval settlement. Sets of poles were vertically fixed in the riverbed at three sites along a decreasing salinity gradient, where they stayed for four months. The poles were collected and divided into upper, median, and lower segments, in agreement with different immersion regimes. An increase of 239% was obtained in the number of individuals when compared to a previous study in the same area using a different methodology. The species Teredo bartschi (Clapp, 1923, Nausitora fusticula (Jeffreys, 1860 and Bankia fimbriatula Moll & Roch, 1931 were registered in both studies, and the species Psiloteredo healdi (Bartsch, 1931 is here registered for the first time as occurring in that estuary. The species Neoteredo reynei (Bartsch, 1920, previously registered on tree branches of the mangrove habitat, was not found in the present work. Bankia fimbriatula, the most abundant species, did not show preference for any substratum but occurred significantly on the lower segment of the poles. N. fusticula, second in abundance, preferred to settle on poles of A. schaueriana and on any of the three segments. Aiming to assess the habitat variations, a more accurate study on teredinids diversity in mangrove ecosystems should be performed through a concomitant analysis from tree branches of the mangrove habitat, as well as from poles of mangrove trees or panels made of pine wood or mangrove trees wood. These collection devices should be maintained along a decreasing salinity gradient exposed to different tide levels.Contemplando a preferência pelo tipo de madeira, a influência da profundidade e da salinidade durante assentamento larval de teredinídeos, uma nova técnica de coleta foi aplicada e desenvolvida no estuário do rio Mamanguape (Paraíba, Brasil, utilizando varas virgens de três espécies de árvores do manguezal: Avicennia schaueriana (Verbenaceae, Rhizophora mangle (Rhizophoraceae e Laguncularia racemosa (Combretaceae. Em três estações demarcadas ao longo do gradiente decrescente de salinidade, conjuntos de varas foram verticalmente fixados nas margens do rio. Após quatro meses, as varas eram coletadas e divididas em três segmentos (superior, médio e inferior, de acordo com os regimes de imersão a que foram submetidas. Comparativamente aos dados obtidos por um estudo anterior na mesma área, com outras metodologias de coleta, foi obtido um aumento de 239% no número de indivíduos coletados com a nova técnica. Embora as espécies Teredo bartschi (Clapp, 1923, Nausitora fusticula (Jeffreys, 1860 e Bankia fimbriatula Moll & Roch, 1931 tenham ocorrido nos dois estudos, o teredinídeo Psiloteredo healdi (Bartsch, 1931 tem sua presença registrada pela primeira vez neste estuário. Tendo sido previamente registrada em ramos de árvores do manguezal, Neoteredo reynei (Bartsch, 1920 não foi coletada no presente trabalho. Sendo a espécie mais abundante, B. fimbriatula não mostrou preferência de assentamento em nenhum dos substratos, ocorrendo significativamente associada ao segmento inferior das varas. Como segunda espécie mais abundante, N. fusticula mostrou preferência significativa de assentamento em A. schaueriana, ocorrendo indistintamente nos três segmentos das varas. Visando contemplar as variações do habitat e obter maior precisão de resultados, é recomendável que em estudos sobre a diversidade de teredinídeos, sejam incluídas análises concomitantes de troncos e ramos das árvores, com o uso de varas de árvores do manguezal ou de coletores artificiais feitos com pinho ou madeira de árvores do manguezal. Os coletores devem ser mantidos ao longo do gradiente de salinidade e expostos aos diferentes níveis das marés.

  2. Gloquídio de Diplodon martensi (lhering (Mollusca, Bivalvia, Hyriidae e seu ciclo parasitário The glochidium of Diplodon martensi (lhering (Mollusca, Bivalvia, Hyriidae and its parasitic cycle

    Directory of Open Access Journals (Sweden)

    Maria Cristina Dreher Mansur

    1999-01-01

    Full Text Available Conchological and anatomical studies of the glochidium of Diplodon martensi (lhering, 1893 were performed on samples collected in a small river, tributary from the Caí River, that belong to the Jacuí River sub-basin in south-eastern Brazil. The parasitic development of the glochidium was observed in laboratory on a small cichlid fish Gymnogeophagus gymnogenys (Hensel, 1870.

  3. 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

  4. Development and reproduction in Bulimulus tenuissimus (Mollusca: Bulimulidae in laboratory Padrão de desenvolvimento e aspectos reprodutivos de Bulimulus tenuissimus (Mollusca: Bulimulidae em condições de laboratório

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    Lidiane C. Silva

    2008-06-01

    Full Text Available Bulimulus tenuissimus (d'Orbigny, 1835 is a land snail of parasitological importance with a poorly understood biology. The goal of this laboratory study was to determine development and reproductive patterns in B. tenuissimus. Recently hatched individuals in seven groups of 10 were maintained in the laboratory for two years. To test for self-fertilization, 73 additional individuals were isolated. After 180 days the isolated snails showed no signs of reproduction. Subsequently, 30 of these snails were paired to test fertility. We noted the date and time of egg-laying, the number of eggs produced, the number of egg-layings per individual, the incubation period and hatch success. This species shows indeterminate growth. Individuals that were maintained with others, as compared to isolated individuals, laid eggs sooner, laid more eggs and had a greater hatching success. This species can self-fertilize, however, with lower reproductive success. Bulimulus tenuissimus has a well-defined reproductive period that is apparently characteristic for this species.Apesar de ser uma espécie de importância parasitológica, não existem estudos sobre a biologia de Bulimulus tenuissimus (d'Orbigny, 1835. O objetivo desse trabalho foi verificar o padrão de crescimento e aspectos reprodutivos dessa espécie em laboratório. Assim, 70 animais recém-eclodidos foram distribuídos em sete grupos, com 10 moluscos cada, por um período de dois anos. Para estes animais foi verificado o padrão de crescimento. A ocorrência de autofecundação foi observada através do isolamento de 73 animais. Por não ter sido verificado autofecundação em um período de 180 dias, 30 animais que estavam em isolamento foram pareados de modo a confirmar a fertilidade destes. Registrou-se o tempo para início da oviposição, número de ovos e de posturas, intervalo entre posturas e taxa de eclosão. Foi verificado um padrão de crescimento indeterminado para a espécie. Os animais mantidos agrupados iniciaram a oviposição mais cedo, produziram mais ovos e apresentaram maior eclodibilidade do que os demais grupos. A espécie é capaz de realizar autofecundação, porém um menor sucesso reprodutivo é obtido nesse processo. Os indivíduos de B. tenuissimus apresentaram um período reprodutivo bem definido que parece ser característico para a espécie.

  5. 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.

  6. Filtration and respiration rates of the short-necked clam Paphia undulata (Born, 1778 (Mollusca, Pelecypoda: Veneridae under laboratory conditions

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    Laureen Morillo Manalo

    2010-12-01

    Full Text Available The filtration and respiration rates of various size classes (35-39.99, 40-44.99,45-49.99, 50-54.99 and 55-59.99 mm of the short-necked clam Paphia undulata were measured in the laboratory. The effects of three light regimes (0 lux, 172.22 lux and 645.83 lux, three microalgal species (Isochrysis galbana, Tetraselmis tetrahele and Chaetoceros calcitrans and four microalgal concentrations (10, 25, 50 and 100 x 104 cells ml-1 on filtration rates were investigated. Mean filtration rate was highest (0.57 ± 0.04 Lh-1ind.-1 under total darkness. This can be attributed to the natural environment of this species which is characterized by silty substrate and low visibility. Filtration was also highest in the microalga Isochrysis galbana (0.67 ± 0.05. Rates initially increased from low to moderate microalgal concentrations (25 x 104 cells ml-1 and decreased at higher concentrations. Filtration generally decreased with increase in clam size. Light intensity, microalgal species and microalgal concentration showed significant effects on filtration. Respiration of fed clams was higher (0.138 ± 0.026 ml O2h-1ind.-1 than unfed clams (0.053± 0.025 ml O2h-1 nd.-1 and increased with clam size.

  7. The Early Development of the Short-Necked Clam, Paphia undulata (Born 1778 (Mollusca, Pelecypoda: Veneridae in the Laboratory

    Directory of Open Access Journals (Sweden)

    Annabelle del Norte Campos

    2010-12-01

    Full Text Available The population of Paphia undulata in Negros Occidental waters continues to decline due to unregulated harvesting because of the increasing demand for this resource. One potential effort to mitigate this problem is reseeding or stock enhancement of the natural population. For these efforts to be effective however, successful laboratory rearing and breeding of this species is a prerequisite. Thus, this study was conducted to describe the embryonic and larval development of P. undulata to provide information on laboratory larval rearing. Broodstock were collected during the natural spawning peak from Hinigaran, Negros Occidental and were maintained in a static system with a mean salinity and temperature of 36 ppt. and 26.7 OC, respectively and were fed with Isochrysis galbana, Chaetoceros calcitrans, and Tetraselmis tetrahele. Fertilized eggs started to divide 30 minutes after fertilization. Ciliated swimming blastulas were observed after 1.5 hours with an average shell length (SL of 40 µm. These further developed into trocophore larvae (average SL 60µm after 7 hours and into D-veliger (average SL 80 µm after 12 hours. Fully developed D-larvae (average SL 90 µm were attained after 17 hours. Larvae with completely developed umbo were observed on day 9 with an average SL of 140 µm. On day 13, larvae (average SL 220 µm started to settle and metamorphose. Spontaneous spawning was observed during the peak of reproductive activities of P. undulata showing that collection of broodstock must be conducted during the peak of reproductive season to ensure successful spawning and production of viable gametes under laboratory conditions. Further experiments should be conducted to determine optimum conditions to improve survival rates of the larvae during settlement. The results corroborate other studies and help explain the derived information on the species' population and reproductive biology.

  8. Effects of anthracene on filtration rates, antioxidant defense system, and redox proteomics in the Mediterranean clam Ruditapes decussatus (Mollusca: Bivalvia).

    Science.gov (United States)

    Sellami, Badreddine; Khazri, Abdelhafidh; Louati, Héla; Dellali, Mohamed; Driss, Mouhamed Ridha; Aïssa, Patricia; Mahmoudi, Ezzeddine; Hamouda, Beyrem; Coelho, Ana Varela; Sheehan, David

    2015-07-01

    This study aimed at analyzing the impact of a toxic polyaromatic hydrocarbon (PAH), anthracene (ANT), on Ruditapes decussatus collected from a Tunisian coastal lagoon (Bizerte Lagoon). Filtration rates, several antioxidant enzymes--superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione transferase (GST)--as well as indices of protein oxidation status were determined in various tissues of this bivalve. Specimens were exposed to 100 μg/L of ANT for 2 days. ANT levels were evaluated using HPLC and were detected in the gill and digestive gland at different amounts. ANT exposure altered the behavior of bivalves by changing the siphon movement and decreasing filtration rate significantly. The enzymatic results indicated that ANT exposure affected the oxidative stress status of the gills of R. decussatus. In addition, modification of proteins was detected in the gills using redox proteomics after ANT treatment. Three protein spots were successfully identified by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-MS). These proteins can be roughly related to muscle contraction function. In contrast, no significant modification of enzymatic and protein responses was detected in the digestive gland after ANT treatment. These data demonstrate that combined behavioral and biochemical analyses are a powerful tool to provide valuable insights into possible mechanisms of toxicity of anthracene in R. decussatus. Additionally, the results highlight the potential of the gill as a valuable candidate for investigating PAH toxicity. PMID:25779113

  9. Living on the mountains: patterns and causes of diversification in the springsnail subgenus Pseudamnicola (Corrosella) (Mollusca: Caenogastropoda: Hydrobiidae).

    Science.gov (United States)

    Delicado, Diana; Machordom, Annie; Ramos, Marian A

    2013-09-01

    Hydrobiidae is one of the largest families of freshwater gastropods comprised of approximately 400 genera and 1000 species. Despite this high level of diversity, most hydrobiid species inhabit fragile ecosystems in restricted distribution areas. In this work, we analyze modes of speciation and causes of diversification in the hydrobiid springsnail subgenus Pseudamnicola (Corrosella). Species of this group typically live in nutrient poor springs and streams and are restricted to mountainous regions of the Iberian Peninsula (Spain) and Southern France. Previous morphological and molecular (based only on the cytochrome c oxidase subunit I (COI) gene) studies revealed 11 nominal Corrosella species. In this study, we enhance published molecular results by generating new data from mitochondrial (16S rRNA and COI) and nuclear ribosomal regions (18S and 28S rRNA) from 50 Corrosella populations. As a result of this study we have identified one new species, making a total of twelve recognized species in the subgenus Corrosella. Our phylogenetic results also reveal the existence of three lineages within the subgenus, and the estimation of time divergence indicates the occurrence of three main speciation events during the upper Miocene to Pleistocene. We test the influence of several geographical and ecological variables and observe that diversification patterns are related to habitat fragmentation rather than environmental conditions. This result suggests that the high level of diversity observed within the subgenus may have resulted from a non-adaptive radiation. The formation of the Iberian Peninsula mountain ranges (the Pyrenees in the north and the Betic Cordillera in the south) and the configuration of the Iberian current hydrographic system played important roles in Corrosella speciation. Additionally, during the Miocene the Iberian Peninsula experienced a gradient of increasing temperature and dryness from north to south, which together with a high level of tectonic activity, may have caused the majority of the diversity found in the southern Iberian Peninsula. PMID:23660110

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

    International Nuclear Information System (INIS)

    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

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

    OpenAIRE

    Bruna Aparecida de Souza; Lidiane Cristina da Silva; Evelyn Durço Chicarino; Elisabeth Cristina de Almeida Bessa

    2014-01-01

    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...

  12. The first mitochondrial genome of Coelomactra antiquata (Mollusca: Veneroida: Mactridae) from Guangxi (China) and potential molecular markers.

    Science.gov (United States)

    Shen, Xin; Meng, Xueping; Tian, Mei; Yan, Binlun; Cheng, Hanliang; Lu, Wei; Chai, Yuling

    2016-09-01

    The complete mitochondrial genome of Coelomactra antiquata (Guangxi, in China, GX) was determined. It is 16 801 bp in length and is the first representative from this province. The mitochondrial genome encodes 35 genes, including 12 PCGs, two ribosomal RNA, and 21 transfer RNA genes. Atp8 and trnSer(UCN) genes are missing, compared with the typical gene content of animal mitochondrial genomes. Three (cob, nad1, nad4, and nad6) of the 12 PCGs in the mitochondrial genome initiate with the ATA, while other PCGs start with ATG. Two PCGs (atp6 and nad4L) end with incomplete stop codons (T-), and the remaining ones have complete stop codons (TAA or TAG). The largest non-coding region of the C. antiquata (GX) contains one section of tandem repeats (5 × 99 bp). Among all PCGs and rRNAs, the nad5 gene contains the maximum polymorphic sites (430), followed by nad4 (261) and cox2 (240). Two ribosomal RNA genes (srRNA and lrRNA) and cox1 are most conservative. The proportions of polymorphic sites in six genes (nad4, nad2, nad6, nad5, cox2, and nad3) are more than 20% (ranging from 20.25% to 25.21%). These high variable genes can be used as molecular markers in the population genetic analysis of the species. PMID:26329456

  13. New lucinid bivalves from shallow and deeper water of the Indian and West Pacific Oceans (Mollusca, Bivalvia, Lucinidae

    Directory of Open Access Journals (Sweden)

    John Taylor

    2013-08-01

    Full Text Available Four new species and a new genus of lucinid bivalves are described from shallow and deeper waters in the Indian and West Pacific Oceans. The new genus Scabrilucina (subfamily Lucininae includes the little-known S. victorialis (Melvill, 1899 from the Arabian Sea and S. vitrea (Deshayes, 1844 from the Andaman Sea as well as a new species S. melvilli from the Torres Strait off northeastern Australia. Ferrocina brunei new species (Lucininae was recovered from 60 m near oil drilling activities off Borneo; its anatomy confirmed the presence of symbiotic bacteria. Two unusual deeper water species of Leucosphaerinae are described, both species included in on-going molecular analyses; Gonimyrtea ferruginea from 400–650 m in the southwest Pacific and Myrtina reflexa from 200–825 m off Zanzibar and Madagascar.

  14. Mortality of unionid bivalves (Mollusca) associated with Dreissenid mussels (Dreissena polymorpha and D. bugensis) in Presque Isle Bay, Lake Erie

    Science.gov (United States)

    Schloesser, Don W.; Masteller, Edwin C.

    1999-01-01

    Two exotic species of dreissenid mussels (Dreissena polymorpha and D. bugensis) began to colonize bottom substrates in Presque Isle Bay, Lake Erie in 1990. By 1991, all native unionid (Unionidae) shells were infested by dreissenids. In 1990 and 1991, about 500 individual unionids of 15 species were collected: in 1992, 246 individuals of 12 species were collected; in 1993, 64 individuals of 6 species; in 1994, three individuals of three species; and in 1995, no unionids were found. In general, infestation indices of unionids were relatively low in 1990 and 1991, increased in 1992, and decreased in 1993. Mortality of unionids associated with infestation in the bay occurred in a shorter period of time (ca. two to three years) than has been documented in other water bodies. Observations in an area of Presque Isle not included in the present study, indicate that a small remnant population of unionids exists in the presence of heavily-colonized substrates by dreissenid mussels. Since other shallow-water areas of Lake Erie support infestation-free unionids in the presence of dreissenid mussels, it is hoped that some unionids will survive in Presque Isle Bay of Lake Erie.

  15. 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.

  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. 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. PMID:27129114

  18. 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

  19. Phylogeny of the cuttlefishes (Mollusca:Cephalopoda) based on mitochondrial COI and 16S rRNA gene sequence data

    Institute of Scientific and Technical Information of China (English)

    LIN Xiangzhi; ZHENG Xiaodong; XIAO Shu; WANG Rucai

    2004-01-01

    To clarify cuttlefish phylogeny, mitochondrial cytochrome c oxidase subunit I (COI) gene and partial 16S rRNA gene are sequenced for 13 cephalopod species. Phylogenetic trees are constructed, with the neighbor-joining method.Coleoids are divided into two main lineages, Decabrachia and Octobrachia. The monophyly of the order Sepioidea,which includes the families Sepiidae, Sepiolidae and Idiosepiidae, is not supported. From the two families of Sepioidea examined, the Sepiolidae are polyphyletic and are excluded from the order. On the basis of 16S rRNA and amino acid of COI gene sequences data, the two genera (Sepiella and Sepia) from the Sepiidae can be distinguished, but do not have a visible boundary using COI gene sequences. The reason is explained. This suggests that the 16S rDNA of cephalopods is a precious tool to analyze taxonomic relationships at the genus level, and COI gene is fitter at a higher taxonomic level (i.e., family).

  20. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Helicidae (Mollusca) species as first intermediate hosts of Dicrocoelium dendriticum in the province of León (NW Spain)

    OpenAIRE

    Manga-González, M. Yolanda

    1991-01-01

    Trabajo presentado al: Spring Meeting of the British Society for Parasitology, in conjuntion with the Malacological Society of London and the British Section of the Society of Protozoologists (Liverpool, Gran Bretaña, del 3 al 5 de abril de 1991).

  3. 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.

  4. Free amino acids in the clam Macoma balthica (L.) (Bivalvia, Mollusca) from brackish waters of southern Baltic Sea

    NARCIS (Netherlands)

    Sokolowski, A.; Wolowicz, M.; Hummel, H.

    2003-01-01

    Fourteen acidic and neutral free amino acids (FAA) were investigated in soft tissue of Macoma balthica from different depth zones of the Gulf of Gdansk (Baltic Sea) over a full seasonal cycle. The dry weight of the bivalves and physico-chemical parameters of overlying bottom water and surface sedime

  5. 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.

  6. Phylogenetic analysis of four nuclear protein-encoding genes largely corroborates the traditional classification of Bivalvia (Mollusca).

    Science.gov (United States)

    Sharma, Prashant P; González, Vanessa L; Kawauchi, Gisele Y; Andrade, Sónia C S; Guzmán, Alejandra; Collins, Timothy M; Glover, Emily A; Harper, Elizabeth M; Healy, John M; Mikkelsen, Paula M; Taylor, John D; Bieler, Rüdiger; Giribet, Gonzalo

    2012-10-01

    Revived interest in molluscan phylogeny has resulted in a torrent of molecular sequence data from phylogenetic, mitogenomic, and phylogenomic studies. Despite recent progress, basal relationships of the class Bivalvia remain contentious, owing to conflicting morphological and molecular hypotheses. Marked incongruity of phylogenetic signal in datasets heavily represented by nuclear ribosomal genes versus mitochondrial genes has also impeded consensus on the type of molecular data best suited for investigating bivalve relationships. To arbitrate conflicting phylogenetic hypotheses, we evaluated the utility of four nuclear protein-encoding genes-ATP synthase β, elongation factor-1α, myosin heavy chain type II, and RNA polymerase II-for resolving the basal relationships of Bivalvia. We sampled all five major lineages of bivalves (Archiheterodonta, Euheterodonta [including Anomalodesmata], Palaeoheterodonta, Protobranchia, and Pteriomorphia) and inferred relationships using maximum likelihood and Bayesian approaches. To investigate the robustness of the phylogenetic signal embedded in the data, we implemented additional datasets wherein length variability and/or third codon positions were eliminated. Results obtained include (a) the clade (Nuculanida+Opponobranchia), i.e., the traditionally defined Protobranchia; (b) the monophyly of Pteriomorphia; (c) the clade (Archiheterodonta+Palaeoheterodonta); (d) the monophyly of the traditionally defined Euheterodonta (including Anomalodesmata); and (e) the monophyly of Heteroconchia, i.e., (Palaeoheterodonta+Archiheterodonta+Euheterodonta). The stability of the basal tree topology to dataset manipulation is indicative of signal robustness in these four genes. The inferred tree topology corresponds closely to those obtained by datasets dominated by nuclear ribosomal genes (18S rRNA and 28S rRNA), controverting recent taxonomic actions based solely upon mitochondrial gene phylogenies.

  7. A preliminary study for establishing Perna viridis (Mollusca:Bivalvia) as a biological monitor for pollution in Karachi coastal water

    OpenAIRE

    Zehra, Itrat; Naz, Huma; Naqvi, Iftikhar Imam

    1996-01-01

    Adverse effects of toxic substances on the environmental quality have become a subject of concern in recent years. Toxicity of heavy metals has never been in dispute and therefore their presence in our natural environment is undesirable. This study was undertaken to establish the capability of Perna viridis as a monitor for pollution in the Manora channel. Accumulation of Zinc, Copper, Iron and Manganese by marine mussels, sampled from Manora channel, was determined. Metal load varied markedl...

  8. [On the controversial questions of the taxonomy of Bivalvia (Mollusca): too many species or too few characters?].

    Science.gov (United States)

    Rizhinashvili, A L

    2011-01-01

    Problems emerging in the course of taxonomic studies and species diagnostics of freshwater bivalves are discussed by the example of one of the bivalve groups (the family Unionidae). It is shown that one of the causes of the current, diametrically opposing views on specific and generic systematics of Bivalvia is the fact that researchers revising taxonomic groups ignore complex analysis of several independent characters (conchological, anatomical, biochemical, genetic, etc.).

  9. Mytilus antiquorum J. Sowerby, 1821 and other Pliocene mussels (Mollusca, Bivalvia) from the Southern North Sea Basin

    NARCIS (Netherlands)

    Vervoenen, M.; Wesselingh, F.P.; Nieulande, van F.A.D.

    2000-01-01

    Mytilus antiquorum J. Sowerby, 1821, is recorded from the Coralline Crag Formation of East Anglia (UK) and the Lillo Formation (Oorderen, Kruisschans and Merksem members) of the Antwerp area (Belgium). The species is diagnosed on the basis of newly collected material and differentiated from modern E

  10. Cryptic species of deep-sea clams (Mollusca: Bivalvia: Vesicomyidae) from hydrothermal vent and cold-water seep environments

    Science.gov (United States)

    Vrijenhoek, Robert C.; Schutz, Steven J.; Gustafson, Richard G.; Lutz, Richard A.

    1994-08-01

    A protein-electrophoretic analysis of six putative morphospecies in the bivalve family Vesicomyidae from eight deep-sea hydrothermal vent sites in the eastern Pacific, three cold-water seep sites in the eastern Pacific and the Gulf of Mexico, and one whale-carcass site off Southern California revealed electromorph patterns diagnostic of 10 vesicomyid species. Electrophoretic patterns for 14 enzymes encoded by 17 presumptive gene loci were scored in all 10 species. The pairwise genetic distances (Nei's D) for these 10 species ranged from 0.857 to 2.792, values within the range expected for distinct species and genera. However, the degree of genetic divergence among these taxa could not be used for phylogenetic inferences because allozyme differences had in many cases reached evolutionary saturation. Notwithstanding, the present results revealed a significant problem with current morphospecies identifications of these clams and with applications of the current generic names Calyptogena and Vesicomya. Given the cryptic nature of these taxa, we suggest that subsequent studies simply refer to these clams as "vesicomyids" until careful morphological analyses and molecular studies are completed and systematic relationships are clarified.

  11. Mytilus antiquorum J. Sowerby, 1821 and other Pliocene mussels (Mollusca, Bivalvia) from the Southern North Sea Basin

    OpenAIRE

    Vervoenen, M.; Wesselingh, F.P.; Nieulande, van, F.A.D.

    2000-01-01

    Mytilus antiquorum J. Sowerby, 1821, is recorded from the Coralline Crag Formation of East Anglia (UK) and the Lillo Formation (Oorderen, Kruisschans and Merksem members) of the Antwerp area (Belgium). The species is diagnosed on the basis of newly collected material and differentiated from modern European mussel species. The presence of M. antiquorum in the southern North Sea Basin is restricted to the Middle (Piacenzian) and early Late Pliocene (Gelasian). A possible occurrence of the speci...

  12. First molecular phylogeny of the circumtropical bivalve family Pinnidae (Mollusca, Bivalvia): evidence for high levels of cryptic species diversity.

    Science.gov (United States)

    Lemer, Sarah; Buge, Barbara; Bemis, Amanda; Giribet, Gonzalo

    2014-06-01

    The family Pinnidae Leach, 1819, includes approximately 50 species of large subtidal and coastal marine bivalves. These commercially important species occur in tropical and temperate waters around the world and are most frequently found in seagrass meadows. The taxonomy of the family has been revised a number of times since the early 20th Century, the most recent revision recognizing 55 species distributed in three genera: Pinna, Atrina and Streptopinna, the latter being monotypic. However, to date no phylogenetic analysis of the family has been conducted using morphological or molecular data. The present study analyzed 306 pinnid specimens from around the world, comprising the three described genera and ca. 25 morphospecies. We sequenced the mitochondrial genes 16S rRNA and cytochrome c oxidase subunit I, and the nuclear ribosomal genes 18S rRNA and 28S rRNA. Phylogenetic analysis of the data revealed monophyly of the genus Atrina but also that the genus Streptopinna is nested within Pinna. Based on the strong support for this relationship we propose a new status for Streptopinna Martens, 1880 and treat it as a subgenus (status nov.) of Pinna Linnaeus, 1758. The phylogeny and the species delimitation analyses suggest the presence of cryptic species in many morphospecies displaying a wide Indo-Pacific distribution, including Pinna muricata, Atrina assimilis, A. exusta and P. (Streptopinna) saccata but also in the Atlantic species A. rigida. Altogether our results highlight the challenges associated with morphological identifications in Pinnidae due to the presence of both phenotypic plasticity and morphological stasis and reveal that many pinnid species are not as widely distributed as previously thought.

  13. Multi-locus fossil-calibrated phylogeny, biogeography and a subgeneric revision of the Margaritiferidae (Mollusca: Bivalvia: Unionoida).

    Science.gov (United States)

    Bolotov, Ivan N; Vikhrev, Ilya V; Bespalaya, Yulia V; Gofarov, Mikhail Y; Kondakov, Alexander V; Konopleva, Ekaterina S; Bolotov, Nikita N; Lyubas, Artyom A

    2016-10-01

    The taxonomy and biogeographic history of the bivalve family Margaritiferidae are controversial because previous molecular studies did not provide a well-resolved phylogenetic framework for these enigmatic freshwater mussels that have extensive but disjunct distribution in North America, Eurasia and North Africa. In this study, we present a new, fossil-calibrated phylogenetic hypothesis based on five molecular markers (∼4kb of total length) for ten species. Our results indicate that all recent margaritiferids are in the single genus, Margaritifera Schumacher, 1816. Additionally, we identified three relatively well-supported phylogenetic clades that are valid subgenera, i.e., Margaritifera s. str. (Holarctic), Margaritanopsis (=Cumberlandia) (southeast North America-southeast Asia disjunct) and Pseudunio (Mediterranean). We suggest that the crown lineage of the Margaritiferidae most likely originated in the Cretaceous (mean age 93Ma, 95% CI 66-126Ma). The combined results of ancestral area reconstructions based on the three different approaches (S-DIVA, DEC and S-DEC) showed that ancient vicariance events could have played an important role in speciation within the family. The rates of mitochondrial evolution of margaritiferids are notably slow, which may be associated with their longevity, long generation time and low metabolic rates. Our findings highlight the complex biogeographic history of the Margaritiferidae as an intermixing of ancient vicariance and dispersal events, which were most likely associated with some inland barriers, continental movements and a sea level dynamic.

  14. Where’s Waldo? A new commensal species, Waldo arthuri (Mollusca, Bivalvia, Galeommatidae), from the Northeastern Pacific Ocean

    OpenAIRE

    Paul Valentich-Scott; Diarmaid O'Foighil; Jingchun Li

    2013-01-01

    Abstract A galeommatid bivalve mollusk, representing a new species, is described from off the coasts of California and Vancouver Island, British Columbia. The new bivalve has a commensal relationship with the heart urchin, Brisaster latifrons . It has been observed crawling between the oral spines of this urchin, frequently near the peristome. The bivalve has been recorded from 80 (Vancouver Island) to 444 (southern California) meters depth, in muddy sediments. In common with other galeommato...

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

    Energy Technology Data Exchange (ETDEWEB)

    Blasco, J.; Puppo, J. [Instituto de Ciencias Marinas de Andalucia, Campus Univ. Rio S. Pedro, 11510 Puerto Real, Cadiz (Spain)

    1999-02-01

    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 {mu}g{center_dot}l{sup -1}), Pb (350-700 {mu}g{center_dot}l{sup -1}) and Cu (10-20 {mu}g{center_dot}l{sup -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 {mu}g{center_dot}l{sup -1}, 7 days) and copper (20 {mu}g{center_dot}l{sup -1}, 5 days) were observed significant differences (P<0.05) in foot and gills, respectively, with respect to control. In the case of alanine aminotransferase activity (ALT), significant differences were observed for cadmium and lead in treated animals with respect to control. With regard to copper, a decrease in ALT was observed in gills and foot exposed to 20 {mu}g{center_dot}l{sup -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.)

  16. Bivalvia (Mollusca) of Nansha Islands, China%中国南沙群岛的双壳纲贝类

    Institute of Scientific and Technical Information of China (English)

    蔡英亚; 刘桂茂

    2004-01-01

    报道了中国南沙群岛的双壳纲贝类141种,分隶于5亚纲8目36科77属.从种类的组成中,帘蛤科有18种,蚶科15种,扇贝科11种,鸟蛤科10种,锉蛤科8种,贻贝科、海菊蛤科和樱蛤科各7种,砗磲科6种,其他各科的种类均在5种以内.按种的性质而论,大多数属于和珊瑚礁有密切联系的热带种或亚热带种,区系性质为印度-西太平洋区的印尼-马来亚区.

  17. 栉江珧生殖细胞的发生%Gametogenesis in Atria pectinata Linnaeus (Mollusca, Bivalvia)

    Institute of Scientific and Technical Information of China (English)

    王梅芳; 余祥勇; 王如才

    2000-01-01

    通过观察栉江珧(Atrina pectinata linnaeus)的未分化生殖细胞,精原细胞和卵原细胞,精母细胞和卵母细胞,精子和卵子的形态结构与分布状况及核仁在卵成熟过程中的变化,对栉江珧生殖细胞发生及成熟过程的有关问题进行了探讨.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. The Effects of Mercury Exposure on the Surface Morphology of Gill Filaments in Perna perna (Mollusca: Bivalvia)

    Energy Technology Data Exchange (ETDEWEB)

    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 {mu}g/l{sup -1} over 24 days. Uncontaminated seawater was circulated over the mussels in tank 2 (control) for the same period. A 25 mm{sup 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 {mu}g/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.

  1. Relationship between element concentrations and body size in the Lake Maggiore population of Unio pictorum mancus (Mollusca, Bivalvia

    Directory of Open Access Journals (Sweden)

    Ilenia CATTANI

    2011-08-01

    Full Text Available The study focused on using a fresh-water mussel (Unio pictorum mancus as a bioindicator of various pollutants, and particularly metals. The elements considered were: Al, As, Ca, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V and Zn. This research was carried out at a site where various other studies have been conducted on important characteristics of the same population of Unio. This site is a small bay called "Sabbie d’Oro" located on the south-east coast of Lake Maggiore. Our study involved quantifying the capacity of this mollusc to concentrate large amounts of metal in its body without evident consequences by using detoxification mechanisms. We analysed not only element concentrations, but also their variability (expressed as CV% in the soft tissues and in the shell, for two main reasons: i the sampling design should include a preliminary analysis to determine how many specimens is necessary collect to ensure a specified level of precision; ii the sample variability value may be combined with the value of analytical precision (BCR to obtain an estimate of the "experimental" precision. In soft tissue, Ca accumulation tended to increase with size, and Al accumulation decreased with size. In shell, Ca and Ni were stored more than in soft tissue, but not proportionally to size. V, Cr and Mo tended to accumulate in the shell progressively over the years, whereas Co and Al are "diluted" during growth, or are absorbed mainly during the juvenile stage. Partition between shell and soft tissue resulted roughly the same in the juvenile and adult stages for the following elements: Fe, Al, Co, As, Pb. The relationships among the various elements were schematized in a hierarchical tree plot.

  2. 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.

  3. Plasticity of symbiont acquisition throughout the life cycle of the shallow-water tropical lucinid Codakia orbiculata (Mollusca: Bivalvia).

    Science.gov (United States)

    Gros, Olivier; Elisabeth, Nathalie H; Gustave, Sylvie D D; Caro, Audrey; Dubilier, Nicole

    2012-06-01

    In marine invertebrates that acquire their symbionts from the environment, these are generally only taken up during early developmental stages. In the symbiosis between lucinid clams and their intracellular sulfur-oxidizing bacteria, it has been shown that the juveniles acquire their symbionts from an environmental stock of free-living symbiont forms, but it is not known if adult clams are still competent to take up symbiotic bacteria from the environment. In this study, we investigated symbiont acquisition in adult specimens of the lucinid clam Codakia orbiculata, using transmission electron microscopy, fluorescence in situ hybridization, immunohistochemistry and PCR. We show here that adults that had no detectable symbionts after starvation in aquaria for 6 months, rapidly reacquired symbionts within days after being returned to their natural environments in the field. Control specimens that were starved and then exposed to seawater aquaria with sulfide did not reacquire symbionts. This indicates that the reacquisition of symbionts in the starved clams returned to the field was not caused by high division rates of a small pool of remaining symbionts that we were not able to detect with the methods used here. Immunohistochemistry with an antibody against actin, a protein involved in the phagocytosis of intracellular bacteria, showed that actin was expressed at the apical ends of the gill cells that took up symbionts, providing further evidence that the symbionts were acquired from the environment. Interestingly, actin expression was also observed in symbiont-containing cells of untreated lucinids freshly collected from the environment, indicating that symbiont acquisition from the environment occurs continuously in these clams throughout their lifetime. PMID:22672589

  4. New records and a new species of bivalve (Mollusca: Bivalvia) from Miocene hydrocarbon seep deposits, North Island, New Zealand.

    Science.gov (United States)

    Saether, Kristian P; Jingeng, Sha; Little, Crispin T S; Campbell, Kathleen A

    2016-01-01

    Fourteen bivalve taxa belonging to 11 families are present in at least 13 early to middle Miocene hydrocarbon seep deposits in the East Coast Basin, North Island, New Zealand. Among these are at least three new species, one of which, Semeloidea (s. l.) bexhavenensis sp. nov. (Lasaeidae), is described here. New distribution data are recorded for bivalve species in the families Limidae, Propeamussiidae, Malleidae and Solemyidae. Additional morphological details of Gigantidas coseli (Mytilidae) and Pratulum quinarium (Cardiidae) are provided based upon previously unrecorded internal shell features. Palaeoecological analysis indicates that bivalves utilized a broad range of modes of life and niches within the New Zealand Miocene seep environment, and no more than ca. 30% of these bivalve species were likely to have been obligate to seeps. PMID:27615822

  5. Absence of formation of benzo[a]pyrene/DNA adducts in the cuttlefish (Sepia officinalis, Mollusca: Cephalopoda)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, P.G.; Lu, L.J.W.; Salazar, J.J.; Holoubek, V. (Univ. of Texas Medical Branch, Galveston, TX (United States))

    1994-01-01

    Benzo[a]pyrene (B[a]P) injected intramuscularly into the base of the arms of cuttlefish was released continuously from the injection site and removed from the organism. Only a portion of the compound accumulated in the body. Twenty-four hr after its injection, 75% of B[a]P applied in olive oil was removed from the cuttlefish, and 1.2% was found in the body outside the head, in site of injection. If the carcinogen was dissolved in dimethylformamide, the removal of B[a]P was slower, so that only 18% of the injected B[a]P was removed from the organism and 0.36% accumulated in the body outside the head 24 hr after injection. The high level of B[a]P in gills and hemolymph 4 hr after injection and the kinetics of the decrease of its concentration with time indicate that these two organs could be involved in the excretion of B[a]P from the body. The B[a]P/DNA adducts characteristic for vertebrates could not be demonstrated in gills, skin, brain, hepatopancreas, and lymphocytes of the cuttlefish 24 hr after injection. The dose of the carcinogene injected into the cuttlefish was 2-4 times higher than the dose resulting in the formation of a high level of B[a]P/DNA adducts in vertebrates. A different metabolism of B[a]P in the tissue of cephalopods, compared to vertebrates, could be less favorable to the process leading to malignant transformation and could explain the absence from the literature of reports of tumors in cephalopods. 15 refs., 1 fig., 2 tabs.

  6. A new genus and species of Thyasiridae (Mollusca, Bivalvia from deep-water, Beaufort Sea, northern Alaska

    Directory of Open Access Journals (Sweden)

    Paul Valentich-Scott

    2014-12-01

    Full Text Available Bivalve mollusk shells were collected in 2350 m depth in the Beaufort Sea, Arctic Ocean off northern Alaska. Initial identification suggested the specimens were a member of the bivalve family Thyasiridae, but no known eastern Pacific or Arctic living or fossil thyasirid resembled these deep-water specimens. Comparisons were made with the type of the genera Maorithyas Fleming, 1950, Spinaxinus Oliver & Holmes, 2006, Axinus Sowerby, 1821, and Parathyasira Iredale, 1930. We determined the Beaufort Sea species represents a new genus, herein described as Wallerconcha. These specimens also represent a new species, herein named Wallerconcha sarae. These new taxa are compared with known modern and fossil genera and species of thyasirds.

  7. Biomphalaria straminea (Mollusca: Planorbidae) as an intermediate host of Drepanocephalus spp. (Trematoda: Echinostomatidae) in Brazil: a morphological and molecular study.

    Science.gov (United States)

    Pinto, Hudson A; Griffin, Matt J; Quiniou, Sylvie M; Ware, Cynthia; Melo, Alan L

    2016-01-01

    Species of trematodes belonging to the genus Drepanocephalus are intestinal parasites of piscivorous birds, primarily cormorants (Phalachrocorax spp.), and are widely reported in the Americas. During a 4-year malacological study conducted on an urban lake in Brazil, 27-collar-spined echinostome cercariae were found in 1665/15,459 (10.7 %) specimens of Biomphalaria straminea collected. The cercariae were identified as Drepanocephalus spp. by sequencing the 18S (SSU) rDNA, ITS1/5.8S rDNA/ITS2 (ITS), 28S (LSU) rDNA region, cytochrome oxidase subunit 1 (CO1), and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) markers. In experimental life cycle studies, metacercariae developed in laboratory-reared guppies (Poecilia reticulata); however, attempts to infect birds and rodents were unsuccessful. Two closely related morphotypes of cercariae were characterized. One species, identified by molecular markers as a genetic variant of Drepanocephalus auritus (99.9 % similarity at SSU, ITS, LSU; 97.2 % at CO1; 95.8 % at ND1), differs slightly from an archived North American isolate of this species also sequenced as part of this study. A second species, putatively identified as Drepanocephalus sp., has smaller cercariae and demonstrates significant differences from D. auritus at the CO1 (11.0 %) and ND1 (13.6 %) markers. Aspects related to the morphological taxonomic identification of 27-collar-spined echinostome metacercariae are briefly discussed. This is the first report of the involvement of molluscs of the genus Biomphalaria in the transmission of Drepanocephalus and the first report of D. auritus in South America.

  8. Phylogeography of the Rock Shell Thais clavigera (Mollusca: Evidence for Long-Distance Dispersal in the Northwestern Pacific.

    Directory of Open Access Journals (Sweden)

    Xiang Guo

    Full Text Available The present-day genetic structure of a species reflects both historical demography and patterns of contemporary gene flow among populations. To precisely understand how these factors shape current population structure of the northwestern (NW Pacific marine gastropod, Thais clavigera, we determined the partial nucleotide sequences of the mitochondrial COI gene for 602 individuals sampled from 29 localities spanning almost the whole distribution of T. clavigera in the NW Pacific Ocean (~3,700 km. Results from population genetic and demographic analyses (AMOVA, ΦST-statistics, haplotype networks, Tajima's D, Fu's FS, mismatch distribution, and Bayesian skyline plots revealed a lack of genealogical branches or geographical clusters, and a high level of genetic (haplotype diversity within each of studied population. Nevertheless, low but significant genetic structuring was detected among some geographical populations separated by the Changjiang River, suggesting the presence of geographical barriers to larval dispersal around this region. Several lines of evidence including significant negative Tajima's D and Fu's FS statistics values, the unimodally shaped mismatch distribution, and Bayesian skyline plots suggest a population expansion at marine isotope stage 11 (MIS 11; 400 ka, the longest and warmest interglacial interval during the Pleistocene epoch. The lack of genetic structure among the great majority of the NW Pacific T. clavigera populations may be attributable to high gene flow by current-driven long-distance dispersal of prolonged planktonic larval phase of this species.

  9. 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.

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

    Directory of Open Access Journals (Sweden)

    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. Avaliação das atividades antimicrobiana, citotóxica, moluscicida e antioxidante de Bromelia antiacantha Bertol. (Bromeliaceae Evaluation of antimicrobial, cytotoxic, molluscicidal and antioxidant activities of Bromelia antiacantha Bertol. (Bromeliaceae

    Directory of Open Access Journals (Sweden)

    L.M. Manetti

    2010-12-01

    . The cytotoxic activity evaluated by toxicity bioassay on nauplii of Artemia salina Leach (TAS was positive for both extracts, with LD50 values ranging around 620 µg mL-1 and 360 µg mL-1 for alcoholic extracts from leaves and fruits, respectively. The molluscicidal activity evaluated against Biomphalaria glabrata (Mollusca, Gastropoda did not present acute toxicity for 400 µg mL-1 solutions. The antioxidant properties of the extracts investigated in vitro using the DPPH• method were considered modest (~ 35% of inhibition at 1000 µg mL-1. Among the evaluated biological activities, cytotoxic activity was the most marked.

  12. Avaliação da comunidade de macroinvertebrados aquáticos como ferramenta para o monitoramento de um reservatório na bacia do rio Pitangui, Paraná, Brasil

    Directory of Open Access Journals (Sweden)

    Ivana F Barbola

    2011-06-01

    Full Text Available Os macroinvertebrados bentônicos e nectônicos representam elementos importantes na estrutura e funcionamento dos ecossistemas aquáticos e sua distribuição é influenciada pela natureza química do substrato, composição da vegetação e profundidade da lâmina d'água. O conhecimento desta fauna contribui para a avaliação da qualidade da água e a elaboração de ações visando à conservação da biodiversidade. No presente estudo foram avaliadas diferentes medidas bióticas da comunidade de invertebrados da represa de Alagados, importante manancial da cidade de Ponta Grossa, no Paraná. Em cinco diferentes pontos de amostragem, foram coletados 18.473 exemplares de macroinvertebrados aquáticos ou semi-aquáticos, pertencentes a 46 táxons dos filos Annelida (Hirudinea e Oligochaeta, Mollusca (Gastropoda, Platyhelminthes (Turbellaria, Nematoda e Arthropoda (Arachnida, Crustacea e Insecta. Esta comunidade foi constituída predominantemente por organismos predadores (45,7% dos táxons amostrados, seguidos de coletores e/ou filtradores (23,9%; raspadores (15,2%, fragmentadores (13% e detritívoros (2,2%. De modo geral, os índices de diversidade (H' e equitabilidade (J foram significativamente baixos para os cinco locais investigados, com H' variando de 0,3301 a 1,0396. Quanto à tolerância dos organismos à poluição orgânica, alguns táxons mais sensíveis foram muito raros (Plecoptera ou em baixa frequência (Trichoptera e Ephemeroptera. Entre os grupos mais resistentes a ambientes poluídos estão os Chironomidae e os Hirudinea, ambos bastante comuns nas amostras de Alagados. Este estudo reforça a importância da análise de bioindicadores na avaliação da qualidade de água para consumo humano e também para a conservação de ecossistemas, considerando que um programa de monitoramento ambiental deve integrar medidas físicas, químicas e biológicas.

  13. Toxicity of Nitrate-N to Freshwater Aquatic Life and Its Water Quality Criteria%硝酸盐对淡水水生生物毒性及水质基准推导

    Institute of Scientific and Technical Information of China (English)

    张铃松; 王业耀; 孟凡生; 周岳溪; 于海斌

    2013-01-01

    为推导保护淡水水生生物的NO3-水质基准,收集了NO3-的水生生物毒性数据,然后分析了不同水生生物类群的毒性敏感性,并分别采用评价因子法、毒性百分数排序法和物种敏感度分布法进行基准值推导.结果表明,不同生物类群的水生生物对NO3-毒性的敏感性存在明显差异,其敏感性排序为节肢动物门>软体动物门>脊索动物门;甲壳纲>昆虫纲>腹足纲>双壳>两栖纲>辐鳍纲.3种基准计算方法得到的基准值存在一定差异,最终推荐采用毒性百分数排序法得出的87.97mg·L-1和5.17 mg·L-1为现阶段NO3-(以N计)的水质急性毒性和慢性毒性基准值.%The toxicity sensitivity of different freshwater aquatic organisms was analyzed using the collected toxicity data in this paper.Three methods were used to estimate the criteria of nitrate to protect the freshwater aquatic life.The results showed that the species sensitivity to nitrate followed the order of Arthropoda > Mollusca > Chordata,and Crustacea > Insecta > Gastropoda > Bivalvia >Amphibia > Actinopterygii.Moreover,the output of assessment factor method,species sensitivity distribution method and USEPA's method was significantly different.Finally,criterias of 87.97 mg·L-1 and 5.17 mg· L-1 to protect aquatic life from acute and chronic toxicity were proposed using USEPA's method.

  14. The convoluted evolution of snail chirality

    Science.gov (United States)

    Schilthuizen, M.; Davison, A.

    2005-11-01

    The direction that a snail (Mollusca: Gastropoda) coils, whether dextral (right-handed) or sinistral (left-handed), originates in early development but is most easily observed in the shell form of the adult. Here, we review recent progress in understanding snail chirality from genetic, developmental and ecological perspectives. In the few species that have been characterized, chirality is determined by a single genetic locus with delayed inheritance, which means that the genotype is expressed in the mother's offspring. Although research lags behind the studies of asymmetry in the mouse and nematode, attempts to isolate the loci involved in snail chirality have begun, with the final aim of understanding how the axis of left-right asymmetry is established. In nature, most snail taxa (>90%) are dextral, but sinistrality is known from mutant individuals, populations within dextral species, entirely sinistral species, genera and even families. Ordinarily, it is expected that strong frequency-dependent selection should act against the establishment of new chiral types because the chiral minority have difficulty finding a suitable mating partner (their genitalia are on the ‘wrong’ side). Mixed populations should therefore not persist. Intriguingly, however, a very few land snail species, notably the subgenus Amphidromus sensu stricto, not only appear to mate randomly between different chiral types, but also have a stable, within-population chiral dimorphism, which suggests the involvement of a balancing factor. At the other end of the spectrum, in many species, different chiral types are unable to mate and so could be reproductively isolated from one another. However, while empirical data, models and simulations have indicated that chiral reversal must sometimes occur, it is rarely likely to lead to so-called ‘single-gene’ speciation. Nevertheless, chiral reversal could still be a contributing factor to speciation (or to divergence after speciation) when

  15. Larval trematodes (Digenea of the great pond snail, Lymnaea stagnalis (L., (Gastropoda, Pulmonata in Central Europe: a survey of species and key to their identification

    Directory of Open Access Journals (Sweden)

    Faltýnková A.

    2007-03-01

    Full Text Available A survey of cercariae and metacercariae (Trematoda, Digenea from the great pond snail (Lymnaea stagnalis in Central Europe (Austria, Czech Republic, South-East Germany, Poland and Slovak Republic is presented, based on a study of 3,628 snails examined from 1998 to 2005. A total of 953 (26.3% L. stagnalis were infected with 24 trematode species comprising 19 species of cercariae and 11 species of metacercariae (six species occurred both as cercarie and metacercarie of eight families. The dominant cercariae were those of Opisthioglyphe ranae (159 hosts infected, Plagiorchis elegans (141 (both family Plagiorchiidae and Echinoparyphium aconiatum (153 (Echinostomatidae; 14 double infections were found. The most frequent metacercariae were those of Neoglyphe locellus (71 (Omphalometridae, E. aconiatum (66, Echinostoma sp. (59 and Moliniella anceps (48 (Echinostomatidae. In the previous studies carried out in Central Europe, a very similar spectrum of nine trematode families of 22 cercariae determined to species level and 43 types of cercariae reported under generic or provisional names, which can be in many cases conspecific with the previous taxa, were found. A simple key to identification of cercariae and metacercariae, together with their illustrations, is provided.

  16. Arresting mantle formation and redirecting embryonic shell gland tissue by platinum2+ leads to body plan modifications in Marisa cornuarietis (Gastropoda, Ampullariidae).

    Science.gov (United States)

    Marschner, Leonie; Triebskorn, Rita; Köhler, Heinz-R

    2012-08-01

    To evaluate the threat that anthropogenic substances pose to animals when they are emitted into the environment, tests like the invertebrate embryo toxicity test with the ramshorn snail Marisa cornuarietis have been developed. These tests are used to investigate substances like the heavy metal platinum (Pt) that is used in catalytic converters and is gradually released in car exhausts. In 2010, our group reported that high Pt concentrations cause body plan alterations in snails and prevent the formation of an external shell during M. cornuarietis embryogenesis. Now, this study presents scanning-electron micrographs and histological sections of platinum(2+) (Pt(2+))-treated and untreated M. cornuarietis embryos and compares "normally" developing and "shell-less" embryos during embryogenesis, to reveal the exact course of events that lead to this body plan shift. Both groups showed similar development until the onset of torsion 70- to 82-h postfertilization. In the Pt(2+)-exposed embryos, the rudimentary shell gland (=anlage of both shell gland and mantle, which usually evaginates, grows, and eventually covers the visceral sac) does not spread across the visceral sac but remains on its ventral side. Without the excessive growth of the shell gland, a horizontal rotation of the visceral sac relative to head and foot does not occur, as being normal during the process of torsion.

  17. GENETIC AND MORPHOLOGICAL VARIATION OF POPULATIONS BELONGING TO THE BULINUS TRUNCATUS/TROPICUS COMPLEX (GASTROPODA; PLANORBIDAE) IN SOUTH WESTERN ZIMBABWE

    DEFF Research Database (Denmark)

    Mukaratirwa, S.; Kristensen, Thomas K.; Siegismund, Hans Redlef;

    1998-01-01

    , in respect of allozyme variation (5 polymorphic loci), shell morphology (9 variables), copulatory organ and chromosome number. Comparative data were obtained from snails from north western Zimbabwe identified definitely as B. tropicus. Analysis of the genetic structure revealed a high degree of polymorphism...

  18. Accumulation of free and covalently bound microcystins in tissues of Lymnaea stagnalis (Gastropoda) following toxic cyanobacteria or dissolved microcystin-LR exposure

    International Nuclear Information System (INIS)

    Accumulation of free microcystins (MCs) in freshwater gastropods has been demonstrated but accumulation of MCs covalently bound to tissues has never been considered so far. Here, we follow the accumulation of total (free and bound) MCs in Lymnaea stagnalis exposed to i) dissolved MC-LR (33 and 100 μg L-1) and ii) Planktothrix agardhii suspensions producing 5 and 33 μg MC-LR equivalents L-1 over a 5-week period, and after a 3-week depuration period. Snails exposed to dissolved MC-LR accumulated up to 0.26 μg total MCs g-1 dry weight (DW), with no detection of bound MCs. Snails exposed to MCs producing P. agardhii accumulated up to 69.9 μg total MCs g-1 DW, of which from 17.7 to 66.7% were bound. After depuration, up to 15.3 μg g-1 DW of bound MCs were detected in snails previously exposed to toxic cyanobacteria, representing a potential source of MCs transfer through the food web. - The study concerns accumulation and elimination of both free and bound microcystins (MCs) in tissues of a gastropod exposed to MCs producing cyanobacteria or dissolved MC-LR.

  19. Glowing seashells: diversity of fossilized coloration patterns on coral reef-associated cone snail (Gastropoda: Conidae shells from the Neogene of the Dominican Republic.

    Directory of Open Access Journals (Sweden)

    Jonathan R Hendricks

    Full Text Available The biology of modern Conidae (cone snails--which includes the hyperdiverse genus Conus--has been intensively studied, but the fossil record of the clade remains poorly understood, particularly within an evolutionary framework. Here, ultraviolet light is used to reveal and characterize the original shell coloration patterns of 28 species of cone snails from three Neogene coral reef-associated deposits from the Cibao Valley, northern Dominican Republic. These fossils come from the upper Miocene Cercado Fm. and lower Pliocene Gurabo Fm., and range in age from about 6.6-4.8 Ma. Comparison of the revealed coloration patterns with those of extant species allow the taxa to be assigned to three genera of cone snails (Profundiconus, Conasprella, and Conus and at least nine subgenera. Thirteen members of these phylogenetically diverse reef faunas are described as new species. These include: Profundiconus? hennigi, Conasprella (Ximeniconus ageri, Conus anningae, Conus lyelli, Conus (Atlanticonus? franklinae, Conus (Stephanoconus gouldi, Conus (Stephanoconus bellacoensis, Conus (Ductoconus cashi, Conus (Dauciconus garrisoni, Conus (Dauciconus? zambaensis, Conus (Spuriconus? kaesleri, Conus (Spuriconus? lombardii, and Conus (Lautoconus? carlottae. Each of the three reef deposits contain a minimum of 14-16 cone snail species, levels of diversity that are similar to modern Indo-Pacific reef systems. Finally, most of the 28 species can be assigned to modern clades and thus have important implications for understanding the biogeographic and temporal histories of these clades in tropical America.

  20. DNA sequence characterisation and phylogeography of Lymnaea cousini and related species, vectors of fascioliasis in northern Andean countries, with description of L. meridensis n. sp. (Gastropoda: Lymnaeidae

    Directory of Open Access Journals (Sweden)

    Bargues M Dolores

    2011-07-01

    Full Text Available Abstract Background Livestock fascioliasis is a problem throughout Ecuador, Colombia and Venezuela, mainly in Andean areas where the disease also appears to affect humans. Transmission patterns and epidemiological scenarios of liver fluke infection have shown to differ according to the lymnaeid vector snail species involved. These Andean countries present the vectors Lymnaea cousini, L. bogotensis and L. ubaquensis, unknown in the rest of Latin America. An exhaustive combined haplotype study of these species is performed by means of DNA sequencing of the nuclear ribosomal 18S RNA gene, ITS-2 and ITS-1, and mitochondrial DNA cox1 gene. Results The conserved 5.8S rDNA sequence corroborated that no pseudogenes are involved in the numerous non-microsatellite/minisatellite-related indels appearing between the ITS-2 and ITS-1 sequences when comparing different L. cousini - L. bogotensis populations. Sequence analyses and phylogenetic reconstruction methods including other lymnaeid vector species show that (i L. bogotensis is a synonym of L. cousini, (ii L. ubaquensis is a synonym of Pseudosuccinea columella, and (iii populations of L. cousini hitherto known from Venezuelan highlands indeed belong to a new species for which the name L. meridensis n. sp. is proposed. This new species is described and a complete phenotypic differentiation provided. Conclusions ITS-2, ITS-1 and cox1 prove to be good markers for specimen classification and haplotype characterisation of these morphologically similar lymnaeids in endemic areas. Analysis of the 18S gene and phylogenetic reconstructions indicate that L. cousini and L. meridensis n. sp. cluster in an evolutionary line different from the one of P. columella, despite their external resemblance. This suggests an evolutionary phenotypic convergence related to similar environments and which has given rise to frequent specimen misclassification. Body size and phylogenetic relationships of L. meridensis n. sp. with well-known vectors as Lymnaea cousini and P. columella, as well as with Galba/Fossaria species, suggest that the new species may participate in disease transmission to both animals and humans in altitude areas during the yearly window in which temperatures are higher than the F. hepatica minimum development threshold. The involvement of L. cousini and P. columella in the transmission and geographical/altitudinal distribution of fascioliasis in these Andean countries is analysed.

  1. Phylogenetic relationships elucidate colonization patterns in the intertidal grazers Osilinus Philippi, 1847 and Phorcus Risso, 1826 (Gastropoda: Trochidae) in the northeastern Atlantic Ocean and Mediterranean Sea.

    Science.gov (United States)

    Donald, Kirsten M; Preston, Joanne; Williams, Suzanne T; Reid, David G; Winter, David; Alvarez, Raquel; Buge, Barbara; Hawkins, Stephen J; Templado, Jose; Spencer, Hamish G

    2012-01-01

    Snails in the closely related trochid genera Phorcus Risso, 1826 and Osilinus Philippi, 1847 are ecologically important algal grazers in the intertidal zone of the northeastern Atlantic Ocean and Mediterranean Sea. Here we present the first complete molecular phylogeny for these genera, based on the nuclear 28S rRNA gene and the mitochondrial 16S rRNA and COI genes, and show that the current classification is erroneous. We recognize nine species in a single genus, Phorcus: estimated by BEAST analysis, this arose 30 (± 10) Ma; it consists of two subgenera, Phorcus and Osilinus, which we estimate diverged 14 (± 4.5) Ma. Osilinus kotschyi, from the Arabian and Red Seas, is not closely related and is tentatively referred to Priotrochus Fischer, 1879. Our phylogeny allows us to address biogeographical questions concerning the origins of the Mediterranean and Macaronesian species of this group. The former appear to have evolved from Atlantic ancestors that invaded the Mediterranean on several occasions after the Zanclean Flood, which ended the Messinian Salinity Crisis 5.3 Ma; whereas the latter arose from several colonizations of mainland Atlantic ancestors within the last 3 (± 1.5) Ma. PMID:21945534

  2. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

    Directory of Open Access Journals (Sweden)

    Candia Rowel

    2015-01-01

    Full Text Available This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P<0.001 in both lakes and negative relationship with conductivity (P=0.04 in Lake Albert. Of the Biomphalaria collected in Lake Albert N=6,183, 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria  N=13,172 were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene.

  3. Sclerochronology - a highly versatile tool for mariculture and reconstruction of life history traits of the queen conch, textit{Strombus gigas} (Gastropoda)

    Science.gov (United States)

    Radermacher, Pascal; Schöne, Bernd R.; Gischler, Eberhard; Oschmann, Wolfgang; Thébault, Julien; Fiebig, Jens

    2010-05-01

    The shell of the queen conch Strombus gigas provides a rapidly growing palaeoenvironmental proxy archive, allowing the detailed reconstruction of important life-history traits such as ontogeny, growth rate and growth seasonality. In this study, modern sclerochronological methods are used to cross-date the palaeotemperatures derived from the shell with local sea surface temperature (SST) records. The growth history of the shell suggests a bimodal seasonality in growth, with the growing season confined to the interval between April and November. In Glovers Reef, offshore Belize, the queen conch accreted shell carbonate at rates of up to 6 mm day-1 during the spring (April-June) and autumn (September-November). However a reduced period of growth occurred during the mid-summer months (July-August). The shell growth patterns indicate a positive response to annual seasonality with regards to precipitation. It seems likely that when precipitation levels are high, food availability is increased as the result of nutrient input to the ecosystem in correspondence with an increase in coastal runoff. Slow growth rates occur when precipitation, and as a consequence riverine runoff, is low. The SST however appears to influence growth only on a secondary level. Despite the bimodal growing season and the winter cessation in growth, the growth rates reconstructed here from two S. gigas shells are among the fastest yet reported for this species. The S. gigas specimens from Belize reached their final shell height (of 22.7 and 23.5 cm in distance between the apex and the siphonal notch) at the transition to adulthood in just 2 years. The extremely rapid growth as observed in this species permits detailed, high-resolution reconstructions of life-history traits where sub-daily resolutions can be achieved with ease. The potential for future studies has yet to be further explored. Queen conch sclerochronology provides an opportunity to recover extremely high-resolution palaeotemperature records, which could be used to improve numeric climate models, where the shells essentially function as mineralized buoys. The shell recorder may also help to reveal changes in biogeochemical dynamics in benthic ecosystems on intra-seasonal timescales in the fossil record. Furthermore, sclerochronology provides a rapid, effective and highly versatile investigative strategy when compared to time- and cost-consuming fieldwork for improving fisheries management and maricultural pursuits.

  4. The ultrastructure of the spermatozoon of the ear abalone Haliotis asinina (Gastropoda: Haliotidae)%耳鲍精子的超微结构

    Institute of Scientific and Technical Information of China (English)

    黄勃; 邓中日; 王小兵; 刘均玲; 周智

    2007-01-01

    本文利用透射电子显微镜对耳鲍(Haliotis asinina Linnaeus)精子的形态及超微结构进行了研究.研究结果表明:耳鲍的精子由头部、中段和尾部三部分组成,全长 41.6 μm.精子头部长 1.8 μm,头部由顶体、顶体下腔和细胞核组成,顶体电子密度比较均匀,呈圆锥形,长 0.6 μm,基部宽度为 0.65 μm,占头部长的 1/3;顶体下腔长 0.03 μm,宽为 0.65 μm,腔中含有中等电子密度物质;细胞核圆棒状,长 1.17 μm,核中部的宽度为 1.0 μm.精子中段较短,长 0.51 μm,宽 1.2 μm,主要由 5 个线粒体包围一对中心粒构成.尾部是一根鞭毛,从前到后逐渐变细,鞭毛是由细胞质膜包被的轴丝组成,轴丝为典型的"9+2"微管结构,即轴丝是由两个中心微管及均匀分布在中心微管周围的 9 对双联体微管组成.因此,耳鲍与其它鲍类精子的基本结构相似,形态结构的主要差异表现在三个方面:一是耳鲍精子的头部似圆锥形,长 1.8 μm,是目前已研究的鲍类中头部最短的种类;二是耳鲍精子顶体长比其基部宽要小,顶体电子密度比较均匀,顶体与核的电子密度差异不明显;三是耳鲍精子中段线粒体的数量为 5 个,没有发现 6 个线粒体现象的存在[动物学报 53(3):552-556,2007].

  5. Genus Profundiconus Kuroda, 1956 (Gastropoda, Conoidea: Morphological and molecular studies, with the description of five new species from the Solomon Islands and New Caledonia

    Directory of Open Access Journals (Sweden)

    Manuel J. Tenorio

    2016-01-01

    Full Text Available The genus Profundiconus Kuroda, 1956 is reviewed. The morphological characters of the shell, radular tooth and internal anatomy of species in Profundiconus are discussed. In particular, we studied Profundiconus material collected by dredging in deep water during different scientific campaigns carried out in the Solomon Islands, Madagascar, Papua New Guinea and New Caledonia. We reconstructed a phylogeny of 55 individuals based on partial mitochondrial cox1 gene sequences. The phylogeny shows several clades containing individuals that do not match any of the known species of Profundiconus based on their shell and radular morphologies, and are introduced here as five new species: Profundiconus maribelae sp. nov. from the Solomon Islands; P. virginiae sp. nov. from Chesterfield Plateau (New Caledonia; P. barazeri sp. nov. from Chesterfield Plateau and the Grand Passage area (New Caledonia; P. puillandrei sp. nov. from Norfolk Ridge (New Caledonia, Kermadec Ridge (New Zealand and possibly Balut Island (Philippines; and P. neocaledonicus sp. nov. from New Caledonia. Furthermore, Profundiconus teramachii forma neotorquatus (da Motta, 1984 is raised to specific status as P. neotorquatus (da Motta, 1984.

  6. Hábitos de Vida dos Gastropoda e Bellerophontida da Formação Maecuru,Devoniano Médio, Bacia do Amazonas, Brasil

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    Luiza Corral Martins de Oliveira Ponciano

    2007-07-01

    Full Text Available The Maecuru Formation comprises the Devonian-Carboniferous sedimentary sequence of Amazonas Basin and consists of fluvialdeltaics and pelites layers. Its fossiliferous sediments (the uppermost part of the Lontra Member consists of hummocky cross-stratified fine-grained to very coarse sandstones beds.With the purpose of adding more information about the palaeoecology of The Maecuru Formation fossils, the life habits of gastropods and bellerophontids were inferred based on functional analysis and similarities with the living forms. The more significant features used were: (1 total frontal cross-sectional area, (2height and relative positions of pressure point and center of gravity, (3 apertural margin morphology, (4 kind of symmetry and (5surface smoothness. The species Platyceras (Orthonychia steinmanni; Platyceras (Tumbophalus hartti; Platyceras (Platyostomadarwini; Platyceras (Platyostoma (? agassizi; Platyceras (Orthonychia meerwarthi; Platyceras (Orthonychia gracilis; Platyceras (Tumbophalus coutoanus; “Platyceras” tschernischewi; “Platyceras” subconicum; “Platyceras” (Ortonychia hussaki; “Platyceras” (Ortonychia whitii; “Platyceras” (Ortonychia whitii var. curua and “Platyceras” symmetricum var. maecuruensis represent the epifaunal gastropods with low mobility (coprophagous/suspension feeders of the Maecuru Formation, living symbiotically directly over the anus of a crinoid or nearby. This coprophagous mode of life was probably a non-obligate relationship, because only the closest organisms will get all the advantages of using the crinoid host as a nutrient source. The others adult platyceratids would have a broader feeding repertoire, like as suspension feeders. The bellerophonts Plectonotus (Plectonotus derbyi, Plectonotus (? (Plectonotus salteri e Bucanella reissi would have an epifaunal medium to high mobility, showing a predator habit preferably. On the other hand Bucania freitasi, Ptomatis forbesi and Bellerophon steltzneri showed morphologies compable to a grazer habit with medium mobility. This relative high diversity of gastropods and bellerophonts corroborates the environment of medium and inner shelf inferred for the Maecuru Formation among the others macrofossils, since the majority of Paleozoic fauna of gastropods were typically from shallow seas.

  7. Mother-offspring data in a study of the mating system in a natural population of Bulinus globosus (Gastropoda: Planorbidae) in Zimbabwe

    DEFF Research Database (Denmark)

    Mukaratira, S.; Chandiwana, S.K.; Siegismund, Hans Redlef;

    1996-01-01

    The mating system of a natural population of Bulinus globosus from the Chiweshe area, Zimbabwe, was studied with mother-offspring data using isozyme genetic markers. The study was done in response to work on the genetic structure of this population which suggested a limited extent of cross...

  8. Estado del conocimiento de la durofagia en el registro fósil: interacción depredador-presa en moluscos marinos (Clases Gastropoda y Bivalvia)

    OpenAIRE

    Catalina Gómez-Espinosa; Raúl Gío-Argáez; Miriam Carreño de la Vega

    2015-01-01

    La depredación como un mecanismo evolutivo, de diversificación y biomineralización es un tópico de gran interés. Un tipo específico de depredación es la durofagia que se define como el hábito alimenticio de los animales que consumen organismos con un esqueleto duro mineralizado, ya sea concha o exoesqueleto. Los moluscos representan una fuente muy importante para examinar la depredación durófaga en el registro fósil debido a su distribución mundial, abundancia, buena preservación y a que ...

  9. First molecular identification of Australapatemon burti (Miller, 1923) (Trematoda: Digenea: Strigeidae) from an intermediate host Radix labiata (Rossmaessler) (Gastropoda: Lymnaeidae) in Europe.

    Science.gov (United States)

    Aksenova, Olga V; Bespalaya, Yulia V; Bolotov, Ivan N; Kondakov, Alexander V; Sokolova, Svetlana E

    2016-01-01

    The strigeid digenean species Australapatemon burti (Miller, 1923) (Trematoda: Digenea: Strigeidae) was originally described from North America, but recorded in the Neotropical region (Drago et al. 2007; Hernández-Mena et al. 2014; Blasco-Costa et al. 2016) and in Central Europe (Faltýnková et al. 2007). In Europe, this species is rare, and there is not much information about its range (Faltýnková et al. 2007; Soldánová et al. 2012). Australapatemon burti has a complex life cycle with three larval stages, two of which (sporocyst and cercaria) use several species of freshwater snails, and the third stage (metacercaria) use non-specific host hirudineans (Dubois 1968; Davies & Ostrowski de Núñez 2012; Blasco-Costa et al. 2016). Adult flukes are parasitic in the intenstines of various waterfowl species, such as ducks and swans (Drago et al. 2007; Hernández-Mena et al. 2014). Currently, the molecular data on this parasite species includes only nucleotide sequences of four adult specimens from Mexico (Hernández-Mena et al. 2014). Their hosts were Mexican duck, Anas diazi Ridgway, American Wigeon, Anas americana Gmelin, Cinnamon Teal, Anas cyanoptera Vieillot, and Ruddy Duck, Oxyura jamaicensis (Gmelin) (Anserformes: Anatidae). PMID:27395696

  10. Phylogeography of the Land Snail Eobania vermiculata (O.F. Müller, 1774 (Gastropoda: Pulmonata along the Croatian Coast and Islands

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    Jasna Puizina

    2013-08-01

    Full Text Available Eobania vermiculata (O.F. Müller, 1774, is a typical Mediterranean species of large land snails. Nonindigenous populations of this species, however, are already established in the USA, Australia and elsewhere in the world, where this species is considered to represent a potentially serious threat as a pest and invasive species. The aims of this study were: 1 to determine the pattern of genetic variation within the Croatian E. vermiculata populations based on analyses of sequence diversity of two mitochondrial genes, 16S rDNA and the cytochrome oxidase I (COI, and 2 to shed more light upon the phylogeography of E. vermiculata in this area. Seventy-seven specimens of land snail Eobania vermiculata were sampled at 19 sampling sites along Croatian coastal region and islands. The partial 16S rRNA gene sequences (379 bp grouped into 14 haplotypes, whereas the partial COI gene sequences (523 bp grouped into 13 haplotypes. The overall population is characterized by relatively high haplotype (gene diversity (0.719±0.042 for 16S rDNA and 0.869±0.020 for COI. Demographic Fu F’s tests and Tajima's D value indicated no significant change in the population size, thus suggesting long historical presence of E. vermiculata in this region. Maximum likelihood phylogenetic analysis, Bayesian inference and median joining haplotype network showed a genetic splitting of Croatian 16S rRNA and COI sequences, with a clear distinction between south-Adriatic and north-Adriatic haplotypes. A possible explanation for the observed phylogeography of E. vermiculata, could be related to the climate change, glaciations and the Adriatic Sea level oscillations during the Quaternary

  11. Succinea peruviana (Gastropoda en la dieta de la lagartija de las Lomas Microlophus tigris (Sauria en la Reserva Nacional de Lachay, Lima, Perú

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    José Pérez Z.

    2013-03-01

    Full Text Available El presente trabajo informa de la presencia del caracol Succinea peruviana en la dieta de la lagartija de las Lomas Microlophus tigris, la misma que habita el mesohábitat de Lomas con árboles en la Reserva Nacional de Lachay. Este es el primer informe del consumo de caracoles por lagartijas del Desierto Costero Peruano

  12. Conservation status and updated census of Patella ferruginea (Gastropoda, Patellidae in Ceuta: distribution patterns and new evidence of the effects of environmental parameters on population structure

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    Rivera–Ingraham, G. A.

    2011-06-01

    Full Text Available The Strait of Gibraltar has important populations of the highly endangered patellid limpet Patella ferruginea. Between 2006 and 2010, an exhaustive census was carried out in Ceuta. The total coastline was divided into 17 sectors. The coast of each sector was examined by using 10 m transects. For the case of those sectors composed of breakwaters, jetties or islets, no transects were used, and instead, the total number of individuals was recorded. Each individual was measured to the nearest millimetre using a calliper. Moreover, the complete rocky shore length where the species could potentially be present was calculated, and an estimation of the total number of individuals that each sector could host was made. Results indicate that Ceuta could be home to around 44,000 individuals. The species found in Point Benzú, its westernmost limit of distribution on the North African coasts. The largest populations were recorded on the South Bay, with higher Mediterranean influence. Our results indicate that substrate roughness (topographic heterogeneity and the area’s accessibility highly influence the abundance and population structure. Those populations located on high topographic heterogeneity substrates show higher recruitment rates and lower percentages of larger individuals, while medium to low rugosity surfaces presented the opposite pattern. Additionally, easily accessible areas (and frequented by humans presented smaller average shell sizes. Implications of the results for conservation purposes are discussed.

  13. A new land snail from the Quaternary of Mallorca (Balearic Islands, Western Mediterranean: Darderia bellverica n. gen., n. sp. (Gastropoda, Pulmonata, Helicodontidae

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    Altaba, C. R.

    2006-12-01

    Full Text Available A new genus and species of land snail is described from pre-human paleosoils at Bellver hill in the island of Mallorca. It is a medium-sized helicodontid with 6 tight coils, dome-shaped spire, obtuse peripheral keel, eccentric umbilicus, narrow aperture inclined forward, sinuous reflected peristome, a low angular tooth, 5 infrapalatal denticles, teleoconch with many regular riblets and widely scattered hair pits, and protoconch with simple wrinkles and very thin spiral lines. This very rare species had been reported as a member of the Iberian-Maghribian Oestophora. Similar Plio-Pleistocene fossils from the Balearics and Sardinia are placed in the new genus. This may constitute a biogeographic link within the Lindholmiolinae, now surviving at both ends of the Mediterranean basin. It remains unknown when, why or whether it became extinct.

  14. Population Genetics and Genetic Variability ofBulinus globosus (Gastropoda: Planorbidae) From the Two Main River Systems in Zimbabwe

    DEFF Research Database (Denmark)

    Mukaratirwa, S.; Siegismund, Hans Redlef; Kristensen, Thomas K.;

    1996-01-01

    Bullnus globosus is the only known vector of Schistosoma haematoblum in Zimbabwe. The population genetic structure of this vector snail from the two main river drainage systems, represented by 27 localities, was determined from starch gel lsoenzyme electrophoretic data. Out of 11 enzyme systems s...... of ecological factors (drought/desiccation and floods), genetic drift, and seasonal gene flow as the main factors influencing the genetic structure of these populations.......Bullnus globosus is the only known vector of Schistosoma haematoblum in Zimbabwe. The population genetic structure of this vector snail from the two main river drainage systems, represented by 27 localities, was determined from starch gel lsoenzyme electrophoretic data. Out of 11 enzyme systems...

  15. Biochemical and immunohistochemical analyses of a GnRH-like peptide in the neural ganglia of the Pacific abalone Haliotis discus hannai (Gastropoda).

    Science.gov (United States)

    Amano, Masafumi; Moriyama, Shunsuke; Okubo, Kataaki; Amiya, Noriko; Takahashi, Akiyoshi; Oka, Yoshitaka

    2010-08-01

    We examined whether gonadotropin-releasing hormone (GnRH)-like peptides are present in the neural ganglia of the gastropod Pacific abalone (Haliotis discus hannai) by reverse-phase high performance liquid chromatography (rpHPLC) combined with time-resolved fluoroimmunoassay (TR-FIA) analysis and by immunohistochemistry. Cerebral ganglion extracts showed a similar retention time to lamprey GnRH-II (lGnRH-II) in rpHPLC combined with TR-FIA analysis. GnRH-like-immunoreactive (ir) cell bodies (which reacted with a mouse monoclonal antibody raised against the common amino acid sequence of vertebrate GnRH) were detected in the peripheral region of the cerebral ganglion, and they were observed to send fibers into the neuropil. GnRH-like-ir fibers were also detected in the neuropil of the pedal ganglion, the visceral nerve, and the nerve originating from the pedal ganglion. Chicken GnRH-II (cGnRH-II)-like-ir fibers (which reacted with a rabbit polyclonal antibody raised against cGnRH-II) were also observed in the neuropil of the cerebral ganglion. GnRH-like-ir fibers and cGnRH-II-like-ir fibers were distinguishable in the neuropil of the cerebral ganglion by double-staining immunohistochemistry. These results suggest that multiple GnRH-like peptides exist in the neural ganglia of the Pacific abalone. PMID:20695781

  16. Rapana thomasiana grosse (gastropoda) haemocyanin: spectroscopic studies of the structure in solution and the conformational stability of the native protein and its structural subunits.

    Science.gov (United States)

    Dolashka, P; Genov, N; Parvanova, K; Voelter, W; Geiger, M; Stoeva, S

    1996-04-01

    1. The stability towards pH changes, thermal and chemical (guanidine hydrochloride) denaturation of the oxy- and apo-forms of the native Rapana thomasiana haemocyanin and its structural subunits, RHSS1 and RHSS2, has been investigated using fluorescence and CD spectroscopy. The association of the subunits into haemocyanin aggregates increases considerably the melting temperature and the free energy of stabilization in water. The guanidine hydrochloride denaturation of the aggregated oxygen-transporting protein depends slightly on the protein concentration. The denaturation of the individual subunits is concentration-independent. Rapana haemocyanin is 5.9-7.5 kJ/mol more stable than the constituent polypeptide chains. 2. Upon excitation of the native haemocyanin and the subunits at 295 or 280 nm the fluorescence emission is determined by tryptophyl residues 'buried' deeply in the hydrophobic interior of the protein globules. This is confirmed by quenching experiments with acrylamide, caesium and iodide ions. The efficiency of the radiationless energy transfer between the phenol (donor) and indole (acceptor) fluorophores in the three species, native haemocyanin, RHSS1 and RHSS2, has been determined. An efficient 'interchain' energy transfer between tyrosyl and tryptophyl residues from different polypeptide chains occurs in the non-dissociated form of the haemocyanin. 3. The tryptophan emission of the oxyhaemocyanin, oxy-RHSS1 and oxy-RHSS 2 is strongly quenched by the copper-dioxygen complex at the active site and the respective quantum yields of fluorescence of the oxygenated species are 4-7 times lower than those of the apo-forms. Protonated imidazole groups quench the fluorescence of neighbouring exited indole rings, probably by charge-transfer complex formation. PMID:8670098

  17. Population genetic structure of the freshwater snail, Bulinus globosus, (Gastropoda: Planorbidae) from selected habitats of KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Mkize, Lwamkelekile Sitshilelo; Mukaratirwa, Samson; Zishiri, Oliver Tendayi

    2016-09-01

    The freshwater snail Bulinus globosus is an important intermediate host of Schistosoma haematobium, the causative agent of urinary schistosomiasis. This disease is of major health concern, especially in Africa where the majority of cases have been reported. In this study the inter- and intra-genetic diversity and population genetic structure of B. globosus from nine locations in the KwaZulu-Natal province of South Africa was studied using four polymorphic microsatellite loci (BgZ1-BgZ4). Moderate genetic diversity was detected within populations with a mean diversity (HE) of 0.49±0.09. The majority of populations significantly deviated from Hardy-Weinberg equilibrium (p<0.05), due to a deficit of heterozygotes. Such deviations may be due to founder events that were caused by bottlenecks that occurred as a result of frequent droughts and flooding that these snails' habitats are exposed to. Overall, the populations studied seem to be partially inbreeders/selfers with mean estimates of 0.24/0.38. A discernable genetic structure was elucidated among populations as evident by the mean pairwise FST of 0.58±0.13. There was no significant association between genetic and geographical distance among populations, an indication of limited gene flow. This increases the chances of populations losing alleles due to genetic drift. Populations in close proximity demonstrated high genetic differentiation (58.77% total variation) due to allelic differences between them. The sample populations fell into 12 clusters, however, the populations from uMkhanyakude and uThungulu exhibited no discernable genetic structure. Genetically, the Bhobhoyi site found within the uGu district was equidistant to the two main sampling regions. PMID:27267152

  18. Irrigation canals in Melo creek basin (Rio Espera and Capela Nova municipalities, Minas Gerais, Brazil): habitats to Biomphalaria (Gastropoda: Planorbidae) and potential spread of schistosomiasis.

    Science.gov (United States)

    Leite, M G P; Pimenta, E C; Fujaco, M A G; Eskinazi-Sant'Anna, E M

    2016-04-19

    This study analyzed the presence of Biomphalaria in Melo creek basin, Minas Gerais state, and its relationship to irrigation canals. Seventeen of these canals were used to determine a limnological, morphological and hydrological characterization during an annual seasonal cycle. Biomphalaria samples were sent to René Rachou Research Center/FIOCRUZ for identification and parasitological examination. Six canals were identified as breeding areas for mollusks and in one of them it was registered the coexistence of B. tenagophila (first report to this basin) and B. glabrata species. Results indicated that the low flow rate and speed of water flow were the main characteristics that contributed to this specific growth of the mollusks in the area. These hydraulic characteristics were created due to anthropogenic action through the canalization of lotic areas in Melo creek, which allowed ideal ecological conditions to Biomphalaria outbreak. The results emphasize the need of adequate handling and constant monitoring of the hydrographic basin, subject to inadequate phytosanitary conditions, aiming to prevent the occurrence and propagation of schistosomiasis. PMID:27097093

  19. INTRODUCTION After fourteen years of pioneering systematic work spanning from 1996 to 2010, carried out in the territory of Santa Catarina State, SC, within the Brazilian Southern region, framed in the socalled Atlantic Slope of the Southern Cone of South America (Agudo-Padrón, 2008a, a basic list of continental (land and freshwater and marine mollusc species was compiled. Besides constant interactions and consultations with numerous national and international specialists, such a list was mostly based on available literature and/or analyses of voucher specimens deposited in collections belonging to research centers or environmental education institutes. To date (up to the first semester of 2010, this list comprises a total of 878 taxa (species and subspecies, including 695 marine and 183 continental forms, and these numbers are likely to increase as field surveys ensue. In the present study, results obtained from the author’s active participation in three recent regional field sampling expeditions dealing with marine and continental mollusc taxa, are reported. I. Official State program for listing and control of invasive exotic species Starting from November 2009, and for the first time in the history of Santa Catarina State, the presence of invasive allochthonous mollusc species in Santa Catarina State was studied and discussed through the organisation of seminars by the Official Foundation for the Environment of the State of Santa Catarina (Fundação do Meio Ambiente – FATMA jointly with the Hórus Institute for Development and Environmental Conservation (Instituto Hórus de Desenvolvimento e Conservação Ambiental, with the main goal to compile the Official State List of Species. To date, the occurrence of a total of twenty allochthonous (exotic forms of mollusc species has been confirmed, 14 Gastropoda and 6 Bivalvia [namely, 11 terrestrial gastropods, 5 freshwater taxa (3 gastropods and 2 bivalves and 4 marine bivalves]. Taking into account the

    Directory of Open Access Journals (Sweden)

    A. Ignacio Agudo-Padrón

    2011-03-01

    Full Text Available Available knowledge of malacofauna (mollusc species conservation in the territory of Santa Catarina State,SC, central Southern Brazil region, is shortly analyzed and discussed herein. Present data originate from theauthor's active participation in three recent regional unpublished events dealing with biodiversity conservationin the State, carried out to cope the sensitive lack of population studies which is the main difficulty to face inorder to provide accurate and detailed evaluations on biodiversity and its conservation status.

  20. Taxocenosis of mollusks and crustaceans on roots of Rhizophora mangle (Rhizophoraceae at Cispatá Bay, Córdoba, Colombia

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    Jorge Alexander Quirós R

    2013-05-01

    Full Text Available Despite the existing knowledge on the ecology of mangroves at Cispatá Bay, few studies have focused on the association of invertebrates on red mangrove roots, so between December 2010 and September 2011, it was characterized taxocenosis of mollusks and crustaceans on roots of Rhizophora mangle in two study sites at Cispatá Bay, Colombia. For the collections of biological material were randomly taken three red mangrove roots with a diameter. Mollusks and crustaceans were obtained from the root surface with a scraping knife then were removed and fixed in 10 % formalin for later identification to species using specialized taxonomic keys. Of the 12289 individuals collected in the four samples, 10470 belonged to the phylumMollusca (85,2 % and the remaining 1819 to subphylum Crustacea (14,8 %. For mollusks were identified 14 species distributed in 11 families and two classes; Bivalvia and Gastropoda. For crustaceans were identified 24 species distributed in 16 families and four orders; Sessillia, Decapoda, Isopoda and Amphipoda. In both sectors sampling Mytella charruana, Balanus eburneusand Crassostrea rhizophorae were the most important species in terms of abundance, however mollusks like M. charruana and B. eburneus have a great ability to adapt and adjust to changing hydroclimatic, which was reflected in the dominance of these species in the sector with the greatest influence Sinu River. The presence of crustaceans Petrolisthes armatus and Aratus pisonii in the sector with more proximity to the Caribbean Sea indicate that are species with great mobility and physiological adaptation mechanisms.TAXOCENOSIS DE MOLUSCOS Y CRUSTÁCEOS EN RAÍCESDE Rhizophora mangle (RHIZOPHORACEAEEN LA BAHÍA DE CISPATÁ, CÓRDOBA, COLOMBIAA pesar del conocimiento existente sobre la ecología de los manglares en la bahía de Cispatá, pocos estudios han sido enfocados en invertebrados asociados a las raíces del mangle rojo. Entre diciembre 2010 y