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Sample records for opisthobranchia gastropoda mollusca

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

    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.

    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).

    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

    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).

    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.

    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

    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)

    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).

    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. Babosas terrestres (Mollusca, Gastropoda) de la Región de Murcia (SE España)

    Borredà, V.; Martínez–Ortí, A

    2014-01-01

    Terrestrial slugs (Mollusca, Gastropoda) from Murcia (SE Spain) This study examines the few citations about terrestrial slugs from Murcia (SE Spain) and adds data from our own surveys. We provide a systematic checklist of the species of terrestrial slugs known from Murcia (SE Spain) and comment on the most significant species: Deroceras nitidum, Arion gilvus and A. lusitanicus s. l.

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

    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

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

    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.

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

    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

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

    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

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

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

    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...

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

    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

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

    Kristof, Alen; Klussmann-Kolb, Annette

    2010-01-01

    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, A. stephanieae shows some features shared by all nudibranchs like the postmetamorphic condensation of the CNS, the possession of...

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

    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.

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

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

    2008-01-01

    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...

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

    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

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

    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

  3. Effects of thermal effluents on the population dynamics of Physa gyrina Say (Mollusca: Gastropoda) at Lake Wabamun, Alberta

    Effects of thermal effluents on the population dynamics of Physa gyrina Say (Gastropoda: Pulmonata) were studied at Lake Wabamun, Alberta, from May 1971 to August 1973. Thermal effluent increased the rate of development of eggs and the growth of P. gyrina, and allowed continuous reproductive activity throughout the year. These changes, and the increased period of growth of aquatic macrophytes, resulted in increased population densities of P. gyrina in the heated area during summer. Temperatures below 10 deg C or small amounts of vegetation appear to limit the population of P. gyrina in winter. (author)

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

    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

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

    Abraham Breure

    2013-03-01

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

  6. Two new sacoglossans (Gastropoda: Opisthobranchia) from Thailand

    Swennen, C.

    2001-01-01

    Two new sacoglossans were found in brackish mangrove habitats near Pattani in the southern part of the Gulf of Thailand. Both are small species (< 10 mm) living hidden in clay with small green algae high in the intertidal zone becoming not submerged for days. They have black pigment on the dorsal side and their bodies clearly consist of two parts. One is named Gascoignella nukuli n. sp., which looks similar to G. aprica Jensen, 1985 from Hong Kong, but differs in radula, penial spine, body...

  7. Effects of thermal effluents on parasites and commensals of Physa gyrina Say (Mollusca: Gastropoda) and their interactions at Lake Wabamun, Alberta

    Sankurathri, C.S. (Dept. of the Environment, Nanaimo, British Columbia); Holmes, J.C.

    1976-10-01

    Effects of thermal effluents on the dynamics of larval helminth parasites and on populations of limnaei haetogaster limnaei limnaei and Chaetogaster limnaei vaghini (Annelida; Oligochaeta) harbored by Physa gyrina (Mollusca: Pulmonata) were studied at Lake Wabamun, Alberta. Thermal effluents provided the necessary conditions to maintain digenean parasite transmission throughout the year between definitive and intermediate hosts, and increased the prevalence of certain parasites, especially the metacercarial stages. At temperatures above 24/sup 0/C prevalences of C. l. limnaei and C. l. vaghini decreased in the lake, and at these temperatures in the laboratory C. l. limnaei abandoned the snails and perished. Under experimental conditions the number of Echinoparyphium recurvatum larvae penetrated Physa gyrina was inversely related to the number of C. l. limnaei present. It was also observed that these oligochaetes actively ingested digenean larvae. Elimination of C. l. limnaei caused by thermal effluents has augmented the metacercarial infections. An ecological model depicting the interactions of Physa gyrina--digeneans--Chaetogaster l. limnaei is presented. This is a complex system in which water temperature acts as a main regulating factor. The three main components of the system interact with each other and are influenced by various external factors, resulting in a dynamic ecological system.

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

    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. TALASOZOONIMI U "LAXICON LATINO–ILLYRICUM" PAVLA VITEZOVIĆA II. NAZIVLJE MOLLUSCA

    Meštrović, Zrnka

    1993-01-01

    U članku se analizira nazive Mollusca (Cephalopoda, Gastropoda i Lamellibranchiata) iz Vitezovićeva Lexicona s međe sedamnaestoga na osamnaesto stoljeće, i to s referencijalnog, s onomastičkog i, koliko je moguće, s etimološkog gledišta.

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

    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.

  11. FRESHWATER SNAILS (MOLLUSCA: GASTROPODA) OF NORTH AMERICA

    Freshwater gastropod mollusks are represented in North America (north of Mexico) by 15 families, 78 genera and, as treated in this manual, 499 species. They are grouped into two large subclasses, the gill-breathing, operculated Prosobranchia and the lung-breathing, non-operculate...

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

    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

  13. Accumulation of cesium-137 by useful mollusca

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

  14. Metabolism of 60Co in mollusca

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

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

    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

  16. Mollusca contagiosa

    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...

  17. ВОЗРАСТНАЯ СТРУКТУРА ПОПУЛЯЦИИ ВИНОГРАДНОЙ УЛИТКИ HELIX POMATIA ( MOLLUSCA, GASTROPODA) И ВЛИЯНИЕ НА НЕЕ ЭКСПЛУАТАЦИИ

    Румянцева, Е.

    2003-01-01

    Встановлено, що в Калінінградській обл. структура популяції Helix pomatia ( Mollusca, Gastropoda ) зазнає значних змін під впливом експлуатації: зменшується доля новонарджених особин, знижується кількість виловлюваних вікових груп, змінюється вікова структура популяції в цілому.

  18. Karakteristik Fisika-Kimia Perairan Dan Struktur Komunitas Moluska (Bivalvia Dan Gastropoda) Di Pantai Cermin Sumatera Utara

    Siregar, Raissha Amanda

    2014-01-01

    RAISSHA AMANDA SIREGAR, Physical and Chemical Characteristics of Aquatic and Community structures Many activities around Cermin Beach feared of mollusca (bivalvia and gastropoda) in Cermin Beach, North Sumatera. Under guided YUNASFI and ANI SURYANTI. can alter the water quality of Cermin Beach. Information and understanding of environmental change is indispensable in ecosystem monitoring efforts. This research aims to determine the status of the water quality seen on characteristics of chemic...

  19. Miocene Vetigastropoda and Neritimorpha (Mollusca, Gastropoda) of central Chile

    Nielsen, Sven N.; Frassinetti, Daniel; Bandel, Klaus

    2004-09-01

    Species of Vetigastropoda (Fissurellidae, Turbinidae, Trochidae) and one species of Neritimorpha (Neritidae) from the Navidad area, south of Valparaı´so, and the Arauco Peninsula, south of Concepción, are described. Among these, the Fissurellidae comprise Diodora fragilis n. sp., Diodora pupuyana n. sp., two additional unnamed species of Diodora, and a species resembling Fissurellidea. Turbinidae are represented by Cantrainea sp., and Trochidae include Tegula (Chlorostoma) austropacifica n. sp., Tegula (Chlorostoma) chilena n. sp., Tegula (Chlorostoma) matanzensis n. sp., Tegula (Agathistoma) antiqua n. sp., Bathybembix mcleani n. sp., Gibbula poeppigii [Philippi, 1887] n. comb., Diloma miocenica n. sp., Fagnastesia venefica [Philippi, 1887] n. gen. n. comb., Fagnastesia matanzana n. gen. n. sp., Calliostoma mapucherum n. sp., Calliostoma kleppi n. sp., Calliostoma covacevichi n. sp., Astele laevis [Sowerby, 1846] n. comb., and Monilea riorapelensis n. sp. The Neritidae are represented by Nerita (Heminerita) chilensis [Philippi, 1887]. The new genus Fagnastesia is introduced to represent low-spired trochoideans with a sculpture of nodes below the suture, angulated whorls, and a wide umbilicus. This Miocene Chilean fauna includes genera that have lived at the coast and in shallow, relatively warm water or deeper, much cooler water. This composition therefore suggests that many of the Miocene formations along the central Chilean coast consist of displaced sediments. A comparison with different fossil and Recent faunas from around the Pacific and South America indicates that the vetigastropod and neritid fauna from the Miocene of Chile has only minor affinities with taxa living near New Zealand, Argentina, and the tropical eastern Pacific at that time.

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

    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 ...

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

    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.

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

    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

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

    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...

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

    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

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

    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.

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

    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

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

    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

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

    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

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

    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

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

    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

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

    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.

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

    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

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

    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

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

    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

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

    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.

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

    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

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

    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

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

    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

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

    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

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

    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...

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

    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

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

    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

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

    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.

  4. From Polyplacophora to Cephalopoda: comparative analysis of nitric oxide signalling in mollusca.

    Moroz, L L; Gillette, R

    1995-01-01

    The distribution of putative nitric oxide synthase (NOS)-containing cells has been analysed using NADPH-d histochemistry in the CNS and peripheral tissues in more than 2D ecologically and systematically different molluscan genera representing 3 main classes of the phylum MOLLUSCA: Polyplacophora (Lepidopleurus, Lepidozona, Katharina), Gastropoda (Littorina, Lymnaea, Aplexa, Physa, Planorbarius, Planorbis, Helisoma, Biomphalaria, Helix, Limax, Cepaea, Bulla, Aplysia, Phyllaplysia, Philine, Pleurobranchea, Tritonia, Armina, Flabellina, Cadlina) and Cephalopoda (Octopus, Sepia, Rossia, Loligo). Several species were used for more detailed immunohistochemical, biochemical, biophysical and physiological studies to further assay of NOS activity and to analyse functional roles of nitric oxide (NO) in these animals. The main conclusions of our comparative analysis and literature survey can be summarised as following: (i) There is strong evidence for the presence of NO-dependent signalling pathways in different molluscan species. (ii) We hypothesise that a general tendency in the evolution of NADPH-d-reactive cells in Mollusca is a migration of nitrergic function from periphery to the CNS. Also, different isoforms of NOS appear to be present in any one species. (iii) One of the main functional targets of NO signalling is the feeding system. However, there are obvious differences between predators (many labelled central motoneurons) and herbivorous species (many labelled peripheral putative sensory cells) as well as between land/freshwater and marine animals. Nevertheless, in all species tested NO-activated feeding-like motor patterns in the buccal ganglia. Additional functional and cellular targets for NO in molluscs are also considered. We briefly review neuromodulatory mechanisms of NO action and we consider molluscs as useful model systems for investigations of the roles of NO. PMID:8853687

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

    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 U......-shaped cross-section. Originally, these were parallel slits opening on the ventral surface of the carapace. Lobation of the posterior margin of the carapace, of unusually large mature size for the group, make the animal different from other members of Halicynidae, and the new name Opolanka decorosa gen. et sp...... cuticle, with strongly calcified rigid dorsal parts suspended from the carapace. At least three ecologically and anatomically distinct lineages were represented in the order Cyclida, which was probably initially confined to marine environments and gradually adapted to life in continental waters. New taxa...

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

    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

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

    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

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

    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.

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

    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

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

    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

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

    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

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

    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

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

    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

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

    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...

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

    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.

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

    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.

  17. A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia

    Whisson, Corey S.; Breure, Abraham S.H.

    2016-01-01

    Abstract Bothriembryon sophiarum sp. n. is described, based on shell and anatomical morphology, from the coastal area of south-easternmost Western Australia. This is the first description of a new extant Australian bothriembryontid in 33 years. The shell of Bothriembryon sophiarum is slender with a unique teleoconch sculpture. It is found in low coastal scrub on cliff edges and escarpments and because of its restricted distribution, qualifies as a short range endemic. PMID:27199583

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

    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

  19. DNA barcoding reveals neritid diversity (Mollusca: Gastropoda) diversity in Malaysian waters.

    Chee, S Y; Mohd Nor, Siti Azizah

    2016-05-01

    This is the first study to identify and determine the phylogenetics of neritids found in Malaysia. In total, twelve species from the family Neritidae were recorded. Ten species were from the genus Nerita and two species were from the genus Neritina. DNA barcodes were successfully assigned to each species. Although some of these species were previously reported in the region, three are only presently reported in this study. The dendrogram showed Nerita and Neritina strongly supported in their respective monophyletic clades. Phylogenetic positions of some species appeared unstable in the trees. This could be due to the differences in a small number of nucleotides, thus minimizing genetic variation between each specimen and species. PMID:25471442

  20. Caribbean Bulimulus revisited: physical moves and molecular traces (Mollusca, Gastropoda, Bulimulidae).

    Breure, Abraham S H

    2016-01-01

    Twenty-five samples of Bulimulus species are studied, partly from localities within their known distribution range, partly based on interceptions where the material originates from localities where the species seem to be recently introduced and non-native. Molecular study of cytochrome oxidase 1 (CO1) reveals the origin of some of these introductions, but is less conclusive for others. Four different methods for species delimitation were applied, which did not result in unambiguous species hypotheses. For a rapid identification of morphologically indistinct species, a more comprehensive database of sequences is needed. PMID:27069787

  1. Response of the Lymnaea peregra (Mollusca: gastropoda) to oil and dispersant

    The effects of oil polluted water (heavy fuel oil) and a dispersant (Finasol OSR 5) on the behavior of Lymnaea peregra were tested in 4 l aquaria (static test, 96 h, no food added, surface oil slick not removed, water temp. +20 and S 4.5 o/oo). The accumulation of oil in the tissues of the snails was also studied. The activity in oil polluted water low (10 %) compared with the control (30 %). The mortality was 10 % in the oil polluted water and 0 % in the control. In the test with the dispersant (0.01 vol-%), the activity of the snails was 10 % compared with 40 % in the control. The mortality increased from 0 - 20 %. Snails exposed to oil mixtures of 0.1 and 10 vol-% showed increased concentrations of aliphatic and aromatic hydrocarbons in their tissues (4 - 20 times higher than in the control)

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

    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.

  3. A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia.

    Whisson, Corey S; Breure, Abraham S H

    2016-01-01

    Bothriembryon sophiarum sp. n. is described, based on shell and anatomical morphology, from the coastal area of south-easternmost Western Australia. This is the first description of a new extant Australian bothriembryontid in 33 years. The shell of Bothriembryon sophiarum is slender with a unique teleoconch sculpture. It is found in low coastal scrub on cliff edges and escarpments and because of its restricted distribution, qualifies as a short range endemic. PMID:27199583

  4. Effects of crude oil on the behavior of Lymnaea peregra (Mollusca: gastropoda)

    The effects of oil polluted water (crude oil) on the behavior of L. pereqra were tested (4 l aquaria, static test, 96 h, no food added, surface slick not removed, water temp. +17 S deg C, S 4 o/oo, 3 parallel test/conc, 10 - 15 ind./aquaria). The activity of the snails was measured 3 times a day by counting the proportion of individuals crawling around within one minute. The activity of the snails was negatively affected in oil solutions of 0.1 to 1.0 vol-%. In the 1 vol-% oil solution the snails were paralysed after being exposed for 24 h and they were unable to crawl around for the next 24 h. The reproduction of the snails (egg laying) was negatively affected by oil. In the excrements of the snails small oil balls could be seen, more in the 0.1 vol-% solution than in the 1 vol-% solution. The mortality was two times higher in the 1 vol-% solution (40 %) than in the control (18 %)

  5. Anatomia e histologia do conduto genital feminino de Pomacea canaliculata (Lamarck, 1822 (Mollusca, Gastropoda, Pilidae

    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.

  6. The Vermetidae of the Gulf of Kachchh, western coast of India (Mollusca, Gastropoda).

    Joshi, Devanshi MukundRay; Mankodi, Pradeep C

    2016-01-01

    Coral reefs are often termed underwater wonderlands due to the presence of an incredible biodiversity including numerous invertebrates and vertebrates. Among the dense population of benthic and bottom-dwelling inhabitants of the reef, many significant species remain hidden or neglected by researchers. One such example is the vermetids, a unique group of marine gastropods. The present study attempts for the first time to assess the density and identify preferred reef substrates in the Gulf of Kachchh, state of Gujarat, on the western coast of India. A total of three species of the family Vermetidae were recorded during the study and their substrate preferences identified. PMID:26877684

  7. Quantification of midkine gene expression in Patella caerulea (Mollusca, Gastropoda) exposed to cadmium

    Stillitano, Francesca; Mugelli, Alessandro; Cerbai, Elisabetta; Vanucci, Silvana

    2007-10-01

    The release of cadmium into many coastal areas represents a threat to ecosystems and human health; cadmium is carcinogenic in mammals and in both marine invertebrates and vertebrates. The use of molluscs to assess the ecologic risk associated with contaminants is strongly recommended on account of their ecological role and on their highly conserved control and regulatory pathways that are often homologous to vertebrate systems. We previously identified a midkine family protein in the limpet Patella caerulea; the midkine is a recently discovered cytokines family with unequivocal informative value on repairing injury and neoplastic processes in mammals. Here we report on midkine ( mdk) and α-tubulin ( α-tub) gene expression patterns in P. caerulea exposed to cadmium. Limpets, collected on two occasions from a breakwater at a marina (Tyrrhenian Sea) were exposed to sublethal cadmium concentrations (0.5 and 1 mg l -1 Cd) over a 10-day exposure period. RNA was extracted from the viscera of unexposed and exposed specimens. Real time TaqMan RT-PCR was performed to measure the relative mdk and α-tub gene expression levels. A remarkable mdk over-expression was observed in all exposed animals with respect to unexposed ones; mdk over-expression was significantly higher in both treatments when compared with un-treatment (mean expression levels: 23- and 38-fold, for 0.5 and 1 mg l -1 Cd treatment, respectively; ANOVA, for both P < 0.01). The study also indicates that the mdk up-regulation was significantly Cd-concentration dependent ( P < 0.05). A significant up-regulation of the constitutive α-tub gene was also observed in 1 mg l -1 Cd-treated animals (mean expression level: 4-fold; ANOVA, P < 0.05). In conclusion, these data provide the first evidence paving the way for the use of the midkine as a promising new biomarker of effect in the environment risk assessment policy.

  8. Effect of 60 Co gamma radiation on Biomphalaria Glabrata (Mollusca, Gastropoda) embryos: mortality, malformation and hatching

    A study was carried out on the radiosensitivity of Biomphalaria glabrata embryos submitted to doses of 5, 10, 15, 20 and 25 Gy of 60 Co during the cleavage, blastula, gastrula, young trochophore and trochophore stages. Mortality, malformation and hatching were the parameters used to evaluate the damage induced by ionizing radiation. Estimated L D50 values (15 days) showed that the cleavage stage (4.3 Gy) was approximately four times more radiosensitive than the trochophore stage (17.0 Gy). Susceptibility to malformation induction was higher in the blastula, gastrula and young trochophore stages. Several types of morphogenetic malformations were observed, such as head malformations, exogastrulas, shell malformations, and embryos with everted stomodeum, with nonspecific malformations being the most frequent. The types of malformation induced by radiation probably are not radiation-specific and do not depend on the dose applied. The dose of 15 Gy was sufficient to greatly reduce the number of hatching snails regardless of the embryonic stage irradiated. We conclude that the effect of 60 Co gamma radiation on B. glabrata embryos presented a specific pattern. (author)

  9. Rich and rare—First insights into species diversity and abundance of Antarctic abyssal Gastropoda (Mollusca)

    Schwabe, Enrico; Michael Bohn, Jens; Engl, Winfried; Linse, Katrin; Schrödl, Michael

    2007-08-01

    The abyssal depths of the polar oceans are thought to be low in diversity compared with the shallower polar shelves and temperate and tropical deep-sea basins. Our recent study on the gastropod fauna of the deep Southern Ocean gives evidence of the existence of a rich gastropod assemblage at abyssal depths. During the ANDEEP I and II expeditions to the southern Drake Passage, Northwestern Weddell Sea, and South Sandwich Trench, gastropods were collected by bottom and Agassiz trawls, epibenthic sledge, and multicorer, at 40 stations in depths between 127 and 5194 m. On the whole, 473 specimens, corresponding to 93 species of 36 families, were obtained. Of those, 414 specimens were caught below 750 m depth and refer to 84 (90%) benthic species of 32 (89%) families. Most families were represented by a single species only. The numerically dominant families were Skeneidae and Buccinidae (with 10 and 11 species, respectively), Eulimidae and Trochidae (with 9 species each), and Turridae (6 species). Thirty-Seven benthic deep-sea species (44%) were represented by a single specimen, and another 20 species (24%) were found at a single station, suggesting that more than two thirds of Antarctic deep-sea gastropod species are very rare or have a very scattered distribution. Of the 27 species occurring at two or more deep-sea stations, 14 were collected with different gear. Approximately half of the deep-water species are new to science or have been recently described. The present investigation increases the total number of recorded benthic Antarctic deep-sea gastropods (below 750 m) from 115 to 177. The previously known depth ranges have been extended, often considerably, for 31 species. The collected deep-sea gastropods comprise both eurybathic shelf species (29%) and apparently true deep-sea species (58%); some of the latter may belong to a so far unknown Antarctic abyssal fauna. Geographical ranges of the collected Antarctic benthic deep-sea gastropod species appear limited, and all these 84 species seem endemic to Antarctica south of the Polar Front. Comparing diversity and abundances based on epibenthic sledge samples, there is no clear relationship between Antarctic deep-sea gastropod abundance and species richness with depth. However, both Antarctic and adjacent deep-sea areas are still far from being adequately sampled to allow more comprehensive conclusions.

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

    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.

  11. A new Middle Miocene Niveria Jousseaume, 1884 (Mollusca: Gastropoda: Trivioidea) from Hungary

    Fehse, Dirk

    2011-02-01

    A new species of Niveria from the Middle Miocene (Badenian) of the Paratethys of Borsodbóta, Hungary is described. This species is characterized by its callused dorsum and dorsal depression. Niveria jozefgregoi sp. nov. is discussed with comparative species from the Badenian of Hungary, the Pliocene of the Mediterranean region, Florida and Recent species from Madeira and the Islas Galápagos.

  12. Dating and biogeographical patterns in the sea slug genus Acanthodoris Gray, 1850 (Mollusca, Gastropoda, Nudibranchia).

    Hallas, Joshua M; Brian Simison, W; Gosliner, Terrence M

    2016-04-01

    Recent studies investigating vicariance and dispersal have been focused on correlating major geological events with instances of taxonomic expansion by incorporating the fossil record with molecular clock analyses. However, this approach becomes problematic for soft-bodied organisms that are poorly represented in the fossil record. Here, we estimate the phylogenetic relationships of the nudibranch genus Acanthodoris Gray, 1850 using three molecular markers (16S, COI, H3), and then test two alternative geologically calibrated molecular clock scenarios in BEAST and their effect on ancestral area reconstruction (AAR) estimates employed in LAGRANGE. The global temperate distribution of Acanthodoris spans multiple geological barriers, including the Bering Strait (∼5.32Mya) and the Baja Peninsula (∼5.5Mya), both of which are used in our dating estimates. The expansion of the Atlantic Ocean (∼95-105Mya) is also used to calibrate the relationship between A. falklandica Eliot, 1905 and A. planca Fahey and Valdés, 2005, which are distributed in southern Chile and South Africa respectively. Phylogenetic analyses recovered strong biogeographical signal and recovered two major clades representing northern and southern hemispheric distributions of Acanthodoris. When all three geological events are applied to the calibration analyses, the age for Acanthodoris is estimated to be mid-Cretaceous. When the expansion of the Atlantic Ocean is excluded from our analyses, however, Acanthodoris is estimated to be much younger, with a divergence time estimate during the Miocene. Regardless of divergence estimates, our AAR suggests that Acanthodoris may have origins in the Atlantic Ocean with the Atlantic acting as a dispersal point to the northeastern Pacific. These results suggest that Acanthodoris exhibits a rare instance of western trans-arctic expansion. This study also shows that northeast Pacific specimens of A. pilosa should be regarded as A. atrogriseata and that A. serpentinotus should be regarded as a synonym of A. pina. PMID:26752594

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

    1980-01-01

    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 refer...

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

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

    1997-06-01

    Achatina fulica, the intermediate snail host of angiostrongyliasis and also an agricultural pest, is being bred in Brazil for human consumption as "escargot". The snail has escaped from its artificial breeding sites and its dispersal in Itariri country, State of S. Paulo, is reported here for the first time. A. fulica is a transmitter of the rat lungworm Angiostrongylus cantonensis, nematode which causes meningoencephalic angiostrongyliasis; the risks of human contamination are commented on. PMID:9515269

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

    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.

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

    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.

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

    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.............

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

    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

  19. Ciliary ultrastructure of polyplacophorans (Mollusca, Amphineura, Polyplacophora).

    Lundin, K; Schander, C

    2001-01-01

    This study is part of a series of papers aiming to investigate the phylogenetic significance of ciliary ultrastructure among molluscs and to test the hypothesis of a relationship between Xenoturbella and the molluscs. The ultrastructure of the ciliary apparatus on the gills of the polyplacophorans Leptochiton asellus and Tonicella rubra was studied. The gill cilia of the two species are similar in shape. The free part of the cilium is long with a slender distal part. There are two ciliary rootlets. One of them is short, broad and placed on the anterior face of the basal body. The other rootlet is conical and has a vertical orientation. Among the mollusca, two ciliary rootlets in the ciliary apparatus of multiciliate ectodermal cells have only been reported from the Chaetodermomorpha and Neomeniomorpha. This character state is likely plesiomorphic for the Mollusca and indicates a basal (nonderived) position of these taxa among the molluscs. No possible synapomorphic character with Xenoturbella bocki was found. PMID:11686414

  20. De weekdieren van de Nederlandse brakwatergebieden (Mollusca)

    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. In this paper a review is presented of the molluscs living in brackish waters in the Netherlands. All available data from literature, collections, literature and databanks were compiled for this cau...

  1. HOW DOES HACCP CHANGE U.S. SEAFOOD EXPORTS?-ANALYSIS WITH FISHES, MOLLUSCA, AND SHELLFISH OTHER THAN MOLLUSCA

    Li, Xiaoqian; Saghaian, Sayed H.

    2012-01-01

    Although the effect of HACCP on international trade is an issue with many concerns recently, only a few empirical studies focus on the impact of HACCP on U.S seafood export industry. Using the approach of Gravity Model with adjustment of unobserved country characteristics, this paper contributes to analyze the differential effects of HACCP implementation on three kinds of seafood: fishes, mollusca, and shellfish other than mollusca. The results indicate that HACCP application has negative but...

  2. Rasprostranjenost roda Zospeum Bourguignat 1856 (Gastropoda, Ellobiidae) u Hrvatskoj

    Slapnik, R.; Ozimec, R.

    2004-01-01

    Rad je prinos poznavanju zemljopisnog rasprostranjenja troglobiontnih puževa iz roda Zospeum Bourguignat 1856 (Gastropoda, Pulmonata, Ellobiidae) na području krša Hrvatske. Navedena su nalazišta pojedinih svojti uz prikaz areala na UTM karti Hrvatske. Utvrđeno je šest vrsta i dvije podvrste.

  3. Evolution of shell loss in Opisthobranch gastropods: sea hares (Opisthobranchia, Anaspidea) as a model system

    Vue, Zer

    2009-01-01

    Due to the advantages of the hard, calcifying shell, the Mollusca are one of the most successful animal phyla. The shell forms during embryonic and larval development; however, many molluscan groups have a highly reduced shell or have lost it completely as development and maturation proceeds. These major developmental transitions in shell morphology frequently correlate with ecological transitions (e.g. diet change/change from planktonic to bethic existence pre- and post-met...

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

    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

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

    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.

  6. 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).

    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

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

    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

  8. 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

    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.

  9. 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

    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

  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

    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. 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

    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.

  12. Prosobrânquios terrestres do Brasil: Cyclophoridae: Neocyclotus (N. agassizi (Bartsch & Morrison, 1942 (Mollusca, Gastropoda, Mesogastropoda Land prosobranchs of Brazil: Cyclophoridae: Neocyclotus (N. agassizi (Bartsch & Morrison, 1942 (Mollusca, Gastropoda, Mesogastropoda

    Arnaldo C. dos Santos Coelho

    1989-01-01

    Full Text Available Studies on specimens from Brazil (States of Pernambuco and Alagoas were carried out in order to relate data about morphology of hard and soft parts o Nocyclotus (N. agassizi (Bartsh & Morrison, 1942.

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

    Horácio Manuel Santana Teles

    1997-06-01

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

  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

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

    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.

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

    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.

  17. Ecotoxicological studies with newly hatched larvae of Concholepas concholepas (Mollusca, Gastropoda): bioassay with secondary-treated kraft pulp mill effluents.

    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

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

    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

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

    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.

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

    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

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

    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

  2. The status of the genus Bostryx Troschel, 1847, with description of a new subfamily (Mollusca, Gastropoda, Bulimulidae)

    Abraham Breure

    2012-01-01

    Abstract The status of the genus Bostryx is discussed and, based on morphological and molecular data, restricted to a group of species related to Bostryx solutus , for which the new subfamily name Bostrycinae is introduced.

  3. Putative midkine family protein up-regulation in Patella caerulea (Mollusca, Gastropoda) exposed to sublethal concentrations of cadmium

    A cDNA sequence of a putative midkine (MK) family protein was identified and characterised in the mollusc Patella caerulea. The midkine family consists of two members, midkine and pleiotrophin (PTN), and it is one of the recently discovered cytokines. Our results show that this putative midkine protein is up-regulated in specimens of P. caerulea exposed to sublethal cadmium concentrations (i.e. 0.5 and 1 mg l-1 Cd) over a 10-day exposure period. Semiquantitative RT-PCR and quantitative Real time RT-PCR estimations indicate elevated expression of midkine mRNA in exposed specimens compared to controls. Moreover, RT-PCR Real time values were higher in the viscera (here defined as the part of the soft tissue including digestive gland plus gills) than in the foot (i.e. foot plus head plus heart) of the limpets. At present, information on the functional signalling significance of the midkine family proteins suggests that the up-regulation of P. caerulea putative midkine family protein is a distress signal likely with informative value on health status of the organism and with potential prognostic capability

  4. Histology and Cytochemistry of the Neurosecretory Cells (NSC of the Freshwater Snail Lymnaea luteola (Lamarck Mollusca: Gastropoda

    Vijaya Kumar Kanapala

    2015-01-01

    Full Text Available Four types of neurosecretory (NS cells are noticed in the cerebral, pleural, buccal and pedal ganglion of the freshwater snail Lymnaea luteola. According to the size and staining properties they are classified as A, B, C and D type cells. These are giant cells, medium cells, small cells and smallest cells. Type ‘A’ cells are largest of the all cells and measures about 0.0600-0.0800 mm in diameter. The B cells are smaller than ‘A’ cells and are ranges from 0.035-0.040 mm in diameter. The ‘C’ and ‘D’ cells are smaller than the ‘A’ and ‘B ‘cells and more or less oval in shape. The histochemical observations reveal that the neurosecretory material is rich in carbohydrates, disulphides, sulfhydryl group, protein bound amino groups, glycoprotein and lipids.

  5. Spatial diversity of rocky midlittoral macro-invertebrates associated with the endangered species Patella ferruginea (Mollusca: Gastropoda) of Tunisian coastline

    Tlig-Zouari, Sabiha; Rabaoui, Lotfi; Fguiri, Hosni; Diawara, Moctar; Ben Hassine, Oum Kalthoum

    2010-04-01

    The present study focuses on horizontal spatial variability of benthic macrofauna associated with Patella ferruginea. Thirty-six samples collected at 12 transects belonging to 4 midlittoral sites along the rocky Tunisian coastline, were examined. A total of 44 species belonging to 5 taxa were found. Multivariate analysis applied on gathered data did not show a horizontal spatial variability at small scale (between transects), but at large scale, between sites as well as sectors. Thus, three groups of communities were identified (GI: Korbous and El Haouaria; GIIa: Zembra Island and GIIb: Kelibia). The distribution of species abundance within these groups revealed that crustaceans were the most abundant taxon, due to the overwhelming dominance of Chthamalus stellatus. This substratum appeared to create favourable micro-habitats for the installation of molluscs including gastropods. Regarding the low diversity index ( H') and evenness ( J), they seemed to reflect a disturbance and a demographic unbalance within these communities. The heterogeneity of substrate surface, created by C. stellatus specimens appeared to be caused by various complex interactions established between the key components of these communities in particular suspension feeders, predators, herbivorous molluscs and macroalgae. Thus, the dynamic status of each of these communities is the result of these complex interactions.

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

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

  7. Freshwater snails (Mollusca: Gastropoda) from the Commonwealth of Dominica with a discussion of their roles in the transmission of parasites

    We collected six species of freshwater snails from Dominica, including Biomphalaria kuhniana, Gundlachia radiata Helisoma (= Planorbella) trivolvis, Melanoides tuberculata, Neritina punctulata, and Physa marmorata. Our collections indicate that un-reported species such as Gundlachia radiata and Hel...

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

    Nathalie Yonow

    2012-05-01

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

  9. Occurrence of Elysia grandifolia (Mollusca, Gastropoda), and its radionuclide content from Tarapur coastal waters, west coast of India

    Occurrence, morphological features, feeding habits, metal and radionuclide content of an opisthobranch sacoglossan Elysia grandifolia Kelaart have been reported. Mn was highest in E.grandifolia whereas Zn was most abundant in eggs. Radionuclide 131I was most abundant in tissues 1.4 Bq g-1 dry weight and in eggs 0.8 Bq g-1 dry weight. Radionuclide 60Co in eggs was, 1.0 Bq g-1 dry weight and in tissues, 0.08 Bq g-1 dry weight. Possibility of using the species and eggs as indicators for 131I and 60Co radionuclides in the marine environment is discussed. (author). 12 refs., 2 figs

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

    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. PMID:26845705

  11. Relation between aquatic plants and gastropods (Mollusca, Gastropoda) in the region of Gentilly I (Quebec) nuclear generating station

    This study is based on a sampling of the gastropods present in the vegetation of the St. Lawrence riverside zone at Gentilly. A total of 536 plant specimens belonging to 20 species as well as 37 239 specimens grouping 10 different species of gastropods were sampled. A comparison of the plant species - mollusc data was carried out. The analysis of the results indicates that prosobranchs have no affinity whatsoever for any plant species in particular. The pulmonates, however, are found mainly on emergent plants. (author)

  12. Putative midkine family protein up-regulation in Patella caerulea (Mollusca, Gastropoda) exposed to sublethal concentrations of cadmium

    Vanucci, Silvana [Department of Animal Biology and Marine Ecology, University of Messina, Salita Sperone 31, 98166 S Agata, Messina (Italy)]. E-mail: silvana.vanucci@unime.it; Minerdi, Daniela [Department of Animal Biology and Genetics, University of Florence, via Romana 19, 50125 Florence (Italy); Kadomatsu, Kenji [Department of Biochemistry, University of Nagoya Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Mengoni, Alessio [Department of Animal Biology and Genetics, University of Florence, via Romana 19, 50125 Florence (Italy); Bazzicalupo, Marco [Department of Animal Biology and Genetics, University of Florence, via Romana 19, 50125 Florence (Italy)

    2005-11-30

    A cDNA sequence of a putative midkine (MK) family protein was identified and characterised in the mollusc Patella caerulea. The midkine family consists of two members, midkine and pleiotrophin (PTN), and it is one of the recently discovered cytokines. Our results show that this putative midkine protein is up-regulated in specimens of P. caerulea exposed to sublethal cadmium concentrations (i.e. 0.5 and 1 mg l{sup -1} Cd) over a 10-day exposure period. Semiquantitative RT-PCR and quantitative Real time RT-PCR estimations indicate elevated expression of midkine mRNA in exposed specimens compared to controls. Moreover, RT-PCR Real time values were higher in the viscera (here defined as the part of the soft tissue including digestive gland plus gills) than in the foot (i.e. foot plus head plus heart) of the limpets. At present, information on the functional signalling significance of the midkine family proteins suggests that the up-regulation of P. caerulea putative midkine family protein is a distress signal likely with informative value on health status of the organism and with potential prognostic capability.

  13. Recent expansion and relic survival: Phylogeography of the land snail genus Helix (Mollusca, Gastropoda) from south to north Europe.

    Fiorentino, V; Manganelli, G; Giusti, F; Ketmaier, V

    2016-05-01

    Little is known about the evolutionary history of Helix, despite the fact that it includes the largest land snails in the western Palaearctic, some of which (e.g. H. pomatia Linnaeus, 1758) are valuable human food. We compared two groups of Helix with apparently contrasting evolutionary histories: the widespread species H. pomatia and the group distributed along the Italian Apennine chain, a relatively unknown set of species with a restricted distribution over a range of altitudes. To reconstruct the evolutionary trajectories of these two groups, we analysed morphological (shell and genitalia) and molecular characters (mitochondrial and nuclear markers) in a total of 59 populations from northern and central Europe (H. pomatia) and along the Apennine chain (various species). We also reconstructed the phylogeny and the evolutionary history of the genus by combining our data with that currently available in the literature. We found that spatial changes did not merely imply fragmentation of populations, but also implied environmental changes (woodlands vs. grasslands) that may have triggered the observed phenotypic diversification. We also found that Anatolia is the ancestral range of Helix and is therefore an important area for the Palaearctic diversity. The results provide insights into the evolutionary history of species richness and more generally into the processes that may have shaped the distribution and diversification of these organisms across Europe and the peri-Mediterranean area. PMID:26926944

  14. Tandonia rustica (Millet 1843) (Mollusca : Gastropoda), nouvelle espèce de limace pour la Vendée

    Eulin, Jean-Louis

    2013-01-01

    The slug Tandonia rustica has recently been discovered in the forest of Mervent, in Vendée. After a brief description of the site where the gastropod was found, the author describes the biology, ethology and distribution in France of this species.

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

    Abraham S.H. Breure

    2015-01-01

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

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

    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,

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

    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.

  18. Phylogeographic patterns in New Zealand and temperate Australian cantharidines (Mollusca: Gastropoda: Trochidae: Cantharidinae): Trans-Tasman divergences are ancient.

    Donald, Kirsten M; Spencer, Hamish G

    2016-07-01

    Current taxonomic treatments of New Zealand and temperate Australian members of the gastropod subfamily Cantharidinae imply that species on either side of the Tasman Sea are closely related and, in some cases, congeneric. Such a close relationship, however, entails a relatively recent divergence of Australian and New Zealand lineages, which seems inconsistent with what is known about cantharidine larval development in general. In order to address these issues, mitochondrial and nuclear DNA sequences were used to ascertain how cantharidine genera became established over the wide geographical range of temperate Australia and New Zealand, including their subantarctic islands. Our robust and dated phylogenies (based on 16S, COI, 12S and 28S sequences) revealed that Australian and New Zealand species fall into endemic clades that have been separated for, at most, 35million years. This divergence date postdates a vicariant split by around 50million years and we suggest that, once again, long-distance trans-Tasman dispersal has played a pivotal role in molluscan evolution in this part of the world. Our results also show that the current classification requires revision. We recognize three genera (Cantharidus [comprising 2 subgenera: Cantharidus s.str. and Pseudomargarella n. subgen.], Micrelenchus [comprising 2 subgenera: Micrelenchus s.str. and Mawhero] and Roseaplagis n. gen.) for New Zealand cantharidine species. In our dated BEAST tree, these genera form a clade with the endemic Australian Prothalotia and South African Oxystele. Other temperate Australian cantharidines in our study fall into previously recognized genera (Phasianotrochus, Thalotia, Calthalotia), which are all quite distinct from Cantharidus in spite of some authors considering various of them to be possible synonyms. Finally, we remove the Australian genus Cantharidella from the Cantharidinae to the subfamily Trochinae and erect a new genus, Cratidentium n. gen., also in the Trochinae, to accommodate several Australian species previously considered to belong to Cantharidella. PMID:27118181

  19. Radix dolgini: The integrative taxonomic approach supports the species status of a Siberian endemic snail (Mollusca, Gastropoda, Lymnaeidae).

    Vinarski, Maxim V; Aksenova, Olga V; Bespalaya, Yulia V; Bolotov, Ivan N; Schniebs, Katrin; Gofarov, Mikhail Yu; Kondakov, Alexander V

    2016-01-01

    The molecular techniques are the standard tool for the study of the taxonomic position and phylogenetic affinities of the lymnaeid genus Radix Montfort, 1810, and the majority of the European representatives of this taxon have been studied in this respect. However, a plethora of nominal species of Radix described from Northern Asia (Siberia and the Russian Far East) are still characterized only morphologically, raising some doubts concerning their validity. In this paper, we present the triple (morphological, molecular, and zoogeographical) evidence that there is at least one endemic species of Radix, Radix dolgini (Gundrizer and Starobogatov, 1979), widely distributed in Siberia and Western Mongolia. Phylogenetically, it is a sister species to the European R. labiata (Rossmaessler, 1835) [=R. peregra auct.], and their common ancestor most probably lived in the Pliocene, nearly 3.25Myr ago. Our results assume the existence of an extended dispersal barrier for freshwater hydrobionts between Europe and Siberia in the Late Pliocene that may be important for biogeographical explanations. Three other nominal Siberian species of Radix: R. kurejkae (Gundrizer and Starobogatov, 1979), R. gundrizeri (Kruglov and Starobogatov, 1983), and R. ulaganica (Kruglov and Starobogatov, 1983) proved to be the junior synonyms of R. dolgini. PMID:26705968

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

    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.

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

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

    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

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

    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

  4. DIVERSITAS DAN KERAPATAN MANGROVE, GASTROPODA DAN BIVALVIA DI ESTUARI PERANCAK, BALI

    Susiana; Ali, Syamsu Alam; Rukminasari, Nita

    2011-01-01

    Penelitian ini bertujuan membandingkan diversitas dan kerapatan mangrove dengan kepadatan gastropoda dan bivalvia di mangrove alami dan rehabilitasi. Pengukuran ekosistem mangrove menggunakan transek kuadrat 10 m x 10 m. Kelimpahan dan kepadatan gastropoda dan bialvia menggunakan transek kuadrat berukuran 1 m x 1 m. Analisis nMDS, cluster untuk melihat hubungan karekteristik mangrove alami dan rehabilitasi dianalisis secara deskriptif dan analisis regresi untuk mendetermi...

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

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

    1985-01-01

    Bibliography of the freshwater Pearlmussel Margaritifera margaritifera (Linnaeus, 1758) [Mollusca: Pelecypoda] The freshwater pearlmussel, described by Linnaeus as Mya margaritifera is one of the most important molluscs existing. It belongs with only a few congeneric fossil and recent species to the distinct family Margaritiferidae. The distribution of the species is Holarctic (figs. 1-2), being known from western, northern and central Europe, and via Siberia to Japan. In North America it is ...

  6. Corbicula fluminea (Mollusca, Bivalvia) - the new freshwater clam for Slovakia

    Specimens of the expansive Asian freshwater clam Corbicula fluminea O. F. Mueller, 1774 (Mollusca: Bivalvia, Corbiculidae) were found on the following three localities of Danube river of Slovakia: Radvan nad Dunajom env. (DFS - 8276a), Komarno env. (DFS - 8274b), Gabcikovo env. (DFS - 8171a). The basic information about this species, key for determination and a photo of an adult individual are presented on the poster. (authors)

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

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

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

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

  9. Patterns of larval distribution and settlement of Concholepas concholepas (Bruguiere, 1789 (Gastropoda, Muricidae in fjords and channels of southern Chile Patrones de distribución de larvas y asentamiento de Concholepas concholepas (Bruguiere, 1789 (Gastropoda, Muricidae en fiordos y canales del sur de Chile

    CARLOS MOLINET

    2005-09-01

    Full Text Available The distribution of Concholepas concholepas (Mollusca, Gastropoda, Muricidae is limited to the coasts of Chile and southern Peru. Almost all studies of this gastropod have been carried out in open coastal systems, rather than the fjords and channels of southern Chile, despite the fact that this area represents ca. 95 % of the total coastline in this country. Although there is a large volume of background literature on C. concholepas, almost nothing is published about early larval development under natural conditions, mostly because early veligers have rarely been found in nature. This study is the first attempt to determine the spatial and temporal abundance and size patterns of C. concholepas larvae in their natural environment throughout all of their developmental stages until they settle. Weekly plankton samples were obtained at the surface and at 8 m depth in four locations in southern Chile in combination with temperature and salinity records in each location. Settlement was quantified using artificial substrates in all locations. We have observed that C. concholepas larval development occurs throughout the entire year in Chilean inland seas, with early veliger larvae being released mostly from August to March, reaching the competent stage around June to August, and settling between July and August. Thus, larvae appear to have a long planktonic development that can last between 6 and 12 months. Differences in local hydrology could affect larval development of C. concholepas in this region. Further oceanographic and ecological investigation is necessary in order to answer the questions and hypotheses originated from this studyConcholepas concholepas (Mollusca, Gastropoda, Muricidae se distribuye entre las costas del sur de Perú y extremo sur de Chile. Prácticamente todos los estudios sobre este gastrópodo han sido realizados en costas expuestas, sin considerar los fiordos y canales del sur de Chile, a pesar de que estos representan

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

    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

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

    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.

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

    Haszprunar, Gerhard; Wanninger, Andreas Wilhelm Georg

    2008-01-01

    intercrossing. The present results and previous findings, in particular the chitinous, non-moulted cuticle, the sinus circulatory system, and a number of neural features shared by Kamptozoa and Mollusca, provide substantial evidence for a direct sister-group relationship between these phyla. In addition, the...... basal position of the Solenogastres (Neomeniomorpha) within the Mollusca is corroborated....

  13. Megafauna recovered from a cold hydrocarbon seep in the deep Alaskan Beaufort Sea, including a new species of Axinus (Thracidae: Bivalvia: Mollusca)

    Powell, C. L.; Valentich-Scott, P.; Lorenson, T. D.; Edwards, B. D.

    2011-12-01

    Several specimens of a new species of Axinus and a single well-worn gastropod columella provisionally assigned to the genus Neptunea (Buccinidae: Gastropoda: Mollusca) were recently recovered from at least two cores, the longest of which is 5.72 m long, from a large seafloor mound, informally named the Canning Seafloor Mound (CSM). The CSM is located at 2,530 m water depth on the Alaskan Beaufort Sea slope north of Camden Bay and is a fluid explosion feature containing methane hydrate and methane-saturated sediments overlying a folded and faulted deep basin. Only two modern species of Axinus are currently known. Axinus grandis (Verrill & Smith, 1885) is a northern Atlantic species and the recently described species, A. cascadiensis Oliver and Holmes (2007), is only known from Baby Bare Seamount, Cascadia Basin, northeastern Pacific Ocean. Common fragments, single valves, and a single articulated specimen represent this new Axinus species. These shells were distributed over nearly the entire length of the primary core. All specimens show wear and (or) dissolution. The age of these specimens is unknown and no living representatives were encountered. The genus Axinus has a fossil record back to the early Eocene in England and the Paleocene and Eocene in Egypt. Biogeographically the genus appears to have originated in the Tethys Sea and became established in the Atlantic Ocean during the Eocene, spreading across the Arctic Ocean in the late Tertiary. With the opening of the Bering Strait in the latest Miocene or early Pliocene the genus Axinus migrated southwest into the northeast Pacific. Interestingly, hydrocarbon seep deposits are also present on the adjacent North Slope of Alaska in the Marsh Anticline at Carter Creek, Camden Bay. These rocks, the Nuwok beds, contain abundant Thracidae bivalve of the genus Thracia, but not Axinus, however the rocks also represent cold seep deposits. These rocks have been variously dated from Oligocene to Pliocene and the exact age

  14. Amundsen Sea Mollusca from the BIOPEARL II expedition

    Camille Moreau

    2013-04-01

    Full Text Available Information regarding the molluscs in this dataset is based on the epibenthic sledge (EBS samples collected during the cruise BIOPEARL II / JR179 RRS James Clark Ross in the austral summer 2008. A total of 35 epibenthic sledge deployments have been performed at five locations in the Amundsen Sea at Pine Island Bay (PIB and the Amundsen Sea Embayment (ASE at depths ranging from 476 to 3501m. This presents a unique and important collection for the Antarctic benthic biodiversity assessment as the Amundsen Sea remains one of the least known regions in Antarctica. Indeed the work presented in this dataset is based on the first benthic samples collected with an EBS in the Amundsen Sea. However we assume that the data represented are an underestimation of the real fauna present in the Amundsen Sea. In total 9261 specimens belonging to 6 classes 55 families and 97 morphospecies were collected. The pecies richness per station varied between 6 and 43. Gastropoda were most species rich 50 species followed by Bivalvia (37, Aplacophora (5, Scaphopoda (3 and one from each of Polyplacophora and Monoplacophora.

  15. Amundsen Sea Mollusca from the BIOPEARL II expedition.

    Moreau, Camille; Linse, Katrin; Griffiths, Huw; Barnes, David; Kaiser, Stefanie; Glover, Adrian; Sands, Chester; Strugnell, Jan; Enderlein, Peter; Geissler, Paul

    2013-01-01

    Information regarding the molluscs in this dataset is based on the epibenthic sledge (EBS) samples collected during the cruise BIOPEARL II / JR179 RRS James Clark Ross in the austral summer 2008. A total of 35 epibenthic sledge deployments have been performed at five locations in the Amundsen Sea at Pine Island Bay (PIB) and the Amundsen Sea Embayment (ASE) at depths ranging from 476 to 3501m. This presents a unique and important collection for the Antarctic benthic biodiversity assessment as the Amundsen Sea remains one of the least known regions in Antarctica. Indeed the work presented in this dataset is based on the first benthic samples collected with an EBS in the Amundsen Sea. However we assume that the data represented are an underestimation of the real fauna present in the Amundsen Sea. In total 9261 specimens belonging to 6 classes 55 families and 97 morphospecies were collected. The species richness per station varied between 6 and 43. Gastropoda were most species rich 50 species followed by Bivalvia (37), Aplacophora (5), Scaphopoda (3) and one from each of Polyplacophora and Monoplacophora. PMID:23794869

  16. All the three ParaHox genes are present in Nuttallochiton mirandus (Mollusca: polyplacophora): evolutionary considerations.

    Barucca, Marco; Biscotti, Maria A; Olmo, Ettore; Canapa, Adriana

    2006-03-15

    The ParaHox gene cluster contains three homeobox genes, Gsx, Xlox and Cdx and has been demonstrated to be an evolutionary sister of the Hox gene cluster. Among deuterostomes the three genes are found in the majority of taxa, whereas among protostomes they have so far been isolated only in the phylum Sipuncula. We report the partial sequences of all three ParaHox genes in the polyplacophoran Nuttallochiton mirandus, the first species of the phylum Mollusca where all ParaHox genes have been isolated. This finding has phylogenetic implications for the phylum Mollusca and for its relationships with the other lophotrochozoan taxa. PMID:16331637

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

    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...

  18. Los moluscos terrestres (Mollusca: Gastropoda de Costa Rica: clasificación, distribución y conservación

    Zaidett Barrientos Llosa

    2010-12-01

    Full Text Available Los moluscos terrestres son un grupo muy poco estudiado a nivel mundial. Hay 183 especies reportadas para Costa Rica, 30% son endémicas y 7% posiblemente están extintas. Se espera que en el país haya alrededor de 400 especies, de más del 95% se desconoce su biología, ecología, distribución, genética y otros campos de estudio. En Costa Rica las familias con mayor número de especies son Spiraxidae, Orthalicidae y Subulinidae. No obstante, es posible que Euconulidae sea aun más diversa, pues habitan las zonas altas del país que es en donde menos trabajo se ha hecho. El estudio de regiones altas aumentará el porcentaje de endemismo. Los futuros trabajos malacológicos taxonómicos, biológicos y ecológicos deben considerar la poca movilidad de este grupo, su tendencia a formar especies nuevas en simpatría, la especificidad de requerimientos de microhábitat, el hermafroditismo, la alta tasa de evolución (10% por millón de años y la divergencia entre especies (2-30%. Para proteger adecuadamente la biodiversidad de la malacofauna costarricense, se requiere de estudios que determinen la distribución y abundancia de las especies y el efecto del uso de la tierra y del climático.

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

    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.

  20. 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

    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.

  1. 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

    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.

  2. Vector ecology of human schistosomiasis in south India and description of a new species of the genus Ferrissia (Mollusca: Gastropoda: Planorbidae)

    Anbalagan Sankarappan; Balachandran Chellapandian; Arun Prasanna Vimalanathan; Kannan Mani; Dinakaran Sundaram; Krishnan Muthukalingan

    2015-01-01

    Background & objectives: Vector ecology and taxonomy of snails is a prerequisite for controlling schistosomiasis in the tropics. The ecology of the freshwater limpet genus Ferrissia was investigated for detection of cercariae larvae in them, and taxonomic description of a new species of the genus Ferrissia. Methods: This study was conducted in 15 perennial streams from five different hills of south India. To study the seasonal patterns, a stream from each hill was selected and sampled in t...

  3. Vector ecology of human schistosomiasis in south India and description of a new species of the genus Ferrissia (Mollusca: Gastropoda: Planorbidae

    Anbalagan Sankarappan

    2015-01-01

    Interpretation & conclusion: Our results showed the distribution, habitat preference and seasonality of limpets, and recommend the detection of Schistosoma from limpets as well as human samples by use of molecular tools.

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

    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

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

    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

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

    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.

  7. 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.

    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.

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

    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.

  9. New records of Omalonyx matheroni (Pontiez & Michaud, 1835 (Mollusca, Gastropoda, Succineidae for the São Paulo and Paraná States.

    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.

  10. Threatened freshwater and terrestrial molluscs (Mollusca, Gastropoda et Bivalvia of Santa Catarina State, Southern Brazil: check list and evaluation of regional threats

    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.

  11. 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

    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.

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

    Santana Teles Horácio Manuel

    1997-01-01

    Full Text Available A introdução de Achatina fulica é assinalada em Itariri, SP, Brasil. Essa espécie de caramujo terrestre foi importada para cultivo, visando à comercialização para consumo humano como "escargot". O encontro de exemplares em vida livre mostra a dispersão de A. fulica e, conseqüentemente, o risco de transmissão de Angiostrongylus cantonensis, nematóide parasita do homem e de outros vertebrados. Além disso, o caramujo é uma praga importante da agricultura.

  13. Pyramidellidae (Mollusca, Gastropoda, Heterobranchia) collected during the Dutch CANCAP and MAURITANIA expeditions in the south-eastern part of the North Atlantic Ocean (part 2)

    Aartsen, van, B.; Gittenberger, E.; Goud, J.

    2000-01-01

    The species of the Pyramidellidae collected during several expeditions in the south-eastern part of the North Atlantic Ocean are listed, with locality data, depth ranges, and notes on nomenclature, systematics and distribution. The samples classified with the genera Eulimella (partly), Anisocycla, Syrnola, Chrysallida and Odostomella are dealt with in this paper. In total 70 species are reported from the research area, 24 of which are described as new to science. A lectotype of Obeliscus grac...

  14. The heart of a dragon: 3D anatomical reconstruction of the ‘scaly-foot gastropod’ (Mollusca: Gastropoda: Neomphalina) reveals its extraordinary circulatory system

    Chen, Chong; Copley, Jonathan T.; Linse,Katrin; Rogers, Alex D.; Sigwart, Julia D.

    2015-01-01

    Introduction The ‘scaly-foot gastropod’ (Chrysomallon squamiferum Chen et al., 2015) from deep-sea hydrothermal vent ecosystems of the Indian Ocean is an active mobile gastropod occurring in locally high densities, and it is distinctive for the dermal scales covering the exterior surface of its foot. These iron-sulfide coated sclerites, and its nutritional dependence on endosymbiotic bacteria, are both noted as adaptations to the extreme environment in the flow of hydrogen sulfide. We present...

  15. Vertigo moulinsiana (Dupuy 1849) (Mollusca : Gastropoda : Pulmonata) dans le marais des Bourbes à Olonne-sur-Mer en Vendée

    Goyaud, Christian

    2011-01-01

    This note relates the discovery of on species of land snails of the Vendée kind in "marais des Bourbes" (Olonne-sur-Mer) on the Vendée coast. This is the second time Vertigo moulinsiana, a rare species in Vendée, has been found.

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

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

    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.

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

    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.

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

    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

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

    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. PMID:26700239

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

    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.

  2. New Mediterranean Biodiversity Records (June 2012

    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.

  3. New genus and species of polyplacophora (Mollusca) from the East China Sea

    Xu, Fengshan

    1990-12-01

    The present paper dealing with two new species and one new genus of the Polyplacophora, is the first of a series of reports of systematic study on the deep sea mollusca collected by the research vessels JINXING and KEXUE I of the Academia Sinica, Institute of Oceanology, during 1978 and 1981 from the continental margin to the bathyal zone of the East China Sea.

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

    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.

  5. Ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae), hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil

    Francisco José Pegado Abílio; Takako Watanabe

    1998-01-01

    Foi registrada a ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae), primeiro hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil, associado a macrófitas aquáticas.

  6. ДИНАМИКА ПОКАЗАТЕЛЕЙ ЭНЕРГЕТИЧЕСКОГО СТАТУСА ГЕМОЦИТОВ НЕКОТОРЫХ ПРЕДСТАВИТЕЛЕЙ КЛАССА GASTROPODA (MOLLUSCA) В УСЛОВИЯХ ОСМОТИЧЕСКОЙ НАГРУЗКИ

    Кулько, Светлана

    2014-01-01

    В статье рассматриваются особенности энергетических реакций гемоцитов некоторых представителей типа Mollusca в ответ на инкубацию в растворах с различной осмолярностью. Исследование было произведено при помощи конфокального лазерного сканирующего микроскопа, с окраской гемоцитов родамином Б, и позволило доказать, что наибольшими энергетическими затратами обладают большие амебоциты всех изученных видов-представителей....

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

    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

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

    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.

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

    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. 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

    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.

  11. Complexo Littorina ziczac (Gmelin) (Mollusca, Gastropoda, Caenogastropoda) no litoral fluminense: análise morfométrica, distribuição vertical e bioquímica The Littorina ziczac (Gmelin) complex (Mollusca, Gastropoda, Caenogastropoda) in the Rio de Janeiro coast: morphometric analysis, vertical distribution and biochemistry

    Ricardo Silva Absalão; Renata Alves Pinheiro Roberg

    1999-01-01

    The Littorina ziczac (Gmelin, 1791) species complex was studied in Rio de Janeiro State, southeastern Brazil. The occurrence of three species was confirmed, through the analysis of penis morphology: L. ziczac (Gmelin, 1791), L. lineata d'Orbigny, 1841 and L. lineolata d'Orbigny, 1840. There is a correlation between the morphology of the penis and shell shape, thus it was possible to make a discrimination model based in conchologic data, with an efficiency of 75%. However, this model cannot be...

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

    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

  13. Ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae), hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil Occurrence of Lymnaea columella (Gastropoda: Lymnaeidae), first intermediate host of Fasciola hepatica, for the state of Paraíba, Brazil

    Francisco José Pegado Abílio; Takako Watanabe

    1998-01-01

    Foi registrada a ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae), primeiro hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil, associado a macrófitas aquáticas.The occurrence of Lymnaea Columella (Gastropoda: Lymnaeidae), first intermediate host of Fasciola hepatica, is recorded for the first time in the state of Paraíba, Brazil, associeted with aquatic macrophytes.

  14. Biogeographic and species richness patterns of Gastropoda on the southwestern Atlantic

    FLOETER S. R.

    1999-01-01

    Full Text Available Patterns of richness and biogeography of Gastropoda molluscs were determined based on lists of species from five sites along the southwestern Atlantic. The analysis of the distribution patterns of these sites confirmed the existence of a broader transition zone between southern Espírito Santo State (21°S and Rio Grande do Sul State (32°S. This zone is very heterogeneous, presenting a low endemism rate and a significant number of species common to the near provinces, and does not show enough consistency to be considered as an independent biogeographic province as proposed by Palacio (1980. Observing the distribution of species along the southwestern Atlantic we find an increase in the proportion of species with greatest latitudinal ranges (occurring from the tropics to Patagonia from lowest to highest latitudes, following Rappoport's rule.

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

    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.

  16. 76 FR 56607 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List 42 Great...

    2011-09-13

    ... States (August 18, 2009; 74 FR 41649); thus, these three species are not included in this finding. In the... from the phylum Mollusca, class Gastropoda, superorder Caenogastropoda (Bouchet and Rocroi 2005, pp....

  17. LISTA DE LOS MOLUSCOS (GASTROPODA-BIVALVIA) DULCEACUÍCOLAS Y ESTUARINOS DE LA CUENCA DEL ORINOCO (VENEZUELA)

    Lasso, Carlos A.; Martínez-Escarbassiere, Rafael; Capelo, Juan Carlos; Morales-Betancourt, Mónica A.; Sánchez-Maya, Alejandro

    2009-01-01

    Se realizó una revisión bibliográfica y de colecciones en museos, así como de datos originales de los autores, para reconocer las especies dulceacuícolas y estuarinas de moluscos gastrópodos y bivalvos presentes en la cuenca del Orinoco (Venezuela). Se consolida un listado preliminar para la cuenca de 104 especies distribuidas entre la clase Gastropoda (14 familias y 58 especies) y la clase Bivalvia (13 familias y 45 especies). Entre los gastrópodos la familia Ampullaridae fue la más diversa ...

  18. [Diversity and microstructure of quitons (Mollusca: Polyplacophora) from the Caribbean of Costa Rica].

    García-Ríos, Cedar I; Alvarez-Ruiz, Migdalia

    2011-03-01

    Diversity and microstructure of quitons (Mollusca: Polyplacophora) from the Caribbean of Costa Rica. The polyplacophorans of the coral reef on the Caribbean coast of Costa Rica have been insufficiently studied. The examination of coral rubble accumulated in the shallow sublitoral waters on four collection stations in Provincia Limón revealed a higher diversity of chitons than was documented. From the country eight species were previously known: Ischnochiton erythronotus (C.B. Adams 1845); Ischnoplax pectinata (Sowerby 1840); Stenoplax boogii (Haddon 1886); S. purpurascens (C.B. Adams 1845); Acanthopleura granulata (Gmelin 1791); Chiton marmoratus Gmelin 1791; C. tuberculatus Linnaeus 1758 and Acanthochitona rhodea (Pilsbry 1893). This study added five more species that are reported here for the first time: Callistochiton portobelensis Ferreira 1976; Ischnochiton kaasi Ferreira 1987; I. pseudovirgatus Kaas 1972; Acanthochitona balesae Abbott 1954 and Cryptoconchus floridanus (Dall 1889). PMID:21516641

  19. Korttermynbedreigings vir varswater-Mollusca in die Olifantsrivier en enkele sytakke

    Kenné N. de Kock

    2013-06-01

    Full Text Available Die bewaringstatus van minder as 2% van die ongeveer 7000 molluskspesies bekend wêreldwyd, is tot dusver behoorlik geassesseer. Gevolglik is die algemene vlak van bedreiging vir molluske power gedokumenteer en hoogs waarskynlik onderskat. Varswatermolluske is permanente waterbewoners wat oor beperkte voortbewegingsvermoë beskik en aan ’n verskeidenheid van antropogeniese afvalstowwe blootgestel word omdat waterbronne dikwels as stortplek vir ’n groot verskeidenheid van nadelige besoedelstowwe gebruik word. Die Olifantsrivier word dikwels as een van die mees getransformeerde riviere in Suider-Afrika beskryf en word toenemend aan uitermate hoë druk onderwerp betreffende natuurlike hulpbronne en die geassosieerde landelike versteurings, asook besoedeling. Omdat min inligting oor die diversiteit van Mollusca in die Olifantsrivier op rekord is, is in die huidige studie vier opnames tydens twee opeenvolgende jare gemaak van die molluske in die Olifantsrivier en geselekteerde sytakke by onderskeidelik drie lokaliteite op die Hoëveld en vier in die Laeveld. Die pH en elektriese geleidingsvermoë van die water is by elk van die lokaliteite bepaal en het gewissel tussen 6.93 en 9.50, en 110 µS en 1336 µS, vir pH en geleidingsvermoë onderskeidelik. ’n Totaal van 25 molluskspesies is tydens die vier opnames versamel wat die eksotiese indringerspesies Lymnaea columella, Physa acuta, Aplexa marmorata en Tarebia granifera insluit. Laasgenoemde spesie het verreweg die grootste getal eksemplare in totaal opgelewer, hoofsaaklik by ’n lokaliteit wat as grootliks getransformeerd beskryf kan word. Die resultate van hierdie ondersoek kan as basis vir toekomstige opnames dien om die impak van antropogeniese versteurings op die diversiteit van die Mollusca in die Olifantsrivier- en opvanggebied te evalueer.Short-term threats for the sustained survival of freshwater Mollusca in the Olifants River and selected tributaries. The conservation status of less

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

    Juan Francisco Araya; Ricardo Catalán

    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 recor...

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

    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

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

    Ghiglione, Claudio; Alvaro, Maria Chiara; Griffiths, Huw J; Linse, Katrin; Schiaparelli, Stefano

    2013-01-01

    Information regarding the molluscs in this dataset is based on the Rauschert dredge samples collected during the Latitudinal Gradient Program (LGP) on board the R/V "Italica" in the Ross Sea (Antarctica) in the austral summer 2004. A total of 18 epibenthic dredge deployments/samplings have been performed at four different locations at depths ranging from 84 to 515m by using a Rauschert dredge with a mesh size of 500μm. In total 8,359 specimens have been collected belonging to a total of 161 species. Considering this dataset in terms of occurrences, it corresponds to 505 discrete distributional records (incidence data). Of these, in order of abundance, 5,965 specimens were Gastropoda (accounting for 113 species), 1,323 were Bivalvia (accounting for 36 species), 949 were Aplacophora (accounting for 7 species), 74 specimens were Scaphopoda (3 species), 38 were Monoplacophora (1 species) and, finally, 10 specimens were Polyplacophora (1 species). This data set represents the first large-scale survey of benthic micro-molluscs for the area and provides important information about the distribution of several species, which have been seldom or never recorded before in the Ross Sea. All vouchers are permanently stored at the Italian National Antarctic Museum (MNA), Section of Genoa, enabling future comparison and crosschecking. This material is also currently under study, from a molecular point of view, by the barcoding project "BAMBi" (PNRA 2010/A1.10). PMID:24146597

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

    Claudio Ghiglione

    2013-10-01

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

  4. 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.

    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

  5. 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

    Bruno S. Sant'Anna

    2005-11-01

    Full Text Available 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 contact with sea water kills them, and their shells then become available to the hermit crabsEl cangrejo ermitaño depende de conchas de moluscos para hacer de ella su casa. Este estudio ha descubierto una manera inusual de como vive este cangrejo, que generalmente habita la concha de gastrópodos marinos. El estudio fue realizado en la estación marítima de São Vicente, provincia de São Paulo, de mayo de 2001 hasta abril de 2003. Durante ese periodo, un total de 21 cangrejos Clibanarius vittatus (Bosc, 1802 fueron encontrados viviendo en las conchas del caracol terrestre Achatina fulica Bowdich, 1822. A. fulica ocurre en áreas de césped cercanos a la costa, donde el contacto ocasional con el agua de mar provoca su muerte y sus conchas quedan disponibles para el cangrejo ermitaño

  6. 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

    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...

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

    Silva-Souza Ângela Teresa

    2002-01-01

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

  8. The histopathology of the infection of Tilapia rendalli and Hypostomus regani (Osteichthyes) by lasidium larvae of Anodontites trapesialis (Mollusca, Bivalvia).

    Silva-Souza, Angela Teresa; Eiras, Jorge C

    2002-04-01

    It is described the histopathology of the infection of Tilapia rendalli (Osteichthyes, Perciformes, Cichlidae) and Hypostomus regani (Osteichthyes, Siluriformes, Loricariidae) by lasidium larvae of Anodontites trapesialis (Mollusca, Bivalvia, Mycetopodidae). The larvae were encysted within the epidermis of the host, being surrounded by a thin hyaline membrane, 3-6 microm thick, of parasite origin. A proliferative host cell reaction did not occur. The histopathology of the infection shows that the lesions induced by the parasites are minimal. However, the numerous small lesions produced by the release of the larvae may provide optimal conditions for the infection by opportunistic pathogens, namely fungus, which may eventually cause the death of the host. PMID:12048579

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

    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.

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

    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

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

    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.

  12. Predação e foresia (ocasional?) entre imaturos de Simuliidae (Diptera: Culicomorpha) e Asolene (Pomella) Megastoma (Sowerby, 1825) (Mollusca: Gastropoda: Ampullaridae) Predation and phoretic association (occasional?) among immature stages of Simuliidae (Diptera: Culicomorpha) and Asolene (Pomella) megastoma (Sowerby, 1825) (Mollusca: Ampullaridae)

    Sandra Magni Darwich; Victor Py-Daniel; Lúcia Beatriz Lopes Ferreira Mardini

    1989-01-01

    The predation and phoretic association (occasional?) among simulids and mollusks are being registered here for the first time on the Neotropical region. These inter-relations observations were obtained among Asolene (Pomella) megastoma (Sowerby, 1825) and the simulids: Simulium (Thyrsopelma) Orbitale Lutz, 1910; Simulium (Psaroniocompsa) spp. The material studied is proceeding from the Uruguai river Hidrological Basin. Based on the mollusks natural habitat, it is here suggested his use as a p...

  13. Predação e foresia (ocasional? entre imaturos de Simuliidae (Diptera: Culicomorpha e Asolene (Pomella Megastoma (Sowerby, 1825 (Mollusca: Gastropoda: Ampullaridae Predation and phoretic association (occasional? among immature stages of Simuliidae (Diptera: Culicomorpha and Asolene (Pomella megastoma (Sowerby, 1825 (Mollusca: Ampullaridae

    Sandra Magni Darwich

    1989-01-01

    Full Text Available The predation and phoretic association (occasional? among simulids and mollusks are being registered here for the first time on the Neotropical region. These inter-relations observations were obtained among Asolene (Pomella megastoma (Sowerby, 1825 and the simulids: Simulium (Thyrsopelma Orbitale Lutz, 1910; Simulium (Psaroniocompsa spp. The material studied is proceeding from the Uruguai river Hidrological Basin. Based on the mollusks natural habitat, it is here suggested his use as a possible integrated management element for simulids species which immature stages live on mighty river with rocks.

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

    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

  15. Unionid bivalves (Mollusca: Bivalvia: Unionidae) of Presque Isle Bay, Erie, Pennsylvania

    Masteller, E.C.; Maleski, K.R.; Schloesser, D.W.

    1993-01-01

    The purpose of this study was to determine species composition and relative abundance of unionid bivalves (Mollusca: Bivalvia: Unionidae) in Presque Isle Bay, Erie, Pennsylvania 1990-1992. This information was compared with data from the only other extensive survey of unionids in the bay conducted in 1909-1911 (Ortmann 1919) to assess changes over the 80 years preceding the present study. A total of 1,540 individuals representing 18 species were collected in 1990-1992. Five relatively common species (between 7 and 42% of total individuals), six uncommon species (2 and 6%), and seven rare species (<1%) were found. The rare species were Anodontoides ferussacianus, Lasmigona costata, Ligumia recta, Ptychobranchus fasciolaris, Quadrula pustulosa pustulosa, Strophitus undaulatus, and Truncilla donaciformis. Five of the species found in Presque Isle Bay (Leptodea fragilis, Ligumia nasuta, Potamilus alatus, Quadrula quadrula, and Truncilla donaciformis) are listed as critically imperiled and one species (Truncilla truncata) as extirpated in the State of Pennsylvania by the Western Pennsylvania Conservancy. Comparisons between unionid populations in 1909-1911 and 1990-1992 indicate few substantial changes occurred during the past 80 years. A total of 22 species were found; 21 in 1909-1911 and 18 in 1990-1992. Seventeen species were found in both studies, an additional four in 1909-1911 and one in 1990-1992. The relative abundance of 11 of the 17 species found in both studies remained stable (i.e., common or uncommon) over the past 80 years. Only four species listed as uncommon in 1909-1911 were listed as rare in 1990-1992. However, the invasion of the zebra mussel (Dreissena polymorpha) is considered a threat to the continued existence of the entire Unionidae fauna in Presque Isle Bay, a unique habitat of the Great Lakes.

  16. Nacre and false nacre (foliated aragonite) in extant monoplacophorans (=Tryblidiida: Mollusca)

    Checa, Antonio G.; Ramírez-Rico, Joaquín; González-Segura, Alicia; Sánchez-Navas, Antonio

    2009-01-01

    Extant monoplacophorans (Tryblidiida, Mollusca) have traditionally been reported as having an internal nacreous layer, thus representing the ancestral molluscan condition. The examination of this layer in three species of Neopilinidae ( Rokopella euglypta, Veleropilina zografi, and Micropilina arntzi) reveals that only V. zografi secretes an internal layer of true nacre, which occupies only part of the internal shell surface. The rest of the internal surface of V. zografi and the whole internal surfaces of the other two species examined are covered by a material consisting of lath-like, instead of brick-like, crystals, which are arranged into lamellae. In all cases examined, the crystallographic c-axis in this lamellar material is perpendicular to the surface of laths and the a-axis is parallel to their long dimension. The differences between taxa relate to the frequency of twins, which is much higher in Micropilina. In general, the material is well ordered, particularly towards the margin, where lamellae pile up at a small step size, which is most likely due to processes of crystal competition. Given its morphological resemblance to the foliated calcite of bivalves, we propose the name foliated aragonite for this previously undescribed biomaterial secreted by monoplacophorans. We conclude that the foliated aragonite probably lacks preformed interlamellar membranes and is therefore not a variant of nacre. A review of the existing literature reveals that previous reports of nacre in the group were instead of the aragonitic foliated layer and that our report of nacre in V. zografi is the first undisputed evidence of nacre in monoplacophorans. From the evolutionary viewpoint, the foliated aragonite could easily have been derived from nacre. Assuming that nacre represents the ancestral condition, as in other molluscan classes, it has been replaced by foliated aragonite along the tryblidiidan lineage, although the fossil record does not presently provide evidence as to

  17. pH-dependent stability of EGX, a multi-functional cellulase from mollusca, Ampullaria crossean.

    Li, Wen-Ying; Wang, Ji; Li, Yan-Hong; Ding, Ming; Xu, Gen-Jun; Liu, Lan-Ying; Zhao, Fu-Kun

    2004-09-01

    The cellulase activity and stability of EGX, a multi-functional cellulase previously purified from the mollusca Ampullaria crossean, was systematically studied under different pH. The pH induced con-formation and stability change of EGX have been investigated by using the intrinsic fluorescence, ANS fluorescence and CD spectrum. It has been found that the conformation and activity of this cellulase were strongly dependent on the pH. EGX was stable for both the enzyme activity and the conformation from pH 5.6 to pH 7.4. As shown by intrinsic and ANS fluorescence, no red shift of emission maximum occurred and a negligible intensity change was observed at pH 5.6-7.4. The activity of EGX remained about 80% in pH 5.6-7.4 and obviously decreased out of side the pH range. Urea-induced changes in EGX at pH 5.4 and pH 8.0 were measured by intrinsic fluorescence and CD spectrum. At pH 5.4, a significantly red shift of emission maximum occurred when the concentration of urea was 5 M compared to the concentration was 3 M at pH 8.0. The alpha-helix at pH 5.4 was 40.51% in the absence of urea and 31.04% in the presence of 4 M urea. At pH 8.0 the alpha-helix was 7.23% in the presence of 4 M urea. The data indicated that EGX was much susceptible to urea-induced unfolding at pH 8.0 and much stable at pH 5.4. The greater pH dependent stability of EGX may allow the enzyme to adequately catalyze the hydrolysis of cellulosic materials under natural or industrial extreme conditions. PMID:15346197

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

    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

  19. The complete sequence of the mitochondrial genome of Nautilus macromphalus (Mollusca: Cephalopoda

    Boore Jeffrey L

    2006-07-01

    Full Text Available Abstract Background Mitochondria contain small genomes that are physically separate from those of nuclei. Their comparison serves as a model system for understanding the processes of genome evolution. Although complete mitochondrial genome sequences have been reported for more than 600 animals, the taxonomic sampling is highly biased toward vertebrates and arthropods, leaving much of the diversity yet uncharacterized. Results The mitochondrial genome of the bellybutton nautilus, Nautilus macromphalus, a cephalopod mollusk, is 16,258 nts in length and 59.5% A+T, both values that are typical of animal mitochondrial genomes. It contains the 37 genes that are almost universally found in animal mtDNAs, with 15 on one DNA strand and 22 on the other. The arrangement of these genes can be derived from that of the distantly related Katharina tunicata (Mollusca: Polyplacophora by a switch in position of two large blocks of genes and transpositions of four tRNA genes. There is strong skew in the distribution of nucleotides between the two strands, and analysis of this yields insight into modes of transcription and replication. There is an unusual number of non-coding regions and their function, if any, is not known; however, several of these demark abrupt shifts in nucleotide skew, and there are several identical sequence elements at these junctions, suggesting that they may play roles in transcription and/or replication. One of the non-coding regions contains multiple repeats of a tRNA-like sequence. Some of the tRNA genes appear to overlap on the same strand, but this could be resolved if the polycistron were cleaved at the beginning of the downstream gene, followed by polyadenylation of the product of the upstream gene to form a fully paired structure. Conclusion Nautilus macromphalus mtDNA contains an expected gene content that has experienced few rearrangements since the evolutionary split between cephalopods and polyplacophorans. It contains an

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

    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…

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

    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

  2. A associação entre Crepidula aculeata (Gastropoda, Calyptraeidae) a alga calcárea Amphiroa beauvoisii, na Baía de Santos, São Paulo, Brasil

    Setuko Masunari

    1988-01-01

    Association Crepidula aculeata - Amphiroa beauvoisii. Population study of Crepidula aculeata Gmelin, 1791) (Gastropoda Calyptraeidae) and analysis of protocooperative association between the mollusc and the alga were carried out in the phytal of calcareous alga Amphiroa beauvoisii Lamouroux, 1816 at Ilha das Palmas, Santos Bay (24º00'S - 46º19'W). Samples were collected at three sites of different degree of water movement in the intertidal zone and sublittoral fringe during 1975 and 1976. Fro...

  3. The influence of fish cage culture on δ13C and δ15N of filter-feeding Bivalvia (Mollusca)

    The objective of this study was to evaluate the effect of Oreochromis niloticus cage culture promoted variations in the δ13C and δ15N 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 (δ13C) and nitrogen (δ15N) isotopic value analysis in a mass spectrometer. There were significant differences in the δ13C and δ15N values of the invertebrate C. fluminea between the beginning and the end of the experiment. There were no differences between the δ13C and δ15N 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)

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

    Juan Francisco Araya

    2014-04-01

    Full Text Available 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.

  5. Thermal dependency of shell growth, microstructure, and stable isotopes in laboratory-reared Scapharca broughtonii (Mollusca: Bivalvia)

    Nishida, Kozue; Suzuki, Atsushi; Isono, Ryosuke; Hayashi, Masahiro; Watanabe, Yusuke; Yamamoto, Yuzo; Irie, Takahiro; Nojiri, Yukihiro; Mori, Chiharu; Sato, Mizuho; Sato, Kei; Sasaki, Takenori

    2015-07-01

    We experimentally examined the growth, microstructure, and chemistry of shells of the bloody clam, Scapharca broughtonii (Mollusca: Bivalvia), reared at five temperatures (13, 17, 21, 25, and 29°C) with a constant pCO2 condition (˜450 μatm). In this species, the exterior side of the shell is characterized by a composite prismatic structure; on the interior side, it has a crossed lamellar structure on the interior surface. We previously found a negative correlation between temperature and the relative thickness of the composite prismatic structure in field-collected specimens. In the reared specimens, the relationship curve between temperature and the growth increment of the composite prismatic structure was humped shaped, with a maximum at 17°C, which was compatible with the results obtained in the field-collected specimens. In contrast, the thickness of the crossed lamellar structure was constant over the temperature range tested. These results suggest that the composite prismatic structure principally accounts for the thermal dependency of shell growth, and this inference was supported by the finding that shell growth rates were significantly correlated with the thickness of the composite prismatic structure. We also found a negative relationship between the rearing temperature and δ18O of the shell margin, in close quantitative agreement with previous reports. The findings presented here will contribute to the improved age determination of fossil and recent clams based on seasonal microstructural records.

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

    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.

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

    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.

  8. Verspreiding van Burnupia capensis (Walker, 1912 en Burnupia stenochorias (Melvill & Ponsonby, 1903 (Gastropoda: Ancylidae in Suid-Afrika

    Kenné de Kock

    2009-09-01

    Full Text Available Die voorkoms van verteenwoordigers van die Ancylidae in Suid-Afrika is reeds in 1848 gerapporteer. Die eerste omvattende studie van hierdie familie in Suid-Afrika is egter eers in 1923 gepubliseer. Alhoewel verskeie bydraes sedertdien gepubliseer is, is verskeie outeurs van mening dat bestaande kennis oor die Ancylidae steeds gebrekkig is en dat hersiening nie net op spesievlak nie maar ook op genus-vlak nodig is. Tans is daar 14 Burnupia spesies op rekord in die databasis van die Nasionale Varswaterslakversameling (NVWSV. Hierdie bydrae handel oor die geografi ese verspreiding en habitats van B. capensis en B. stenochorias die twee Ancylidae spesies waarvan die meeste versamelpunte in die databasis van die NVWSV op rekord is en wat ook die mees wydverspreide geografi ese verspreiding van hierdie familie vertoon. Alhoewel beide spesies in die meerderheid van die verskeidenheid van waterliggame wat in die databasis vermeld word, aangetref is, is die grootste getal monsters van albei in standhoudende riviere en spruite en op ’n klipperige substraat versamel. Albei spesies is nie gerapporteer uit die droër streke van Suid-Afrika nie waarskynlik as gevolg van ’n beperkte vermoë om desikkasie te kan oorleef in gebiede waar standhoudende habitats ’n uitsondering is. Resultate dui daarop dat hoogte bo seevlak en aard van die substraat ’n belangrike rol gespeel het in die daarstelling van hul gedokumenteerde geografi ese verspreiding soos weerspieël deur die rekords in die NVWSV. Min is oor die bewaringstatus van die Ancylidae van Suid-Afrika bekend, maar die karige inligting wat wel tot ons beskikking is, dui op rede tot kommer. Om sinvolle uitsprake oor die bewaringstatus en spesiediversiteit van die Mollusca van Suid-Afrika te kan maak, word aanbeveel dat van die versamelpunte op rekord weer besoek behoort te word waarna die resultate met die bestaande rekords in die databasis van die NVWSV vergelyk kan word.

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

    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.

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

    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...

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

    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

  12. TOXICITY TESTS WITH EMBRYOS OF MUSSEL Perna perna: EVALUATION OF SPAWNING AND SENSIBILITY TESTES DE TOXICIDADE COM EMBRIÕES DE Perna perna (LINNAEUS, 1758) (MOLLUSCA: MYTILIDAE): AVALIAÇÕES DE INDUÇÃO E SENSIBILIDADE

    R. W. REIS Fo.; C. RESGALLA Jr.

    2002-01-01

    The main goal of this paper was to set up guidelines to standartize the procedure of developing embrio-larval toxicity tests using the native Brazilian mussel Perna perna (Mollusca: Mytilidae). In vitro spawning tests were carried out using adult organisms in order to obtain healthy gametes. Embryos development response caused by variation of temperature, salinity and incubation time was investigated in order to determine the end point and ideal parameter settings to develop toxicity assays. ...

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

    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…

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

    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.

  15. Cargols terrestres (Gastropoda, Stylommatophora del Parc Natural de la Muntanya de Montserrat (Barcelona, NE península ibèrica

    Bros, V.

    2006-11-01

    Full Text Available Land snails (Gastropoda, Stylommatophora in the Natural Park of Montserrat (Barcelona, NE Iberian peninsula The inventory of 73 land snails in the Natural Park of Montserrat was updated following the review of 130 publications. Planned field study was also conducted in areas of different habitats on the Montserrat mountain to provide a preliminary description of the communities of land snails in the study area. A total of 342 samples of land snails were studied and 50 species were identified. The most frequent were Pomatias elegans, Helicigona lapicida, Pseudotachea splendida, Abida polyodon and Otala punctata. In this region of the prelittoral Catalan mountain range, the level of endemism was high for Abida secale bofilli, Montserratina bofilliana and Xerocrassa montserratensis.The results of the field work extend the faunistic catalogue of the Natural Park of Montserrat to include references to Hygromia cinctella, Microxeromagna lowei, Paralaoma servilis and Punctum pygmaeum in the area. Finally, investigation and conservation programmes are suggested for the endemic species Xerocrassa montserratensis, protected by the Plan for Areas of Natural Interest (PEIN approved by Decree 328/1992.

  16. An integrative taxonomic investigation of the diversity of digenean parasites infecting the intertidal snail Austrolittorina unifasciata Gray, 1826 (Gastropoda: Littorinidae) in Australia.

    O'Dwyer, Katie; Faltýnková, Anna; Georgieva, Simona; Kostadinova, Aneta

    2015-06-01

    We investigated for the first time the digenean parasites of Austrolittorina unifasciata Gray (Gastropoda: Littorinidae), a periwinkle snail inhabiting the rocky shores of Australia. Here we present detailed morphological descriptions and molecular data (sequences for the mitochondrial cox1 and the nuclear 28S rRNA gene) for the cercariae and intramolluscan stages of the digenean parasites found. Five species, one each of the families Notocotylidae Lühe, 1909, Gorgocephalidae Manter, 1966 and Philophthalmidae Looss, 1899, and two of the family Renicolidae Dollfus, 1939, were recorded and characterised molecularly. Phylogenetic analyses at the superfamily level provided evidence for the familial and generic affiliation of the species and their relationships with congeners. This study is the first to provide data on the life cycle of a species of the family Gorgocephalidae, a parasite of kyphosid fish for which only adult stages had, thus far, been described. The relatively high prevalence of this species allowed mapping of the cox1 haplotype distribution of Gorgocephalus sp. Aus along the southern coast of New South Wales. PMID:25866083

  17. 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

    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.

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

    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)

  19. Análise comparativa do conteúdo Filo Mollusca em livro didático e apostilas do ensino médio de Cascavel, Paraná Comparative analysis of the Phylum Mollusca contents in a high school instructional book and in teacher's notes/handouts at Cascavel, Paraná, Brazil

    Juliana Cristina dos Santos

    2007-12-01

    Full Text Available O objetivo deste trabalho foi realizar uma análise comparativa entre um livro didático de Biologia utilizado na terceira série do Ensino Médio, da rede estadual de ensino do município de Cascavel, PR, e apostilas utilizadas por duas escolas da rede privada. Após o levantamento e escolha, os materiais didáticos foram submetidos a uma análise geral em relação à capa, encadernação, espaçamento entre linhas, tamanho da letra, ilustrações, quadros e tabelas, e, também, a uma análise específica do conteúdo Filo Mollusca, considerando-se conceitos; sugestões de leituras complementares; erros ortográficos e conceituais; erros de impressão e revisão; ilustrações. Verificou-se que todos os materiais didáticos analisados apresentam falhas. No entanto, em umas das apostilas, foram encontradas mais falhas, pois além do seu conteúdo ser extremamente sucinto e não apresentar um planejamento em relação às atividades propostas, continha imagens incorretas e sem legendas auto-explicativas.The objective of this work was to carry out a comparative analysis between an instructional Biology book used in the junior year of high school in the school network system of the State of Paraná at the municipality of Cascavel, PR, and teacher's notes/handouts used by two schools in the private school network. After surveying and selecting the materials, these were submitted to a general analysis with regard to their cover, binding, line spacing, font size, illustrations, charts and tables, and also to a specific analysis in relation to their Phylum Mollusca contents, in which concepts, supplementary reading suggestions, typos and conceptual errors, printing and proofreading errors, and illustrations were taken into consideration. It was observed that all learning materials analyzed showed imperfections; however, a higher number of imperfections was found in one set of teacher's notes, because besides having an extremely succinct content and

  20. Cirripedios en la dieta del molusco herbívoro Chiton granosus Frembly, 1827 (Mollusca, Placophora presente en el intermareal rocoso de Iquique, norte de Chile Barnacles in the diet of the molluscan grazer Chiton granosus Frembly, 1827 (Mollusca, Placophora present on the intertidal rocky shore of Iquique, northern Chile

    Moisés A Aguilera

    2005-05-01

    Full Text Available Se entrega información preliminar cuantitativa, sobre la presencia de cirripedios en estados de larvas cypris y estados post-metamórficos en la dieta del molusco Chiton granosus Frembly, 1827 (Mollusca, Placophora recolectado en Iquique, Chile. En diciembre de 2000, se observó la presencia de larvas cypris y post-metamórfico con una importante abundancia relativa porcentual (N = 30, 54,1 y 39,9%, respectivamente y con una frecuencia de ocurrencia del 100% en el total de estómagos. Además, se registró una alta frecuencia de larvas cypris (F% = 67 en la porción final del intestino, de éstas 15 presentaron signos de actividad vital (movimiento de apéndices en el 45% del total de estómagos analizados. La ingesta de cirripedios en estados cypris y post-metamórficos, fue observada también con una alta frecuencia durante cinco meses de estudio (N = 10, 96% ± 6,5 y 78% ± 23,6Preliminary quantitative information is given on the presence of barnacle cyprids and post-metamorphic stages in the diet of the molluscan grazer Chiton granosus Frembly 1827 (Mollusca: Placophora sampled at Iquique, Chile. In December 2000, we observed the presence of barnacle cyprids and post-metamorphic stages at a high relative percentage of abundance (N = 30, 54,1% and 39,9%, respectively and they were frequent in all of the individuals analyzed. Moreover, a high frequency of ocurrence of cyprid larvae (F% = 67 was recorded in the distal portion of the intestine; of these larvae, 15 were observed with signs of vital activity (appendage movement in 45% of all the stomachs analyzed. Ingestion of barnacle cyprids and post-metamorphic stages was observed at a high frequency throughout the five months of the study (N = 10, 96% ± 6,5 and 78% ± 23,6

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

    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

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

    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

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

    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

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

    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

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

    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.

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

    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...

  7. Effects of CO-60 gamma radiation on the embryonary development of Biomphalaria Glabrata (Say, 1818)

    Some aspects of the effects of the ionizing radiation on the embryo and on the genetical material of Biomphalaria glabrata (Mollusca: Gastropoda) are presented. The embryos weresubmitted at various stages of development to doses of 5,10,15,20 and 25 Gy of Co-60 gamma radiation. As a criteia of evaluation of the embryos radiosensitivity, four biological parameters were used: mortality, malformation, hatching and chromossomal aberrations. (M.A.C.)

  8. Salida de campo por Valladolid el 2 de abril de 1953

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo por Valladolid capital el 2 de abril de 1953, de la que se anotaron observaciones sobre gasterópodos (Mollusca: Gastropoda), los órdenes Coleoptera e Hymenoptera de insectos (Arthropoda: Hexapoda: Insecta), hallados en estómagos de las siguientes aves: Burhinus oedicnemus (Alcaraván común), Lanius meridionalis (Alcaudón real, llamado L.excubitor por el autor), Milvus migrans (Milano negro) y Milvus milvus (Milano real).

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

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

  10. 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

    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

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

    Carlo Magenta Cunha

    2011-01-01

    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.

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

    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.

  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)

    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

    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. Salida de campo a la finca de Bárbara (Valladolid) el 17 de agosto de 1952

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a la finca de Bárbara (seguramente, en las cercanías de Valladolid capital) el 17 de agosto de 1952, de la que se realizaron observaciones sobre el caracol Helix sp. (Gastropoda, Mollusca), el roedor "Pytimis" (llamado así por el autor, siendo posiblemente el actual género Midrotus), los siguientes reptiles: Natrix maura (Culebra viperina, llamada Tropidonotus viperinus por el autor) y Rhinechis scalaris (Culebra de escalera, llamada Elaphe scalaris por el autor) y las siguie...

  16. Ultrastructural studies of Biomphalaria glabrata (Say, 1818) embryo

    Ultrastructural studies of Biomphalaria glabrata embryos (MOllusca: Gastropoda), and important snail vector of schistosomiasis has not been explored. In the present work it was evaluated a suitable electron microscopical technique for embryos processing. Promising results was obtained with double fixation in 1% glutaraldehyde plus 1% osmium tetroxide in 0.05 M cacodylate buffer (pH 7.4), preliminary staining overnight in 1% uranyl acetate and embedding in EPON or Polylite under vacuum. It was used embryos at young trochophore stage wich is characterized by active organogenesis. Some ultrastructural aspects of B. glabrata embryos cells are presented. (author)

  17. Investigation of molluscan phylogeny on the basis of 18S rRNA sequences.

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

    1996-12-01

    The 18S rRNA sequences of 12 molluscs, representing the extant classes Gastropoda, Bivalvia, Polyplacophora, Scaphopoda, and Caudofoveata, were determined and compared with selected known 18S rRNA sequences of Metazoa, including other Mollusca. These data do not provide support for a close relationship between Platyhelminthes (Turbellaria) and Mollusca, but rather suggest that the latter group belongs to a clade of eutrochozoan coelomates. The 18S rRNA data fail to recover molluscan, bivalve, or gastropod monophyly. However, the branching pattern of the eutrochozoan phyla and classes is unstable, probably due to the explosive Cambrian radiation during which these groups arose. Similarly, the 18S rRNA data do not provide a reliable signal for the molluscan interclass relationships. Nevertheless, we obtained strong preliminary support for phylogenetic inferences at more restricted taxonomic levels, such as the monophyly of Polyplacophora, Caenogastropoda, Euthyneura, Heterodonta, and Arcoida. PMID:8952075

  18. 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

    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

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

    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

  20. Biomphalaria subprona (Martens, 1899) (Gastropoda: Planorbidae)

    W. Lobato Paraense

    1996-01-01

    A description is given of the shell, head-foot, pulmonary wall, reproductive system and radula of Biomphalaria subprona (Martens, 1899). A diagnosis between it and two other congeneric species under 10 mm in shell diameter occurring in Middle America (Biomphalaria helophila and B. schrammi) is presented.

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

    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

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

    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

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

    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

  4. Fisiologia osmorregulatória em Mollusca

    Veiga, Marcos Paulo Trindade da

    2013-01-01

    Resumo: Os moluscos apresentam importante papel ecológico e econômico. A maior parte da produção nacional é dos bivalves Perna perna e Crassostrea gigas. Os quais estão sujeitos à predação do gastrópodo Stramonita brasiliensis. Estes animais estão sujeitos a variações ambientais. O objetivo deste trabalho foi avaliar as respostas comportamentais e fisiológicas dos moluscos diante de variações de fatores abióticos. No capítulo 1 foram caracterizadas as respostas fisiológicas de P. perna e C. g...

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

    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.

  6. Granular chitin in the epidermis of nudibranch molluscs.

    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

  7. Investigation of molluscan phylogeny using large-subunit and small-subunit nuclear rRNA sequences.

    Passamaneck, Yale J; Schander, Christoffer; Halanych, Kenneth M

    2004-07-01

    The Mollusca represent one of the most morphologically diverse animal phyla, prompting a variety of hypotheses on relationships between the major lineages within the phylum based upon morphological, developmental, and paleontological data. Analyses of small-ribosomal RNA (SSU rRNA) gene sequence have provided limited resolution of higher-level relationships within the Mollusca. Recent analyses suggest large-subunit (LSU) rRNA gene sequences are useful in resolving deep-level metazoan relationships, particularly when combined with SSU sequence. To this end, LSU (approximately 3.5 kb in length) and SSU (approximately 2 kb) sequences were collected for 33 taxa representing the major lineages within the Mollusca to improve resolution of intraphyletic relationships. Although the LSU and combined LSU+SSU datasets appear to hold potential for resolving branching order within the recognized molluscan classes, low bootstrap support was found for relationships between the major lineages within the Mollusca. LSU+SSU sequences also showed significant levels of rate heterogeneity between molluscan lineages. The Polyplacophora, Gastropoda, and Cephalopoda were each recovered as monophyletic clades with the LSU+SSU dataset. While the Bivalvia were not recovered as monophyletic clade in analyses of the SSU, LSU, or LSU+SSU, the Shimodaira-Hasegawa test showed that likelihood scores for these results did not differ significantly from topologies where the Bivalvia were monophyletic. Analyses of LSU sequences strongly contradict the widely accepted Diasoma hypotheses that bivalves and scaphopods are closely related to one another. The data are consistent with recent morphological and SSU analyses suggesting scaphopods are more closely related to gastropods and cephalopods than to bivalves. The dataset also presents the first published DNA sequences from a neomeniomorph aplacophoran, a group considered critical to our understanding of the origin and early radiation of the Mollusca

  8. Cercariae of the lakes Maarsseveen (Netherlands) infecting Bithynia spp. (Gastropoda: Prosobranchia) and Physa fontinalis (Gastropoda: Pulmonata)

    Keulen, Stef M.A.

    1981-01-01

    In 1978 cercariae have been collected from four species of freshwater snails in two lakes near Utrecht (Netherlands). Eleven species are recorded, of which six are described in detail. Five of these are new: Cercaria gutta n. sp. (Psilostomidae), C. cana n. sp. (Notocotilydae), C. quadrata n. sp. (Pleurogenetinae), C. abdita n. sp. and C. dyjannae n. sp. (both probably belonging to the Plagiorchiida, because they show characters of the group of Xiphidocercariae). Of C. dyjannae only the metac...

  9. Phylogenomics reveals deep molluscan relationships.

    Kocot, Kevin M; Cannon, Johanna T; Todt, Christiane; Citarella, Mathew R; Kohn, Andrea B; Meyer, Achim; Santos, Scott R; Schander, Christoffer; Moroz, Leonid L; Lieb, Bernhard; Halanych, Kenneth M

    2011-09-22

    Evolutionary relationships among the eight major lineages of Mollusca have remained unresolved despite their diversity and importance. Previous investigations of molluscan phylogeny, based primarily on nuclear ribosomal gene sequences or morphological data, have been unsuccessful at elucidating these relationships. Recently, phylogenomic studies using dozens to hundreds of genes have greatly improved our understanding of deep animal relationships. However, limited genomic resources spanning molluscan diversity has prevented use of a phylogenomic approach. Here we use transcriptome and genome data from all major lineages (except Monoplacophora) and recover a well-supported topology for Mollusca. Our results strongly support the Aculifera hypothesis placing Polyplacophora (chitons) in a clade with a monophyletic Aplacophora (worm-like molluscs). Additionally, within Conchifera, a sister-taxon relationship between Gastropoda and Bivalvia is supported. This grouping has received little consideration and contains most (>95%) molluscan species. Thus we propose the node-based name Pleistomollusca. In light of these results, we examined the evolution of morphological characters and found support for advanced cephalization and shells as possibly having multiple origins within Mollusca. PMID:21892190

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

    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.

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

    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

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

    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.

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

    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

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

    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

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

    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

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

    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.

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

    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.

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

    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

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

    Fischer, M. A.; Van der velde, 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 extend this description, paying special attention to the morphology, anatomy and histology of the digestive and reproductive system. Furthermore, new data on the morphology of the central nervous s...

  20. Diet of Lipophrys pholis (L.) (Teleostei, Blenniidae) in Cantabrian coastal waters (Spain)

    Mazé, Raquel A.; Domínguez, Josefa; Pérez-Cardenal, David

    1999-07-01

    Between February and December 1988, a total of 261 specimens of Lipophrys pholis were caught in eleven intertidal pools on the western coast of Asturias. This blenniid species mainly feeds on different groups of invertebrates, although algal remains also appear. Mollusca is the most highly represented taxon with the largest number of prey being Gastropoda, followed by Bivalvia and, to a lesser degree, Polyplacophora. Crustacea is well represented by Cirripedia. Isopoda also stands out and Amphipoda, Tanaidacea and Decapoda appear sporadically. Temporal diet analysis throughout the year shows no great differences. Likewise, a great similarity was observed among the feeding of L. pholis specimens collected in pools at a different tidal level, of variable size and with different algal cover. Changes in diet are appreciable as size increases, especially from a length of 6 cm on.

  1. Foods of Spectacled Eiders Somateria fischeri in the Bering Sea, Alaska

    Petersen, M.R.; Piatt, J.F.; Trust, K.A.

    1998-01-01

    The winter diet of Spectacled Eiders living in marine habitats is known only from two individuals described by Cottam (1939). Here we examine marine diets from 36 stomachs collected near St. Lawrence Island, Bering Sea, Alaska, during May-June in 1987 and 1992. All Spectacled Eiders ate Mollusca, including Gastropoda (snails; frequency of occurrence 20.0%; sole taxon 0.0%) and Bivalvia (bivalves; 80.0%; 48.0%), and Crustacea (barnacles, amphipods and crabs; 30.6%; 0.0%). One bird ate a cod. The predominant species group eaten was Macoma Clams (72.0%; 36.0%). Prey species of Spectacled Eiders occur predominantly in waters 25-60 m deep in the Bering Sea. To obtain these prey, especially the bivalves, on the winter area Spectacled Eiders must forage in waters exceeding 40 m. We speculate that Spectacled Eiders regularly forage at depths of 45-70 m throughout winter.

  2. Resolving the evolutionary relationships of molluscs with phylogenomic tools.

    Smith, Stephen A; Wilson, Nerida G; Goetz, Freya E; Feehery, Caitlin; Andrade, Sónia C S; Rouse, Greg W; Giribet, Gonzalo; Dunn, Casey W

    2011-12-15

    Molluscs (snails, octopuses, clams and their relatives) have a great disparity of body plans and, among the animals, only arthropods surpass them in species number. This diversity has made Mollusca one of the best-studied groups of animals, yet their evolutionary relationships remain poorly resolved. Open questions have important implications for the origin of Mollusca and for morphological evolution within the group. These questions include whether the shell-less, vermiform aplacophoran molluscs diverged before the origin of the shelled molluscs (Conchifera) or lost their shells secondarily. Monoplacophorans were not included in molecular studies until recently, when it was proposed that they constitute a clade named Serialia together with Polyplacophora (chitons), reflecting the serial repetition of body organs in both groups. Attempts to understand the early evolution of molluscs become even more complex when considering the large diversity of Cambrian fossils. These can have multiple dorsal shell plates and sclerites or can be shell-less but with a typical molluscan radula and serially repeated gills. To better resolve the relationships among molluscs, we generated transcriptome data for 15 species that, in combination with existing data, represent for the first time all major molluscan groups. We analysed multiple data sets containing up to 216,402 sites and 1,185 gene regions using multiple models and methods. Our results support the clade Aculifera, containing the three molluscan groups with spicules but without true shells, and they support the monophyly of Conchifera. Monoplacophora is not the sister group to other Conchifera but to Cephalopoda. Strong support is found for a clade that comprises Scaphopoda (tusk shells), Gastropoda and Bivalvia, with most analyses placing Scaphopoda and Gastropoda as sister groups. This well-resolved tree will constitute a framework for further studies of mollusc evolution, development and anatomy. PMID:22031330

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

    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.

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

    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.

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

    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

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

    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.

  7. Familia Ellobiidae (Gastropoda: Archaeopulmonata en el litoral peruano

    Carlos Paredes

    2013-05-01

    Full Text Available Se reportan 8 especies de Ellobiidae para la Costa Peruana, pertenecientes a las subfamilias Ellobiinae: Ellobium stagnale (Orbigny, 1835 y Sarnia frumentum Petit, 1842; Melampodinae: Melampus carolianus (Lesson, 1842, Melampus olivaceus Carpenter, 1857 y Detracia graminea Morrison, 1846; y Pedipedinae: Marinula acuta (Orbigny, 1835, Marinula concinna (C.B Adams, 1852 y Marinula pepita King, 1831. Seis especies viven asociadas al bosque de manglar en el departamento de Tumbes, y dos en las playas de canto rodado en los límites de la Provincia Peruana. Cuatro especies tropicales se registran por primera vez para el mar peruano: E. stagnale, M. olivaceus, D. graminea y M. acuta.

  8. Familia Ellobiidae (Gastropoda: Archaeopulmonata) en el litoral peruano

    Carlos Paredes; Aldo Indacochea; Franz Cardoso; Kelly Ortega

    2013-01-01

    Se reportan 8 especies de Ellobiidae para la Costa Peruana, pertenecientes a las subfamilias Ellobiinae: Ellobium stagnale (Orbigny, 1835) y Sarnia frumentum Petit, 1842; Melampodinae: Melampus carolianus (Lesson, 1842), Melampus olivaceus Carpenter, 1857 y Detracia graminea Morrison, 1846; y Pedipedinae: Marinula acuta (Orbigny, 1835), Marinula concinna (C.B Adams, 1852) y Marinula pepita King, 1831. Seis especies viven asociadas al bosque de manglar en el departamento de Tumbes, y dos en la...

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

    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

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

    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

  11. Lymnaea cousini Jousseaume, 1887, from Ecuador (Gastropoda: Lymnaeidae)

    W. Lobato Paraense

    1995-01-01

    A description is given of the shell, renal organ, reproductive system and radula of topotypic specimens of Lymnaea cousini Jousseaume, 1887. A diagnosis between it and four other lymnaeids which also occur in South America and were previously studied by the author (L. columella, L. diaphana, L. viatrix and L. rupestris) is presented.

  12. Lymnaea cousini Jousseaume, 1887 (Gastropoda: Lymnaeidae): first record for Venezuela

    Pointier JP; O Noya; M Amarista; Théron, A.

    2004-01-01

    Lymnaea cousini Jousseaume, 1887 was collected in Mucubaji, Merida State, Venezuela, from a permanent pond located at a very high altitude (3760 m). Identification of the collected specimens was made by comparison with the original description of the shell by Jousseaume and the description of the renal organ and reproductive system of topotypic specimens by Paraense.

  13. Biomphalaria prona (Gastropoda: Planorbidae: a morphological and biochemical study

    W. Lobato Paraense

    1992-06-01

    Full Text Available Two samples of Biomphalaria prona (Martens, 1873 from Lake Valencia (type locality and seven from other Venezuelan localities were studied morphologically (shell and reproductive system and biochemically (allozyme electrophoresis. In spite of marked differences in shell characters, all of them proved indistinguishable under the anatomic and biochemical criteria. So far B. prona has been considered an endemic species, restricted to Lake Valencia. It is now demonstrated that the extralacustrine populations refered to Biomphalaria havanensis (Pfeiffer, 1839 by several authors correspond in shell characters to an extreme variant of B. prona from the Lake and really belong to the last*mentioned species. They may be regarded as the result of a process of directional selection favoring a shell phenotype other than those making up the modal class in the Lake.

  14. Biomphalaria prona (Gastropoda: Planorbidae): a morphological and biochemical study

    W. Lobato Paraense; Pointier, J.P.; Delay, B.; A. F. Pernot; Incani, R N; C. Balzan; P. Chrosciechowski

    1992-01-01

    Two samples of Biomphalaria prona (Martens, 1873) from Lake Valencia (type locality) and seven from other Venezuelan localities were studied morphologically (shell and reproductive system) and biochemically (allozyme electrophoresis). In spite of marked differences in shell characters, all of them proved indistinguishable under the anatomic and biochemical criteria. So far B. prona has been considered an endemic species, restricted to Lake Valencia. It is now demonstrated that the extralacust...

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

    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.

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

    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

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

    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

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

    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

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

    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...

  20. Reproduction of Omalonyx matheroni (Gastropoda: Succineidae under laboratory conditions

    Lângia Montresor

    2012-06-01

    Full Text Available The life histories of succineids have received relatively little attention. To evaluate life history characteristics of Omalonyx matheroni, we studied a Brazilian population (Reserva Particular do Patrimônio Natural Feliciano Miguel Abdala, in Caratinga, Minas Gerais, Brazil under laboratory conditions. The aims of the present study were (1 to describe in detail an appropriate rearing method; (2 to investigate the effects of different temperature and photoperiod conditions; and (3 to assess the effects of self and cross-fertilization on the reproductive biology of these mollusks. We studied the oviposition site, the time to sexual maturity and the influences of photoperiod and temperature on reproductive parameters of O. matheroni reared under laboratory conditions. We tested three combinations of temperature and photoperiod, designated A, B and C (A: 25ºC, 24 hours of light; B: environmental conditions of temperature and photoperiod, characterized as follows: average máximum temperature=27.1ºC, average minimum temperature=18.3ºC, average day length=12.06 hours; and C: 25ºC, zero hours of light and two rearing densities (I: isolated and G: grouped on reproductive parameters (number of eggs per egg mass, number of unviable eggs per mass, egg mass incubation period, and duration of the hatching period. A total of 186 individuals and 565 egg masses were studied. Data were analyzed by Student’s t-test, two-way ANOVA and Chi-Square test. Eight generations were produced (March/2004-March/2006, from 35 field specimens, 91% of 3 197 eggs hatched. The time to sexual maturity was approximately three months for individuals reared in groups or in isolation (Student’s t-test: t=1.41, df=31, p=0.16; however, they differed significantly in weight (Student’s t-test: t=3.6, df=31, p<0.001. Regarding the influences of temperatura and photoperiod on reproductive parameters, under natural environmental conditions, individuals produced a greater number of eggs per mass (ANOVA: F2,573=84.15, p<0.001, with a longer incubation period (ANOVA: F2;559=170.05, p<0.001. The extreme photoperiod conditions of 24 hours of light or zero hours of light likely imposed stress and could be related to the significant reductions in the number of eggs per mass, and egg incubation period as well as the increased synchrony in egg hatching. No correlations were observed between the number of unviable eggs per mass and the temperature, photoperiod (ANOVA: F2,573=0.87, p=0.92 or rearing density (ANOVA: F1,573=0.21, p=0.64. Individuals reared in isolation under natural conditions produced more eggs per mass and did not presented any disadvantage with respect to the variables analyzed as compared to the animals reared in groups. These results indicate that O. matheroni can successfully reproduce by selfing. Rev. Biol. Trop. 60 (2: 553-566. Epub 2012 June 01.

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

    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

  2. La Familia Calyptraeidae en el Perú (Gastropoda: Caenogastropoda)

    Carlos Paredes; Franz Cardoso

    2013-01-01

    En el presente trabajo se realiza una revisión taxonómica de la familia Calyptraeidae Lamarck, 1809, en la costa Peruana. Se confirma la presencia de 17 especies de las 19 reportadas por diversos autores. Crepidula arenata (Broderip, 1834) es sinónimo de C. excavata (Broderip, 1834). Se da información sobre la distribución geográfica y algunas relaciones ecológicas.

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

    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.

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

    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.

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

    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...

  6. Yochelcionella (Mollusca, Helcionelloida) from the lower Cambrian of North America

    Atkins C J; Peel J S

    2008-01-01

    Five named species of the helcionelloid mollusc genus Yochelcionella Runnegar & Pojeta, 1974 are recognized from the lower Cambrian (Cambrian Series 2) of North America: Yochelcionella erecta (Walcott, 1891), Y. americana Runnegar &Pojeta, 1980, Y. chinensis Pei, 1985, Y. greenlandica Atkins & Peel, 2004 and Y. gracilis Atkins & Peel, 2004, linking lower Cambrian o...

  7. Protandric hermaphroditism in the bivalve Arca noae (Mollusca: Arcidae

    G. BELLO

    2013-04-01

    Full Text Available Following the histological analysis of Arca noae samples from the south-western Adriatic Sea, five hermaphroditic specimens were found out of 168 sexed individuals (3.0%. The hermaphrodite gonads showed the co-occurrence of male and female germ cells within the same acini, i.e. both spermatozoa in the lumen and oogonia lining its wall. Oogonia increased in size through winter, thus suggesting that the direction of sex change is from male to female. Both the biometrical analyses and theoretical considerations strongly suggest that A. noae is an obligate protandric species.

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

    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.

  9. Neuronal development in larval chiton Ischnochiton hakodadensis (Mollusca: Polyplacophora).

    Voronezhskaya, Elena E; Tyurin, Sergei A; Nezlin, Leonid P

    2002-02-25

    Chitons are the most primitive molluscs and, thus, a matter of considerable interest for understanding both basic principles of molluscan neurogenesis and phylogeny. The development of the nervous system in trochophores of the chiton Ischnochiton hakodadensis from hatching to metamorphosis is described in detail by using confocal laser scanning microscopy and antibodies raised against serotonin, FMRFamide, and acetylated alpha tubulin. The earliest nervous elements detected were peripheral neurons located in the frontal hemisphere of posthatching trochophores and projecting into the apical organ. Among them, two pairs of unique large lateral cells appear to pioneer the pathways of developing adult nervous system. Chitons possess an apical organ that contains the largest number of neurons among all molluscan larvae investigated so far. Besides, many pretrochal neurons are situated outside the apical organ. The prototroch is not innervated by larval neurons. The first neurons of the developing adult central nervous system (CNS) appear later in the cerebral ganglion and pedal cords. None of the neurons of the larval nervous system are retained in the adult CNS. They cease to express their transmitter content and disintegrate after settlement. Although the adult CNS of chitons resembles that of polychaetes, their general scenario of neuronal development resembles that of advanced molluscs and differs from annelids. Thus, our data demonstrate the conservative pattern of molluscan neurogenesis and suggest independent origin of molluscan and annelid trochophores. PMID:11835180

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

    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

  11. [Chitons (Mollusca: Polyplacophora) from El Salvador, Central America].

    García-Ríos, Cedar I; Alvarez-Ruiz, Migdalia; Barraza, José E; Rivera, Ana M; Hasbún, Carlos R

    2007-03-01

    Collections of 11 species of shallow water Polyplacophora from El Salvador were made in July 2002. Previously only five species had been documented in El Salvador: Chaetopleura lurida (Sowerby, 1832); Ischnochiton guatemalensis (Thiele, 1910); Ceratozona angusta (Thiele, 1909); Chiton stokesii (Broderip, 1832) and Acantochitona exquisita (Pilsbry, 1893). Of these, L. guatemalensis and A. exquisita were not collected in this census. Seven other species are reported here for El Salvador for the first time: Lepidochitona beanii (Carpenter, 1857); Ischnochiton dispar (Sowerby, 1832); Stenoplax limaciformis (Sowerby, 1832); Callistochiton expressus (Carpenter, 1865); Acanthochitona arragonites (Carpenter, 1867); A. ferreirai (Lyons, 1988) and A. hirudiniformis (Sowerby, 1832). The known geographic distribution of 1. dispar is extended to the north. An un-named species of Lepidochitona is briefly described. PMID:18457124

  12. Chemotactic behavior of the sperm of chitons (Mollusca: Polyplacophora).

    Miller, R L

    1977-11-01

    Observations of sperm behavior in the vicinity of gradients of egg-water or alcohol extracts of whole freshly-spawned eggs of several chitons reveal what appear to be directed movements of sperm up the gradient, resulting in the aggregation of motile sperm at the gradient source. Plots of the tracks of the sperm approaching the gradient source show that the cells increase the time during which they move toward the source and decrease the time spent moving away. Although this resembles the kinesis behavior shown by bacteria in a gradient, the path directions are markedly non-random. The reorientation behavior of thigmotactic sperm involves enlargement of the normal circular path diameter in the direction of the source and an alternation of tight loops and wide circular arcs, with the latter made in the direction of the source. The form of the path of attracted chiton sperm is like that observed during chemotaxis of the sperm of the hydroid Tubularia and the tunicate Ciona and resembles the behavior of Ciona sperm in that there is no increase in velocity as the cells move up the gradient. However, unlike the cnidarian and urochordate cases, the attracting substances extracted from chiton eggs do not act species-specifically. PMID:925668

  13. Upper Cambrian chitons (Mollusca, polyplacophora) from Missouri, USA

    Pojeta, J., Jr.; Vendrasco, M.J.; Darrough, G.

    2010-01-01

    Numerous new specimens reveal a greater presence of chitons in Upper Cambrian rocks than previously suspected. Evidence is presented showing that the chiton esthete sensory system is present in all chiton species in this study at the very beginning of the known polyplacophoran fossil record. The stratigraphic occurrences and paleobiogeography of Late Cambrian chitons are documented. The 14 previously-named families of Cambrian and Ordovician chitons are reviewed and analyzed. Aulochitonidae n. fam. is defined, based on Aulochiton n. gen.; A. sannerae n. sp. is also defined. The long misunderstood family Preacanthochitonidae and its type genus Preacanthochiton Bergenhayn, 1960, are placed in synonymy with Mattheviidae and Chelodes Davidson & King, 1874, respectively; Eochelodes Marek, 1962, also is placed in synonymy with Chelodes, and Elongata Stinchcomb & Darrough, 1995, is placed in synonymy with Hemithecella Ulrich & Bridge, 1941. At the species level, H. elongata Stinchcomb & Darrough, 1995, and Elongata perplexa Stinchcomb & Darrough, 1995, are placed in synonymy with H. eminensis Stinchcomb & Darrough, 1995. The Ordovician species H. abrupta Stinchcomb & Darrough, 1995, is transferred to the genus Chelodes as C. abrupta (Stinchcomb & Darrough, 1995). The Ordovician species Preacanthochiton baueri Hoare & Pojeta, 2006, is transferred to the genus Helminthochiton as H. ? baueri (Hoare & Pojeta, 2006). The Ordovician species H. marginatus Hoare & Pojeta, 2006, is transferred to the genus Litochiton as L. marginatus (Hoare & Pojeta, 2006). Matthevia walcotti Runnegar, Pojeta, Taylor, & Collins, 1979, is treated as a synonym of Hemithecella expansa Ulrich & Bridge, 1941. In addition, other multivalved Cambrian mollusks are discussed; within this group, Dycheiidae n. fam. is defined, as well as Paradycheia dorisae n. gen. and n. sp. Cladistic analysis indicates a close relationship among the genera here assigned to the Mattheviidae, and between Echinochiton Pojeta, Eernisse, Hoare, & Henderson, 2003, and mattheviids. The results suggest treating these taxa as stem-lineage chitons, and do not support the hypothesis that they are aplacophorans.

  14. Complete male mitochondrial genome of Anodonta anatina (Mollusca: Unionidae).

    Soroka, Marianna; Burzyński, Artur

    2016-05-01

    Anodonta anatina is a freshwater mussel of the family Unionidae. These mussels have a unique mitochondria inheritance system named doubly uniparental inheritance (DUI). Under DUI males have two, potentially very divergent mitochondrial genomes: F-type inherited from mother and M-type inherited from father. F-type is present in soma whereas M-type is present in gonadal tissues and sperm. Here we report two M-type sequences of complete mitochondrial genomes from Anodonta anatina. They are 16,906 bp long and their sequences are similar (0.1% divergence). The genome organization is identical to the other Unionidean M-type genomes published to date. There are 38 genes, including the recently described M-type specific M ORF. The presence of tRNA-like repeat in one of the noncoding regions, suggests that the control region is located in this area. Nucleotide composition is quite extreme, with AT content (66.2%) higher than in any other of the six published Unionidean M genomes. PMID:25317641

  15. Biodiversity and biogeography of Antarctic and sub-Antarctic mollusca

    Linse, Katrin; Griffiths, Huw J.; Barnes, David K. A.; Clarke, Andrew

    2006-04-01

    For many decades molluscan data have been critical to the establishment of the concept of a global-scale increase in species richness from the poles to the equator. Low polar diversity is key to this latitudinal cline in diversity. Here we investigate richness patterns in the two largest classes of molluscs at both local and regional scales throughout the Southern Ocean. We show that biodiversity is very patchy in the Southern Ocean (at the 1000-km scale) and test the validity of historical biogeographic sub-regions and provinces. We used multivariate analysis of biodiversity patterns at species, genus and family levels to define richness hotspots within the Southern Ocean and transition areas. This process identified the following distinct sub-regions in the Southern Ocean: Antarctic Peninsula, Weddell Sea, East Antarctic—Dronning Maud Land, East Antarctic—Enderby Land, East Antarctic—Wilkes Land, Ross Sea, and the independent Scotia arc and sub Antarctic islands. Patterns of endemism were very different between the bivalves and gastropods. On the basis of distributional ranges and radiation centres of evolutionarily successful families and genera we define three biogeographic provinces in the Southern Ocean: (1) the continental high Antarctic province excluding the Antarctic Peninsula, (2) the Scotia Sea province including the Antarctic Peninsula, and (3) the sub Antarctic province comprising the islands in the vicinity of the Antarctic Circumpolar Current.

  16. Planorbidae, Lymnaeidae and Physidae of Peru (Mollusca: Basommatophora

    Paraense W Lobato

    2003-01-01

    Full Text Available In the course of several trips to Peru I had the opportunity of collecting topotypic specimens of Biomphalaria andecola (Orbigny, 1835, B. helophila (Orbigny, 1835, B. pucaraensis (Preston, 1909, Drepanotrema limayanum (Lesson, 1830, D. kermatoides (Orbigny, 1835, and Lymnaea viatrix Orbigny, 1835, besides B. tenagophila (Orbigny, 1835, Helisoma trivolvis (Say, 1817, H. duryi (Wetherby, 1879, Physa acuta Draparnaud, 1801, and seemingly P. peruviana Gray, 1828. B. pucaraensis is considered a junior synonym of B. peregrina (Orbigny, 1835.

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

    Sonia Barbosa dos Santos

    1994-01-01

    A new species of Gundlachia, Gundlachia dutrae is described from northwest Brazil. It is distinguishable from other congenerie species by characteristics of the shell, radula and internal organs. Shell relatively high. Aperture near-circular; periostracum dark brown without periostracal hairs. Apex slightly inclined to the right, projected but not hooked, with an apical depression surrounted by a sculpture of well-marked irregular punctations. Shell surface with prominent radial sculpture. No...

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

    Silvana C. Thiengo; Carlos E. Borda; J. L. Barros Araújo

    1993-01-01

    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, ...

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

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

    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

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

    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.

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

    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

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

    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.

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

    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

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

    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%.

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

    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.

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

    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...

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

    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

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

    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

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

    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....

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

    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

  12. Bioactive molecules from sea hares.

    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

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

    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

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

    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

  15. Conquiliomorfologia de Tamayoa (Tamayops) banghaasi (Thiele) (Gastropoda, Systrophiidae) Conchomorphological aspects of Tamayoa (Tamayops) banghaasi (Thiele) (Gastropoda, Systrophiidae) as a contribution to Systrophiidae systematic

    Daniele Pedrosa Monteiro; Sônia Barbosa dos Santos

    2001-01-01

    Thirty shells of Tamayoa (Tamayops) banghaasi (Thiele, 1927) from Ilha Grande, Rio de Janeiro, were analyzed with a stereomicroscop showing the following characteristics: discoid shell, without macrosculptures; ovate-lunate aperture without teeth. Thin, sharp and not-reflected lip; umbilicus with 1/5 of the shell's diameter; impressed suture, total whorls from 4 to 5.5; protoconch with 1.5 to 2 whorls; yellowish-amber, translucent and glossy periostracum. The morphology of the shells were dis...

  16. Microescultura da concha de Rectartemon (Rectartemon) depressus (Heynemann) (Gastropoda, Stylomatophora, Streptaxidae) The microsculpture of the shell of Rectaktbmon (Rectíartemon) depressus (Heynemann) (Gastropoda, Stylomatophora, Streptaxidae)

    Mônica Picoral; Vera Lúcia Lopes-Pitoni

    1998-01-01

    The microsculpture of Rectartemon depressus (Heynemann, 1868) shell is described on scanning electron microscope. The generics characteristics are proposed: shell's dorsal sculture formed for ribs striae radial; nuclear whorls smooth; ventral surface of the shell smooth or slightly striate; and as specifics characteristics: the number of ribs striae radial on the last world. The R. (R.) depressus presented seven or eight ribs striae radial for millimeter.

  17. Ancylidae (Gastropoda, Basommatophora) na América do Sul: sistemática e distribuição South American Ancylidae (Gastropoda, Basommatophora): systematic and distribution

    Rosane Lanzer

    1996-01-01

    The family Ancylidae is represented in South America by the genera: Gundlachia Pfeiffer, 1849, Ferrissia Walker, 1903, Burnupia Walker, 1912 and Laevapex Walker, 1903. The species are caracterized using the combination of shell features and radula by scanning electron microscope, shell muscle and mantle pigmentation. The conchometry is also presented, but it does not help to species identification. The distribution of G. crequi (Bavay, 1904), G. foncki (Philippi, 1866), G. philippiana (Biese,...

  18. A review of the Veronicellidae from Mexico (Gastropoda: Soleolifera) Revisión de los Veronicellidae de México (Gastropoda: Soleolifera)

    Edna Naranjo-García; José Willibaldo Thomé; José Castillejo

    2007-01-01

    Information is presented regarding the species of the Family Veronicellidae in Mexico. Data were gathered from specimens deposited in the Colección Nacional de Moluscos (Instituto de Biología, Universidad Nacional Autónoma de México), from field trips, and from the literature. These slugs are distributed mainly in the central and southern regions of Mexico, although there are a few records from the northern part of the country. Five species in three genera have been recorded, namely: Leidyula...

  19. A review of the Veronicellidae from Mexico (Gastropoda: Soleolifera Revisión de los Veronicellidae de México (Gastropoda: Soleolifera

    Edna Naranjo-García

    2007-06-01

    Full Text Available Information is presented regarding the species of the Family Veronicellidae in Mexico. Data were gathered from specimens deposited in the Colección Nacional de Moluscos (Instituto de Biología, Universidad Nacional Autónoma de México, from field trips, and from the literature. These slugs are distributed mainly in the central and southern regions of Mexico, although there are a few records from the northern part of the country. Five species in three genera have been recorded, namely: Leidyula floridana, L. moreleti, Phyllocaulis gayi, Sarasinula dubia and S. plebeia. The occurrence of Leidyula floridana and Phyllocaulis gayi in Mexico needs confirmation. The Los Tuxtlas region, southern Veracruz, is a hotspot where veronicellid slugs have become a pest and farmers have stopped growing beans, switching to other crops as a measure to contain the pest.Se sintetiza la información conocida de los Veronicellidae de México. Los datos provienen de ejemplares depositados en la Colección Nacional de Moluscos, Instituto de Biología, Universidad Nacional Autónoma de México, de salidas complementarias de trabajo al campo y recopilación de la literatura. Estas babosas se distribuyen principalmente en el centro y sur de México, aunque existen algunos registros en el norte del país. Se han registrado 3 géneros y 5 especies: Leidyula floridana, L. moreleti, Phyllocaulis gayi, Sarasinula dubia, y S. plebeia. Los registros en México de L. floridana y P. gayi deben confirmarse. En la región de Los Tuxtlas, al sur del estado de Veracruz, se localizó un foco donde las babosas Veronicellidae son plaga, los agricultores dejaron de sembrar frijol y cambiaron a otros cultivos para evitar la plaga.

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

    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.

  1. Report of a human accident caused by Conus regius (Gastropoda, Conidae) Relato de um acidente em ser humano causado por Conus regius (Gastropoda, Conidae)

    Vidal Haddad Junior; Marcus Coltro; Luiz Ricardo L. Simone

    2009-01-01

    Conus regius is a venomous mollusc in the Conidae family, which includes species responsible for severe or even fatal accidents affecting human beings. This is the first report on a clinical case involving this species. It consisted a puncture in the right hand of a diver who presented paresthesia and movement difficulty in the whole limb. The manifestations disappeared after around twelve hours, without sequelae.Conus regius é um molusco venenoso da família Conidae, que inclui espécies respo...

  2. Report of a human accident caused by Conus regius (Gastropoda, Conidae Relato de um acidente em ser humano causado por Conus regius (Gastropoda, Conidae

    Vidal Haddad Junior

    2009-08-01

    Full Text Available Conus regius is a venomous mollusc in the Conidae family, which includes species responsible for severe or even fatal accidents affecting human beings. This is the first report on a clinical case involving this species. It consisted a puncture in the right hand of a diver who presented paresthesia and movement difficulty in the whole limb. The manifestations disappeared after around twelve hours, without sequelae.Conus regius é um molusco venenoso da família Conidae, que inclui espécies responsáveis por acidentes graves ou mesmo fatais em humanos. Os autores relatam pela primeira vez um caso clínico envolvendo a espécie, que inclui uma punctura na mão direita de um mergulhador submarino, que apresentou parestesias e dificuldade de movimentação do membro todo. O quadro desapareceu em cerca de doze horas, sem seqüelas.

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

    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.

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

    Édgar Suarez B; Álvaro Castaing R

    2016-01-01

    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, 3)Pelliciera rhizoph...

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

    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.

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

    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.

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

    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.

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

    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.

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

    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.

  10. Evolution of phosphagen kinase V. cDNA-derived amino acid sequences of two molluscan arginine kinases from the chiton Liolophura japonica and the turbanshell Battilus cornutus.

    Suzuki, T; Ban, T; Furukohri, T

    1997-06-20

    The cDNAs of arginine kinases from the chiton Liolophura japonica (Polyplacophora) and the turbanshell Battilus cornutus (Gastropoda) were amplified by polymerase chain reaction (PCR), and the complete nucleotide sequences of 1669 and 1624 bp, respectively, were determined. The open reading frame for Liolophura arginine kinase is 1050 nucleotides in length and encodes a protein with 349 amino acid residues, and that for Battilus is 1077 nucleotides and 358 residues. The validity of the cDNA-derived amino acid sequence was supported by chemical sequencing of internal tryptic peptides. The molecular masses were calculated to be 39,057 and 39,795 Da, respectively. The amino acid sequence of Liolophura arginine kinase showed 65-68% identity with those of Battilus and Nordotis (abalone) arginine kinases, and the homology between Battilus and Nordotis was 79%. Molluscan arginine kinases also show lower, but significant homology (38-43%) with rabbit creatine kinase. The sequences of arginine kinases could be used as a molecular clock to elucidate the phylogeny of Mollusca, one of the most diverse animal phyla. PMID:9217008

  11. Additions to the knowledge of the land snails of Sabah (Malaysia, Borneo), including 48 new species

    Vermeulen, Jaap J.; Liew, Thor-Seng; Schilthuizen, Menno

    2015-01-01

    Abstract We present reviews of the Sabah (Malaysia, on the island of Borneo) species of the following problematical genera of land snails (Mollusca, Gastropoda): Acmella and Anaglyphula (Caenogastropoda: Assimineidae); Ditropopsis (Caenogastropoda: Cyclophoridae); Microcystina (Pulmonata: Ariophantidae); Philalanka and Thysanota (Pulmonata: Endodontidae); Kaliella, Rahula, (Pulmonata: Euconulidae); Trochomorpha and Geotrochus (Pulmonata: Trochomorphidae). Next to this, we describe new species in previously revised genera, such as Diplommatina (Diplommatinidae); Georissa (Hydrocenidae); as well as some new species of genera not revised previously, such as Japonia (Cyclophoridae); Durgella and Dyakia (Ariophantidae); Amphidromus, and Trachia (Camaenidae); Paralaoma (Punctidae); Curvella (Subulinidae). All descriptions are based on the morphology of the shells. We distinguish the following 48 new species: Acmella cyrtoglyphe, Acmella umbilicata, Acmella ovoidea, Acmella nana, Acmella subcancellata, Acmella striata, and Anaglyphula sauroderma (Assimineidae); Ditropopsis davisoni, Ditropopsis trachychilus, Ditropopsis constricta, Ditropopsis tyloacron, Ditropopsis cincta, and Japonia anceps (Cyclophoridae); Diplommatina bidentata and Diplommatina tylocheilos (Diplommatinidae); Georissa leucococca and Georissa nephrostoma (Hydrocenidae); Durgella densestriata, Dyakia chlorosoma, Microcystina microrhynchus, Microcystina callifera, Microcystina striatula, Microcystina planiuscula, and Microcystina physotrochus (Ariophantidae); Amphidromus psephos and Trachia serpentinitica (Camaenidae); Philalanka tambunanensis, Philalanka obscura, Philalanka anomphala, Philalanka rugulosa, and Philalanka malimgunung (Endodontidae); Kaliella eurytrochus, Kaliella sublaxa, Kaliella phacomorpha, Kaliella punctata, Kaliella microsoma, Rahula delopleura, (Euconulidae); Paralaoma angusta (Punctidae); Curvella hadrotes (Subulinidae); Trochomorpha trachus, Trochomorpha haptoderma, Trochomorpha

  12. A neurophylogenetic approach provides new insight to the evolution of Scaphopoda.

    Sumner-Rooney, Lauren H; Schrödl, Michael; Lodde-Bensch, Eva; Lindberg, David R; Heß, Martin; Brennan, Gerard P; Sigwart, Julia D

    2015-01-01

    The position of scaphopods in molluscan phylogeny remains singularly contentious, with several sister relationships supported by morphological and phylogenomic data: Scaphopoda + Bivalvia (Diasoma), Scaphopoda + Cephalopoda (Variopoda), and Scaphopoda + Gastropoda. Nervous system architecture has contributed significant insights to reconstructing phylogeny in the Mollusca and other invertebrate groups, but a modern neurophylogenetic approach has not been applied to molluscs, hampered by a lack of clearly defined homologous characters that can be unequivocally compared across the radical body plan disparity among the living clades. We present the first three-dimensional reconstruction of the anterior nervous system of a scaphopod, Rhabdus rectius, using histological tomography. We also describe a new putative sensory organ, a paired and pigmented sensory mantle slit. This structure is restricted to our study species and not a general feature of scaphopods, but it forms an integral part of the description of the nervous system in R. rectius. It also highlights the potential utility of neuro-anatomical characters for multiple levels of phylogenetic inference beyond this study. This potential has not previously been exploited for the thorny problem of molluscan phylogeny. The neuroanatomy of scaphopods demonstrates a highly derived architecture that shares a number of key characters with the cephalopod nervous system, and supports a Scaphopoda + Cephalopoda grouping. PMID:26487042

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

    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.

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

    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

  15. 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

    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.

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

    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...

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

    Lindsay, Tabitha

    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

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

    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

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

    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.

  20. Freshwater snail Pomacea bridgesii (Gastropoda: Ampullariidae), life history traits and aquaculture potential

    Ana R. A. Coelho; Gonçalo J. P. Calado; Maria T. Dinis

    2012-01-01

    Investigations on the reproductive biology, life cycle and feeding habits of Pomacea bridgesiihave been undertaken to assess its potential as a cultured species for the ornamental trade. The speciesis dioecious and, under optimal culture conditions of temperature and food supply, it can breed all yearround. The total developmental period at 23±1ºC varied from 15 to 24 days after oviposition. Hatchingcan last for up to 20 hours in the same egg cluster. Hatching success was very high (mean94.56...

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

    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...

  2. Terrestrial gastropods of Srebarna Nature Reserve, North-Eastern Bulgaria (Gastropoda

    Ivailo Dedov

    2015-01-01

    Full Text Available We give the results from the first investigation focused on the land snail fauna in Srebarna Nature Reserve in Bulgaria. A total of 23 localities were studied and 27 species of terrestrial gastropods were found, 23 of which were new observations for the Reserve.

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

    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 ...

  4. Four marine digenean parasites of Austrolittorina spp. (Gastropoda: Littorinidae) in New Zealand: morphological and molecular data

    O'Dwyer, K.; Blasco-Costa, I.; Poulin, R.; Faltýnková, Anna

    2014-01-01

    Roč. 89, č. 2 (2014), s. 133-152. ISSN 0165-5752 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Trematode parasites * life cycles * intertidal ecosystems * phylogenetics analysis * SW Iceland * Notocotylidae * history * snail Subject RIV: EG - Zoology Impact factor: 1.336, year: 2014

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

    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.

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

    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.

  7. First occurrence of Schistosomatidae infecting Aplexa hypnorum (Gastropoda, Physidae) in France

    Gérard C.

    2004-01-01

    Due to the recrudescence of cercarial dermatitis in the world, larval Schistosomatidae have been researched during 20 months in gastropods of stagnant fresh waters in a wetland. Brevifurcate ocellate cercariae have been detected after crushing in a species of Physidae, Aplexa hypnorum, with a prevalence of 6.52 %. Up to now, this species had never been found infected by larval trematodes. Lymnaeidae, Planorbidae and other Physidae didn't harbour schistosomatids. Cercariae of A. hypnorum prese...

  8. Larval trematode infections in Galba truncatula (Gastropoda, Lymnaeidae) from the Brenne Regional Natural Park, central France.

    Rondelaud, D; Vignoles, P; Dreyfuss, G

    2016-05-01

    Adult Galba truncatula ( ≥ 4 mm in shell height) were collected from 135 habitats for 3 years (2012-2014) to identify parasite species via the study of cercariae, and to determine the prevalence of each digenean infection in relation to the type of snail habitat (six types). A total of 323 infected snails and ten digenean species were noted in the bodies of 11,025 G. truncatula after their dissection. Snails with Calicophoron daubneyi and/or Fasciola hepatica were found in 20.7% and 12.5% of the habitats, respectively, and most of these infected snails were collected from rainwater-draining furrows and pools in meadows. The percentages were lower for snails with Echinostoma revolutum (9.6% of habitats) and Haplometra cylindracea (7.4%), and were less than 5% for those parasitized by any of the other five species of digenean. The highest prevalence of all digenean infections was noted in pools (9.4%), followed by furrows located in meadows (8.3%) and ponds (5.1%). The prevalence noted for each digenean infection varied with the type of habitat. In furrows located in meadows, the infection rate of C. daubneyi in snails (3.5%) was significantly higher than that of F. hepatica (2.2%). In pools, values greater than 1.5% were noted for C. daubneyi, H. cylindracea and Opistoglyphe ranae. In ponds, E. revolutum was the dominant species (prevalence, 2.5%). Parasite species richness in G. truncatula was greater in the Brenne Natural Regional Park than in the nearby region of Limousin (ten instead of eight). The distribution and prevalence of each parasite species were dependent on the type and location of each snail habitat. PMID:25804319

  9. A new species of Leiostracus from Bahia, Brazil (Gastropoda, Pulmonata, Orthalicidae

    Rodrigo B. Salvador

    2014-03-01

    Full Text Available A remarkable new species of pulmonate snail was recently collected in a small Atlantic Rainforest fragment near the city of Canavieiras, state of Bahia, Brazil, an area known for a high diversity of land snails. It is described herein as Leiostracus fetidus sp. nov. and can be easily identified by its color pattern of irregular brown to black axial stripes on a white to yellow background, a reddish axial band "separating" the white peristome from the rest of the shell and a broad brown spiral band surrounding the umbilical region. Other diagnostic features include a relatively small size, a proto columellar fold and two very weak folds delimiting the basal region of the aperture. This discovery is a reminder of how little this fauna is known and also an alarm for proper conservation of these forest fragments.

  10. A Tale That Morphology Fails to Tell: A Molecular Phylogeny of Aeolidiidae (Aeolidida, Nudibranchia, Gastropoda)

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

    2013-01-01

    Aeolidida is one of the largest clades of nudibranchs with at least 560 known species. However, its systematics has not been studied in a comprehensive manner. Phylogenetic analyses of larger clades such as Nudibranchia or Cladobranchia have usually included a poor sample of aeolids. Furthermore, phylogenetic studies at the family or generic level in Aeolidida are a few and far between. The first molecular phylogeny of the aeolid family Aeolidiidae is presented here. This study, the most comp...

  11. A new phylogeny of the Cephalaspidea (Gastropoda: Heterobranchia) based on expanded taxon sampling and gene markers

    Oskars, Trond Roger; Bouchet, Philippe; Malaquias, Manuel Antonio E.

    2015-01-01

    The Cephalaspidea is a diverse marine clade of euthyneuran gastropods with many groups still known largely from shells or scant anatomical data. The definition of the group and the relationships between members has been hampered by the difficulty of establishing sound synapomorphies, but the advent of molecular phylogenetics is helping to change significantly this situation. Yet, because of limited taxon sampling and few genetic markers employed in previous studies, many questions about the s...

  12. A new phylogeny of the Cephalaspidea (Gastropoda: Heterobranchia) based on expanded taxon sampling and gene markers.

    Oskars, Trond R; Bouchet, Philippe; Malaquias, Manuel António E

    2015-08-01

    The Cephalaspidea is a diverse marine clade of euthyneuran gastropods with many groups still known largely from shells or scant anatomical data. The definition of the group and the relationships between members has been hampered by the difficulty of establishing sound synapomorphies, but the advent of molecular phylogenetics is helping to change significantly this situation. Yet, because of limited taxon sampling and few genetic markers employed in previous studies, many questions about the sister relationships and monophyletic status of several families remained open. In this study 109 species of Cephalaspidea were included covering 100% of traditional family-level diversity (12 families) and 50% of all genera (33 genera). Bayesian and maximum likelihood phylogenetics analyses based on two mitochondrial (COI, 16S rRNA) and two nuclear gene markers (28S rRNA and Histone-3) were used to infer the relationships of Cephalaspidea. The monophyly of the Cephalaspidea was confirmed. The families Cylichnidae, Diaphanidae, Haminoeidae, Philinidae, and Retusidae were found non-monophyletic. This result suggests that the family level taxonomy of the Cephalaspidea warrants a profound revision and several new family and genus names are required to reflect the new phylogenetic hypothesis presented here. We propose a new classification of the Cephalaspidea including five new families (Alacuppidae, Colinatydidae, Colpodaspididae, Mnestiidae, Philinorbidae) and one new genus (Alacuppa). Two family names (Acteocinidae, Laonidae) and two genera (Laona, Philinorbis) are reinstated as valid. An additional lineage with family rank (Philinidae "Clade 4") was unravelled, but no genus and species names are available to reflect the phylogeny and formal description will take place elsewhere. PMID:25916189

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

    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

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

    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.

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

    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

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

    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

  17. The first record of Anisus vorticulus (Troschel, 1834 (Gastropoda: Planorbidae in Croatia?

    Luboš Beran

    2009-12-01

    Full Text Available A threatened planorbid gastropod Anisus vorticulus (Troschel, 1834, listed in the EU Habitat Directive, was found in the Krka National Park in Croatia in August 2009. This find is the first known record at least in the western part of Croatia belonging to the Adriatic Sea drainage area.

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

    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.

  19. Limnaea peregrina Clessin, 1882, Synonym of Lymnaea columella Say, 1817 (Gastropoda: Lymnaeidae

    W Lobato Paraense

    1994-12-01

    Full Text Available A description is given of the shell, radula, renal region, reproductive system and egg capsules of topotypic specimens of limnaea peregrina Clessin, 1882. This investigation intends contributing to define the specific identity of that nominal species. A close anatomical comparison with Lymnaea columella Say, 1817 from Michigan, USA, shows that both forms are indistinguishable, giving support to previous inferences from some authors. Data on egg hatching are presented.

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

    Meire Silva Pena; Norma Campos Salgado; Arnaldo C. dos Santos Coelho

    2011-01-01

    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 i...

  1. A new species of Leiostracus (Gastropoda, Pulmonata, Orthalicoidea from Espírito Santo, Brazil

    Rodrigo B. Salvador

    2014-09-01

    Full Text Available A remarkable new species of pulmonate land snail was found in the collection of the Senckenberg Forschungninstitut und Naturmuseum Frankfurt (Frankfurt am Main, Germany and is described here as Leiostracus faerie sp. nov. It can be easily identified by its small and translucent shell with fine axial light brown bands and its protoconch sculpture. It was collected in the Rio Doce ("Doce River" region in Espírito Santo, Brazil, an area known for a high diversity and endemicity of land snails. This discovery shows how little this fauna is known and reinforces the importance of museum collections in the study of biodiversity and conservation.

  2. Planorbis meridaensis Preston, 1907 (Gastropoda: Planorbidae), a synonym of Biomphalaria prona (Martens, 1873)

    W. Lobato Paraense

    1992-01-01

    Biomphalaria prona from Lake Valencia, Venezuela (type locality) has a polymorphic shell wich in the great majority of specimens is wider, with fewer rapidly expanding whorls, the outer one subcarinate on the left side and more or less strongly deflected leftward. Besides those modal forms there are little frequent variants characterized by narrower shell with less rapidly expanding, regularly curved whorls directed forward. Recent studies have shown that such variants constitute the predomin...

  3. Physa acuta Draparnaud, 1805 (Gastropoda: Physidae): a study of topotypic specimens

    Paraense W Lobato; Pointier Jean-Pierre

    2003-01-01

    A description is given of Physa acuta Draparnaud, 1805, based on topotypic specimens from the Garonne river basin, and additional samples from the environs of the French cities of Montpellier and Perpignan. It proved indistinguishable, in shell and anatomy, from topotypic Physa cubensis Pfeiffer, 1839, thus leading the authors to admit the synonymy of the two nominal species under the older name, P. acuta.

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

    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.

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

    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.

  6. MUDWHELKS (GASTROPODA: POTAMIDIDAE FROM MANGROVES OF UJUNG KULON NATIONAL PARK, BANTEN

    NOVA MUJIONO

    2014-08-01

    Full Text Available A study of Potamididae snail from the mangrove ecosystem in Ujung Kulon National Park was conducted, regarding to its diversity, shell characters and habitat characters. This study was carried out in 2008 during drought and rainy season. At the eight stations observed, seven species and four genera of Potamididae snail were identified. Compared with previous study, this study added new information from obtaining one genus (Cerithidea of three species (Cerithidea weyersi, C. quadrata and Cerithideopsilla alata

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

    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

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

    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

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

    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...

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

    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...

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

    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 ...

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

    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...

  13. Macroevolution of venom apparatus innovations in auger snails (Gastropoda; Conoidea; Terebridae)

    Castelin, M.; Puillandre, N.; Kantor, Y.I.; Modica, M.V.; Terryn, Y.; Cruaud, C.; Bouchet, P.; Holford, M.

    2012-01-01

    The Terebridae are a diverse family of tropical and subtropical marine gastropods that use a complex and modular venom apparatus to produce toxins that capture polychaete and enteropneust preys. The complexity of the terebrid venom apparatus suggests that venom apparatus development in the Terebridae could be linked to the diversification of the group and can be analyzed within a molecular phylogenetic scaffold to better understand terebrid evolution. Presented here is a molecular phylogeny o...

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

    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

  15. Morphological variation, biogeography and local extinction of the northern New Zealand landsnail Placostylus hongii (Gastropoda : Bulimulidae)

    Placostylus hongii (Lesson) is recorded from sites between Whangaroa and Whangarei on the mainland Northland coast, and from the Poor Knights, Chicken, Mokohinau and Great Barrier islands offshore. There is considerable variation in shell morphology between the various populations, commonly with marked morphological divergence at a local scale but with overlapping variation overall across all populations of the taxon. Patterns of morphological variation show no clear geographic trends and are at least in part related to local environmental factors. Correlations are identified between shell shape and substratum type, and between shell size and vegetation type. Placostylus hongii has a very restricted stratigraphic distribution in mainland Northland, with most if not all of the few known fossil populations post-dating Polynesian settlement at c. 900-700 years BP. We suggest that P. hongii populations on the Poor Knights and possibly also those on the Mokohinau islands are endemic, whereas the mainland populations and those on Great Barier and the Chicken islands have originated from anthropic redistribution of snails in prehistoric time. A high proportion of the mainland P. hongii populations and some offshore island populations became extinct in the last few hundred years as a result of predation by introduced mammals and the modification and destruction of shrubland and forest habitat. (author). 54 refs., 9 figs., 1 tab

  16. Organ- and species-specific accumulation of metals in two land snail species (Gastropoda, Pulmonata)

    In order to evaluate the usefulness of terrestrial gastropods as bioindicators there is a need for studies that simultaneously compare (1) concentrations of metals in reference and polluted plots, (2) species within the same polluted habitat, (3) metal accumulation patterns in different organs and (4) metal accumulation patterns in relation to soil physicochemical properties. This study aims to assess metal accumulation patterns in two land snail species. Instead of analyzing an organism as a whole, investigating the partitioning of metals in different organs can provide information on the actual toxicological relevant fractions. Therefore, concentrations of Ag, Cd, Cr, Cu, Ni and Zn were examined in five different organs of Cepaea nemoralis, as well as in the foot and the body of Succinea putris. Snails were sampled at four polluted dredged sediment disposal localities and three adjacent less polluted reference plots situated along waterways in Flanders, Belgium. Due to the small size and problematic dissection of S. putris only the concentrations in the foot of both species could be compared. For this reason only, C. nemoralis can be described as a better bioindicator species that allows a far more detailed analysis of organ metal accumulation. This study showed that organs other than the digestive gland may be involved in the immobilization and detoxification of metals. Furthermore, pH, soil fractionation (clay %, silt %, sand %) and organic matter, correlate with metal accumulation in organs. However, most often the soil metal concentrations did not correlate with the concentrations found in snail organs. Metal concentrations in organs of both species (1) differed among polluted plots but rarely between polluted and reference plots within a locality, (2) were organ-specific (digestive gland > foot > albumen gland = spermoviduct = ovotestis), (3) were species-specific and (4) depended on the metal type (high Cd and Cu concentrations were observed in the digestive gland and foot respectively). Our study emphasizes that background metal levels should be taken into account when using invertebrates as bioindicators of metal contamination and that bioindicators may show substantial differences in accumulation patterns even if they have a highly comparable ecology. - Highlights: ► Concentrations of accumulated metals differ among localities and between the snail species in the foot. ► Organs other than the digestive gland may be involved in the immobilization and detoxification of metals. ► Total metal concentrations and soil physicochemical properties alone are not enough to explain organ bioaccumulation

  17. Report of a human accident caused by Conus regius (Gastropoda, Conidae).

    Haddad, Vidal; Coltro, Marcus; Simone, Luiz Ricardo L

    2009-01-01

    Conus regius is a venomous mollusc in the Conidae family, which includes species responsible for severe or even fatal accidents affecting human beings. This is the first report on a clinical case involving this species. It consisted a puncture in the right hand of a diver who presented paresthesia and movement difficulty in the whole limb. The manifestations disappeared after around twelve hours, without sequelae. PMID:19802483

  18. Venomous mollusks: the risks of human accidents by conus snails (gastropoda: conidae) in Brazil.

    Haddad, Vidal; de Paula Neto, João Batista; Cobo, Válter José

    2006-01-01

    Mollusks of the genus Conus present a venomous apparatus composed of radulae, a chitin structure linked to glands, which injects potent neurotoxic peptides, causing serious human envenomation and even death, associated with the blockage of certain receptors and muscular paralysis. No reported envenomation has occurred in Brazil, but certain populations are at risk of accidents. PMID:17160331

  19. Freshwater snail Pomacea bridgesii (Gastropoda: Ampullariidae, life history traits and aquaculture potential

    Ana R. A. Coelho

    2012-07-01

    Full Text Available Investigations on the reproductive biology, life cycle and feeding habits of Pomacea bridgesiihave been undertaken to assess its potential as a cultured species for the ornamental trade. The speciesis dioecious and, under optimal culture conditions of temperature and food supply, it can breed all yearround. The total developmental period at 23±1ºC varied from 15 to 24 days after oviposition. Hatchingcan last for up to 20 hours in the same egg cluster. Hatching success was very high (mean94.56±0.62% and no significant differences were observed in hatching rates between different clutchsizes. Development is direct and juveniles hatch at shell length (SL = 2.4±0.25 mm. Maturity is reached192±1.5 days after hatching and at SL = 32.80±2.03 mm. Two feeding experiments were undertaken toassess the impact of food type on juvenile survival during the first 8 days post-hatching and subsequentgrowth until 90 days post-hatching. Compatibility between other fish and plants fresh-water aquariumspecies were performed. A combination of environmental tolerance, moderately amphibious behavior,fast growth, short development and hatching at an advanced stage, compatibility with other aquariumspecies (fishes or other invertebrates, and simple low cost diet, make P. bridgesii highly suitable forintensive culture for the ornamental trade.

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

    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.

  1. Periwinkle (Gastropoda: Littorinidae habitat selection and its impact upon microalgal populations

    APOLINÁRIO M.

    1999-01-01

    Full Text Available The present study examines habitat selection and grazing pressure of the periwinkle Nodilittorina lineolata (Gmelin, 1791 on the rocky shore of Arraial do Cabo, RJ, Brazil (lat. 23°S, long. 43°W. Transfer experiments suggest that periwinkles actively select the mid intertidal, where the cirripede Chthamalus bisinuatus Pilsbry is the dominant sessile invertebrate. We also conducted a caging experiment in the middle intertidal, manipulating grazers and light, to assess the impact of grazing upon microalgal density. Grazing pressure significantly reduced microalgal abundance at the mid-intertidal level, suggesting that food availability plays an important role in the habitat selection of periwinkles on the studied shore.

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

    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...

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

    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

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

    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

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

    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

  6. Faecal bacteria in Perna perna (Linnaeus, 1758 (Mollusca: Bivalvia for biomonitoring coastal waters and seafood quality

    Diego Igawa Martinez

    2010-06-01

    Full Text Available Urban development in coastal areas is intense and leads to the increase of sewage outfall and other negative impacts as consequences. Thus, stringent regulations establishing limits to the microbiological contamination of water and seafood are needed. The objective of this study is to evaluate the usefulness of Enterococci and Thermotolerant Coliform densities in the flesh of mussels Perna perna as an alternative tool for monitoring the microbiological quality of coastal waters. The study also considers allometric relations applied to clearance rates to understand rates of bacterial concentration. Bacterial loads obtained in mussels' flesh were from 50 to 4,300 times greater than in the water sampled in the vicinity of the mussels and some were considered inappropriate for consumption even when the water presented no restrictions. The mean clearance rate obtained for Enterococci retention was 317.7 ml h-1 and this rate (CR is related to the mussels' size (L by the equation CR = 28.3229L1.6421. The results showed that bacterial densities in the mussels' tissues may reflect chronic contamination of the environment and that clearance rates are important for taking the best decision in situations where, for example, it is desired to introduce mussels for aquaculture and the evaluation of the water concerned is required.O desenvolvimento urbano em áreas costeiras é intenso e o aumento das descargas de esgoto é uma das conseqüências. Assim, leis específicas que regulem limites para a contaminação microbiológica das águas e de alimentos de origem marinha são necessárias. O objetivo deste estudo é avaliar a utilização de Enterococos e coliformes termotolerantes na carne de mexilhões Perna perna como alternativa para o monitoramento da qualidade microbiológica de águas costeiras. O estudo também considera relações alométricas aplicadas às taxas de "clearance" para entender a concentração de bactérias pelo molusco. As densidades bacterianas obtidas no molusco foram de 50 a 4300 vezes maiores do que nas amostras de água coletadas próximas dos moluscos e alguns foram considerados impróprios para consumo, mesmo quando as águas não mostraram restrições. A taxa de "clearance" média obtida para retenção de Enterococos foi 317.7 ml h-1 e essas taxas (CR puderam ser relacionadas com o tamanho dos mexilhões (L pela equação CR = 28.3229L1.6421. Os resultados mostram que as densidades bacterianas nos tecidos dos mexilhões podem refletir a contaminação crônica do ambiente e que as taxas de "clearance" devem ser consideradas para a tomada de decisão em situações onde, por exemplo, se deseja implantar mexilhões para cultivo.

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

    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.

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

    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.

  9. Biodiversity among luminescent symbionts from squid of the genera Uroteuthis, Loliolus and Euprymna (Mollusca: Cephalopoda)

    GUERRERO-FERREIRA, R. C.; Nishiguchi, M. K.

    2007-01-01

    Luminescent bacteria in the family Vibrionaceae (Bacteria: γ-Proteobacteria) are commonly found in complex, bilobed light organs of sepiolid and loliginid squids. Although morphology of these organs in both families of squid is similar, the species of bacteria that inhabit each host has yet to be verified. We utilized sequences of 16S ribosomal RNA, luciferase α-subunit (luxA) and the glyceraldehyde-3-phosphate dehydrogenase (gapA) genes to determine phylogenetic relationships between 63 stra...

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

    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.

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

    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.

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

    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. 

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

    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

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

    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.

  15. Transcriptomics provides insight into Mytilus galloprovincialis (Mollusca: Bivalvia) mantle function and its role in biomineralisation.

    Bjärnmark, Nadège A; Yarra, T; Churcher, A M; Felix, R C; Clark, M S; Power, D M

    2016-06-01

    The mantle is an organ common to all molluscs and is at the forefront of the biomineralisation process. The present study used the Mediterranean mussel (Mytilus galloprovincialis) as a model species to investigate the structural and functional role of the mantle in shell formation. The transcriptomes of three regions of the mantle edge (umbo to posterior edge) were sequenced using Illumina technology which yielded a total of 61,674,325 reads after adapter trimming and filtering. The raw reads assembled into 179,879 transcripts with an N50 value of 1086bp. A total of 1363 transcripts (321, 223 and 816 in regions 1, 2 and 3, respectively) that differed in abundance in the three mantle regions were identified and putative function was assigned to 54% using BLAST sequence similarity searches (cut-off less than 1e(-10)). Morphological differences detected by histology of the three mantle regions was linked to functional heterogeneity by selecting the top five most abundant Pfam domains in the annotated 1363 differentially abundant transcripts across the three mantle regions. Calcium binding domains dominated region two (middle segment of the mantle edge). Candidate biomineralisation genes were mined and tested by qPCR. This revealed that Flp-like, a penicillin binding protein potentially involved in shell matrix maintenance of the Pacific oyster (Crassostrea gigas), had significantly higher expression in the posterior end of the mantle edge (region one). Our findings are intriguing as they indicate that the mantle edge appears to be a heterogeneous tissue, displaying structural and functional bias. PMID:27037218

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

    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

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

    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.

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

    Araya, Juan Francisco

    2015-01-01

    The bulimulid genus Bostryx Troschel, 1847 is the most species-rich genus of land snails found in Chile, with the majority of its species found only in the northern part of the country, usually in arid coastal zones. This genus has been sparsely studied in Chile and there is little information on their distribution, diversity or ecology. Here, for the first time, a formal analysis of the diversity of bulimulids in the Región de Atacama, northern Chile, is reported. Of the seventeen species recorded for the area, most of them were efectively found in the field collections and one record was based on literature. Five taxa are described as new: Bostryx ancavilorum sp. nov., Bostryx breurei sp. nov., Bostryx calderaensis sp. nov., Bostryx ireneae sp. nov. and Bostryx valdovinosi sp. nov., and the known geographic distribution of seven species is extended. Results reveal that the Región de Atacama is the richest region in terrestrial snails in Chile, after the Juan Fernández Archipelago. All of the terrestrial molluscan species occurring in the area are endemic to Chile, most of them with restricted geographic distributions along the coastal zones, and none of them are currently protected by law. Further sampling in northern Chile will probably reveal more snail species to be discovered and described. PMID:26587346

  19. Hermaphroditism among dioecious Tagelus plebeius (Lightfoot, 1786 (Mollusca, Psammobiidae and Iphigenia brasiliana (Lamarck, 1818 (Mollusca, Donacidae on the Cachoeira River Estuary, Ilhéus, Bahia, Brazil Hermafroditismo nos moluscos dióicos Tagelus plebeius (Lightfoot, 1786 (Mollusca, Psammobiidae e Iphigenia brasiliana (Lamarck, 1818 (Mollusca, Donacidae na região estuarina do Rio Cachoeira, Ilhéus, Bahia, Brasil

    LO. Ceuta

    2010-02-01

    Full Text Available The samples of Tagelus plebeius and Iphigenia brasiliana were manually collected on the Cachoeira River estuary region (Ilhéus, BA, Brazil between August 2005 and August 2006, with a periodicity of 15 days, with 20 animals collected/sampled, performing 500 samples from each species. The animals were measured, eviscerated and kept in solution of Davidson and after 24-30 hours, they were transferred to ethanol 70%. The material was processed for routine histology, with paraffin embedding, obtaining 7 μm thick slices, stained with Harris hematoxilin and Eosin (HE. By light microscopy analysis, 2 cases of hermaphroditism (0.4% in T. plebeius samples and one case (0.2% in I. brasiliana were registered with predominance of female over male follicles.Os exemplares de Tagelus plebeius e Iphigenia brasiliana foram manualmente coletados na região estuarina do Rio Cachoeira (Ilhéus, Bahia, entre agosto de 2005 e agosto de 2006, com coleta quinzenal de 20 animais, totalizando 500 exemplares/espécie. Os animais foram mensurados, eviscerados e fixados em solução de Davidson por 24-30 horas e depois transferidos para etanol a 70%. O material foi processado por técnica rotineira de histologia, com inclusão em parafina, obtenção de cortes com 7 μm de espessura e coloração por hematoxilina de Harris e Eosina (HE. A análise em microscopia de luz evidenciou 2 casos de hermafroditismo (0,4% em T. plebeius e um caso (0,2% em I. brasiliana (0,2%, com predominância de folículos femininos sobre os masculinos.

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

    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

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

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

    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

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

    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

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

    Haszprunar, Gerhard; Friedrich, Stefan; Wanninger, Andreas;

    2002-01-01

    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...

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

    Groenenberg, D.S.J.; Wesselingh, F.P.; Rajagopal, S.; Jansen, J.M.; Bos, M.M.

    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 a depth gradient in the Oosterschelde to a) investigate whether a relation exists between shell shape and depth, b) test if the broad-shelled specimens might represent M. galloprovincialis (or a hy...

  6. On the identity of broad-shelled mussels (mollusca, bivalvia, mytilus) from the Dutch delta region

    Groenenberg, D.S.J.; Wesselingh, F.P.; Rajagopal, S.; Jansen, J.M.; Bos, M.M.; Van De Velde, 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 a depth gradient in the Oosterschelde to a) investigate whether a relation exists between shell shape and depth, b) test if the broadshelled specimens might represent M. galloprovincialis (or a hyb...

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

    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.

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

    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.

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

    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...

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

    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.

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

    Avila, Sérgio P; Sigwart, Julia

    2013-01-01

    Published records, original data from recent field work on all of the islands of the Azores (NE Atlantic), and a revision of the entire mollusc collection deposited in the Department of Biology of the University of the Azores (DBUA) were used to compile a checklist of the shallow-water Polyplacophora of the Azores. Lepidochitona cf. canariensis and Tonicella rubra are reported for the first time for this archipelago, increasing the recorded Azorean fauna to seven species. PMID:23825446

  12. Chiton integument: ultrastructure of the sensory hairs of Mopalia muscosa (Mollusca: Polyplacophora).

    Leise, E M; Cloney, R A

    1982-01-01

    The dorsal integument of the girdle of the chiton Mopalia muscosa is covered by a chitinous cuticle about 0.1 mm in thickness. Within the cuticle are fusiform spicules composed of a central mass of pigment granules surrounded by a layer of calcium carbonate crystals. Tapered, curved chitinous hairs with a groove on the mesial surface pass through the cuticle and protrude above the surface. The spicules are produced by specialized groups of epidermal cells called spiniferous papillae and the hairs are produced by trichogenous papillae. Processes of pigment cells containing green granules are scattered among the cells of each type of papilla and among the common epidermal cells. The wall or cortex of each hair is composed of two layers. The cortex surrounds a central medulla that contains matrix material of low density and from 1 to 20 axial bundles of dendrites. The number of bundles within the medulla varies with the size of the hair. Each bundle contains from 1 to 25 dendrites ensheathed by processes of supporting cells. The dendrites and supporting sheath arise from epidermal cells of the central part of the papilla. At the base of each trichogenous papilla are several nerves that pass into the dermis. Two questions remain unresolved. The function of the hairs is unknown, and we have not determined whether the sensory cells are primary sensory neurons or secondary sensory cells. PMID:7066970

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

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

    2005-08-01

    The major lateral teeth of the chiton Acanthopleura echinata are composite structures composed of three distinct mineral zones: a posterior layer of magnetite; a thin band of lepidocrocite just anterior to this; and apatite throughout the core and anterior regions of the cusp. Biomineralization in these teeth is a matrix-mediated process, in which the minerals are deposited around fibers, with the different biominerals described as occupying architecturally discrete compartments. In this study, a range of scanning electron microscopes was utilized to undertake a detailed in situ investigation of the fine structure of the major lateral teeth. The arrangement of the organic and biomineral components of the tooth is similar throughout the three zones, having no discrete borders between them, and with crystallites of each mineral phase extending into the adjacent mineral zone. Along the posterior surface of the tooth, the organic fibers are arranged in a series of fine parallel lines, but just within the periphery their appearance takes on a "fish scale"-like pattern, reflective of the cross section of a series of units that are overlaid, and offset from each other, in adjacent rows. The units are approximately 2 microm wide and 0.6 microm thick and comprise biomineral plates separated by organic fibers. Two types of subunits make up each "fish scale": one is elongate and curved and forms a trough, in which the other, rod-like unit, is nestled. Adjacent rod and trough units are aligned into large sheets that define the fracture plane of the tooth. The alignment of the plates of rod-trough units is complex and exhibits extreme spatial variation within the tooth cusp. Close to the posterior surface the plates are essentially horizontal and lie in a lateromedial plane, while anteriorly they are almost vertical and lie in the posteroanterior plane. An understanding of the fine structure of the mineralized teeth of chitons, and of the relationship between the organic and mineral components, provides a new insight into biomineralization mechanisms and controls. PMID:15959908

  14. [Polyplacophoran communities (Mollusca: Polyplacophora) at Bahia de La Paz, Baja California Sur, México].

    García Ríos, Cedar I; Alvarez Ruiz, Migdalia

    2007-03-01

    Eight species of polyplacophorans have been reported from La Bahia de la Paz, Baja California Sur, Mexico. We add Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata and Acanthochitona arragonites, increasing the known number of species to 15. Ordination analysis of five chiton communities at the site suggests a correlation of wave exposure to species composition and diversity: communities with intermediate wave exposure have more species (richness) and higher diversity (Shannon's index). PMID:18457125

  15. The continuing debate on deep molluscan phylogeny: evidence for Serialia (Mollusca, Monoplacophora + Polyplacophora).

    Stöger, I; Sigwart, J D; Kano, Y; Knebelsberger, T; Marshall, B A; Schwabe, E; Schrödl, M

    2013-01-01

    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. PMID:24350268

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

    Haszprunar, Gerhard; Friedrich, Stefan; Wanninger, Andreas; Ruthensteiner, Bernhard

    2002-02-01

    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 symmetrically situated pairs lying dorsolaterally and ventrolaterally in the pretrochal part of the trochophore-like larva and they send axons into the cerebral commissure. They are lost at metamorphosis. The fine structure of these cells strongly resembles that of so-called "ampullary cells" known from various 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. PMID:11748704

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

    Orlando Guerra Júnior

    1983-12-01

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

  18. Reproductive Features of Indigenous and the Invasive Chinese Freshwater Mussels (Mollusca, Bivalvia, Anodontinae in Ukraine

    Yanovych L. M.

    2015-10-01

    Full Text Available Процессы размножения аборигенных видов беззубок из водоемов и водотоков Украины протекают неполноценно. Среди Anodonta anatinа (Linnaeus, 1758 примерно только в 60 % пунктов сбора размножаются 100 % самок, в остальных пунктах «беременными» оказываются лишь 17-90 % самок, у A. cygnea (Linnaeus, 1758 - 50 % самок. Примерно в 70 % пунктов сбора самки A. cygnea и Pseudanodonta complanata Rossmassler, 1835 имеют не полностью (от . до . заполненные половыми продуктами марсупии. Зато вид-вселенец китайская беззубка, Sinanodonta woodiana (Lea, 1834, имеет многократные кладки в течение всего года. Полужабры половыми продуктами заполнены полностью.

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

    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.)

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

    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

  1. Verspreiding en habitats van Ceratophallus natalensis (Mollusca: Planorbidae in Suid-Afrika

    K. N. de Kock

    2007-09-01

    Full Text Available Hierdie artikel handel oor die geografiese verspreiding en habitats van Ceratophallus natalensis soos weerspieël deur die 1 797 monsters wat tans in die databasis van die Nasionale Varswater- slakversameling (NVWSV opgeneem is. Hierdie spesie is in al 14 verskillende waterliggaamtipes wat in die databasis verteenwoordig word, aangetref. Die grootste getal monsters was afkomstig van damme, spruite en riviere. Habitats met standhoudende, stilstaande en varswater waarvan die substratum oorwegend uit modder bestaan het, was die beste verteenwoordig. Die resultate van ’n geïntegreerde besluitnemingsboom- en effekgrootte-analise het getoon dat temperatuur, hoogte bo seevlak en waterliggame as sodanig, ’n deurslaggewende rol in die gedokumenteerde geografiese verspreiding van hierdie spesie in Suid-Afrika gespeel het. ’n Temperatuurindeks wat bereken is, het getoon dat C. natalensis ook goed toegerus is om habitats in die koeler streke van Suid-Afrika te bevolk. Gesien in die lig van die wye geografiese verspreiding van hierdie spesie in hierdie land en dat dit elders in Afrika bevind is dat dit serkarieë van verskeie helmintspesies onder natuurlike toestande kan vrystel, word dit aanbeveel dat sy rol as tussengasheer in Suid-Afrika deeglik ondersoek behoort te word.

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

    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

  3. Mollusca from Preangerian deposits of Mandul Island, northeastern Kalimantan Timur (East Borneo)

    Beets, C.

    1984-01-01

    The present paper gives the result of work on a collection of molluscs which was made in 1916 by W. H. van Hoist Pellekaan on behalf of the Bataafsche Petroleum Maatschappij, now Shell Internationale Petroleum Maatschappij. A preliminary examination of the fossils was made by K. Martin, also in 1916, his conclusion, based on 22 species, being that their age was either 'uppermost Old Miocene' (i.e., Njalindung) or 'Upper Miocene'. According to modern usage, this would imply a dating of the fau...

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

    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.

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

    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.

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

    Sérgio Ávila

    2013-06-01

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

  7. Temporal dynamics of amino and fatty acid composition in the razor clam Ensis siliqua (Mollusca: Bivalvia)

    Baptista, Miguel; Repolho, Tiago; Maulvault, Ana Luísa; Lopes, Vanessa M.; Narciso, Luis; Marques, António; Bandarra, Narcisa; Rosa, Rui

    2014-12-01

    Few studies have been conducted on the temporal dynamics of both amino acid (AA) and fatty acid (FA) profiles in marine bivalves. We investigated the seasonal variation of these compounds in the pod razor clam Ensis siliqua in relation to food availability, salinity, water temperature and reproductive cycle. AA content varied between 46.94 and 54.67 % dry weight (DW), and the AAs found in greater quantity were glutamic acid, glycine and aspartic acid. FA content varied between 34.02 and 87.94 mg g-1 DW and the FAs found in greater quantity were 16:0 and 22:6 n-3. Seasonal trends were observed for AAs and FAs. FAs increased with gametogenesis and decreased with spawning while AA content increased throughout spawning. The effect of increasing temperature and high food availability during the spawning season masked the loss of AAs resulting from gamete release. Still, a comparatively greater increase in the contents of glutamic acid and leucine with spawning indicate their possible involvement in a post-spawning gonad recovery mechanism. A post-spawning decrease in 14:0, 16:0, 16:1 n-7, 18:1 n-7 and 18:1 n-9 is indicative of the importance of these FAs in bivalve eggs. An increase in 18:3 n-3, 18:4 n-3, 20:1 n-9 and 20:2 n-6 during gametogenesis suggests their involvement in oocyte maturation. The FA 22:4 n-6, while increasing with spawning, appears to play a role in post-spawning gonad recovery. Salinity did not have an effect on the AA composition. None of the environmental parameters measured had an effect on FA composition.

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

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

  9. Multi-species generalist predation on the stochastic harvested clam Tivela mactroides (Mollusca, Bivalvia)

    Turra, Alexander; Fernandez, Wellington S.; Bessa, Eduardo; Santos, Flavia B.; Denadai, Márcia R.

    2015-12-01

    Top-down control is an important force modulating the abundance of prey and structuring marine communities. The harvested trigonal clam Tivela mactroides is hypothesized to be part of the diet of a variety of marine organisms, with its stock influencing predator abundance and being influenced by them. Here we analyzed the diet of potential predators of T. mactroides in Caraguatatuba Bay, northern coast of São Paulo State, Brazil, to identify the main consumers of this marine resource, and also to address the importance of this clam in the diet of each predator. Samples were taken year-round by trawls; all specimens collected were identified and measured and the food items identified and quantified. Twenty-one species consumed T. mactroides, whose importance in the diet varied greatly in both the volume ingested and the frequency of occurrence (pompano Trachinotus carolinus > blue crab Callinectes danae > starfish Astropecten marginatus). Top-down influence on T. mactroides was also dependent on the abundance of consumers (yellow catfish Cathorops spixii > rake stardrum Stellifer rastrifer > barred grunt Conodon nobilis > A. marginatus). Considering the mean volume ingested, the frequency of occurrence of T. mactroides in the diet, and the relative abundance of consumers, the predators that most influenced T. mactroides were T. carolinus, A. marginatus, and C. danae, in decreasing order. Large numbers of small-sized individuals of T. mactroides (<10 mm) were generally preyed upon by A. marginatus, which may have a stronger effect on clam abundance in comparison to C. danae and T. carolinus, which preyed upon larger clams. In conclusion, the results of this study indicate that predators' consumption of T. mactroides in Caraguatatuba Bay can influence its stocks, mainly due to the type and/or abundance of predator species, the volume and number of individuals of T. mactroides preyed upon, and the temporal variations in the abundance of predators.

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

    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.

  11. Random walk, zonation and the food searching strategy of Terebralia palustris (Mollusca, Potamididae) in Kenya

    Vannini, Marco; Cannicci, Stefano; Mrabu, Elisha; Rorandelli, Rocco; Fratini, Sara

    2008-12-01

    Terebralia palustris is a common mud-whelk present at a particularly high density in all Indo-West Pacific mangroves. Young snails feed on nothing but mud while larger specimens are able to feed on fallen leaves too. In Kenya (Mida Creek) under the canopy, competition for mangrove leaves can be very high due to the high density of Sesarmidae crabs. On open exposed muddy platforms, no Sesarmidae occur but the leaf density is very low because the leaves are only randomly present as they are deposited and removed twice a day by the tide. However, the snail density is always very high, raising the question as to whether the snails use a special searching strategy to optimize their resource finding rather than a purely random movement. By analyzing the snails' movements on a uniform area at different levels and comparing them with simulated random paths, we could show that the snails' movements are not purely random. The distribution of different size classes of T. palustris in Mida Creek was known to be quite odd: the same simulation approach suggests that the zonation asymmetry could reasonably be due to the stochastic recruitment of juveniles in space and time and maintained by a substantial long-lasting spatial inertia.

  12. Members of the genus Pisidium C. Pfeiffer (Mollusca: Bivalvia) of the Czech Republic

    Currently, thirteen species assigned to the genus Pisidium are known from the territory of the Czech Republic. This paper contains a new key to them with original figures of definitive characteristics. The key is supplemented with species descriptions and notes on their ecology and distribution in the Czech Republic. Differences between conchologically similar species and possibilities of misidentification with juvenile specimens of the genera Sphaerium and Musculium are commented on as well. (authors)

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

    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 (<7 cm ML) in the samples, which might indicate that these individuals inhabit rocky grounds that are not accessible to trawlers or waters deeper than the maximum depth sampled (800 m). The species occurred more frequently around the Balearic Islands than along the Iberian Peninsula as they appeared in 20% and 7%, respectively, of the hauls in these areas. The 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.

  14. Spawning, fertilization, and larval development of Potamocorbula amurensis (Mollusca: Bivalvia) from San Francisco Bay, California

    Nicolini, M.H.; Penry, D.L.

    2000-01-01

    In Potamocorbula amurensis time for development to the straight-hinge larval stage is 48 hr at 15??C. Potamocorbula amurensis settles at a shell length of approximately 135 ??m 17 to 19 days after fertilization. Our observations of timing of larval devdlopment in P. amurensis support the hypothesis of earlier workers that its route of initial introduction to San Francisco Bay was as veliger larvae transported in ballast water by trans-Pacific cargo ships. The length of the larval period of P. amurensis relative to water mass residence times in San Francisco Bay suggests that it is sufficient to allow substantial dispersal from North Bay to South Bay populations in concordance with previous observations that genetic differentiation among populations of P. amurensis in San Francisco Bay is low. Potamocorbula amurensis is markedly euryhaline at all stages of development. Spawning and fertilization can occur at salinities from 5 to 25 psu, and eggs and sperms can each tolerance at least a 10-psu step increase or decrease in salinity. Embryos that are 2 hr old can tolerate the same range of salinities from (10 to 30 psu), and by the time they are 24 hr old they can tolerate the same range of salinities (2 to 30 psu) that adult clams can. The ability of P. amurensis larvae to tolerate substantial step changes in salinity suggests a strong potential to survive incomplete oceanic exchanges of ballast water and subsequent discharge into receiving waters across a broad range of salinities.

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

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

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

    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.

  17. Three new species of Pruvotinidae (Mollusca: Solenogastres) from Antarctica and NW Spain

    Zamarro, Maria; García-Álvarez, Oscar; Urgorri, Victoriano

    2013-09-01

    The family Pruvotinidae (Solenogastres, Cavibelonia) includes thirty species of fifteen genera grouped in five subfamilies. These subfamilies are defined by the combination of the presence or absence of hollow hook-shaped sclerites, the presence or absence of a dorsopharyngeal gland and the type of ventrolateral foregut glandular organs: type A, type C or circumpharyngeal. In this paper, three new species of the family Pruvotinidae are described: Pruvotina artabra n. sp. and Gephyroherpia impar n. sp. from NW Spain, and Pruvotina manifesta n. sp. from Antarctic Peninsula. These new descriptions increase the global knowledge of Solenogastres biodiversity.

  18. Freshwater bivalve mollusca (unionidae, sphaeriidae, corbiculidae) of the Savannah River Plant, South Carolina

    A guide to freshwater bivalve molluscs found at the Savannah River Plant is presented. A dichotomous taxonomic key is provided to common forms and to unreported species whose geographic distributions include nearby localities. Discussions of ecology, life history, larval hosts, and other pertinent information is provided

  19. Ultrastructure developments during spermiogenesis in Polydora ciliata (Annelida: Spionidae), a parasite of mollusca

    Gao, Yan; Zhang, Tao; Zhang, Libin; Qiu, Tianlong; Xue, Dongxiu; Yang, Hongsheng

    2014-12-01

    Spionid worms of Polydora ciliata inhabit the shells of many commercially important bivalves and cause disease in molluscan aquaculture. Their sperm structure is closely related to their fertilization method. To give an insight into the sperm structure and spermatogenesis, ultrastructure details of the subcellular components of germ cells during spermiogenesis of Polydora ciliata are detected by transmission electron microscopy (TEM). In P. ciliata, during spermiogenesis, chromatin is regularly arranged as dense fibrils and becomes more condensed when the nucleus elongates. Microtubules do not surround the nucleus during its elongation. The Golgi phase is characterized by the formation of proacrosomal granules within the Golgi apparatus. The proacrosomal granules fuse to form a single, spherical acrosomal vesicle that migrates to the anterior pole of the cell. At the time of nuclear condensation, mitochondria become reduced in number but increased in size, causing deep indentation at the base of the nucleus. The mid-piece has a few mitochondria. The cap phase includes the spreading of the acrosomal granule over the surface of the nucleus of the differentiating spermatid. The acrosomal phase of spermiogenesis is typically associated with changes in the shape of the nucleus, acrosome and tail. The relationship of sperm ultrastructure to spermiogenesis in spionidae species was discussed.

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

    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 (<120 cm shell length) endemic to the Mediterranean that lives one-third buried in soft substrata, generally in shallow coastal waters. We hypothesised that P. nobilis of different sizes would ingest different food sources, because small fan shells will inhale material from closer to the substratum than do large fan shells. We studied stomach contents and faeces of 18 fan shells, 6 small (mean 23.0 cm length), 6 medium-sized (mean 41.5 cm length) and 6 large (mean 62.7 cm length) living in a small area of a low-energy coastal detritic bottom characterised by mud, sand and macroalgae at Mali Ston Bay, Croatia. We found that all P. nobilis ingested copious quantities of undetermined detritus (probably at least 95% of ingested material), phytoplankton, micro and mesozooplankton and pollen grains. Large P. nobilis stomach contents showed a preponderance of water column calanoid copepods, while small fan shells had higher numbers of bivalve larvae. All fan shells took in high numbers of harpacticoid copepods that are benthonic, feeding on microbial communities of detritus and benthic vegetation. There was also a significant selection of phytoplankton species, some apparently occurring between inhalation and ingestion. The stomach contents of small P. nobilis had a higher organic matter content than either medium-sized or large fan shells; this indicated that small fan shells ingested detritus of higher organic content than did larger P. nobilis. As the faeces of all P. nobilis had similar organic matter content, this also indicates higher assimilation efficiencies in small fan shells. The demonstration of differential dietary selectivity by different sized 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.

  1. Evaluation of Freshwater Mussel (Mollusca: Unionoidea) Fitness Pre- and Post- Relocation Efforts

    McIntyre, H. E.; Farris, J. L.; Christian, A. D.

    2005-05-01

    Freshwater mussels are often displaced by human activities. Construction of bridges that offer potential impact to large numbers mussels often results in a relocation strategy to minimize loss. While this may reduce mortality, the metabolic consequences of relocation have not been evaluated. In this study we measured glycogen and lipid concentrations and RNA to DNA ratios to determine fitness impairments on relocated mussels. We hypothesize that organisms subjected to continuous stress should first use stored glycogen, followed by growth cessation measured as a reduction of RNA in relation to the DNA present, and finally a mobilization of tissue lipids, measured as a decrease in tissue lipid concentrations. We collected mantle snips from three surrogate species of mussels from four sites on the White River in eastern Arkansas during late summer, to establish expected glycogen, lipid, and RNA:DNA levels. Mean tissue lipids concentrations (μg/g) were 63.09, 67.96, and 50.46 for Quadrula quadrula, Q. pustulosa and Obliquaria reflexa, respectively. Mean tissue glycogen concentrations (μg/g) were 346.66, 592.26, and 336.58 for Q. quadrula, Q. pustulosa, and O. reflexa, respectively. This study can provide response information on relocated individuals as well as provide estimation of sufficient time required for mussel adaptation to novel environments.

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

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

    2016-05-01

    We present the complete mitochondrial genome of the Achatina fulica in this study. The results show that the mitochondrial genome is 15,057 bp in length, which is comprised of 13 protein-coding genes, 2 rRNA genes, 21 tRNA genes. The nucleotide compositions of the light strand are 35.47% of A, 27.97% of T 19.46% of C, and 17.10% of G. Except the ND3, 7 tRNA, ATP6, ATP8, COX3 and 12S-rRNA on the light strand, the rest are encoded on the heavy strand. Five types of inferred initiation codons are ATA (ND1, ND5), GTG (ND6), ATG (COX3, COX2), ATT (ND4) and TTG (COX1, ND2, ND3, ND4L, ATP6, ATP8, Cytb), and 3 types of inferred termination codons are T (COX3, ND2), TAA (ND1, ND4L, ND5, ND6, ATP6), and TAG (ND3, ND4, COX1, COX2, Cytb, ATP8). There are 24 intergenic spacers and 6 gene overlaps. The tandem repeat sequence (total 52 bp) of (AATAATT)n is observed in 16S-rRNA. Gene arrangement and distribution are inconsistent with the typical vertebrates. PMID:25231719

  3. Submarine canyons as the preferred habitat for wood-boring species of Xylophaga (Mollusca, Bivalvia)

    Romano, C.; Voight, J. R.; Company, J. B.; Plyuscheva, M.; Martin, D.

    2013-11-01

    Submarine canyons are often viewed as natural “debris concentrators” on the seafloor. Organic substrates may be more abundant inside than outside canyon walls. To determine the effects of the presence these substrates in the Blanes submarine canyon (NW Mediterranean) and its adjacent western open slope, we deployed wood to study colonizing organisms. Three replicate pine and oak cubes (i.e. most common trees inland) were moored at 900, 1200, 1500 and 1800 m depth and collected after 3, 9 and 12 months. Wood from inside the canyon was significantly more heavily colonized by the five morphotypes of wood-boring bivalves than was wood on the adjacent open slope. Xylophaga sp. A dominated all wood types and locations, with peak abundance at 900 and 1200 m depth. Its growth rate was highest (0.070 mm d-1) during the first three months and was faster (or it recruits earlier) in pine than in oak. Size distribution showed that several recruitment events may have occurred from summer to winter. Xylophaga sp. B, appeared first after 9 months and clearly preferred pine over oak. As the immersion time was the same, this strongly supported a specific association between recruiters and type of substrate. Three morphotypes, pooled as Xylophaga spp. C, were rare and seemed to colonize preferentially oak inside the canyon and pine in the adjacent open slope. Individuals of Xylophaga were more abundant inside the canyon than in nearby off-canyon locations. Blanes Canyon may serve as a long-term concentrator of land-derived vegetal fragments and as a consequence sustain more animals. Are the species richness and abundance of wood-boring bivalves higher inside the canyon than on the adjacent open slope? Do the composition and density of the wood-boring bivalves change with deployment time and depth, as well as on the type of the sunken wood? What is the growth rate of the dominant wood-boring species?

  4. Ultrastructure of euspermatozoa and paraspermatozoa in the volutid snail Adelomelon ancilla (Mollusca: Caenogastropoda)

    Zabala, S.; Hermida, G. N.; Giménez, J.

    2009-09-01

    The ultrastructure of the euspermatozoa and the paraspermatozoa is investigated in Adelomelon ancilla, through histological section observed by transmission electron microscopy. Euspermatozoa of A. ancilla consists of: (1) a conical acrosomal vesicle (with a short basal invagination, constricted anteriorly) which is flattened at the apex and associated with an axial rod, a centrally perforated basal plate and a short accessory membrane, (2) a rod-shaped, solid and highly electron-dense nucleus (with a short basal fossa containing a centriolar complex and a initial portion of a 9 + 2 axoneme), (3) an elongate midpiece consisting of the axoneme sheathed by 5-6 helical mitochondrial elements each exhibiting a dense U-shaped outer layer, (4) an elongate glycogen piece (where the axoneme is sheathed by nine tracts of glycogen granules), (5) a dense annulus at the junction of the midpiece and glycogen piece, and (6) a short free tail region (where the axoneme is surrounded only by plasma membrane). We observed a parasperm in A. ancilla. This is vermiform in shape and is composed of multiple axonemes and extensive cytoplasm with numerous vesicles, and mitochondria are scattered inside the axonemes. Sperm of A. ancilla is characterized by the euspermatozoa type 2 and the paraspermatozoa morphology belongs to type 5. The U shaped electrodense mitochondrial element in the midpiece of the eusperm and the constriction in the acrosomal vesicle present in A. ancilla are exclusive. We suggest that these characteristics could have taxonomic importance, because these was observed in other volutids and have not been observed in the rest of caenogastropods studies. We consider that the morphology of paraspermatozoa in A. ancilla corresponds to the “lancet” type.

  5. The end of a long controversy: systematics of the genus Limenandra (Mollusca: Nudibranchia: Aeolidiidae)

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

    2014-03-01

    Limenandra Haefelfinger and Stamm 1958 is a small genus within the Aeolidiidae with, until this paper, only two species: Limenandra nodosa Haefelfinger and Stamm 1958 and Limenandra fusiformis Baba 1949. Although most recent authors have regarded Limenandra as a junior synonym of Baeolidia Bergh 1888, recent molecular studies have demonstrated its monophyletic status and have rejected the circumtropical distribution attributed to the type species, L. nodosa. The present paper reviews the previously known species of Limenandra with additional morphological data and describes three new species: Limenandra barnosii sp. nov. and Limenandra rosanae sp. nov. from the Indo-Pacific are easily distinguished from all other Limenandra species by their vivid and bright colour patterns, while Limenandra confusa sp. nov., also from the Indo-Pacific, is very similar to the Atlantic and Mediterranean L. nodosa. The five species differ in colouration, the size and ornamentation of the cerata, the rhinophorial papillae, details of the reproductive system and the number of salivary glands. Additionally, Limenandra can be easily distinguished from other Aeolidiidae based on differences in the radular and receptaculum seminis morphology.

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

    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. PMID:26427825

  7. Recovery of the biogenic nest habitat of Limaria hians (Mollusca: Limacea) following anthropogenic disturbance

    Trigg, Colin; Moore, Colin G.

    2009-04-01

    The rate of regrowth of Limaria hians nest material, following a simulated dredging impact, was examined on an extensive L. hians bed off the west coast of Scotland. Within an area of complete coverage of the sea bed by a turf of L. hians nest material, the turf was cleared by diver from 10 × 0.25 m 2 plots and the sediment subsequently raked to simulate the passage of a scallop dredge. The areal extent and pattern of nest regrowth were recorded after 6 and 12 months. Control plots showed no significant change in 100% nest cover over the year. In the treated plots regrowth generally occurred from extension of peripheral nest material. Over the initial 6 autumn and winter months treatment plots displayed a mean regrowth of 9.2% of the cleared area, increasing to 15% in the second 6-month spring and summer period. However, no significant difference in growth was found between these periods. After 12 months half the treatment plots exhibited <25% nest cover and none of them contained nest of a thickness comparable to the surrounding bed. Conversion of regrowth rates within the treated plots to the rate of nest advance along a linear front, gave a value of 3.2 cm per year, highlighting the susceptibility of this species-rich biotope to scallop dredging.

  8. Epibiotic relationships on Zygochlamys patagonica (Mollusca, Bivalvia, Pectinidae) increase biodiversity in a submarine canyon in Argentina

    Schejter, Laura; López Gappa, Juan; Bremec, Claudia Silvia

    2014-06-01

    The continental slope of the southern SW Atlantic Ocean has many distinguishable deep submarine canyons, varying in depth and extension. The benthic fauna within one of them, detected in April 2005 by means of a multibeam SIMRAD EM1002 sonar, and located at 43°35‧S to 59°33‧W, 325 m depth, was studied to discuss faunal affinities with the neighbouring Patagonian scallop fishing grounds located at upper slope depths. In order to add faunal information to the previous general study, we studied the epibiotic species settled on Patagonian scallops (the dominant species in the area) collected in the reference sampling site using a 2.5-m mouth-opening dredge, 10 mm mesh size. We sampled 103 scallops with shell heights between 22 and 69 mm; epibionts were recorded on both valves. We found 53 epibiotic taxa, which were most conspicuous on the upper valve. Bryozoa was the most diverse group (34 species) while Polychaeta was the most abundant group, recorded on 94% of the scallops. Stylasteridae (2 species) and Clavulariidae (Cnidaria) conform newly recorded epibionts on Z. patagonica and the sponge Tedania (Tedaniopsis) infundibuliformis also represents a new record for the SW Atlantic Ocean.

  9. External morphology of spermatozoa and spermatozeugmata of the freshwater mussel Truncilla truncata (Mollusca: Bivalvia: Unionidae)

    Waller, D.L.; Lasee, B.A.

    1997-01-01

    Truncilla truncata males release spherical aggregates of spermatozoa, called spermatozeugmata, at spawning. Sperm aggregates from other bivalve species have been described, but few detailed studies exist of the morphology of unionid spermatozeugmata and spermatozoa. We provide the first description of the external morphology of spermatozeugmata and spermatozoa of T. Truncata. The spermatozeugmata had an inside diameter of 76 mu m and contained 8000-9000 spermatozoa. Heads of spermatozoa were directed toward the center of the sphere into a translucent shell; tails were arranged radially and caused the spermatozeugmata to rotate. Spermatozoa of T. Truncata measured 3.3 mu m in length (excluding tail) and each had a head, a midpiece and a flagellum. We also documented the release of spermatozeugmata in two additional unionid species, Lampsilis cardium and Amblema plicata plicata.

  10. Spermatozoa and spermatogenesis in the northern quahaug Mercenaria mercenaria (Mollusca, Bivalvia)

    Ying, Xue-Ping; Yang, Wan-Xi; Dahms, Hans-U.; Lin, Zhihua; Chai, Xueliang

    2008-12-01

    We studied the ultrastructure of spermatogenesis and spermatozoa in the northern quahaug, the clam Mercenaria mercenaria. Spermatogenetic cells gradually elongate. Mitochondria gradually fuse and increase in size and electron density. During spermatid differentiation, proacrosomal vesicles migrate towards the presumptive anterior pole of the nucleus and eventually form the acrosome. The spermatozoon of M. mercenaria is of a primitive type. It is composed of head, mid-piece, and tail. The acrosome shows a subacrosomal space with a short conical contour. The slightly curved nucleus of the spermatozoon contains fine-grained dense chromatin. The middle piece consists of a centriolar complex which is surrounded by four mitochondria. The flagellum has a standard “9 + 2” microtubular structure. The ultrastructure of spermatozoa and spermatogenesis of M. mercenaria shares a number of features with other species of the family Veneridae. M. mercenaria may be a suitable model species for further investigations into the mechanisms of spermatogenesis in the Bivalvia.

  11. Novas ocorrências de gastrópodes e bivalves marinhos no Brasil (Mollusca

    Absalão Ricardo Silva

    2003-01-01

    Full Text Available The gastropods Costaclis egregia (Dall, 1889, Thaleia nisonis (Dall, 1889, Tjaernoeia michaeli Engl, 2001 and the bivalves Bathyarca sp., Myonera aff. ruginosa (Jeffreys, 1882 are recorded for the first time in Brazilian waters. This paper presents a brief description of these species and also include ilustrations.

  12. Body condition and gametogenic cycle of Galatea paradoxa (Mollusca: Bivalvia) in the Volta River estuary, Ghana

    Adjei-Boateng, D.; Wilson, J. G.

    2013-11-01

    The reproductive cycle of Galatea paradoxa which is the basis for an artisanal fishery in the Volta River estuary, Ghana, was studied using condition indices and histological methods from March 2008 to July 2009. The cycle is annual with a single spawning event between June and October. Gametogenesis starts in November progressing steadily to a peak in June-July when spawning begins until October when the animal is spent. The condition indices (shell-free wet weight/total wet weight, ash-free dry weight/shell weight and gonad wet weight/shell weight) showed a clear relationship with the gametogenic stage rising from a minimum at stage (I) start of gametogenesis, to their highest values at stages (IIIA) ripe and (IIIB) start of spawning before declining significantly to stage (IV) spent.It is suggested that condition index may prove a valuable technique in fishery management to recognise the reproductive stages of G. paradoxa as it is less expensive and time consuming than histological techniques in addition to being easier to teach to non-specialists. The data presented in this study provide information on the timing of spawning events for G. paradoxa, which is necessary for developing sustainable management strategies and selection of broodstock for aquaculture.

  13. Morfologia y biologia de Bostryx conspersus (Sowerby) (Mollusca, Bulimulidae) en las lomas costeras del Peru Central

    Rina Ramírez

    1988-01-01

    Morphological and biological observations on populations of the land snail Bostryx conspersus, in three "Lomas"of the Central Coast of Peru, were carried out between 1979 and 1982. Three shell color varieties of B. conspersus are reponed herein, as well as its aestivation, activity and reproduction strategies. The possible interactions of B. conspersus with a dipteron (Scaptomyza sp.; Drosophilidae) and a nematode species are also discussed.

  14. Brazilian species of Gadila (Mollusca: Scaphopoda: Gadilidae): rediscovery of Gadila elongata comb. nov. and shell morphometrics

    Carlos H. S. Caetano; Victor Scarabino; Ricardo S. Absalão

    2010-01-01

    Gadila elongata comb. nov. was described in 1920 from the northern Gulf of Mexico. Until recently, it was only known from the type locality. Herein we present the first record of G. elongata from Brazil (Northeast coast, Ceará state, collected at 177 m) and a morphometrics analysis of the Brazilian species of Gadila. A multivariate Discriminant Function Analysis, based on nine shell morphometric variables (length, maximum diameter, length to maximum diameter ratio, distance of point of maximu...

  15. Contribuição ao conhecimento de Thais mariae, Morretes, 1954 (Mollusca prosobranchia)

    Antonio Carlos Marini

    1988-01-01

    São feitos estudos sobre a morfologia da concha, pênis, rádula, opérculo e cápsula de desova de Thais mariae Morretes, em comparação com T. haemastoma (Linnaeus).Studies are made on the shell, penis, radula, operculum and eggshell case of Thais mariae Morretes, compared with T. haemastoma (Linnaeus).

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

    Sonia Barbosa dos Santos

    1989-01-01

    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 widt...

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

    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.

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

    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.

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

    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...

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

    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

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

    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.

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

    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.

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

    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.

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

    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.

  5. The Gastropods of Lake Eğirdir

    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 ...

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

    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

  7. Evolution of gastropod mitochondrial genome arrangements

    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.

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

    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

  9. Benthic macroinvertebrates in Italian rice fields

    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.

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

    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.

  11. Fine morphology of the jaw apparatus of Puncturella noachina (Fissurellidae, Vetigastropoda).

    Vortsepneva, Elena; Ivanov, Dmitry; Purschke, Günter; Tzetlin, Alexander

    2014-07-01

    Jaws of various kinds occur in virtually all groups of Mollusca, except for Polyplacophora and Bivalvia. Molluscan jaws are formed by the buccal epithelium and either constitute a single plate, a paired formation or a serial structure. Buccal ectodermal structures in gastropods are rather different. They can be nonrenewable or having final growth, like the hooks in Clione (Gastropoda, Gymnosomata). In this case, they are formed by a single cell. Conversely, they can be renewable during the entire life span and in this case they are formed by a set of cells, like the formation of the radula. The fine structure of the jaws was studied in the gastropod Puncturella noachina. The jaw is situated in the buccal cavity and consists of paired elongated cuticular plates. On the anterior edge of each cuticular plate there are numerous longitudinally oriented rodlets disposed over the entire jaw surface and immersed into a cuticular matrix. The jaw can be divided into four zones situated successively toward the anterior edge: 1) the posterior area: the zone of formation of the thick cuticle covering the entire jaw and forming the electron-dense outer layer of the jaw plate; 2) the zone of rodlet formation; 3) the zone of rodlet arrangement; and 4) the anterior zone: the free scraping edge of the plate, or the erosion zone. In the general pattern of jaw formation, Puncturella noachina resembles Testudinalia tessulata (Patellogastropoda) studied previously. The basis of the jaw is a cuticular plate formed by the activity of the strongly developed microvillar apparatus of the gnathoepithelium. However, the mechanism of renewal of the jaw anterior part in P. noachina is much more complex as its scraping edge consists not just of a thick cuticular matrix rather than of a system of denticles being the projecting endings of rodlets. PMID:24549973

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

    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.

  13. Comparative Mapping of GABA-Immunoreactive Neurons in the Buccal Ganglia of Nudipleura Molluscs.

    Gunaratne, Charuni A; Katz, Paul S

    2016-04-15

    Phylogenetic comparisons of neurotransmitter distribution are important for understanding the ground plan organization of nervous systems. This study describes the γ-aminobutyric acid (GABA)-immunoreactive (GABA-ir) neurons in the buccal ganglia of six sea slug species (Mollusca, Gastropoda, Euthyneura, Nudipleura). In the nudibranch species, Hermissenda crassicornis, Tritonia diomedea, Tochuina tetraquetra, and Dendronotus iris, the number of GABA-ir neurons was highly consistent. Another nudibranch, Melibe leonina, however, contained approximately half the number of GABA-ir neurons. This may relate to its loss of a radula and its unique feeding behavior. The GABA immunoreactivity in a sister group to the nudibranchs, Pleurobranchaea californica, differed drastically from that of the nudibranchs. Not only did it have significantly more GABA-ir neurons but it also had a unique GABA distribution pattern. Furthermore, unlike the nudibranchs, the Pleurobranchaea GABA distribution was also different from that of other, more distantly related, euopisthobranch and panpulmonate snails and slugs. This suggests that the Pleurobranchaea GABA distribution may be a derived feature, unique to this lineage. The majority of GABA-ir axons and neuropil in the Nudipleura were restricted to the buccal ganglia, commissures, and connectives. However, in Tritonia and Pleurobranchaea, we detected a few GABA-ir fibers in buccal nerves that innervate feeding muscles. Although the specific functions of the GABA-ir neurons in the species in this study are not known, the innervation pattern suggests these neurons may play an integrative or regulatory role in bilaterally coordinated behaviors in the Nudipleura. PMID:26355705

  14. Haematopoiesis in molluscs: A review of haemocyte development and function in gastropods, cephalopods and bivalves.

    Pila, E A; Sullivan, J T; Wu, X Z; Fang, J; Rudko, S P; Gordy, M A; Hanington, P C

    2016-05-01

    Haematopoiesis is a process that is responsible for generating sufficient numbers of blood cells in the circulation and in tissues. It is central to maintenance of homeostasis within an animal, and is critical for defense against infection. While haematopoiesis is common to all animals possessing a circulatory system, the specific mechanisms and ultimate products of haematopoietic events vary greatly. Our understanding of this process in non-vertebrate organisms is primarily derived from those species that serve as developmental and immunological models, with sparse investigations having been carried out in other organisms spanning the metazoa. As research into the regulation of immune and blood cell development advances, we have begun to gain insight into haematopoietic events in a wider array of animals, including the molluscs. What began in the early 1900's as observational studies on the morphological characteristics of circulating immune cells has now advanced to mechanistic investigations of the cytokines, growth factors, receptors, signalling pathways, and patterns of gene expression that regulate molluscan haemocyte development. Emerging is a picture of an incredible diversity of developmental processes and outcomes that parallels the biological diversity observed within the different classes of the phylum Mollusca. However, our understanding of haematopoiesis in molluscs stems primarily from the three most-studied classes, the Gastropoda, Cephalopoda and Bivalvia. While these represent perhaps the molluscs of greatest economic and medical importance, the fact that our information is limited to only 3 of the 9 extant classes in the phylum highlights the need for further investigation in this area. In this review, we summarize the existing literature that defines haematopoiesis and its products in gastropods, cephalopods and bivalves. PMID:26592965

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

    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

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

    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

  17. 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

    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.

  18. 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

    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

  19. 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

    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.

  20. Distribuição de Biomphalaria (Gastropoda, Planorbidae nos Estados do Rio Grande do Sul e Santa Catarina, Brasil The distribution of Biomphalaria (Gastropoda, Planorbidae in Rio Grande do Sul and Santa Catarina States, Brazil

    Horacio Manuel Santana Teles

    1991-10-01

    Full Text Available É apresentada análise dos conhecimentos sobre a biogeografia das espécies de Biomphalaria transmissoras de Schistosoma mansoni, abrangendo os Estados do Rio Grande do Sul e Santa Catarina (Brasil bem como o relato do encontro de novas localidades colonizadas pelos planorbídeos. Comenta possibilidade da expansão da esquistossomose ao sul do Brasil.An analysis to determine new localities colonized by the intermediate snail hosts (B. straminea, B. tenagophila and B. tenagophila tenagophila of Schistosoma mansoni from Rio Grande do Sul and Santa Catarina States (Brazil was carried out. As regards the geographical distribuition of the schistosomiasis vector, the possible extension of the endemic disease to Southernmost Brazil is commented on.