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Brian L James - One of the best experts on this subject based on the ideXlab platform.
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the metacercariae of sibling species of meiogymnophallus including m rebecqui comb nov digenea gymnophallidae and their effects on closely related Cerastoderma host species mollusca bivalvia
Parasitology Research, 1996Co-Authors: Eric Bowers, Pierre Bartoli, Fernanda Russellpinto, Brian L JamesAbstract:The morphology and ecology are described for four sibling species of digenean metacercariae: Meiogymnophallus minutus (Cobbold 1859), M. strigatus (Lebour 1908) from the estuarine cockle Cerastoderma edule L. and M. fossarum (Bartoli, 1965) and M. rebecqui (Bartoli, 1983) comb. nov. from the brackish water lagoon cockle C. glaucum (Poiret). Although occupying different sites within the two species of cockle, both M. minutus and M. fossarum infections result in pathological effects that may cause heavy host mortality. Remarkably, they also result in an inversion of the cockles in situ in the sand such that predation by the final host species is enhanced.
Karel Essink - One of the best experts on this subject based on the ideXlab platform.
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long term indirect effects of mechanical cockle dredging on intertidal bivalve stocks in the wadden sea
Journal of Applied Ecology, 2002Co-Authors: Theunis Piersma, Anita Koolhaas, Anne Dekinga, J J Beukema, Rob Dekker, Karel EssinkAbstract:Summary 1. There is world-wide concern about the effects of bottom-dredging on benthic communities in soft sediments. In autumn 1988, almost a third of the 50-km 2 intertidal system around the island of Griend in the western Dutch Wadden Sea was suction-dredged for edible cockles Cerastoderma edule and this study assessed subsequent effects. An adjacent area not directly touched by this fishery and an area from which the mussel Mytilus edulis beds were removed, served as reference areas. 2. Sediment characteristics, together with the total stock size and settlement densities of Cerastoderma , Baltic tellin Macoma balthica and soft-shelled clam Mya arenaria , were documented during 11 successive autumns before (August‐September 1988) and after (August‐September 1989‐98) the suction-dredging event in fished and unfished areas. Four other areas in the Dutch Wadden Sea, where changes in densities of juvenile bivalves from 1992 to 1998 were measured, served as additional reference locations.
J M Jansen - One of the best experts on this subject based on the ideXlab platform.
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mesheften ensis directus strandschelpen spisula subtruncata kokkels Cerastoderma edule mosselen mytilus edulis en otterschelpen lutraria lutraria in de nederlandse kustwateren in 2009
IMARES Wageningen Report, 2009Co-Authors: P C Goudswaard, J J Kesteloo, K J Perdon, J G Jol, C Van Zweeden, J M JansenAbstract:Het doel van deze inventarisaties is het in kaart brengen van de bestanden van commercieel interessante soorten en het weergeven van de fluctuaties in de tijd, ten behoeve van het visserijbeleid. Het onderzoek is in eerste instantie gericht op de Amerikaanse zwaardschede (mesheften) (Ensis directus), de halfgeknotte strandschelp (Spisula subtruncata) en de kokkel (Cerastoderma edule). Daarnaast bleek er een voortgezette toename van een voorheen minder algemene soort, de gewone otterschelp (Lutraria lutraria), tot een niveau dat commerciele exploitatie wellicht mogelijk maakt. In dat perspectief is de otterschelp in de berekening van de bestanden meegenomen.
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mesheften ensis directus halfgeknotte strandschelpen spisula subtruncata kokkels Cerastoderma edule en otterschelpen lutraria lutraria in de nederlandse kustwateren in 2008
2008Co-Authors: P C Goudswaard, J J Kesteloo, K J Perdon, J M JansenAbstract:Ten behoeve van het beleid voor de visserij op Amerikaanse zwaardschedes (mesheften) (Ensis directus), halfgeknotte strandschelpen (Spisula subtruncata) en kokkels (Cerastoderma edule) heeft Wageningen IMARES, in opdracht van LNV het bestand in de Nederlandse kustwateren geinventariseerd. Deze inventarisatie is uitgevoerd in het voorjaar van 2008 en is daarmee de veertiende opeenvolgende survey die op deze manier sinds 1995 wordt uitgevoerd.
Sónia Mendo - One of the best experts on this subject based on the ideXlab platform.
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Effects of metal contamination on the gene expression profile of two benthic species: Cerastoderma edule and Ruditapes philippinarum
Marine pollution bulletin, 2017Co-Authors: Raquel Rodrigues, Joana Lourenço, Patrícia Pereira, Susana Carvalho, Sónia MendoAbstract:This study aimed to identify new biomarkers for metal exposure in two bivalve species. Suppressive Subtractive Hybridization (SSH) was employed to evaluate the transcriptomic response of Cerastoderma edule and Ruditapes philippinarum to metal pollution. Protein synthesis and catalytic activity were the most affected metabolic processes in C. edule and R. philippinarum, respectively. Also, different genes responded to the effect of contamination in each species. The different response observed in both species reinforces the importance of including more than one bioindicator species in risk assessment studies. These results provide the basis for new studies, which are necessary for further validation of the use of the identified genes as molecular biomarkers for metal exposure.
Anne Chenuil - One of the best experts on this subject based on the ideXlab platform.
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Survival of male and female Cerastoderma glaucum (Bivalvia) during aerial exposure
Vie et Milieu Life & Environment, 2012Co-Authors: Katarzyna Tarnowska, A. Verney, Maciej Wolowicz, Jean-pierre Féral, Anne ChenuilAbstract:The lagoon cockle, Cerastoderma glaucum (Poiret, 1789) usually inhabits small, often isolated, water basins. Dispersal among these basins can take place overland (human mediated) or by migratory birds, when cockles are attached to their bodies. It requires the capacity of the cockle to survive aerial exposure. The time of survival of cockles in air was tested. The LT50 was of 80 h at 15 °C and 43 h at 22 °C. There was no significant difference in survival time neither among size classes, nor between males and females. The similarity between male and female mortality curves and the strong differences between the results coming from two thermal conditions suggest that the experiment was reliable.
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SURVIVAL OF MALE AND FEMALE Cerastoderma GLAUCUM (BIVALVIA) DURING AERIAL EXPOSURE
2012Co-Authors: Katarzyna Tarnowska, A. Verney, Jean-pierre Féral, Maciej Wołowicz, Anne ChenuilAbstract:The lagoon cockle, Cerastoderma glaucum (Poiret, 1789) usually inhabits small, often isolated, water basins. Dispersal among these basins can take place overland (human mediated) or by migratory birds, when cockles are attached to their bodies. It requires the capac- ity of the cockle to survive aerial exposure. The time of survival of cockles in air was tested. The LT 50 was of 80 h at 15 °C and 43 h at 22 °C. There was no significant difference in survival time neither among size classes, nor between males and females. The similarity between male and female mortality curves and the strong differences between the results coming from two thermal conditions suggest that the experiment was reliable. AeRIAL exPoSuRe Cerastoderma glauCum Sex-BIASeD DISPeRSAL
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Comparative phylogeography of two sister (congeneric) species of cardiid bivalve: Strong influence of habitat, life history and post-glacial history
Estuarine Coastal and Shelf Science, 2012Co-Authors: Katarzyna Tarnowska, Jean-pierre Féral, Maciej Wołowicz, Manuela Krakau, Sabine Jacobsen, Anne ChenuilAbstract:Sister (congeneric) species may exhibit disparate patterns of biogeographic genetic structures due to different life histories and habitat preferences. The common cockle Cerastoderma edule and the lagoon cockle Cerastoderma glaucum probably diverged from their common ancestor in the present territory of Sahara around 5 million years ago. Although it is difficult to separate both species morphologically, various genetic markers, both mitochondrial and nuclear, clearly distinguish them. Furthermore, their lifestyles are different, as C. edule has a much less fragmented coastal habitat and a longer duration of pelagic larval stage than C. glaucum. A comparative genetic analysis was conducted on 17 populations of C. edule and 13 populations of C. glaucum using a 506 bp fragment of mitochondrial DNA (COI).We tested the hypothesis that differences in habitat types and life history are reflected in the genetic structure patterns of these two cockles. Indeed substantial differences in population genetic structures between them are revealed. Genetic diversity within C. glaucum populations decreases northwards as a consequence of post-glacial (re)colonization from southern refugia, while C. edule displays an opposite pattern indicating survival in glacial refuges in the northern Atlantic. Among populations within geographic groups, genetic differentiation is low in C. edule, probably as a result of larval dispersal with coastal currents, while it is extremely high in C. glaucum, best explained by the fragmented habitats. Interestingly, long distance divergence is less expressed in C. glaucum than in C. edule, which supports the speculation that migrating birds (frequently observed in lagoons) may occasionally transport the former more often or more efficiently than the latter. The approach applied in this study (e.g., rarefaction procedure, selection of samples of both species from the same regions) enabled a new and reliable comparative analysis of the existing raw datasets.
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Complex genetic population structure of the bivalve Cerastoderma glaucum in a highly fragmented lagoon habitat
Marine Ecology Progress Series, 2010Co-Authors: Katarzyna Tarnowska, Jean-pierre Féral, Anne Chenuil, Raisa Nikula, Maciej WołowiczAbstract:The genetic structure of a lagoon specialist, the bivalve Cerastoderma glaucum, was studied from 4 nuclear microsatellite loci and sequences from a 514 bp mitochondrial DNA region. Both marker types revealed strong differentiation among populations that is likely due to the highly fragmented distribution of this species. The geographic location and strength of the major divisions were different between the genomes. The deepest phylogeographic split in mtDNA grouped Aegean Sea and Ponto-Caspian region populations against the more western populations, whereas nuclear data singled out Ionian Sea populations or indicated a Ponto-Caspian character of nuclear DNA from the Ionian Sea. In agreement with their presumably rapid post-glacial establishment, the northern populations showed evidence of founder effects and strong genetic drift in their genetic structuring. Two unexpected geographic disjunctions were detected in the mtDNA, but not in the microsatellite characteristics, of the studied populations. We suspect long-distance dispersal via migrating birds to be a probable dispersal means among isolated lagoon habitats and to have generated the disjunctions by contributing to the post-glacial spread of C. glaucum to its northern distribution area. The discrep- ancies between the nuclear and mitochondrial genetic characteristics of the populations could be a result of selective sweeps in mtDNA, sex-biased dispersal, biased effective sex ratio or differential introgression of the genomes. The high level of differentiation found between the main genetic groups led us to conclude that the taxonomy of Cerastoderma needs revision, but we acknowledge that due to hybridization the taxa can be occasionally impossible to delineate.