A new genus and new species of Vesicomyidae (Mollusca, Bivalvia) from cold seeps on the Barbados accretionary prism, with comments on other species

A new genus of Vesicomyidae, Laubiericoncha n. gen. is described. It includes four species: L. myriamae n. sp. (type species) from the Barbados accretionary prism, L. chuni (Thiele & Jaeckel, 1931) n. comb. from cold seeps in the Gulf of Guinea (Cameroon to seep sites near the Congo Canyon), L. angulata (Dall, 1896) n. comb. from the Gulf of Panama and L. suavis (Dall, 1913) n. comb. from Baja California. Two other undescribed species are tentatively placed in the genus pending the availability of fresh material for further research. Laubiericoncha myriamae n. sp. and L. chuni n. comb. are described in detail. Species in the new genus are characterized by an oblong shell with the posteriormost point at or just above the horizontal midline and the postero-dorsal area with two shallow and rounded ridges, absence of lunule and escutcheon, a well-marked triangular pallial sinus, a diverging hinge dentition with rather long and thin but prominent cardinal teeth and gills with two demibranchs on each side.