Местоположение издательства:UL. RADIO 7, VLADIVOSTOK, RUSSIA, 690041
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Аннотация:The Vesicomyinae Dall et Simpson, 1891, one of the two subfamilies of the family Vesicomyidae, comprises deep-water tiny bivalves distributed from mid-slope to hadal depths in all large oceanic basins. Up to now vesicomyins are a little-known group with uncertain taxonomy, being often considered as a synonym of the family Kelliellidae P.Fischer, 1887.
Presently Vesicomyinae comprises one genus Vesicomya Dall, 1886 with about 14 described species. Vesicomyins are mostly millimetric in size with maximum shell length to 14 mm. In contrast to their larger-sized relatives, pliocardiins, which are living in symbiosis with sulphur-oxidizing bacteria, chemosymbiotrophy has not been proved for vesicomyins so far. At the same time vesicomyins are an important constituent of deep-water trench communities where they were recovered in very large abundances of thousands specimens in one trawl catch.
At present three species have been recorded from the Northwestern Pacific: V. pacifica (Smith, 1885), V. profundi Filatova, 1971 and V. sergeevi Filatova, 1971. The former species is known from the Mid North Pacific at depth of 5220 m, and the two latter occur in the Kuril-Kamchatka Trench at depths of 8125-9530 m.
During recent German-Russian deep-sea expedition KuramBio on board of the R/V Sonne, cruise N 223, to the Kuril-Kamchatka Trench and adjacent abyssal plain new material on vesicomyins was collected from the depths of about 5170-5800 m. Morphological analysis showed that the collection includes two new species. One species is close to the type of the genus, V. atlantica (Smith, 1885), and as well to the representatives of the genus, recorded earlier from the North Pacific. There are such features in common as narrow hinge margins with thin plate-like teeth and the presence of two pairs of demibranchs. The second new species differs from Vesicomya s.s. by broader hinge margin with more radiating teeth and the presence of only one, inner, pair of demibranchs. In contrast to the chemosymbiothic pliocardiins that often have only one pair of demibranchs, gill filaments in the new vesicomyin are not thickened and presumably do not contain symbiothrophic bacteria. Results of molecular analysis of Vesicomya s.s. new species based on COI sequences, suggests close relationships of vesicomyins and pliocardiins. Newly received morphological and molecular data are important for understanding of plesiomorphic character states and trends of morpho-functional adaptations within the vesicomyids in general.