Marine bivalves from the Argentine coast and shelf: A reassessment of species diversity and faunistic affinities

DIEGO G. ZELAYA

México DF

Congreso; Mollusca 2014: el Encuentro de las Americas. XIII RENAMAC, IX CAMA, LXXX AMS y XLVII WSM; 2014

Sociedad Malacológica de Mexico, American Malacological Society, Latinoamerican Society of Malacology, y Western Society of Malacologists

The Argentine coast, with more than 6.800 Km length, is associated with an extensive continental shelf, that covers a total surface of ca. 1.000.000 Km2 and is up to 850 Km wide at 50°S. Despite the large extension of this area of the southwestern Atlantic Ocean, current knowledge on its bivalve diversity remains scarcely studied and scattered in several publications, most of them issued before 1950. The aim of this contribution is to provide a synthesis of the present knowledge of the living species of marine bivalves occurring in the Argentine coast and shelf.  The information for this study comes from a compilation of all available published literature, considering the species described and reported for the area. The studied area was divided into a 1°square grid to determine the geographic distribution of the species; this analysis also allowed to determine the most and the least studied areas. The present study accounts for a total of 170 valid species, with 88 others currently regarded as synonyms or wrong identifications. Out of the 170 valid species, 67 species appear represented by only one or two records. The most studied area is the coast of Buenos Aires Province, and nearly one third of the total Argentine shelf surface completely lacks information about bivalves diversity. The significance of these results is discussed in the context of the new information obtained in the last years for some particular groups.