Biota Neotrop., vol. 11, no. 1 A comparative study of the Bivalvia (Mollusca) from the continental shelves of Antarctica and Brazil Flávio Dias Passos1,2 & Frederico Thomaisino Magalhães1 1Department of Animal Biology, Institute of Biology, University of Campinas – UNICAMP, P.O. Box 6109, CEP 13083-970, Campinas, SP, Brazil 2Corresponding author: Flávio Dias Passos, e-mail:
[email protected] PASSOS, F.D. & MAGALHÃES, F.T. A comparative study of the Bivalvia (Mollusca) from the continental shelves of Antarctica and Brazil. Biota Neotrop. 11(1): http://www.biotaneotropica.org.br/v11n1/en/ abstract?article+bn02211012011. Abstract: During identification of bivalve molluscs collected in Antarctica, a rich taxonomic bibliography was gathered, stimulating comparisons with the Brazilian malacofauna. We listed a total of 68 and 368 known shallow-water species (less than 200 m depth) from Antarctica and Brazil, respectively, in order to find species, families and superfamilies in common, and to investigate how these malacofaunas differ in regard to these representative groups and their life habits. There are 23 superfamilies absent in Antarctica, but present in Brazil with at least one species; the reverse does not occur, as all superfamilies known from Antarctica are also recorded from Brazil. The number of Brazilian species is higher, being composed of a mixture of taxa from different biogeographical provinces, whereas in Antarctica there are only a few species adapted to its polar conditions, with minor components from elsewhere. Thus, many typical Caribbean species extend into Brazil, belonging to the diverse Arcoidea, Pectinoidea, Lucinoidea, Cardioidea, Veneroidea, and Tellinoidea. Cemented Ostreoidea, Plicatuloidea, Dimyoidea, Spondylidae (Pectinoidea), and Chamoidea are absent from Antarctica, as are wood (Teredinidae, Pholadoidea) and rock borers (Pholadidae, Pholadoidea; Gastrochaenoidea; and Lithophaginae, Mytiloidea).