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Biota Neotropica 2011
A comparative study of the Bivalvia (Mollusca) from the continental shelves of Antarctica and BrazilDOI: 10.1590/S1676-06032011000100014 Keywords: checklist, shallow waters, brazilian fauna, antarctic fauna. 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). a large number of brazilian species of infaunal (e.g., tellinidae, veneridae, cardiidae, and mactroidea) and epifaunal groups (pectinidae, mytilidae, and arcidae) are absent from or poorly represented in antarctica. nuculanoidea, limopsoidea, lucinoidea, galeommatoidea, cyamioidea, and cuspidarioidea are the richest groups in antarctica; some of them are also represented by several species in brazil, albeit in deeper waters. three species are recorded as living in both places: limatula pygmaea (limidae), lasaea adansoni (lasaeidae), and gaimardia trapesina (gaimardiidae). through the analysis of these groups from each fauna, it is possible to identify those that are taxonom
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