Brachyura da plataforma meridional do Rio Grande do Sul, Brasil (Crustacea, Decapoda)

Abstract

Brachyura from 298 stations (Project decapod crustacens from the Rio Grande Coast – Rv “Atlântico Sul” – 1982-84) on the southern Brazilian shelf (31° 30 S – and 49°50 w – 52°30 w), between 8 and 200 m, were analyzed. Otter trawl and picard s dredge were utilized. A brachyuran fauna list (44 species, 39 genus, 12 families is provided and discussed. The number of species in each family was: majidae (9): portunidae (8); xanthidae (6); pinnotheridae (5); goneplacidae (4); leucosiidae and parthenopidae (3); calappidae (2); dromiidae, homilidae, latreillidae and palicidae (1). Lithadia oblique, pyromania tuberculata, heterocrypta granulate, hexapanopeus angustifrons, H, paulensis, panopeus bermudensis and tumidotheres maculatus had treir first record for the Rio Grande do Sul State. Myropsis quinquespinosa. Callinectes danae, callinectes ornatus and allactaea lithostrota are transferred from their forme patterns to new ones according to the distributional patterns. Lithadia o bliqua, nibilia antilocapra, P. tuberculata, speocarcunus meloi and pinnixa brevipollex were classified under these paltherns for the first time. There is a clear indication of the decrease in species from the north to the Rio Grande do Sul Continental Shelf. Melo (1985) suggestion that the southern Brazilian coast is a barrier to the thermophile especies due to the action of waters from Argentina is the majority of the samples, and for having the highest number of individuais.