Padrões distributivos e zoogeografia dos moluscos da plataforma continental brasileira: Parte III. Comissão Oceanográfica Espiríto Santo I Distribution patterns and zoogeography of the mollusks from the Brazilian continental shelf: Part III. Oceanographic Expedition Espirito Santo I

Ricardo Silva Absalão

Padrões distributivos e zoogeografia dos moluscos da plataforma continental brasileira: Parte III. Comissão Oceanográfica Espiríto Santo I Distribution patterns and zoogeography of the mollusks from the Brazilian continental shelf: Part III. Oceanographic Expedition Espirito Santo I

1989

Ricardo Silva Absalão

<abstract language="eng">One hundred senventy-five species of marine mollusks have been identified in the Expedition Espírito Santo I. Standing out the species Margarites olivaceus (Brown, 1827); Cyclostremiscus caraboboensis Weishord, 1962; Balcis gibba Folin, 1867; Triphora compsa (Dall, 1927); Henrya af. goldmani Bartsh, 1947 and Limaea subovata Jeffreys, 1876 as they have not been previously assigned to Brazil. The analysis of the geographical distribution patterns points out the dominance of the species with thermophiles affinities. This situation evidences the importance of the Brazilian Current in the maintanance of the biogeographical structure of the studied region. However, it is the analysis of the cryophiles species that shows the Cabo Frio region as an ecological filter quite more permeable to the species with thermophile affinities than to the cryophiles ones. The existence of this barrier and the endemism rate (4.27%) characterize the region that extends from the south of Cabo Frio as a transition between the two patterns cited above. Therefore they do not corroborate in malacological parameters the proposition made by Palacio (1982) for the individualization of the Paulista Province.

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