Biodiversidade dos Echinodermata da Baía do Araçá, São Sebastião, SP

Abstract

The aim of the present work is to study the biodiversity of Echinodermata from Araçá Bay, São Sebastião (SP). We analyzed the material from Biota Project / FAPESP -"Biodiversity and functioning of a subtropical coastal ecosystem: a contribution to integrated management", Proc. No 2011 / 50317-5. Diversity and density avaliations of these organisms were performed to: (i) build an inventory of Echinodermata; (ii) morphological taxonomic studies with detailed descriptions and specific discussions to Ophiuroidea, including illustrations and photomicrographs of species and expansion of existing descriptions and (iii) study the factors that influence the richness and abundance in microscale. The echinoderms were sampled in the intertidal zone to 23 m deep, rocky shores, and as associated fauna of sponges. The 863 specimens collected were classified into four classes, 13 families, 19 genera and 25 species, corresponding to 8.3 % of echinoderms registered for the Brazilian coast. The Ophiuroidea was the most diverse with 16, with two being are new records for the Araçá Bay: Amphiura kinbergi and Ophiothela danae. For species of brittle stars, there was a further taxonomic study with descriptions of external and internal morphology (arm ossicles), that enriched the existing descriptions.The highest richness and diversity of this group was observed in infralitoral when collected with a dredge. Amphiuridae and Ophiactidae were the most representative brittle stars families and accounted for approximately 80 % of brittle stars sampled. The results of this work will contribute consistently to the knowledge of the echinoderms diversity in São Paulo, will be the basis for future monitoring of the human activities impact on the bay will contribute to this rich conservation actions implementations environment.