Hydroid assemblages from SW Atlantic (34º - 43º S)

GENZANO, G.N.; GIBERTO, D.A.; SCHEJTER, L.; BREMEC, C.S.; MERETTA, P.

MARINE ECOLOGY-PUBBLICAZIONI DELLA STAZIONE ZOOLOGICA DI NAPOLI I

Oxford : Blackwell

Año: 2009 vol. 30 p. 33 - 46

0173-9565

This paper updates update taxonomical knowledge and provides ecological information including geographical and bathymetrical distributions and biological substrata for the various hydroid assemblages from the Subantarctic Biogeographical Region, mainly Buenos Aires and the Uruguayan coasts.  Five of the 41 species found are new records for the study region. Thirty-one species (75.6%) , all found at depths shallower than 80m, have cosmopolitan distributions , Biodiversity decreased markedly below  80-m depth, where nine species (≈ 22 %) distributed in the southern hemisphere and one endemic species (2.4%) were found. Most species were non-specific epizoites, occurring on diverse substrata. A non-parametric multivariate similarity analysis revealed nine species groups that were correlated with large-scale and local oceanographic patterns and with the availability of suitable substrata. The main hydroid substrata for eight of the groups were cnidarians, molluscs (mainly blue mussels), quartzite rocks and sponges. In a single group found in patagonian scallop beds, the main biological substrata were polychaete tubes, hydroids and, scallops.