Biodiversity of Marine Nematodes in the South American Coast

V. VENEKEY; C. T. PASTOR DE WARD; V. LO RUSSO; V. FONSECA-GENEVOIS; P. SANTOS

Ghent

Congreso; 14th International Meiofauna Conference; 2010

Research Group Marine Biology. Biology Department. Ghent University

This study analyses the biodiversity of marine nematodes in the South American coast taking into account country (Brazil and Argentina), habitat (rocky shore, estuary and sandy beach) and latitudinal variations (0-15°N, 0-15°S, 15-30°S, 30- 45°S, 45-60°S). The genus and species records of nematodes from the Brazilian and Argentinean coast available until December 2009 in PhD theses, MSc dissertations, undergraduate papers and other manuscripts were used to construct a uniform data set with presence/absence data as the basis for comparisons. As a first result, it was found that by the end of 2009 a total of 308 genera of nematodes had been recorded for marine environments on the South American coast. The nematofauna composition in the environments is similar to other places sampled worldwide, with the families Chromadoridae and Xyalidae as the most representative. Comparing the habitats, it was determined that only estuary and sandy beaches were significantly different in composition at genus level (ANOSIM, Global R=0.497, p=0.0001). Furthermore, no significant differences were found to latitudes (ANOSIM, Global R=0.195, p=0.001) and neither to the genera composition of Brazil compared to Argentina (ANOSIM, Global R=0.270, p=0.001). The Chi-square test did not detect differences between the frequency of habitats studied between Brazil and Argentina (x2=3.95, p>0.05). The results above point out that the latitudinal factor does not affect the genera composition. In the South American coast, only habitat influences the Nematoda generic composition.