The results of qualitative and quantitative analyses applied to the assemblages of ostracods recovered from bottom sediments are presented. The samples come from Puerto Rosales, Bahía Blanca estuary, Argentina. Seasonal sampling was performed along a transect perpendicular to the intertidal, from the lower to the upper intertidal. In the lower and upper intertidal the species Loxocythere variasculpta and Callistocythere nucleoperiscum are most abundant; the species Neocytherideis ruidis, Minicythere argentinensis, Cyprideis salebrosa hartmanni and Cyprideis multidentata are also present. In the upper intertidal was recovered only C. s. hartmanni. The qualitative and quantitative variations of the ostracod assemblages can be related to topography, sedimentology, vegetation and salinity variations. The results of this study are of importance in the interpretation of the environments recorded during the Quaternary, since these species are also registered as fossils.

Fil: Kihn, Romina Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina

Fil: Gomez, Eduardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina

Fil: Martínez, Dina Elsa. Universidad Nacional del Sur; Argentina