Partição ambiental de Potimirim glabra (Kingsley) e Potimirim potimirim (Müller) (Crustacea, Decapoda, Atyidae) no rio Sahy, Mangaratiba, Rio de Janeiro, Brasil

This work aims to determinate the spatial distribution of two sympatric freshwater shrimp species, Potimirim glabra (Kingsley, 1878) and Potimirim potimirim (Müller, 1881) in Sahy River, municipality of Mangaratiba. The populations were collected from September, 1997 to February, 1999. The animals were collected monthly by sieving the marginal vegetation, on rocky surface and among litter on river bottom. The animals were sorted sexed. Their carapace length measured and total length measured. A total of 4,889 animals were collected in Sahy River: 3,281 P. glabra and 1,608 P. potimirim. The sp...