This note relates the occurrence of Evadne spinifera Müller, 1867 (Crustacea, Branchiopoda) in Guanabara Bay, Rio de Janeiro State, Brazil. The samples were obtained by vertical tows with a 200µm mesh-size conical net at different times over a four day period in September, 1995. Evadne spinifera densities was always low.
Cladocera; Evadne spinifera; zooplankton; Guanabara Bay; Brazil