Deep sea samples obtained during the 1987 cruise of the RV Marion Dufresne along the southeastern Brazilian coast provided material of two species of Valettiopsis Holmes, 1908 (Crustacea, Amphipoda). Valettiopsis macrodactyla Chevreux,1909 is redescribed and has its distribution extended to the south-western Atlantic. Valettiopsis ruffoi n.sp.is described and can be distinguished from other Valettiopsis species by the slender gnathopods 1 and 2, coxa 4 deeply excavate posteriorly, and outer ramus of uropod 3 with distal article about 1/13 of proximal article. Notes on the geographical distribution of the genus and a key for the Valettiopsis species are provided.
Crustacea, Amphipoda, Lysianassoidea, Valettiopsis, Brazil, southwestern Atlantic, new species.