New Taxa of Brachyuran Crabs from Deep Water off Western Peru and Costa Rica

Abstract

Five new species and one new genus of brachyuran crabs obtained by E. M. del Solar and E. Fernandez-B. are described and illustrated. Of these, Homolodromia robertsi, Acanthocarpus delsolari, Pilumnus fernandezi, and Trizocarcinus peruvianus are most closely related to western Atlantic deep-water species, whereas. Delsolaria enriquei, a new genus and species, is a west American endemic. The family Homolodiomiidae and the genera Homolodromia and Acanthocarpus are reported for the first time from the eastern Pacific. It is postulated that the analogous pairs of deep-water Amphi-american species have been separated since free communication existed at or near the depths at which they presently occur. The Bolivar Trench which extends across northern South America is suggested as the probable Miocene or earlier connection.