MONOCHERES CAGARRENSIS SP. NOV. (COPEPODA, SIPHONOSTOMATOIDA) FROM BRAZIL

Monocheres cagarrensis sp. nov., a second species of the genus Monoche res, has been discovered in Rio de Janeiro, Brazil, associated with sp onges. It shows the reduction of the fifth leg to a seta, which charac terizes the genus. M. cagarrensis differs from its congener by the len gth of the siphon which reaches the insertion of P2, and by the presen ce of a group of denticles on the postero-lateral corners of the genit al double-somite, a denticle on the postero-lateral corners of the pos tgenital somite, and 2 setae on the second endopodal segment of the an tenna.