Rostromysis bacescuii gen. et sp. nov. and Megalopsis den-ticauda gen. et sp. nov. (Crustacea -- Mysidacea) from the south-west coast of Australia

Rostromysis bacescuii gen. et sp. nov. and Megalopsis denlicaudagen. et sp. nov. belonging to the tribe Leptomysini are describedfrom the south-west coast of Australia. The characters uniqueto the genus Rostromysis are the unusually long club-shapedrostrum and the large delicate lamella-like pleopods of thefemale, thus easily distinguishing it from the allied generaTenagomysis and Doxomysis. The genus Megalopsis is closely alliedto Leptomysis, Prionomysis and Promysis but is readily distinguishablein having a short linguiform uncleft telson with a pair of medianplumose setae.