Cymbasoma californiense, a new monstrilloid (Crustacea : Copepoda : Monstrilloida) from Baja California, Mexico

Cymbasoma californiense is described from three adult females collected dur ing three cruises carried out in an area adjacent to Bahia Magdalena, a lar ge coastal system on the southwest coast of the Baja California Peninsula, and in the southern Gulf of California. The new species is very closely rel ated to at least three other Cymbasoma (C. longispinosum (Bourne) and its a llies), but can be distinguished by a combination of features including: th e presence of cuticular striations on the forehead, cephalothorax, and geni tal somite; relatively long antennules; the structure of the fifth legs, an d the relative length of the ovigerous spines. Cymbasoma californiense is t he first species of this genus recorded in the Californian region and the E astern Tropical Pacific.