A New Deep-Sea Enhydrosoma (Copepoda, Harpacticoida, Cletodidae) from the Northern Gulf of Mexico

Abstract

Enhydrosoma texana sp. nov. is described from the northern Gulf of Mexico. The new species is closely related to E. parapropinquum Gómez, 2003 from northwestern Mexico. Both species share several characters including an elongated cylindrical caudal ramus, an abexopodal seta of antennae, the structure of mouthpart appendages, seta formula of thoracic legs P1–P4, the shape of the P5 exopod in the female and the apophysis structure of P3 in males. However, the new species is distinguishable from E. parapropinquum by the shape of the rostrum, number of the antennular segments, the shape of the mandibular palp, the relative lengths of the thoracic legs, the shape of the apophysis of P3 in the male, setal number and length of the P5 exopod of the female, the length of the seta on P5 in the male and the relative lengths of the caudal ramus in both sexes. This is the deepest record of a species in the genus Enhydrosoma.