A new species of the genus Halicyclops (Copepoda, Cyclopoida, Cyclopidae) from freshwater in Central Vietnam

Abstract

ABSTRACT:A new cyclopoid species, Halicyclops songsonensis Tran, Le & Ho, sp. n., from the Son River, Quang Binh Province, Central Vietnam is described. The new species is distinguished from its other congeners by having the spine formula of 3:4:4:3 on P1-P4, lateral angular protuberances on the genital double-somite, a serrate hyaline frill of pre-anal somite slightly larger on dorsal part than that on lateral and ventral parts, relatively long caudal rami, spiniform seta of proximalmost seta on P2-P3 Enp3 and showing the round/oval integumental windows on cephalothorax and two next prosomites.