A new species of parasitic copepod of the genus Hatschekia Poche, 1902 (Siphonostomatoida: Hatschekiidae) from filefishes (Pisces: Tetraodontiformes: Monacanthidae) from off Okinawa, Japan.

Hatschekia khahajya n. sp. is described from the gill filaments of two monacanthid fishes, Cantherhines dumerilii (Hollard) and Amanses scopes (Cuvier), caught off Okinawa, Japan. The new species can be distinguished from its congeners by the possession of the following combination of characters: cephalothorax length/trunk length ratio greater than 0.40; cephalothorax with a pair of lateral bars on the chitinous ring and a posterior pair of surface ridges; trunk with a bifurcate chitinous frame extending over its anterior third and with well-developed posterior lobes that extend beyond the abdomen; and four processes plus two spinular rows on the distal margin of the intercoxal sclerite of legs 1 and 2.