Elthusa winstoni sp. n. (Iopoda, cymothoidae), a new fish parasitic isopod from Hawaii

Abstract

The new cymothoid species, Elthusa winstoni sp. n., a branchial parasite of fishes from the family Acan-thuridae Bonaparte, 1835 in Hawaii, is described and figured. The female adults can be distinguished by the strongly vaulted body and compacted body shape; rostrum with a small median point; short antennae which are close together (only 6 articles in both antennula and antenna); short and wide uropods extending to half the length of the pleotelson; short dactyli on pereopod 7; and large recurved robust setae on the maxilla. This is the first record of an Elthusa Schioedte & Meinert, 1884 species from the Hawaiian Islands and only the fifth cymothoid described from this region.