The genera Catoessa, Elthusa, Enispa, Ichthyoxenus, Idusa, Livoneca and Norileca n.gen. (Isopoda, Cymothoidae), crustacean parasites of marine fishes, with descriptions of eastern Australian species
Abstract
The following genera of Cymothoidae are recorded from Australia: Catoessa Schiodte & Meinert, Elthusa Schiodte & Meinert, Enispa Schiodte & Meinert, Ichthyoxenus Herklots, Livoneca Leach and Norileca n.gen. Full diagnoses are given for Enispa, Livoneca and Norileca n.gen. For the remaining genera provisional diagnoses are given. Idusa Schiodte & Meinert is rediagnosed to allow separation from Catoessa. All the species described herein would have previously been placed in Livoneca. Examination of the type material of L. redmanii shows that all other species placed in the genus, except for L. bowmani Brusca, are not congeners, and are reassigned, where possible, to other genera. The genus Livoneca is found to belong to the Anilocrinae, and is most closely related to the Nerocila group of genera. The principal characters used in redefining these genera and assigning Livoneca and Norileca to the Anilocrinae are the morphology of the brood pouch, pleopods, pleon and cephalon. The species described are Catoessa ambassae n.sp., Elthusa myripristae n.sp., E. neocytta (Avdeev), E. propinqua (Richardson), E. raynaudii (Milne-Edwards), E. sacciger (Richardson), E. sigani n.sp., E. turgidula (Hale), Enispa irreqularis (Bleeker), lchthyoxenus minabensis (Shiino), Norileca indica (Milne-Edwards) and Norileca triangulata (Richardson). Discussion is given of the genera treated and the problems present in attempting to diagnose subfamilies within the Cymothoidae. Keys are given to the Australian gill attaching genera and the Australian species of the genera Elthusa and Norileca.
