Zoological Studies

Four Species of Unicolax Cressey and Cressey, 1980 (Copepoda: Bomolochidae) Parasitic on Marine Fishes of Taiwan

Ching-Long Lin and Ju-shey Ho (2006) Four species of bomolochid copepods belonging to the genus Unicolax Cressey and Cressey, 1980 were discovered parasitic in the nasal sinuses of marine fishes of Taiwan. They are U. ciliatus Cressey and Cressey, 1980 on Scomberomorus commerson (Lacepéde); U. collateralis Cressey and Cressey, 1980 on Euthynnus affinus Cantor; U. longispinus sp. nov. on Psenopsis anomala (Temminck and Schlegel); and U. quadrispinulus sp. nov. on Sillago sihama (Forsskål). The distinguishing feature of U. longispinus is the transformation of the 4th element on the antennule in the female into a long spine, and that of U. quadrispinulus is the possession of 4 (instead of 3) small outer spines on the terminal segment of the leg 1 exopod in the female. This is the first record of the occurrence of Unicolax on the marine fishes of Taiwan. Unicolax chrysophryenus Roubal, Armitage and Rohde, 1983 is proposed for transfer to Naricolax Ho, Do and Kasahara, 1983 and a key to the 7 species of Unicolax is provided.