Further report of Bariaka alopiae Cressey, 1966 (Copepoda, Siphonostomatoida) from the Indian Ocean with new host and geographic record.

A copepod parasite, Bariaka alopiae Wilson, 1932 (Eudactylinidae) infested on thresher sharks caught from the Indian Exclusive Economic Zone off Andaman and Nicobar archipelago, eastern Indian Ocean is further reported. Adult females of B. alopiae were collected from the gill filaments of two host species, Alopias pelagicus Nakamura and A. superciliosus Lowe. The species B. alopiae can be easily distinguished from other species within the genus by the following characteristic features: cylindrical body devoid of spines, eighteen segmented antennules and four segmented abdomen. In the Indian Ocean, this parasite was known only from its original description 51 years ago, based on materials from western Indian Ocean off Madagascar. Further the present study reports, A. pelagicus as a new host for this parasite.