Three New Records for Micronesia of Cymothoid Isopods (Crustacea) Parasitic on Fishes

Abstract

Ceratothoa angulata (Richardson) was found in the mouth of Dussumier's halfbeak, Hyporhamphus dussumieri; Cymothoa bychowskyi Avdeev in the gill chamber of the red cornetfish, Fistularia petimba; and Elthusa raynaudii (Milne-Edwards) in the mouth of the blueline snapper, Lutjanus kasmira, collected in Guam. Elthusa raynaudii has only been reported in the Southern Hemisphere, except for one other record in Japan; C. bychowskyi has previously only been found in the Indian Ocean; and C. angulata has previously only been found in the Philippines and Borneo. The blueline snapper is a new host for E. raynaudii. These great range extensions suggest how poorly cymothoid isopods are known.