A survey on coccidian infection of Lake Biwa fishes in Japan, with the description of four new species of Goussia Labbe, 1896 (Apicomplexa)

Thirty-two specimens of 11 freshwater fish species from Lake Biwa, Japan we re surveyed for coccidian infections. Four fish species proved to be infect ed with apicomplexans belonging to the genus Goussia. Altogether, seven Gou ssia species were found. Oocysts of four species inhabiting the intestinal epithelium were shed at the sporulated stage. Two other intestinal species left the fish unsporulated. A few relatively large and aged oocysts of a fu rther species were found in the renal tubules. The sporulated intestinal sp ecies were described as Goussia biwaensis n. sp., G. grygieri n. sp., G. ni pponica n. sp. and G. wakabayashii n. sp.