Ultrastructural study of the coccidian Cryptosporidium sp. from stomachs of juvenile cichlid fish

Infection by the coccidian Cryptosporidum sp. was found in the stomach of cultured cichhd fry and fingerlings. Merogony and gamogony stages were located at the rnicrovlllous zone of the superficial cells of the stomach epithelium while oogony and sporogony stages were located intracellularly within the mucosal epithelium. Epithelially attached stages were covered by a mi- crov~llous membrane. These structural and developmental characteristics have not been reported previously in other C q ~t o s p o r i d ~u m species.