THE SPERMIOGENESIS AND FINE-STRUCTURE OF THE SPERMATOZOON OF NEMATOTAENIA-CHANTALAE DOLLFUS, 1957 (CESTODA, CYCLOPHYLLIDEA, NEMATOTAENIIDAE)

Spermiogenesis of N. chantalae, similar to that of the other Cestodes, is distinguished by: - the orthogonal position of the two basal bodies without intercentriolar body and attached rootlets; - the induction of one flagellum growing parallely to the cytoplasmic expansion with which it unites; - the presence of a looking like flagellar bud in the cytoplasm of the zone of differentiation which, carried away in the sperm body during the nucleus migration, disappears at the end of spermiogenesis; - the cortical microtubule number which increases progressively and their helicoidal coiling; - the nucleus growing thinner looking like a surrounding blade; - the formation of one helicoidal << crested body >> pointed out for the first time in the Cyclophyllidea. The mature spermatozoon, with cytoplasm containing glycogen, has only one axoneme and numerous cortical microtubules following an helical gyration down the sperm body length. It consists of a nuclear region, a cytoplasmic one and a region indicated by the helicoidal << crested body >>.