Ultrastructure of the spermatozoon of Calliobothrium verticillatum (Cestoda,Tetraphyllidea, Oncobothriidae)
The ultrastructure of the spermatozoon of Calliobothrium verticillatum(Cestoda, Tetraphyllidea, Oncobothriidae) parasite of the smoothhound shark, Mustelus mustelus L.(Pisces, Carcharhiniformes), was studied by transmission electron microscopy. This spermatozoonpresents five regions characterized by several ultrastructural elements: an apical cone, a crestedbody, two axonemes of 9 + “1″ pattern, electron-dense granules, a nucleus and cortical microtubules.In the present study, three of these features were the subject of a detailed attention. The firstis the presence of two axonemes, which confirms that the Tetraphyllidea, Oncobothriidae possess twoaxonemes whereas the Tetraphyllidea, Phyllobothriidae possess only one axoneme. The second is thepresence of one crested body, a criterion homogeneous in the Tetraphyllidea but heterogeneous amongthe different orders of Cestoda. The third is the number and the disposition of corticalmicrotubules. These three criteria seem to be interesting for phylogeny.
Quilichini, Y　Foata, J　Ba, CT　Marchand, B
Univ Corsica, Fac Sci and Tech, Lab Parasites and Mediterranean Ecosyst, F-20250Corte, France
Cestoda　 Tetraphy llidea　 Oncobothriidae　 Calliobothrium verticillatum　spermatozoon　 ultrastructure　 fish　 Mustelus mustelus　 INTESTINAL PARASITE　 SPERMATOLOGICALCHARACTERS　 ELECTRON-MICROSCOPY　 MATURE SPERMATOZOON　 FINE-STRUCTURE　 SPERMIOGENESIS　CYCLOPHYLLIDEA　 PLATYHELMINTHES PHYLOGENY PROTEOCEPHALIDEA
