title: Ultrastructure of the spermatozoon of Bothriocotyle sp. (Cestoda: Bothriocephalidea), a parasite of Schedophilus velaini (Sauvage, 1879) (Perciformes: Centrolophidae) in Senegal.
abstract: The mature spermatozoon of Bothriocotyle sp. is filiform and tapered at both extremities. It possesses 2 axonemes of unequal length, showing the 9 + "1" pattern of Trepaxonemata. The anterior extremity exhibits a crest-like body. Thereafter, the crest-like body disappears, and the first axoneme is surrounded by a ring of cortical microtubules (about 27 units) that persist until the appearance of the second axoneme. This ring of cortical microtubules is characteristic only for species of Bothriocephalidea and represents a very useful phylogenetic character. The spermatozoon cytoplasm is slightly electron-dense and contains numerous electron-dense granules of glycogen in several regions. The anterior and posterior extremities of the spermatozoon lack cortical microtubules. The posterior extremity of the spermatozoon of Bothriocotyle sp. possesses a nucleus and a disorganized axoneme, which also characterizes spermatozoa of the Echinophallidae studied to date.
authors.affiliation: Laboratory of Evolutionary Biology, Ecology and Management of Ecosystems, Faculty of Sciences and Techniques, Cheikh Anta Diop University of Dakar, BP 5055, Dakar, Senegal.
authors.forename: Aïssatou
authors.initials: A
authors.lastname: Bâ
authors.forename: Yann
authors.initials: Y
authors.lastname: Quilichini
authors.forename: Papa Ibnou
authors.initials: PI
authors.lastname: Ndiaye
authors.forename: Cheikh Tidiane
authors.initials: CT
authors.lastname: Bâ
authors.forename: Bernard
authors.initials: B
authors.lastname: Marchand
mesh_terms: D000818:Animals; D002589:Cestoda / Q000648:ultrastructure*; D002590:Cestode Infections / Q000469:parasitology / Q000662:veterinary*; D005393:Fish Diseases / Q000469:parasitology*; D008297:Male; D046529:Microscopy, Electron, Transmission / Q000662:veterinary; D010473:Perciformes / Q000469:parasitology*; D012675:Senegal; D013094:Spermatozoa / Q000648:ultrastructure