title: Ultrastructural characters of the spermatozoa in Digeneans of the genus Lecithochirium Lühe, 1901 (Digenea, Hemiuridae), parasites of fishes: comparative study of L. microstomum and L. musculus.
abstract: This study provides the first ultrastructural data of spermatozoa in the genus Lecithochirium. The spermatozoa of L. microstomum (from Trichiurus lepturus in Senegal) and L. musculus (from Anguilla anguilla in Corsica) exhibit the general pattern described in the great majority of the Digenea, namely two axonemes with the 9 + "1" pattern typical of the Trepaxonemata, one mitochondrion, a nucleus, parallel cortical microtubules and external ornamentation of the plasma membrane. Spermatozoa of L. microstomum and L. musculus have some specific features such as the presence of a reduced number of cortical microtubules arranged on only one side of the spermatozoon, the lack of spine-like bodies and expansion of the plasma membrane. The external ornamentation of the plasma membrane entirely covers the anterior extremity of the spermatozoa. The ultrastructure of the posterior extremity of the spermatozoa corresponds to the pattern previously described in the Hemiuridae, characterized by only singlets of the second axoneme. A particularity of these spermatozoa is the organization of the microtubule doublets of the second axoneme around the nucleus in the posterior part of the spermatozoon.
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: Papa Ibnou
authors.initials: PI
authors.lastname: Ndiaye
authors.affiliation: CNRS - University of Corsica, UMR 6134, "Service d'Étude et de Recherche en Microscopie Électronique", 20250 Corte, Corsica, France.
authors.forename: Yann
authors.initials: Y
authors.lastname: Quilichini
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: Aminata
authors.initials: A
authors.lastname: Sène
authors.affiliation: Department of Biology, University of North Dakota, 10 Cornell street, Grand Forks, ND 58202, USA.
authors.forename: Vasyl V
authors.initials: VV
authors.lastname: Tkach
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: Cheikh Tidiane
authors.initials: CT
authors.lastname: Bâ
authors.affiliation: CNRS - University of Corsica, UMR 6134, "Service d'Étude et de Recherche en Microscopie Électronique", 20250 Corte, Corsica, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Marchand
mesh_terms: D000818:Animals; D054468:Axoneme / Q000648:ultrastructure; D005393:Fish Diseases / Q000469:parasitology; D008297:Male; D013045:Species Specificity; D013094:Spermatozoa / Q000648:ultrastructure*; D014200:Trematoda / Q000166:cytology*; D014201:Trematode Infections / Q000469:parasitology / Q000662:veterinary