title: Ultrastructural characteristics of the mature spermatozoon of the digenean Sclerodistomum italicum (Stossich, 1893) (Hemiuroidea, Sclerodistomidae) intestinal parasite of Hypocanthus amia (Teleostei, Carangidae).
abstract: The mature spermatozoon of Sclerodistomum italicum is filiform, tapered at both ends and shows the following features: 2 axonemes of the 9+"1" pattern of the Trepaxonemata, mitochondrion, nucleus and parallel cortical microtubules. The specific features of the spermatozoon of S. italicum include the simultaneous presence of two types of extramembranous ornamentations, the presence of short cortical microtubules in the anterior part of the spermatozoon and the presence of only one bundle of cortical microtubules in the median part of the spermatozoon. Thus far these structures are known only in the Hemiuroidea. The presence of filamentous ornamentation in the anterior extremity of the spermatozoon has not previously been described in the Sclerodistomidae. Similar to spermatozoa of other hemiuroideans, S. italicum lack spine-like bodies described in spermatozoa of many digenean taxa. The posterior extremity of the spermatozoon exhibits the same ultrastructural characteristics typical of the Hemiuroidea.
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. Electronic address: ibnou.ndiaye@ucad.edu.sn.
authors.forename: Papa Ibnou
authors.initials: PI
authors.lastname: Ndiaye
authors.affiliation: UMR SPE 6134, CNRS - Università di Corsica, SERME Service d'Etude et de Recherche en Microscopie Electronique, Campus Grimaldi, 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: Adji Mama
authors.initials: AM
authors.lastname: Marigo
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: Department of Biology, University of North Dakota, Grand Forks, ND, USA.
authors.forename: Vasyl V
authors.initials: VV
authors.lastname: Tkach
authors.affiliation: UMR SPE 6134, CNRS - Università di Corsica, SERME Service d'Etude et de Recherche en Microscopie Electronique, Campus Grimaldi, 20250 Corte, Corsica, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Marchand
mesh_terms: D000818:Animals; D007422:Intestines / Q000469:parasitology; D008297:Male; D046529:Microscopy, Electron, Transmission; D010473:Perciformes / Q000469:parasitology*; D013094:Spermatozoa / Q000648:ultrastructure*; D014200:Trematoda / Q000472:pathogenicity / Q000648:ultrastructure*; D014201:Trematode Infections / Q000469:parasitology*
keywords: Digenea; Sclerodistomidae; Sclerodistomum italicum; Sperm; Ultrastructure