Ultrastructural study of spermiogenesis and the spermatozoon of Cavisoma magnum (Southwell, 1927) (Acanthocephala, Palaeacanthocephala, Cavisomidae), from Siganus lineatus (Pisces, Teleostei, Siganidae) (Valenciennes, 1835) in New Caledonia

• Published in: Micron (Oxford, England : 1993) England : 1993), 2012-02, Vol.43 (2), p.141-149
• Main Authors: Foata, J., Quilichini, Y., Justine, J.-L., Bray, R.A., Marchand, B.
• Format: Article
• Language: English
• Subjects: Acanthocephala; Acanthocephala - cytology; Acanthocephala - isolation & purification; Acanthocephala - physiology; Animals; Biochemistry, Molecular Biology; Cavisoma magnum; Cavisomidae; centrioles; chromatin; fish; Fish Diseases - parasitology; Flagella - ultrastructure; flagellum; granules; Life Sciences; Male; Marine; Microscopy, Electron, Transmission; New Caledonia; Organelles - ultrastructure; Palaeacanthocephala; parasites; Perciformes - parasitology; phylogeny; Pisces; Rotifera; Siganidae; Siganus; Siganus lineatus; Spermatogenesis; spermatozoa; Spermatozoa - ultrastructure; Spermatozoon; Spermiogenesis; Teleostei; TEM; transmission electron microscopy; Ultrastructure; ultrastructure, spermatozoon, spermiogenesis, cavisoma magnum, acanthocephala, TEM
• ISSN: 0968-4328; 1878-4291
• DOI: 10.1016/j.micron.2011.10.022

► Description of ultrastructure of spermiogenesis and spermatozoon of a cavisomatid. ► Elaboration of a flagellum of 9 + 2 pattern during spermiogenesis. ► Specificity of the distribution, size and form of protein granules in the mature spermatozoon. ► Posterior extremity appears like a lamina. This paper presents an ultrastructural study of Cavisoma magnum (Acanthocephala, Cavisomatidae) with a Transmission Electron Microscopy tool. This parasite of the fish Siganus lineatus is here reported for the first time from off New Caledonia, South Pacific. It is the first study describing the ultrastructure, spermiogenesis and spermatozoon of a species of the family Cavisomatidae. The young spermatid of C. magnum possesses a centriole constituted of doublets without a central element. After the elaboration of a flagellum of 9 + 2 pattern, the centriole migrates in a nuclear groove. Then the flagellum migration occurs and gives rise to a spermatozoon. The distribution and the size of the protein granules are reported and the posterior extremity appears like a chromatin lamina wave. Comparative ultrastructural data are presented on sperm and spermiogenesis of the Acanthocephala and Rotifers examined to date and the phylogenetic implications are discussed.