title: Ultrastructural data on the sporogenesis of Myxidium giardi, cépède 1906 (Myxozoa, Myxosporidia), parasite of Anguilla anguilla (Teleostea).
abstract: Ultrastructural study of Myxidium giardi showed that pluricellularity is maintained by the formation of septate desmosomes. The polar capsule is formed from helicoidal depositions of banded material in the initial vacuole. This process makes possible not only the formation of the rigid capsular body but also of the flexible polar filament which is evaginable and reversed in the capsule. The special feature of the genus Myxidium is the ornamentation of the valvogenic cells of the spores in the form of longitudinal ribs. An ultrastructural study showed that the morphogenesis of this cell relief in Myxidium giardi involves a special process based on the development of fusiform macrovesicles whose bases are connected to a cytoskeleton formed of special microtubules 14 nm in diameter. The latter seem to determine the future rigidity of the valvar epicyte.
authors.affiliation: Laboratoire de Parasitologie et Immunologie, Case 096, Université Montpellier II, Montpellier, France.
authors.forename: M H
authors.initials: MH
authors.lastname: Benajiba
authors.forename: A
authors.initials: A
authors.lastname: Marques
authors.forename: G
authors.initials: G
authors.lastname: Bouix