title: Topography and ultrastructure of the tegument of Bucephalus anguillae (Digenea: Bucephalidae), a parasite of the European eel Anguilla anguilla (Osteichthyen: Anguillidae).
abstract: The tegumental ultrastructure of the intestinal fluke Bucephalus anguillae was studied with the use of scanning and transmission electron microscopy. The surface of the tegument is covered by transverse ridges from which protrude numerous closely packed, digitated, and claw-shaped spines. Cobblestone-like units of the tegument were observed on the crescent-shaped formation of the rhynchus and at the posterior part of the body. Three types of sensory structures were examined, i.e., 2 uniciliated receptors and 1 without cilia. As anterior-posterior differences were observed, particular attention was given to spines and sensory receptors. Spine insertion zones and average cilia length are variable between anterior and posterior tegument areas. Ultrastructural study revealed that the tegument of B. anguillae has a typical syncytial organization with a distal cytoplasm lying over a basal matrix and cytons below. Cytoplasmic bridges allowed transit of secretory vesicles and granules. Diagrams of spines and sensory receptors were made to help in understanding the nature of these structures.
authors.affiliation: CNRS UMR 6134 SPE, University of Corsica Pascal Paoli, Parasites and Mediterranean Ecosystems Laboratory, B.P. 52, 20250 Corte, France. jfilippi@univ-corse.fr
authors.forename: Jean-José
authors.initials: JJ
authors.lastname: Filippi
authors.forename: Yann
authors.initials: Y
authors.lastname: Quilichini
authors.forename: Joséphine
authors.initials: J
authors.lastname: Foata
authors.forename: Bernard
authors.initials: B
authors.lastname: Marchand
mesh_terms: D000811:Anguilla / Q000469:parasitology*; D000818:Animals; D005393:Fish Diseases / Q000469:parasitology*; D005602:France; D005618:Fresh Water; D007411:Intestinal Diseases, Parasitic / Q000469:parasitology / Q000662:veterinary*; D008855:Microscopy, Electron, Scanning / Q000662:veterinary; D046529:Microscopy, Electron, Transmission / Q000662:veterinary; D011984:Sensory Receptor Cells / Q000648:ultrastructure; D014200:Trematoda / Q000145:classification / Q000648:ultrastructure*; D014201:Trematode Infections / Q000469:parasitology / Q000662:veterinary*