title: [The family Tetraonchidae (Monogenea): its structure and position among the monogeneans].
abstract: The muscle fascicles of the haptor in Tetraonchus monenteron have been described. The muscle connection of the fan-shaped dorsal bars with dorsal anchors is shown. When these muscle fascicles are contracted the dorsal anchors works as pincers. The division of tetraonchids into two genera based on types of copulatory organs, morphology of bars and haptor ans associations with different groups of fishes is restored. Different authors based on ciliated cells and chaetotaxy of the oncomiracidium and comparative spermiogenetic of T. monenteron include the tetraonchids with 16 marginal hooks into the order Dactylogyroidea. In the same time, based on the analysis of the onthogenesis of the dactylogyrid's haptor they postulate, that the haptor of these worms originally had 2 pairs of anchors and only 14 marginal hooks. The present paper contains data indicating that different representatives of the Dactylogyridea have 14-18 marginal hooks. Author put forward a suggestion, that some group of dactylogyrids originally did not have the anchors.
authors: P I
authors: PI
authors: Gerasev
mesh_terms: D000818:Animals; D017859:Esocidae / Q000469:parasitology; D005393:Fish Diseases / Q000469:parasitology; D005399:Fishes; D014200:Trematoda / Q000033:anatomy & histology / Q000145:classification*; D014201:Trematode Infections / Q000469:parasitology / Q000662:veterinary