[Classification of nematode parasites of vertebrate animals]

The authors give the analysis of the best known systems of nematodes, parasitizing vertebrates. The classifications of Chitwood (1933, 1937); Skrjabin et Schultz (1940) and Chabaud (1974) are discussed. A new variant of the system of the mentioned nematode groups is proposed, the classification of Chabaud being assumed as its basis. In the subclass Adenophorea the authors distinguish two orders--Trichocephalida and Dioctophymida. The subclass Secernentea includes according to Chabauds system five orders: Rhabditida, Strongylida, Oxyurida, Ascaridida and Spirurida. Two suborders--Ascaridina and Heterakina are distinguished in the order Ascaridida, three suborders--Spirurina, Cammallanina and Filariina--in the order Spirurida. The suborders Gnathostomatina and Cucullanina are admitted to be not enough valid. Both these groups are considered as superfamilies in the new variant of classification. A conception of the close phylogenetic relationships between the orders of the subclass Seurina, Cammallanina and Filariina--in the order Spirurida. The suborders Gnathostomatina and Cucullanina are admitted to be not enough valid. Both these groups are considered as superfamilies in the new variant of classification. A conception of the close phylogenetic relationships between the orders of the subclass Seurina, Cammallanina and Filariina--in the order Spirurida. The suborders Gnathostomatina and Cucullanina are admitted to be not enough valid. Both these groups are considered as superfamilies in the new variant of classification. A conception of the close phylogenetic relationships between the orders of the subclass Secernentea is championed. The authors believe that the historical development of the representatives of this nematode group occurred from the rabditiform worms towards the strictly specialized parasitic forms, which are met in the order Spirurida. The representatives of the order Rhabditida are the most closely related to the ancestral forms of the subclass Secernentea.