PHYLOGENETIC RELATIONS BETWEEN SPECIES OF THE GENUS COTYLURUS AND ITS POSITION IN THE SYSTEM OF THE TREMATODE FAMILY STRIGEIDAE

Cladistic analysis of phylogenetic relations between species of the genus Cotylurus was carried out. The obtained data show that the genus is homogenous and monophyletic and serve as a basis for unification of the genera Cotylurus and Cotylurostrigea as the species assigned to the latter do not form a monophyletic branch. The same analysis of separation phylogenetic relations between the genera of the family Strigeidae has confirmed the validity of separation of the genus Pseudapatemon into a distinct subfamily. The other genera form two distinct monophyletic groups differing in the structure of copulatory organ. It seems to be expedient to accord the above groups the rank of subfamilies: Cotylurinae (the genera Cotylurus and Ichthyocotylurus) and Strigeinae (all the other genera excluding Pseudapatemon).