First record of Eustrongylides excisus (Dorylaimea: Dioctophymatidae) in fish of the Rybinsk reservoir.
The data on the finding of Eustrongylides excisus in the Rybinsk Reservoir (Yaroslavl oblast, Russia) are presented. Larvae-IV were recorded in 2015 in ruff. The appearance of this nematode in the reservoir is associated with the expansion of the range of cormorant, its main definitive host. E. excisus is one more parasite species exhibiting northward expansion in the Volga Basin.