Materials on the fauna of multicellular parasites of Perca fluviatilis L. (Actinopterygii: Perciformes) (Saratov Reservoir)

The fauna of multicellular parasites of Perca fluviatilis (Peciformes) (2019, 2022) was studied at the site of the Saratov reservoir, located in the zone of influence of a large hydroelectric complex - the Zhigulevskaya HPP (a branch of PJSC RusHydro). 8 species of parasitic organisms were found. Infection of fish with alien parasites Apophallus muechlingi and Nicolla skrjabini was revealed. The trematode A. muechlingi, a specific parasite of Cyprinidae, occupied a dominant position in the perch macroparasite fauna. This process took no more than 19 years since the introduction of the alien mollusk Lithoglyphus naticoides, the first intermediate host of the parasite. The possibility of participation of invasive fish in the process of P. fluviatilis invasion by 5 parasite species is discussed. Species posing a potential danger to fish, carnivores and humans have been found. In particular, for the first time for P. fluviatilis in the Saratov reservoir, the acanthocephalan Pomphorhynchus laevis, the causative agent of fish pomphorhynchosis, was recorded.