The incidence of the anomaly P syndrome in water frogs (Anura, Ranidae, Pelophylax) from the Middle Volga River (Russia)

The anomaly P is a widespread morphological anomaly, which occurs in some groups of amphibians, caused by the trematode parasite Strigea robusta (Digenea: Strigeidae). This has been previously recorded water frogs genus Pelophylax and toads genera Bufo Bufotes . includes symmetrical polydactyly cases as mild attenuated form complex syndrome, severe strong deformations hindlimbs forelimbs. 3-host life cycle using planorbid mollusks first intermediate hosts, amphibian larvae second anatid birds definitive hosts. Herein, we described new records syndrome from northeastern parts their ranges. Symmetrical (as syndrome) was found 30 individuals three species seven localities: 25 P. lessonae four waterbodies, ridibundus one individual esculentus In Gusevo pond, with were found. record reliably identified hybridogenetic edible ( ) that have nature. Additionally, provided data about occurrence prevalence S. taken two bodies where anomalous