The possibility of using helminths to analyze the faunogenesis of amphibians in the Volga River basin is considered, using geographically isolated subspecies of the green toad Bufotes viridis (Laurenti, 1768) as an example. A depleted helminth composition was established in the “western” subspecies B. v. viridis (Laurenti, 1768); the presence of cestodes and acanthocephalans was noted in the “eastern” subspecies B. v. sitibundus (Pallas, 1771) only.
