This paper presents an analysis of helminth diversity in green frogs of the Pelophylax esculentus complex from twelve provinces of the Middle Volga region (European Russia). The study relies on the occurrence dataset recently published in GBIF in the form of a Darwin Core archive. The database contains current information on helminth occurrences in these anurans, comprising records from our long-term helminthological survey conducted in 1997–2025. Our database includes 13,634 helminth occurrence records for three Pelophylax species residing in the Middle Volga region. Each helminth occurrence record is linked to georeferenced data. A total of 43 parasite species are documented in the dataset, including 29 species of trematodes, one cestode, 11 nematodes, and two acanthocephalans. The greatest helminth diversity was recorded in Pelophylax ridibundus (42 species), which is the most widespread and abundant amphibian species in European Russia. The helminth fauna is less diverse in Pelophylax lessonae (32 species) and their hybrid, Pelophylax esculentus (25). Most helminth species found in green frogs within the studied area belong to the Palearctic faunal complex (29 species). Five helminth species each have European and Holarctic distributions, while four species are cosmopolitan. Of the 43 species of helminths found, three (Alaria alata, Spirometra erinacei, Ascarops strongylina) are of medical and veterinary importance as causative agents of parasitic zoonoses, posing a threat to domestic animals and humans.
Kirillov et al. (Thu,) studied this question.