Morphological and molecular characterization of plagiorchiid trematodes (Plagiorchis: Plagiorchiidae, Digenea) from bats with redescription of Plagiorchis mordovii Shaldybin, 1958

Five Plagiorchis spp. parasitize bats in European Russia: Plagiorchis elegans, Plagiorchis koreanus, Plagiorchis mordovii, Plagiorchis muelleri, and Plagiorchis vespertilionis. Their identification is difficult due to a high morphological similarity. The morphological variability of these species is poorly studied. The taxonomic position of P. mordovii remains debatable. The purpose of our study was to analyse Plagiorchis spp. from European bats using a combination of morphological and molecular-phylogenetic approaches and to establish the taxonomic position of the problematic species P. mordovii. Plagiorchis spp. were shown to be variable morphologically and morphometrically both from various host species and from different specimens of the same species. We presented a new taxonomic key for identification of the Plagiorchis spp. from European bats, provided a complete description of Plagiorchis mordovii, and confirmed the validity and the generic affiliation of this species.