Beneath the Ground: Phylogenetic Position and Morphological Characteristics of Ityogonimus ocreatus (Goeze, 1782) (Digenea: Brachylaimidae), a Parasite of European Moles

The genus Ityogonimus currently comprises three recognized species: Ityogonimus ocreatus, Ityogonimus lorum, and Ityogonimus scalopi. The type species of this genus, I. ocreatus, parasitizes European moles. Despite the widespread distribution of the genus Ityogonimus, molecular studies on these parasites have not yet been conducted. The phylogenetic position of this genus remains unresolved. In this study, we present the first molecular phylogenetic data on Ityogonimus ocreatus from the European mole in Russia based on partial sequences of its LSU (28S rRNA) gene, alongside a comprehensive morphological and morphometric description of this trematode. Additionally, we obtained sequences of the nuclear ITS2 region and mitochondrial cox1 gene. The morphological characteristics of the flukes examined indicate that they belong to the subfamily Ityogoniminae within the family Brachylaimidae. The molecular data obtained demonstrate that the genus Ityogonimus is clearly distinct from other members of the Brachylaimidae. Further comprehensive analyses on brachylaimids, including multilocus approaches, are required to clarify the appropriate classification of the constituent species within the family.