The semiterrestrial leech Haemopis elegans Moquin-Tandon, 1846 is widely distributed across Europe, though its eastern range limit remains poorly defined. This study examines the hypothesis that environmental conditions east of the Lviv region in Ukraine are unsuitable for the establishment of H. elegans, resulting in its observed range limit. Specimens of H. elegans were collected from Pohulianka Park in Lviv, western Ukraine, and their morphological characteristics were examined. In addition, a specimen from Argentr & eacute;, France, was included in the study. Molecular phylogenetic analysis was performed using mitochondrial DNA markers (cytochrome c oxidase subunit I) to confirm species identity, assess genetic diversity, and reveal phylogenetic relationships within the species. To predict the species' potential distribution under current environmental conditions, species distribution modeling was applied using occurrence records and key environmental variables. Morphological analysis confirmed the distinguishing features of H. elegans, such as body coloration and reproductive system traits, in comparison to the related and sympatric H. sanguisuga (Linnaeus, 1758). Our findings reveal distinct genetic differences among populations within the species' range, including the identification of new haplotypes in Ukraine and France. Both morphological and molecular data support the co-occurrence of for H. elegans east of its known range, while field surveys and genetic data confirm its absence or discontinuity in those areas.

Notwithstanding the genus Italobdella has been hypothesized to have doubtful taxonomic value, we decided to update its diagnosis by describing the new species – Italobdella bieleckii sp. n. The leeches were collected from the stony bottom along the shore of the Danube River in Slovakia. In the study, we implemented the model of leech body form and the set of external and internal morphological characters to present the similarity of the new species to the other fish leeches. As a result, we were able to construct the key for determining leeches belonging to the genus Italobdella hoping that the species could be found and determined by other researchers. This would enrich our knowledge about the actual distribution of these leeches and strengthen their systematic position in the genus.

This article concerns the first mention in France of Piscicola pojmanskae Bielecki, 1994, a leech new for France, in five samples from hydrobiologic survey, located in the departments of Deux-Sevres, Loire-Atlantique, Maine-et-Loire and Mayenne. Determinations are based on morphological and anatomical characters.