Italobdella bieleckii sp. n. (Hirudinea: Piscicolidae), a new leech species from the Danube in Slovakia

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.

Sucking of human blood by Placobdella costata (O. F. Müller, 1846) (Hirudinida: Glossiphoniidae): Case study with notes on body form

Four events of Placobdella costata sucking human blood are described.Human blood was sucked by both adult and juvenile specimens of P. costata.The feeding strategies of juveniles under parental care are presented.New data on juvenile specimens' body form are presented.Information on the potential role of mammals in dispersion and habitat preferences of leeches P. costata is considered.

Hirudins and hirudin-like factors in Hirudinidae: implications for function and phylogenetic relationships

Haematophagous leeches express a broad variety of bioactive factors that are released from the salivary gland cells into the wound of a host during feeding. Among these, hirudin is probably the best studied factor and, moreover, the only one that has successfully made the transition from nature to clinical use. Many components of the leech saliva still remain either poorly characterized or yet completely unknown. Only recently, a new class of leech-derived factors has been discovered in Hirudo medicinalis, the hirudin-like factors (HLFs). HLFs comprise typical structural features of hirudin but lack others. We were able to verify the expression of HLFs not only in two additional species of the genus Hirudo, but also in Hirudinaria manillensis. Various phylogenetic analyses based on gene and protein sequences support a sister group relationship between hirudins and HLFs. Although potential molecular targets of HLFs remain unknown, the presence of multiple isoforms in individual leeches of different genera points to key functions in the regulation of several processes associated with the blood-sucking life style of leeches.