The first molecular characterization of the genus Hirudo on the territory of Serbia: estimation of endangerment

Abstract

Several recent morphological studies of the genus Hirudo indicated that only Hirudo verbana is present in Serbia, while Hirudo medicinalis is completely absent. In order to test this hypothesis, specimens of medicinal leech from Serbia are analyzed for the first time by the method of DNA identification. The results show that individuals belonging to the species H. medicinalis are absent on the territory of Serbia, where only specimens of the sister (congener) species H. verbana can be found instead. All of the analyzed specimens can be related to five haplotypes. Two of the haplotypes are previously known from Ukraine, while three are newly discovered. It follows that genetic differentiation into eastern and western clades of the species H. verbana is unrealistic. Much more detailed sampling throughout the entire area is needed in order to establish the precise distribution of haplotypes. Factors posing a threat to both individual populations and the species as a whole are also considered as a basis for undertaking conservation measures for preservation of the species H. verbana. Such measures are necessary in view of the fact that for the past 8 years, H. verbana has been exported from Serbia to Western European countries instead of H. medicinalis (which does not live on the territory of Serbia). On the basis of the obtained results, the degree of threat to the species H. verbana is defined and preliminary protective measures are proposed for the conservation of this endangered species of aquatic invertebrate.