Placobdella nabeulensis sp. nov. (Hirudinea: Glossiphoniidae), a new glossiphoniiform leech from Palearctic North Africa

Abstract

Herein, we describe a new species of turtle blood-feeding leech, Placobdella nabeulensis sp. nov. from Palearctic North Africa (Tunisia and Algeria). The new species is described based on detailed morphological analyses using light and scanning electron microscopes. Apart from the detailed morphology of the atrium, morphological features alone do not sufficiently separate the species from congeners due to the absence of distinct diagnostic characters. Therefore, we turned to molecular data to better distinguish this new species from other members of the genus and establish a basis for its genetic separation. Four DNA fragments were successfully amplified, including mitochondrial COI and 12s rDNA, as well as nuclear 28S rDNA and histone H3. We then provided the molecular descriptor of the taxon, based on redundant diagnostic nucleotide combinations in DNA sequence alignment within the Folmer region. Results of the phylogenetic analysis and species delimitation methods (ABGD, ASAP, and bPTP) based on the COI locus support the species rank of the Tunisian-Algerian Placobdella. The new species is most closely related to the European species Placobdella costata (Fr. Müller, 1846) and the present study indicates that Placobdella nabeulensis sp. nov. has likely been confused with the European counterpart in several previous studies.