CONTRIBUTIONS TO THE BIOLOGY OF DINA SKETI GROSSER & PEŠIĆ, 2014 (HIRUDINEA: ERPOBDELLIDAE)

Abstract

The known range of the species Dina sketi Grosser & Pešić, 2014 (Hirudinea: Erpobdellidae) includes several springs in the Cvrcka and Crna Rijeka basins (Republic of Srpska, Bosnia and Herzegovina). The biology of these leeches is insufficiently known. The aim of this paper was to present new knowledge about their ecology and reproductive biology, based on data collected in the springs of the Crna Rijeka basin. The analyzed parameters included characteristics of the biotope and macrozoobenthos assemblages of the studied springs, as well as characteristics of diet and the cocoons of D. sketi. The features of the biotope partially fit into the known range for this species. D. sketi is the only species of leech found in macrozoobenthos of the study area, where it is represented by less than 1%. The amphipod crustaceans and hydrobid gastropods are the most abundant members of the analyzed macrozoobenthos assemblages. The analysis of contents of the digestive tract revealed that these leeches prey on aquatic and terrestrial invertebrates. It seems that leeches prefer amphipods in their diet. All previous knowledge about the reproductive biology of D. sketi was based on description of their reproductive system. This paper presents the morphology and morphometric properties of the cocoons. They are “kiwi-shaped”, 4.60–8.82 mm in length and 3.19–6.38 mm width.