Drusus sharrensis sp. n. (Trichoptera, Limnephilidae), a new species from Sharr National Park in Kosovo, with molecular and ecological notes.

In this paper we describe Drusus sharrensis sp. n., from the Sharr Mountains in Kosovo. Males of the new species are morphologically most similar to Drusus krusniki Malicky, 1981, Drusus kerek Oláh, 2011 and Drusus juliae Oláh, 2011 but differ mainly in exhibiting (1) a differently shaped spinose area on tergite VIII; (2) intermediate appendages anteriorly curved in lateral view with broad tips in dorsal view; (3) inferior appendages with a distinct dorsal protrusion in the proximal half. Females of the new species are morphologically most similar to Drusus krusniki, Drusus kerek, Drusus juliae, and Drusus plicatus Radovanovic, 1942 but mainly differ in (1) segment X that is longer than the supragenital plate with distinctly pointed tips; (2) supragenital plate quadrangular with a distinct round dorsal protrusion; (3) a vulvar scale with a small median lobe. Results of phylogenetic species delimitation support monophyly of Drusus sharrensis sp. n. and recover it as sister to a clade comprising (Drusus pelasgus Oláh, 2010 + Drusus juliae + Drusus arbanios Oláh, 2010 + Drusus plicatus + (Drusus dacothracus Oláh, 2010 + Drusus illyricus Oláh, 2010)). The new species is a micro-endemic of the Sharr Mountains, a main biodiversity hotspot in the Balkan Peninsula. Main threats to the aquatic ecosystems of this part of the Balkan Peninsula are discussed.