Carabus (Tomocarabus) bessarabicus Fischer von Waldheim, 1823 (Coleoptera: Carabidae)—New Steppe Element for the Bulgarian Fauna from the Karst Refugium of the Chepan Planina Mt.

Abstract

During a study of the distribution and status of Carabus hungaricus Fabricius, 1792 (Coleoptera: Carabidae), with pitfall traps exposed between November 2021 and April 2022, immediately south of Petrovski Krast Peak (1206 m a.s.l.) in the Chepan Planina Mt., at 1188 m a.s.l., the rare and stenotopic steppe species Carabus bessarabicus Fischer von Waldheim, 1823, was found for the first time in Bulgaria and the European Union. In October 2022, elytra of both species were also found by handpicking in the same area. The coexistence of these two specific and rare steppe species has been recorded only in few localities in Ukraine and Russia and in no EU country. This finding is also very interesting given the high conservation status of Carabus bessarabicus, the significant remoteness of its newly established locality (more than 1200 km) from its previously known range, and its strong south-westward drift. The species is used as a bioindicator for the anthropogenically uninfluenced steppe environment, which can also probably be applied in Bulgaria. The establishment of this first record for the EU also implies an increase in the conservation status of the species through its inclusion in the Union-wide conservation documents and ecological networks.