Chaetomargoreicheia in Croatia – on the discovery of a new eyeless scaritine ground beetle species

Abstract

Recently established genus Chaetomargoreicheia Margini & Bulirsh, 2005 (Scaritinae: Clivinini) includes endemic hypogean ground beetles found only in the Dinaric Alps (near Adriatic Sea coast). So far, this genus consisted of two species, one from Montenegro – C. lakotai (Magrini & Bulirsch, 2005) and another from Bosnia and Herzegovina – C. zoufali (Reitter, 1913). As a result of multiple cave explorations in the region of Dalmatia conducted over recent years, we found a single specimen of the first representative of the aforementioned genus in Croatia. The only specimen found is a male, which allowed us to carry out detailed morpho-anatomical comparisons with other known congeners. Since it is clearly separated from the most related taxa, we have realized that we have a species unknown to science and described it as C. gljevensis Ćurčić, Pavićević, Vesović & Rađa, 2018. It has been collected by hand in the Jama u Ljučici Cave, village of Gljev, near Sinj, on the southwestern slopes of Mt. Kamešnica. The three Chaetomargoreicheia stenoendemic species are for sure among the rarest known ground beetles based on the number of specimens collected (three in total). The new species has a long body, no sublateral pronotal discal setae and 27-28 small teeth on each lateral elytral margin. The Dinarides are definitely one of the world’s underground biodiversity hotspots and our finding confirms the high level of endemism present in the local entomofauna.