Ground beetle (Coleoptera: Carabidae) communities and microhabitat diversity in a mountain village house yard – a case study from the Western Rhodope Mountains in Bulgaria

This study explores the ground beetle (Coleoptera: Carabidae) diversity from an uncultivated house yard in a mountain hamlet in the Western Rhodope Mountains in southern Bulgaria. The sampling site was located at an altitude of 1340 m. A total of 2512 carabid specimens of 76 species were collected with only six pitfall traps between May 2016 and April 2021. They belong to 31 genera, 13 tribes, 21 zoogeographical categories and 15 life forms. Two species (Olisthopus rotundatus and Ophonus brevicollis) are new for the Rhodope Mountains. The findings reveal new highest altitude records for two species (Ophonus brevicollis and Philorhizus notatus). Along with the typical montane forest fauna, many ecotone and open habitat species were found. Nevertheless, carabid life forms and wing morphology structure indicate a stable environment in comparison with other regions in Bulgaria. Furthermore, this research demonstrates that even small natural habitat patches can keep a remarkable carabid diversity. Over the five-year study period, the carabid fauna in the studied house yard experienced some, both qualitative and quantitative, impoverishment, indicating some ecological “exhaustion”.