Report of the largest known occurrence of morphological anomalies in a population of an endemic ground beetle: Carabus (Chaetocarabus) lefebvrei lefebvrei Dejean, 1826

Abstract

We report the largest known occurrence of morphological anomalies in adults of a species of ground beetle. Specimens of a population of Carabus (Chaetocarabus) lefebvrei lefebvrei Dejean, 1826 were collected using pitfall traps in 2019 in a stand dominated by chestnut (Castanea sativa), near a protected area in Northeastern Sicily. More than 13% of the trapped specimens showed morphological anomalies in the pronotum or elytra. The anomalies ranged from the presence of tumours, missing or fused elytral striae, and deformed elytra to incomplete pronotum and difference in shapes of legs. These anomalies were compared with those of eight specimens collected in Eastern Sicily (Etna, Nebrodi and Peloritani). We recorded slightly more females than males with anomalies. The occurrence of so many morphological anomalies in adult beetles near a protected area is alarming.