Distribution range

Up to now, two different species of the genus Aphaenopidius were known: the Kamnik eyeless ground beetle and the large eyeless ground beetle (Aphaenopidius treulandi). The latter was described in 1909, from a cave in Dobrovlje plateau. To our great surprise, a new species of this genus was found in 2018, more than 100 years after the genus was first described. The reason for such late discovery may lie in the fact that it was found 500 m below ground!

At first glance many cave beetles look alike – but a closer look at male genitalia reveals differences between species. With the use of molecular DNA analyses and identification of species-specific nucleotide sequences, new possibilities for species identification emerged. This also enabled determination of female and larval specimens, which could not be determined by traditional methods.

In both species of this genus, subspecies were described, which are only known from a single or a few caves. The rarity of these beetles is probably one of the main reasons that make them attractive to collectors. They set pit fall traps with smelly baits which do not only attract beetles but many other animals as well. As such traps are left in the caves for long periods, or even remain there forgotten, they can cause significant decline of local populations and present a serious threat to their existence.