Rediscovery of the "extinct" blind ground beetle (Coleoptera: Carabidae: Trechinae)

The blind ground beetle Ishikawatrechus intermedius (Coleoptera: Carabidae: Trechinae), called Kadotamekurachibigomimushi in Japanese, was first found in 1952 in the cave Ochi-do, Kochi Prefecture, Japan. However, this cave and a large part of the surrounding hill were destroyed by limestone mining in the 1970s. Because most species of blind ground beetles are restricted to specific caves or cave systems, I. intermedius has been considered endemic to very narrow areas of the cave Ochi-do and the upper hypogean zone around the cave. Therefore, I. intermedius was considered to have become extinct. In this study, during 2011-2015, we collected ten individuals of a blind ground beetle, which appeared to be I. intermedius, from the upper hypogean zone, approximately 0.3-1.0 m below ground, in the southern part of the type locality. A comparison with type specimens indicated that the individuals were indeed I. intermedius. Therefore, we conclude that I. intermedius survives in the upper hypogean zone near the type locality. The results of this study will be useful for quickly establishing conservation measures for threatened or vulnerable species of Trechinae beetles.