Velleius dilatatus

Description

The rove beetle Velleius dilatatus lives together with the European hornet Vespa crabro crabro. Velleius dilatatus is up to 26 mm long. It feeds on detritus produced by the hornets (an example of commensalism). The beetles cannot survive without the hornets themselves, even if there is enough detritus present. It finds hornet nests by its very good sense of smell. Most nests contain an average of ten V. dilatatus.