Riffle-inhabitant
Guides
Psephenus
water penny beetles
Psephenus is a genus of water penny beetles comprising approximately 13 described species. Larvae are aquatic, highly flattened, and cling to submerged stones in streams using ventral sucking discs. Adults are terrestrial, do not feed, and aggregate near water for mating. The genus exhibits strong associations with stream riffles and turbulent water environments.