Protrusible-labium
Guides
Stenus
rove beetles, water-gliding rove beetles
Stenus is a genus of semiaquatic rove beetles comprising approximately 3100 described species, making it one of the largest genera in the animal kingdom. These beetles are specialist predators of small arthropods, particularly Collembola. They possess distinctive adaptations including a protrusible adhesive labium for prey capture and pygidial gland secretions that enable rapid water surface locomotion via the Marangoni effect. The genus occurs worldwide across diverse habitats from aquatic margins to terrestrial leaf litter.