Water-gliding
Guides
Steninae
Water Skater Beetles
Steninae is a megadiverse subfamily of rove beetles (Staphylinidae) containing over 3,000 species worldwide, primarily in the genera *Stenus* and *Dianous*. Members are characterized by their unique prey-capture apparatus: a protrusible elongated labium with paraglossae modified into adhesive pads that eject via haemolymph pressure to capture springtails and other small arthropods. Many species exhibit remarkable water-gliding behavior using gland secretions that reduce surface tension. Adults are diurnal, visually oriented predators of moist habitats.
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.
Stenus annularis
Stenus annularis is a species of rove beetle in the subfamily Steninae, described by Erichson in 1840. The genus Stenus is notable for its members' ability to glide on water surfaces using specialized gland secretions that reduce surface tension. Some species in this genus also employ a unique hunting mechanism involving the ejection of mouthparts using blood pressure to capture small invertebrate prey. Stenus annularis has a broad distribution across North America, with records from Canada and the United States.
Stenus comma
Stenus comma is a rove beetle in the family Staphylinidae, notable for its highly specialized predatory behavior. The species employs a unique hunting mechanism using pygidial gland secretions to capture springtails (Collembola). It can eject a viscous, sticky secretion as a droplet on an extendable terminal filament to 'shoot' at prey, or apply the secretion directly during ambush. The beetle demonstrates flexible hunting strategies that adapt to different prey types and defensive capabilities. This species has a broad distribution across the Northern Hemisphere, including Europe, Asia, and North America.
Stenus femoratus
Stenus femoratus is a species of rove beetle in the subfamily Steninae, first described by Thomas Say in 1831. Like other members of the genus Stenus, it possesses specialized labial structures that can be everted using blood pressure to capture prey. The species is broadly distributed across eastern and central North America, with records from Canada and numerous U.S. states.
Stenus latissimus hatchi
Stenus latissimus hatchi is a subspecies of rove beetle in the family Staphylinidae, subfamily Steninae. Like other members of the genus Stenus, it possesses the specialized labial apparatus that allows some species to capture prey using adhesive secretions. The subspecies occurs across a broad transcontinental range spanning northern Eurasia and western North America. As a member of the Steninae, it is associated with moist habitats near water bodies where the water-gliding behavior characteristic of many congeners may be expressed.
Stenus pinguis
Stenus pinguis is a species of rove beetle in the subfamily Steninae, first described by Casey in 1884. The species belongs to a genus renowned for its remarkable water-gliding ability, enabled by specialized gland secretions that reduce surface tension. As a member of Stenus, it likely employs the characteristic labial prey-capture mechanism using eversible mouthparts with adhesive paraglossae to capture small invertebrate prey. The species has been recorded across western North America from Canada to the United States.
Stenus pubescens
Stenus pubescens is a species of rove beetle in the family Staphylinidae, subfamily Steninae. It is one of numerous species in the large genus Stenus, which is characterized by distinctive adaptations including the ability to glide on water surfaces using specialized gland secretions. The species has a Holarctic distribution, occurring across much of Europe, northern Asia, and North America. Like other members of the genus, it is a predator of small invertebrates.