Genus Stenopsocus Hagen

Stenopsocus Hagen, 1866: 203. Type species: Psocus immaculatus Stephens, original designation.

Diagnosis. Adults of medium size, with well developed long wings. Body length from postclypeus to wing tip 4–7 mm. Antenna 13 segments, slightly longer than body. Lacinia narrowing toward apex. Tarsi with two segments, pulvillus broad, and tarsal claw without preapical tooth. Wings narrowly elongate. Forewing with setose anterior margin and single-row setae on all veins except for Cu2, Cu2 with setae or not; pterostigma narrowly elongate, connecting with Rs by a crossvein; Rs and M proximally fused for a distance; M three-branched; ap cell trianglar, anteriorly connecting with M by a crossvein. Hindwing much smaller than forewing, with anterodistal margin setose between branching of Rs. Male hypandrium posteriorly convex; phallosome with two pairs of parameres. Female subgenital plate posteriorly convex; dorsal valve and ventral valve sclerotized, narrow, proximal portion of dorsal valve broad; external valve reduced; spermathecal sac generally pear-shaped.

Distribution. The genus is widely distributed in all main zoogeographical realms of the world.