Genus Mesorhaga Schiner, 1868

Species of Mesorhaga are usually distinguished from other genera by the following features: Vertex deeply concave in males. Postpedicel nearly quadrangle in lateral view, arista-like stylus dorsal. Thorax with various acr and 5 dc. Scutellum with 2 pairs of sc, of which apical pair strong, basal pair weak. Tibiae without distinct dorsal bristle. Wing hyaline; M 2 absent, crossvein dm-cu nearly straight or straight. Seventh sternum absent or fused with seventh tergum. Epandrium cylindrical, elongated. Phallus and hypandrium long and thin; phallus level dorsally; hypandrium without lateral arm. Epandrial lobes usually expanded, oval, with strong lateral bristles at base. Surstylus with 3–4 short protuberances overlapping each other. Cercus usually curved, with strong lateral bristle(s) at base.

In comparison to Amblypsilopus, Chrysosoma, Condylostylus and Plagiozopelma, Mesorhaga is relatively poorly represented in the Himalayan region. Only three species of Mesorhaga have been reported, of which one is known found India and two found in China (Nyingchi of Tibet). A key to the three species is provided below.