Plsnts tufted, wiry perennials up to 100 cm tall. Rames 3-12 cm long, gently curved. Sessile spikelets 6-16 cm long, laterally compressed; lower glumes narrowly oblong-elliptic, thinly coriaceous with bifid membranous tip up to 1/3 the length of the body, 2-keeled, concave between the keels,with 2-3 closely spaced veins adjacent to each keel; upper lemmas awned; awns 2-4 cm long, columns minutely ciliolate along the edges of the corils. Pedicellate spikelets 6-10 mm long, ciliate, the lower glumes with a midvein and 2-3 veins adjacent to each keel.
Sehima nervosum grows on rocky hillsides and in desert grasslands at 1200-1500 m. It is known from region N1 of the Flora of Somalia and from eastern tropical Africa, Ethiopia and the Sudan southwards to Mozambique and eastwars through Arabia to China and Australia.