Tufted perennial with a short thick rhizome and stems usually set in a row, or stems solitary; stems 20–60 cm long and 1.5–5 mm thick, triangular, glabrous, the basal part covered with leaf-sheaths. Leaves 5–30 cm long and 2–8 mm wide, flat, scabrid on margin and midrib; leaf-sheaths grey to dark purple (or black on old stem), rather lax. Inflorescence a compound umbel-like anthela 5–25 cm wide and 3–25 cm long; major branches 5–15, 1–18 cm long; secondary and tertiary branches short or spikes sessile. Spikes 2–4 x 1-4 cm, spikelets rather loosely set and often spreading at an angle of 90°. Spikelets 7–20 x 0.5–1 mm (or 1–2 mm wide with glumes spreading), linear or zigzag when glumes spreading, often breaking at its base with the glumes and nutlets persistent on its rhachis, 10–20-flowered; rhachis with a wide transparent wing on two sides. Glumes 1.7–2.6 mm long, oblong-elliptic, straw-coloured, light to dark reddish brown with a 3–5-nerved often green or paler keel; apex obtuse with a reddish brown or transparent margin into which the keel does not reach; glumes placed rather distant, falling off with the nutlet or persistent until the whole spikelet falls as one unit. Style 3-branched. Nutlet 1.4–1.7 x 0.4–0.5 mm, narrowly elliptic with short apiculus, yellowish and almost smooth when young, grey with a metallic shine and minute papillae in longitudinal rows when mature.