Slender perennial with long rhizome. Culms rigid, terete, 1–3-noded, striate, glabrous, smooth, 20–90 cm high, 1.0–2.0 mm diam. Leaves basal and cauline; blade reduced to short erect flattened mucro; sheath straw-coloured to pale reddish or grey-brown, dull. Inflorescence oblong to ovate in outline, narrow, erect, 1–8 cm long, to 1 cm diam.; lowest involucral bract shorter than inflorescence. Spikelets few, 1-flowered, 3–6 mm long; glumes 4 or 5, acute to long-acute, red-brown to grey-brown, margins glabrous, keel minutely scabrous; fertile glumes 3–5 mm long. Nut obovoid to globose, smooth with scattered pits, hispid at apex, shining, dark red-brown to black, 2.3–3.0 mm long, 1.5–2.0 mm diam. Flowers spring–summer.