Tufted annual or possibly perennial. Culms erect, terete, striate, nodeless or 1-noded, 3–25(–55) cm high, 0.5–1.2 mm diam. Leaves with blade to 15 cm long; sheath straw-coloured to dark red-brown, striate, ± shining; mouth glabrous; ligule present. Inflorescence of 1 loosely hemispherical cluster of 6–16 spikelets, usually with 1–4 clusters below, erect, 1–15 cm long; lowest involucral bract to 17 cm long. Spikelets narrow-ovate, acute, 1–3-flowered, 2.5–7.5 mm long; glumes 4–6, lowest 2–4 empty, acute, red-brown to blackish, shining, with glabrous margins, midvein often scabrous; fertile glumes 2.0–5.5 mm long; hypogynous bristles 5 or 6, not plumose, shorter than or equalling nut. Nut trigonous, obovoid to subglobose, 3-ribbed, reticulate-pitted to trabeculate, glabrous, shining, whitish, 1.0–1.2 mm long, 0.6–0.8 mm diam. Flowers spring–summer.