Leafy tufted annual. Culms weakly erect, terete, striate, nodeless, 2–20 cm high, 0.5–1.5 mm diam. Leaves with blade to 11 cm long; sheath straw-coloured to red-brown, striate, dull; mouth glabrous; ligule present. Inflorescence narrow, erect, 2–22 cm long, with 2–6 nodes, each with 1–5 spikelets; lowest involucral bract to 14 cm long. Spikelets narrow-ovate, acute, 2–6-flowered, 6–12 mm long; glumes 4–9, lowest 1 or 2 empty, acute, straw-coloured to dark red-brown, ± shining, with glabrous margins and often scabrous midvein; fertile glumes 4–8.2 mm long; hypogynous bristles absent or minute. Nut trigonous, ellipsoid, prominently 3-ribbed, reticulate-pitted, glabrous, ± shining, greyish to black-spotted or evenly pale brown, 1.2–2 mm long, 0.8–1 mm diam. Flowers spring–early summer.
LoM, MuM, Wim, GleP, VVP, VRiv, MuF, GipP, WaP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, HSF, HNF, MonT. Also SA, Qld, NSW, ACT, Tas. In seasonally wet places.
