Tufted perennial with very short rhizome. Culms trigonous, smooth, slightly swollen at base, to 50 cm high, 1.5 mm diam. Leaves not septate-nodulose, often as long as culms, 1–2 mm wide. Inflorescence simple, with 3–5 branches to 8 cm long; clusters spicate to subdigitate, broad-cylindric to obovoid, to c. 1 cm long, c. 5 cm diam.; involucral bracts leaf-like, 2 longer than inflorescence. Spikelets somewhat flattened, 6–20 per spike, 8–30 mm long, 1–1.5 mm wide inside view, 5–16-flowered; rachilla broadly winged, persistent, or spikelet felling as unit; glumes rather remote, somewhat appressed, with sides 1–3-nerved near keel, greenish tinged red-brown, 2.5–3.5 mm long; stamens 3; style 3-fid. Nut trigonous, narrow-obovoid to ellipsoid, yellow-brown to blackish, c. one-half as long as glume, 1.2–1.7 mm long, 0.5–0.7 mm diam. Flowers spring–summer.
MuM, Wim. Also Qld, NSW. Rare in Victoria, recorded in recent times only from seasonally inundated areas in the Jeparit and Natimuk areas (pre-1900 records exist from the Dimboola area).
The typical form of this species, found on the coast of Qld and NSW, is tall (to 50 cm), with glumes 2.8–3.5 mm long and mostly red-tinged, and nuts 1.5–1.7 mm long and c. 0.7 mm diam. The plants found in inland Victoria, Qld and NSW are smaller (culms to 25 cm high), with glumes c. 2.5 mm long and often with little or no reddish tinge, and nut c. 1.2 mm long, c. 0.5 mm diam. They may represent a separate taxon.
