Annual, forming small tussocks, 2.5-20 cm. Roots fibrous. Stem 0.2-0.3 mm diam., terete, smooth, green or yellowish green. Leaves reduced, usually with one complete leaf at stem base; sheaths to 20 mm, lowest bladeless, scarious, often reddish; longest much overtopping lower ones, yellow green or lower part often reddish, mouth wide, scarious, oblique; blades 1-20 mm, as wide as stem, channelled, smooth, apex obtuse. Inflorescence 1-2 sessile spikes; bract as long as spike or to 10 mm, basal part (sheath) scarious, keeled, often reddish brown. Spikes 2-5 mm, globose or ovoid, with up to c. 30 glumes; when two spikes, lower with obtuse, glume-like prophyll; glumes 1.3-1.5 mm, cymbiform, keeled, midnerve strong, at first green, smooth, barely reaching obtuse apex, sides with 3-5 fine nerves, reddish brown or sometimes colourless, scarious. Stamens 2; stigmas 3. Nut 0.7-0.9 x 0.5-0.6 mm, with wide stipe and narrow beak c. 0.1 mm, obovoid, unequally bi-convex, brown, sometimes whitish, trabeculate with pronounced longitudinal ribs.