Sand-binding perennial, 15-35 cm. Rhizome emitting subterranean stolons covered by dark, fibrous scales. Stem erect or ascending, 0.7-1.7 mm in diam., terete or obtusely trigonous, smooth, greyish green. Leaves from c. 1/2 of stem length to almost equalling it; sheaths 30-60 mm, greyish-brown, fibrous, old blades cut off by sand, often at one level; ligule c. 0.2 mm; blades 1.5-2.5 mm wide, channelled or involute, stiff, frequently falcate, long-attenuate, smooth or scabrous towards apex. Inflorescence compact, of 5-6, mostly androgynous spikes; proportion of male flowers per spike varies from few to the majority. Bracts glume-like, lower to length of their spike, amplexicaul. Male glume c. 6.2 x 1.4 mm, narrowly triangular, acute, light brown, with wide scarious margins. Female glumes 4.6-5 x 2-2.5 mm, cymbiform, acute or with arista up to 1.5 mm, light brown, margins widely scarious. Utricles finally much inflated, up to 25 x 12 mm, globose or elongate, membranaceous, many-nerved, smooth, glossy, with stipe c. 0.5 mm, beak 0.7-1.5 mm, conical or cylindrical, brown or scarious, ostiole oblique. Nut 2.9-3.1 x 2.3-2.7 mm, spherical, bi-convex, light brown, reticulate.