Perennial, 10-25 cm. Rhizome c. 1.5 mm diam., covered with grey, soon disintegrating scales; creeping stolons thinner. Stem sharply trigonous above, edges mostly scabrous. Leaves c. 2/3 of stem length; sheaths 15-40 mm, reddish-brown, glossy, fibrous with age; ligule to 0.2 mm, scarious, margin ciliate, straight; blades 1.5-3 mm wide, flat, keeled, both sides papillose or asperous. Inflorescence of 1(-2) male or gynecandrous and 1-3 female spikes. Lowermost bract much longer than its spike, with sheath to 12 mm. Male spikes 10-23 x 2-3 mm, fusiform or club-shaped, brown, male glumes 4.4-5.7 x 1.4-1.6 mm, ovate or elliptic, obtuse or acute, reddish brown with scarious margins. Female spikes 8-18 x 3-5 mm, ellipsoid, cylindrical or globose, erect, lowest usually with peduncle to 15 mm; female glumes 3.3-4.6 x 2-2.1 mm, ovate, acute or with mucro up to 0.5 mm, reddish brown, margins widely scarious; utricles 3.8-4.6 x 1.3-1.6 mm, ellipsoid, greenish or yellowish brown, glossy, slightly inflated, coriaceous, upper part occasionally setose, beak 1-1.2 mm, cylindrical, truncate or oblique, brown or reddish brown, ostiole margin scarious. Stigmas 3, style base slightly swollen. Nut c. 2.7 x 1.1-1.3 mm, obovoid, trigonous, yellowish, finely reticulate with a small papilla in each areole.