Perennial, 30-100 cm. Rhizome covered by grey-brown, finally fibrose scales. Stem erect or base ascending, obtusely or sharply trigonous, finely papillose. Leaves less than 1/2 of stem length; sheaths 30-80 mm, yellowish to grey-brown, margin of scarious side concave; ligule l-1.5 mm, arch twice as high as wide; blades 4-12.5 mm wide, abruptly pointed, flat, soft, apex slightly scabrious. Inflorescence of 1-2 male or gynecandrous spikes above and 2-4 female, nodding or drooping spikes below, overlapping or lowest remote, long-pedunculate, peduncle often rebranching. Bracts up to equalling inflorescence, sheaths to 40 mm. Male spikes 15-25 mm, from fusiform to slightly clavate, black-brown to brown; male glumes 4.4-4.6 x 0.8-1.1 mm, ovate to obovate, acute or with mucro up to 0.2 mm, brown, margins narrowly scarious. Female spikes 12-45 x 5-10 mm, cylindrical or ellipsoid, almost black, peduncles up to 90 mm; female glumes 3.8-6 mm, ovate or elliptic, acute or with barbed arista up to 3 mm, black-brown, margins narrowly scarious; utricles 5-6 x 1.5-1.7 mm, narrowly ellipsoid, smooth or papillose, black-brown, beak 1-1.5 mm, cylindrical, ostiole oblique, margins widely scarious. Stigmas 3. Nut 1.4-2.2 x 0.8-0.9 mm, including persistent style base and stipe, ellipsoid or fusiform, trigonous, light-brown to grey-brown, finely reticulate with papilla in each areole.