Rhizome with rather thick stolons. Culms 60-90 cm tall, triquetrous, stout, stiff, smooth on lower part, scabrous on upper part, with red-brown and bladeless sheaths at base. Leaves nearly equaling culm, blades 3-10 mm wide, flat, usually plicate at base, with transverse septate nodes between veins, scabrous on veins and margins. Involucral bracts leaflike, longer than spike, not sheathed or lower involucral bract shortly sheathed. Spikes 4 or 5; terminal 1-3 male, approximate, clavate or narrowly cylindric, 2-4 cm, subsessile; remaining spikes female, rather remote, oblong or shortly cylindric, 2.5-3 × 0.6-1.5 cm, densely many flowered, shortly pedunculate. Female glumes red-brown, lanceolate or narrowly lanceolate, 4.2-5 mm, membranous, costate, apex subacute. Utricles stramineous or dark chestnut-brown, obliquely patent, slightly longer than or nearly equaling glume, oblong-ovate, inflated trigonous, 5-5.5 mm, glabrous, shiny, thinly 5-veined, base rounded, very shortly stipitate, apex gradually narrowed to a short beak, orifice emarginate. Nutlets broadly ovate, trigonous, ca. 2 mm, base shortly stipitate; style slender, base bent; stigmas 3, rather short. Fl. and fr. Jul-Aug.

Alpine wetlands, damp alpine grasslands; 2400-3700 m. Gansu, N Sichuan, Xinjiang [Afghanistan, India (Sikkim), Kazakhstan, Russia].