Plants not cespitose. Culms obtusely angled, 20–75 cm, glabrous. Leaves: basal sheaths red-brown; sheaths of proximal leaves glabrous, fronts lacking spots and veins, entire, apex U-shaped; blades 3–5 mm wide. Proximal bract subequal to inflorescence, 2–3 mm wide. Spikes erect; proximal 4–7 spikes pistillate, 4–9 cm × 3–4 mm, base attenuate; terminal 1(–2) spikes staminate. Pistillate scales red-brown or black, shorter than or equaling perigynia, apex acute, awnless. Perigynia ascending, olive-green, veinless, distended by and tightly enclosing achenes, ellipsoid or obovoid, 1.5–2.1 × 0.9–1.4 mm, dull, apex rounded, glabrous; beak green, 0.1–0.3 mm, orifice oblique. Achenes not constricted, dull. 2n = 68.