Plants not cespitose. Culms obtusely angled, 3–15 cm, glabrous. Leaves: basal sheaths brown; sheaths of proximal leaves glabrous, fronts lacking spots and veins, apex U-shaped; blades epistomic, strongly involute, 1–2 mm wide, adaxially papillose. Proximal bract longer than inflorescence, 1–3 mm wide, spathelike at base and enclosing spike. Spikes erect; staminate 1(–2); pistillate 1–3; proximal pistillate spike 0.5–1.4 cm × 2–4 mm, base cuneate. Pistillate scales bright brown to dark purple-brown, 2–3.6 × 0.9–1.5 mm, wider than perigynia, midvein reaching apex, 1/5–1/2 the width of scale, apex acute, rarely acuminate, mucronate to short-aristate. Perigynia ascending, pale brown, sometimes with purple-brown spots on apical 1/2, veinless, somewhat inflated, loosely enclosing achenes, narrowly ellipsoid to narrowly ovoid, 2.7–3.3(–3.6) × 1–1.8 mm, leathery, dull, base with stipe to 0.3 mm, apex acute, short-papillose; beak widely conic, 0.1–0.3 × 0.3–0.5 mm. Achenes entire to slightly constricted on margins, apex truncate to retuse, dull; style base straight, rarely bent. 2n = 78, 80–83.
