Plants loosely cespitose; rhizomes slender. Culms 13–40 cm, smooth, sparsely pilose. Leaf blades M-shaped in cross section when young, 2–4.5 mm wide, at least proximal pilose. Inflorescences: proximal bracts sheathless or sheath not more than 2 mm; lateral spikes 6–27 × 4–9 mm, all in distal 1/2 of stem; terminal spike 8–20 × 1–2.5 mm. Pistillate scales 3-veined, ovate, 2.3–3 × 1.3–2.2 mm, shorter than perigynia, apex acute, sometimes with awn to 0.7 mm. Staminate scales 3-veined, 3.2–5 × 1.2–2 mm. Perigynia 20–30-veined, narrowly ovoid, 4.5–6 × 1.4–2 mm, spongy at base, subglabrous to puberulent proximally, pilose distally, at least some hairs 0.3–0.4 mm; beak obscure, 0.3–0.5 mm. Achenes: stipe to 1 mm; bodies 2.5 × 1.3–1.7 mm, filling only distal part of perigynia.