Plants densely to loosely cespitose. Culms 23-88 cm × 0.5-1.6 mm, smooth. Leaves: ligules 1-3.5 mm, 1-3 times as long as wide; blades 1.1-4.4 mm wide, widest blade 1.3-4.4 mm wide. Inflorescences (12-)21-63(-71) mm; proximal internode 3.3-16(-23) mm; proximal bracts 5-24(-28) mm, awn 1.3-19 mm; spikes 3-8, usually gynecandrous, sometimes also pistillate, staminate or with pistillate and staminate flowers scattered throughout; proximal spikes with 0-2 staminate and 9-19 pistillate flowers, 10-17(-20) × 1.8-5 mm; terminal spikes usually with 0-3 staminate and 8-18 pistillate flowers, 9-20(-25) × 1.5-5 mm. Pistillate scales with pale to red-brown margins, 2.8-4.1 × 1.1-1.6 mm, apex acuminate or with awn to 0.6 mm. Staminate scales with pale to red-brown margins, 2.8-3.9 × 1.4-1.6 mm, apex acute to acuminate. Anthers 1.7-2.9 mm. Perigynia erect, green to pale brown, (3-)4-8-veined abaxially, prominently to weakly 3-6-veined adaxially, narrowly lanceolate, (3.3-)4.1-6.7 × 0.8-1.3 mm, (3.5-)4-6.1(-6.6) times as long as wide, apex abruptly contracted or gradually tapering; beak 1.2-2.2(-2.8) mm, 0.28-0.51 times as long as perigynia, margins serrulate, apex entire or bidentulate, teeth to 0.2 mm, 0-0.05 times as long as perigynia. Stigmas 2-3.4 mm. Achenes 1.7-2.2 × 0.7-1.1 mm, 1.9-2.9 times as long as wide.