Plants cespitose. Culms 10-40 cm, smooth. Leaves 3-4 mm wide. Inflorescences: proximal bracts shorter than, sometimes equaling or, occasionally, exceeding inflorescences; spikes overlapping, contiguous, forming a dense terminal cluster or, sometimes, proximal spikes separate and distinct, sessile, short-oblong, 7-10 × 5-7 mm; lateral 2-3 spikes pistillate; terminal spike gynecandrous. Pistillate scales dark brown or black to margins, lanceolate, shorter or longer than, and narrower than, perigynia, midvein same color as body, inconspicuous, apex usually acute, occasionally short-mucronate. Perigynia ascending, glossy reddish brown, often with yellowish or greenish brown margins, veinless, obovate or circular, 3.5-4.5 × 2.5-3 mm, apex abruptly beaked, smooth; beak 0.5-0.8 mm, deeply bidentate, smooth. Achenes filling proximal 1/2 or less of perigynia.

Fruiting Jul-Aug. Alpine slopes, ridge crests, rocky lakeshores; 2700-3700 m; Colo., Idaho, Mont., Nev., Oreg., Utah, Wyo.

Carex pelocarpa has often been treated within C. nova; it is distinguished on the basis of perigynia, pistillate scales, and ecology.