Carex sect. Triquetrae
in N. L. Britton et al., N. Amer. Fl. 18: 215. 1935.
Plants densely cespitose, short-rhizomatous. Culms brown at base. Leaves: basal sheaths not or slightly fibrous; sheath fronts dotted purple, membranous; blades M-shaped in cross-section when young, adaxial surface with 2 lateral-veins more prominent th an midvein, papillose, glabrous. Inflorescences racemose, with 3–4 spikes; proximal bracts leaflike, sheath to 3.5 cm; lateral spikes pistillate or, sometimes, androgynous with few staminate flowers, pedunculate, prophyllate; terminal spikes staminate. Proximal pistillate scales hyaline, green, or brown, apex acute to cuspidate. Perigynia ascending, obscurely veined or distinctly 6-veined, with 2 strong marginal veins, subsessile to sessile, ovate or obovate, trigonous in cross-section, base rounded-tapering, apex abruptly contracted to beak, pilose; beak 0.2–0.4 mm, orifice emarginate. Stigmas 3. Achenes trigonous, almost as large as bodies of perigynia; styles deciduous.
sw United States, nw Mexico