Spectacular Flatsedge

Herbs, perennial, rhizomatous. Culms trigonous, (12–)30–80(–90) cm × 0.7–1.7 mm, glabrous or nearly so. Leaves flat to V-shaped, 20–45 cm × 2–4 mm, margins and keel minutely scabridulous. Inflorescences: spike 1, loosely ovoid to ovoid-ellipsoid, (1.5–)2.5–7 × (1–)1.5–3.5 cm; rays 1–4, 1–15 cm; rachis 1–2 cm; bracts 2–4, oblique or ascending, 1–15(–24) cm × 0.4–3.5 mm, keel, margins scabrid; rachilla ± deciduous, wingless. Spikelets (3–)8–40, linear, compressed-quadrangular, 8–18 × (2.4–)2.8–4 mm; floral scales deciduous, (2–)4–12, laterally light brown to reddish brown, medially green or light brown, laterally 2–3-ribbed, oblong-ovate, 1.6–2.6 × (1.5–)1.6–2.2(–2.4) mm, apex obtuse, sometimes mucronulate, medially glabrous. Flowers: anthers 0.4–0.6 mm; styles 0.3–0.6 mm; stigmas 0.6–1 mm. Achenes brownish, stipitate, ellipsoid, 1.6–2 × (0.7–)0.9–1 mm, stipe whitish, 0.1–0.2 mm, apex obtuse, slightly apiculate, surfaces papillose.

Ariz., Tex.; Mexico.

Fruiting summer.

Arroyos, riverbanks, clearings in montane forests; 100–1300m.

Cyperus buckleyi Britton ex J. M. Coulter; C. parryi Britton ex C. B. Clarke; C. scaberrimus Nees; C. spectabilis var. filiformis Boeckeler; C. spectabilis var. parryi (C. B. Clarke) Kükenthal; C. spectabilis var. scaberrimus (Nees) Boeckeler