Cyperus castaneus Willd.

Annuals. Roots fibrous. Culms tufted, 3-15 cm tall, 3-angled, smooth, base with few leaves but often withered by flowering time. Leaves shorter than culm; leaf blade 0.4-1 mm wide, folded. Involucral bracts 2-5, linear, longer than inflorescence. Inflorescence a simple anthela; rays 1-4, to 3 cm. Spikelets 5-30, digitately or stellately arranged at apex of ray, linear, 5-20 × 1-1.8 mm, 8-26-flowered; rachilla wingless. Glumes purplish red, ± laxly imbricate, oblong to oblong-lanceolate, 1.2-1.7 mm, 3-veined, apex subobtuse to emarginate and with a recurved 0.2-0.5 mm awn. Stamens 2 or 3; anthers ellipsoid, 0.1(-0.2) mm. Nutlets brown, narrowly oblong, 0.7-0.9 mm, 3-sided, surface minutely punctate. Fl. and fr. Jun-Sep. 2n = 40.

In open sandy localities, up to 300 m.