三头薹草 san tou tai cao

Rhizome oblique. Culms tufted, 18-40 × ca. 0.1 cm, slender, trigonous, scabrid at upper part. Leaves longer or shorter than culms, flat, 4-8 mm wide, margins and veins scabrid; persistent sheaths brown, fibriform. Involucral bracts leafy, without sheaths, lowest one longer than inflorescence, others very short, setaceous. Panicle spicate, 1-4-branched; inflorescence branches subsessile, fewer spiked, sometimes with sterile spike at lower part. Spikes bisexual, androgynous, dense, ovate-globose, 5-8 × 4-7 mm, subsessile; male part of spike not prominent, usually not exserted from female part, 3-5-flowered; female part densely fewer flowered; male glumes yellowish white, lanceolate, 4.5-5 mm, membranous, upper part hairy, with 1 midrib, apex acuminate; female glumes yellowish white, lanceolate, 3-3.5 mm, densely hairy, with 1 midrib and several fine veins, apex acuminate, with short awns. Utricles yellowish white, slightly inflated, trigonous, 4.5-5 mm, membranous, densely hairy, with 2 lateral keels and several fine veins, subsessile, margins very narrowly winged, apex contracted into long beak, orifice minutely 2-toothed. Nutlets pale yellow at maturity, ovate, trigonous, ca. 3 mm; style base thickened and pyriform; stigmas 3.

Forests; 700-1100 m. S Yunnan (Xishuangbanna) [Cambodia, Indonesia, Laos, Myanmar, Thailand, Vietnam].