Description from Flora of China
Perennials. Rhizomes short, thick, woody, creeping. Culms tufted, 30-50 cm tall, 1.4-2 mm wide, 3-angled, glabrous. Leaves basal and cauline. Basal leaves sheathlike, bladeless. Cauline leaves with sheath 3-angled, closed, pilose; contraligule depressed rounded or depressed deltoid, ciliate; leaf blade narrowly linear, 1.5-2 mm wide, margins finely serrate, apex attenuate into a caudate tip. Involucral bracts leaflike, basal one to 10 cm, sheathing. Inflorescences paniculate, well-developed ones more than 30 cm, with 1-3 lateral branches or without branch at basal part; basal part often reduced to spikelike, 3.5-7 cm. Spikelets 1-3 in a cluster, 3-4.5 mm, with 4 or 5 glumes, with 1 or 2 male flowers and 1 female flower below male ones. Glumes ovate-lanceolate, keeled, both sides of midvein membranous with short brown lines, apex mucronate. Disk not well developed. Nutlet white, broadly obovoid to subellipsoid, ca. 2.5 mm, 3-sided or not, smooth or transversely rugose or irregularly ± reticulate with wavy ridges, shiny, base narrow and triangular. Fl. and fr. Jun-Oct.
Thickets in forests, woods; 100-1000 m. Guangdong, Hainan, Taiwan, SE Yunnan [India, Indonesia, Malaysia, Myanmar, Papua New Guinea, Philippines, Sri Lanka, Thailand, Vietnam; tropical Africa, America, and Australia, Indian Ocean islands, North and South America, Pacific islands].