Description from Flora of China
Herbs, perennial. Rhizomes short, creeping. Culms terete. Leaves cauline; leaf blade V-shaped in cross section, margin scabrous. Involucral bracts leaflike, sheathing. Inflorescence an elongated compound anthela. Spikelets ovoid. Glumes ± spirally arranged, basal 4-6 empty, apical 2 fertile, apicalmost flower bearing a nutlet. Perianth bristles absent. Stamens 2. Stigmas 3; style base not distinct, thickened, persistent. Nutlet ovoid, subterete.
About four species: tropical and warm temperate regions of Asia, Australia, Europe, North and South America, and Pacific islands; one species in China.
(Authors: Liang Songyun (梁松筠 Liang Song-jun); Jeremy J. Bruhl, Karen L. Wilson)