150. Tragus Haller, Hist. Stirp. Helv. 2: 203. 1768.
锋芒草属 feng mang cao shu
Authors: Shou-liang Chen & Sylvia M. Phillips
Nazia Adanson, nom. rej.
Annuals or perennials. Leaf blades narrow, flat; ligule a line of hairs, sometimes from a membranous base. Inflorescence linear, cylindrical, spikelike, dense, axis bearing numerous very short racemes; racemes subsessile or shortly pedunculate, falling entire as spiny burrs; spikelets 2–5, contiguous or on a short rachis, sometimes the upper reduced. Spikelets elliptic to lanceolate, floret 1; lower glume a tiny scale or suppressed; upper glume as long as spikelet, rounded, prominently 5–7-veined, veins forming ribs armed with conspicuous, stout, hooked spines, thin between ribs, apex acute to acuminate; lemma ovate, almost as long as glume, flattened, membranous, 3-veined, pubescent around midvein, apex entire; palea slightly shorter than lemma. Caryopsis ellipsoid to oblong, slightly dorsally compressed.
Seven species: tropical and warm-temperate regions of the Old World; introduced in America; two species in China.
Both species occurring in China have been confused with the Mediterranean, African, and SW Asian Tragus racemosus (Linnaeus) Allioni, which differs in having 7 veins (vs. 5) in the upper glume.