Tragus mongolorum Ohwi

This species has been widely known under the name Tragus biflorus Schultes, which is illegitimate because it was nomenclaturally superfluous when published. Panigrahi replaced T. biflorus with T. roxburghii, but overlooked Ohwi's earlier name, T. mongolorum, which was validly published, is legitimate, and is therefore the correct name for the species.

The spiny burrs cling easily to skin and clothing.

Annual, mat-forming. Culms tufted, ascending from prostrate base, rooting at nodes, up to 25 cm tall. Leaf sheaths usually shorter than internodes, uppermost longer, inflated, often clasping base of inflorescence; leaf blades broadly linear, tough, flat, glaucous, 3–8 cm, 2–4 mm wide, margins thick, pectinate-spinose, apex acute. Inflorescence 3–6 × ca. 0.8 cm; racemes of 2 subequal contiguous spikelets, rachis internode ca. 0.2 mm; rachis extension absent or up to 1.5 mm beyond upper spikelet, sometimes bearing rudimentary 3rd spikelet, this often reduced to a row of spines; basal peduncle 0.3–0.5 mm. Lower spikelet fertile, elliptic, 3.5–4 mm; lower glume very small, membranous; upper glume 5-ribbed, ribs bearing hooked, thick-based spines, apex acuminate-attenuate; lemma ovate-lanceolate, ca. 3 mm, puberulous, apex sharply acute. Upper spikelet similar to lower but slightly smaller, 3.2–3.7 mm, fertile. Fl. and fr. Jul–Sep.

Hill slopes, roadsides, a weed of cultivation. Gansu, Hebei, Nei Mongol, Ningxia, Qinghai, Shanxi, Sichuan, Xizang, Yunnan [India, Malaysia, Myanmar, Pakistan, Thailand; Indian Ocean Islands (Mascarenes)].

Tragus roxburghii Panigrahi.