雀稗尾稃草 que bai wei fu cao

Brachiaria ambigua (Trinius) A. Camus; B. paspaloides (J. Presl) C. E. Hubbard; Panicum ambiguum Trinius; Urochloa ambigua (Trinius) Pilger.

Annual. Culms slender, spreading, branching and rooting at lower nodes, 20–60 cm or more tall, nodes pubescent. Leaf sheaths glabrous or loosely pilose; leaf blades linear, 5–20 × 0.3–0.8 cm, thinly pilose on both surfaces with tubercle-based hairs, apex acuminate; ligule ca. 1 mm. Inflorescence axis 1.5–4 cm; racemes 2–4, 2–5 cm, rather stiffly ascending; rachis narrow, triquetrous, scabrous; spikelets usually paired, loosely overlapping. Spikelets lanceolate, 3.5–4 mm, glabrous, sharply acute; lower glume lanceolate, 2/3–3/4 spikelet length, 5–7-veined, acute and apiculate; upper glume 5–7-veined, sharply acute; lower lemma obscurely 5-veined, palea very small; upper lemma elliptic-oblong, only slightly shorter than spikelet, finely rugulose, mucro 0.4–0.5 mm. Fl. and fr. May–Oct. 2n = 36.

Mountain slopes, forests. Hainan, Yunnan [India, Japan (Ryukyu Islands), Malaysia, Philippines, Sri Lanka].

This is the only species of Urochloa in China with a long lower glume.