12. Achnatherum psilantherum Keng ex Tzvelev, Rast. Tsentr. Azii. 4: 41. 1968.
光药芨芨草 guang yao ji ji cao
Perennial, densely tufted. Culms erect, 40–100 cm tall, 1–1.5 mm in diam., 2–3-noded. Leaf sheaths smooth, shorter than internodes; leaf blades filiform, to 12 cm, to 0.5 mm wide, surfaces smooth or scaberulous; ligule truncate, 0.1–0.5 mm, often toothed. Panicle loosely contracted, narrowly oblong in outline, 5–15 cm; branches 2 to several per node, suberect or slightly spreading, delicate, up to 2.5 cm. Spikelets 6–7 mm, purple with pale hyaline apices; glumes subequal or lower glume slightly shorter, lanceolate, 3-veined, apex acuminate to a fine point; callus subacute, ca. 0.3 mm; lemma 3.8–4.5 mm, densely pubescent, apex subentire; awn caducous, 1.5–1.8 cm, 1-geniculate, scabrid, column weakly twisted; palea as long as lemma. Anthers 2–2.5 mm, glabrous at apex. Fl. and fr. Jun–Sep.
* Grassy and rocky mountainsides, river banks, floodlands; 2000–4100 m. Gansu, Qinghai, Sichuan.