8. Tripogon filiformis Nees ex Steudel, Syn. Pl. Glumac. 1: 301. 1854.
小草沙蚕 xiao cao sha can
Tripogon filiformis var. tenuispicus J. D. Hooker; T. nanus Keng ex P. C. Keng & L. Liu; T. unidentatus Nees ex Steudel.
Culms 8–40 cm tall. Basal leaf sheaths papery becoming slightly fibrous; leaf blades 3–15 × 0.1–0.15 cm, adaxial surface scabrid, sparsely pilose, abaxial surface glabrous. Racemes 3–20 cm, variable, straight or flexuose, spikelets loosely erect or diverging from the slender rachis, imbricate by 1/2–3/4 their length. Spikelets 5–9 mm, pale green or tinged gray or purple; florets 4–10, tightly to loosely imbricate; lower glume narrowly lanceolate, asymmetrical, broadened into a prominent lateral tooth on one side, 1.6–2.7 mm, subacute; upper glume narrowly lanceolate-oblong, 3–4.5 mm, apex acuminate or emarginate and mucronate; lemmas elliptic-lanceolate, 2–2.7 mm to sinus, 3-awned with 2 teeth between the awns, central awn 3–8 mm, flexuose, sometimes recurving, teeth variable, acute, acuminate or awnlike, lateral veins extended into 1–3 mm awns; palea keels winged, shortly ciliate. Anther 1, 0.7–1.3 mm. Fl. and fr. Jun–Oct.
Dry grassy slopes, often among rocks; 1200–4200 m. Fujian, Guizhou, Henan, Shaanxi, Sichuan, Xizang, Yunnan, Zhejiang [Bhutan, N India, N Myanmar, Nepal, Pakistan].
Tripogon filiformis is a Himalayan species distinguished by its slender habit with dense, feathery racemes of long-awned spikelets, lemmas with teeth between the awns, and a single anther. The racemes are variable in length and color, but are usually rather flexuose with the leaf blades extending up among them.