18. Yushania exilis T. P. Yi, J. Bamboo Res. 5(1): 20. 1986.
沐川玉山竹 mu chuan yu shan zhu
Rhizome neck ca. 50 cm; internodes less than 8 mm in diam., solid. Culms 1.5–2.5 m, 5–8 mm in diam.; internodes initially purple spotted, terete, 25–28 cm, white powdery especially below nodes, glabrous, not ribbed; wall 1.5–2 mm; nodes with level or weakly prominent supra-nodal ridge; sheath scar prominent. Branches 1–8, pendent toward apex. Culm sheaths persistent, purple-brown, narrowly triangular, shorter than or equal to internodes, leathery, sparsely brown setulose, margins initially brown setulose, longitudinal ribs prominent; auricles absent; oral setae 4–6, erect, 5–12 mm; ligule purple-brown, truncate, 1–2 mm, glabrous; blade linear-lanceolate, glabrous, margins serrulate, rolled, revolute. Leaves 4–6 per ultimate branch; sheath glabrous; auricles absent; oral setae 1–3, erect, gray-brown or brown, 2–5 mm; ligule arcuate, ca. 1 mm, glabrous; blade linear-lanceolate, 2.3–9.5 × (0.35–)0.5–0.8 cm, glabrous, secondary veins 3-paired, transverse veins visible, base cuneate, margins serrulate. Inflorescence unknown. New shoots May.
* 1200–1500 m. S Sichuan.