Rhizome neck 11–65 cm, internodes hollow. Culms to 4 m, 1–2 cm in diam.; internodes terete, 21–34 cm, white powdery in ring below nodes, slightly setulose initially; wall 2–3 mm; longitudinal ribs prominent; nodes with weakly prominent supra-nodal ridge; sheath scar level, glabrous. Branches 3–7. Culm sheath gradually deciduous, rectangular, conspicuously longitudinally ribbed, leathery, abaxially glabrous and waxy, margins dark gray ciliolate; auricles and oral setae absent; ligule truncate, ca. 0.5 mm, glabrous; blade linear-triangular, adaxially yellow-brown hairy proximally, revolute. Leaves 2 or 3 per ultimate branch; sheath apically puberulous with glabrous margins; auricles absent; oral setae gray, 3–4 mm; ligule truncate, glabrous; blade lanceolate, 3.3–6 × 0.5–0.8 cm, basally broadly cuneate or rounded, abaxially gray pubescent, secondary veins 2-paired, transverse veins distinct, margins scabrous. Inflorescence unknown. New shoots May–Jun.