Description from Flora of China
Andropogon diplandrus Hackel, Flora 68: 123. 1855; Cymbopogon eberhardtii A. Camus; Hyparrhenia eberhardtii (A. Camus) Hitchcock.
Perennial. Culms tufted, coarse, 1–2 m tall, sometimes glaucous. Leaf sheaths glabrous; leaf blades 30–60 × 0.3–0.6 cm, glabrous or hirsute at base, margins scabrid; ligule reddish brown, ca. 2 mm. Spathate panicle loose, narrow; spatheoles narrowly lanceolate, 3–5 cm, brownish red; peduncle scarcely exserted from spatheole, glabrous or shortly bearded. Racemes 4–8-awned per pair, reflexed at maturity; raceme bases subequal, flattened, short, broadly oblong, glabrous on outer face, upper 1.5–3 mm; usually 2 pairs of homogamous spikelets at base of both lower and upper raceme of pair; homogamous spikelets scabrid-pectinate on upper keels. Sessile spikelet 6–8 mm; callus 1–1.5 mm, sharply acute, white bearded; lower glume lanceolate, glabrous or pilose; awn 2.5–4.5 cm, column with white or brown 0.2–0.5 mm hairs. Pedicelled spikelet 6–7.5 mm, acute or tipped with a mucro up to 1.5 mm. Fl. and fr. Aug–Nov.
This species can be recognized by its short, flat raceme bases and the pectinately margined homogamous spikelets, which form an involucre at the base of the raceme pair.
Hill slopes, thickets; 100–200 m. Guangdong, Guangxi, Hainan, Yunnan [Indonesia, Thailand, Vietnam; tropical Africa].