Description from Flora of China
Andropogon melanocarpus Elliott, Sketch Bot. S. Carolina 1: 146. 1816 ["1821"]; A. polystictus Steudel; Cymbopogon melanocarpus (Elliott) Sprengel; Heteropogon acuminatus Trinius; H. polystictus (Steudel) Hochstetter; H. roylei Nees ex Steudel.
Annual. Culms robust, erect, usually solitary, 0.5–2 cm tall, supported by stilt roots. Leaf sheaths spotted with rows of glands along veins, long soft hairs at mouth; leaf blades flat, 10–40 × 0.5–1 cm, pilose, apex acuminate; ligule lacerate. Inflorescence of racemes gathered into a copious spathate panicle; spatheoles linear-lanceolate, glandular; peduncle ca. 1/2 spatheole length, scarcely exserted. Racemes 2–4 cm (excluding awns), 3–8-awned, 1–3 pairs of green homogamous spikelets below the awned fertile pairs. Sessile spikelet 6–8 mm, blackish brown; callus 3–4.5 mm, sharply pungent, brown bearded; lower glume narrowly oblong, densely pilose with soft brown hairs; awn 6–9 cm, stout, column blackish when mature, hirtellous. Pedicelled spikelet 15–25 mm, lower glume light green, oblong-lanceolate, laterally asymmetrically winged, glabrous, pitted with glands and transversely pucked along midvein, lanceolate-caudate. Fl. and fr. Jun–Nov.
This species is immediately recognizable by the large, caudate pedicelled spikelets with a conspicuous, median, glandular band.
Mountain slopes; 1000–1500 m. Yunnan [India; Africa, tropical and subtropical America, SW Asia].