21. Cymbopogon microstachys (J. D. Hooker) Soenarko, Reinwardtia. 9: 364. 1977.
细穗香茅 xi sui xiang mao
Andropogon nardus Linnaeus var. microstachys J. D. Hooker, Fl. Brit. India 7: 207. 1896 ["1897"]; Cymbopogon flexuosus (Nees ex Steudel) Will. Watson var. microstachys (J. D. Hooker) Bor.
Perennial from a stout rootstock. Culms fairly slender to robust, 1.5–2 m tall, up to 1 cm in diam., nodes glabrous. Leaf sheaths glabrous, shortly auriculate; leaf blades linear, glaucous, 40–75 × 1–1.2 cm, glabrous, scabrid, base narrowed nearly to midrib on lower blades, apex finely acuminate; ligule 5–6 mm. Spathate compound panicle narrow or somewhat spreading, decompound, yellowish green or tinged purplish, up to 60 cm or more, branches lax, raceme pairs not densely clustered; spatheoles narrowly elliptic, 1–1.5 cm; racemes 1–1.3 cm; rachis internodes and pedicels pilose on margins; pedicel of homogamous pair not swollen. Sessile spikelet narrowly lanceolate-oblong, 3.5–4 × ca. 0.8 mm; lower glume flat or shallowly concave below middle, frequently slightly transversely wrinkled, sharply 2-keeled throughout, keels scarcely winged, wings not more than 0.1 mm wide, obscurely 1–3-veined between keels or veinless; upper lemma awned; awn 0.6–0.8 cm. Pedicelled spikelet 3–4 mm. Fl. and fr. Aug–Oct. 2n = 30.
Rocky hill slopes, forest margins; ca. 1200 m. S Yunnan [India, Myanmar, Thailand].
This species is part of the complex centered around Cymbopogon khasianus and is distinguished mainly by its small racemes and spikelet parts.