闪穗早熟禾 shan sui zao shu he

Perennials, glaucous throughout, loosely tufted, subrhizomatous; shoots extra- and intravaginal. Culms erect or ascending, 30–60 cm, ca. 1 mm in diam., nodes 2, none or 1 exserted, smooth or sparsely scabrid below, uppermost less than 1/3 way up. Leaf sheaths glabrous or lowermost scabrid to covered with minute hairs, 8–11 cm, 1–1.5 × as long as blade, uppermost closed for 2/5–1/2 of length; blades flat or folded with margins inrolled, thickly papery, 4–12 cm × (1–)2–3.1 mm, abaxially smooth, adaxially sparsely scabrid, margins scabrid, apex slender prow-tipped, of tillers short; ligule milky-membranous, 2.7–6 mm, abaxially smooth, lower ones scabrid, of tillers 0.7–1 mm, abaxially scabrid, collar margins rounded, glabrous or sparsely ciliate. Panicle open, well exserted, 11–16 × 6–10 cm, longest internodes 3–3.5 cm; branches spreading, flexuous, 2 per node, proximally smooth, distally sparsely scabrid, longest 4–7 cm with 4–8 spikelets in distal 1/2; flowers female or perfect. Spikelets ovate to oblong, glaucous, 6.2–6.7 mm, florets 2 or 3; vivipary absent; rachilla internodes up to 1 mm, scabrid or pilulose; glumes unequal to subequal, lanceolate or oblong, keel distally scabrid, surfaces smooth or faintly punctate-papillate, lower glume 3.1–4.5 mm, 1- or 3-veined, upper glume 4.1–5 mm, 3-veined; lemmas oblong, 6–6.5 mm, apex obtuse, keel crisply pilulose to short villous for 2/5 of length, marginal veins to 1/3, intermediate veins moderately raised, area between veins proximally densely scabrid to crisply pilulose, distally smooth or sparsely scabrid; callus glabrous or sparsely webbed; palea scabrid or pilulose between keels, keels scabrid. Anthers 2.5–3 mm, or vestigial. Fl. and fr. Jun–Aug.

Alpine sunny slopes, grassy places in river valleys; 4400–4700 m. Xizang [India (Sikkim), Nepal].

The lemmas have a shortly pubescent abaxial surface and a broad, membranous margin, and the callus is glabrous. The species is similar to Poa polyneuron, but differs in having long leaf blades and ligules, larger spikelets up to 7 mm, long glumes and lemmas, and the lemma only 5-veined.