匍匐柳叶箬 pu fu liu ye ruo

Isachne kunthiana (Wight & Arnott ex Steudel) Miquel subsp. nudiglumis (Hackel) T. Koyama; I. kunthiana var. nudi-glumis (Hackel) T. Koyama; I. myosotis Nees var. nudiglumis Hackel.

Slender trailing herb, annual or short-lived perennial. Culms stoloniferous with 1 or 2 wiry roots from lower nodes, flowering branches up to 25 cm tall, nodes pubescent. Leaf sheaths glabrous or hispid, outer margin ciliate becoming setose near ligule; leaf blades lanceolate, 5–7 × 1–1.8 cm, abaxial surface glabrous or papillose-hispid, adaxial surface glabrous or thinly pilose, base obtuse to rounded, apex acuminate; ligule 1–2 mm. Panicle elliptic to ovate in outline, 3–5.5 cm, eglandular; branches ascending to spreading, branches and pedicels stout, smooth, lateral pedicels shorter than spikelets. Spikelets broadly elliptic, 2.1–2.4 mm, green; florets similar; glumes equal to spikelet or upper slightly shorter, lower glume narrower, 7–9-veined, upper 9–11-veined, densely scabrid-hispidulous, spicules longer toward apex; lemmas pale, ovate to subrotund, weakly convex, leathery, smooth, pubescent on the inrolled margins toward apex; palea of upper floret puberulous. Fl. and fr. Oct–Dec.

Moist places in forests. Fujian, Guangdong, Guangxi, Hainan, Taiwan [Japan (S Ryukyu Islands)].

This species is very close to Isachne schmidtii Hackel, from Indonesia and peninsular Malaysia, which is somewhat smaller, with shorter leaf blades, a more contracted panicle, and especially differs in its glumes extending beyond the florets. Isachne schmidtii has often been confused in the literature with I. kunthiana (Wight & Arnott ex Steudel) Miquel, from India and Sri Lanka, which also has glumes longer than the florets, but differs by its underground rhizomes and glabrous or setose glumes.