Isachne clarkei Hook. fil.

This is not a common grass, but is found at low altitudes in southern Taiwan.

The specimens from India (Sikkim) cited by Hooker in the protologue are Isachne sikkimensis.

Culm weak, about 10 cm high, branching and rooting at the lower nodes. Blade linear-lanceolate, 2.5-3 cm long by 5 mm wide, glabrous or scabrous, sometimes pubescent; ligule a ring of long rigid hairs. Inflorescence an oval panicle. Spikelets subglobose, purplish in color, about 1.5 mm long; glumes ovate, obtuse, slightly gibbose, herbaceous, 7-nerved, more or less hispid, nearly equaling the spikelet. Lower floret 1-1.5 mm long, subglobose, obtuse, convex, coriaceous, pale in color, densely pubescent. Upper floret 1.5-2 mm long, broadly ovate, acute.

Delicate annual. Culms very slender, laxly ascending, base often decumbent, rooting at lower nodes but not stoloniferous, 12–30 cm tall, panicles terminating main stem and also short lateral branches. Leaf sheaths pilose, sometimes sparsely, outer margin ciliate; leaf blades linear-lanceolate, thin, 2–6 × 0.3–0.7 cm, glabrous or pilose, margins firm, apex acute; ligule 1–1.5 mm. Panicle open, ovate to pyramidal in outline, 1.5–8 cm, many-spiculate when well developed; branches and pedicels regularly spaced, divaricate at maturity, capillary, smooth; pedicels longer than spikelets, often with a gland halfway along their length. Spikelets subglobose, 1–1.5 mm, green or purplish; florets similar; glumes subequal to spikelet, ovate, lower (3–)5-veined, upper 7-veined, hispidulous to setose above middle, margins broad, incurving at apex; lemmas whitish, strongly convex, leathery, densely pubescent. Fl. and fr. Jul–Nov.

Distributed in Malaysia, Vietnam, Southern China, the Philippines and Java.

Fujian, Taiwan, Xizang, Yunnan [NE India, Indonesia, Malaysia, Myanmar, Philippines, Vietnam].

Damp mountain grasslands, streams, valleys; 1300–2400 m.

Isachne beneckei var. depauperata Ohwi, l. c. 11: 55. 1942.

Isachne beneckei Hackel; I. tenuis Keng ex P. C. Keng.