Tetrarrhena acuminata

Rhizomatous perennial, stems decumbent or weakly ascending, to 1 m long. Leaves distichous, glabrous or minutely scabrous; blade flat, 2–7 cm long, 2–5 mm broad; ligule membranous, irregularly toothed, 0.8–2 mm long. Inflorescence a distichous, spike-like raceme 1.5–5 cm long. Spikelets subsessile, usually 4–12 per raceme, 7.0–13.0 mm long; glumes 0.8–3.0 mm long, the lower slightly shorter than upper, both smooth and glabrous; lower sterile lemma shorter than upper, acute or obtuse; upper sterile lemma acute to acuminate and sometimes shortly mucronate, both keeled, and 5–7-nerved, the nerves prominently raised and scabrous; fertile lemma slightly shorter than upper sterile lemma, often minutely mucronate, scabrous along keel, obscurely 5–7-nerved; palea subequal to fertile lemma; anthers 4. Flowers Oct.–Mar.