Perennial with short rhizome. Stems tall, tufted, trigonous, triquetrous just below the inflorescence, smooth, up to 100(-150) by 1 cm. Leaves coriaceous, flat, the larger ones somewhat plicate with the midrib prominent beneath and 2 lateral nerves marked above, scabrous on the margins in the upper part, dark green or glaucous above, whitish striate beneath, 6-15 mm wide. Inflorescence compound or decompound, usually large. Involucral bracts 4-6, the larger ones far overtopping the inflorescence, up to 75 cm. Primary rays 6-10, very unequal, obliquely patent, rigid, smooth, up to 30 cm, the larger ones bearing 5-7 up to 6 cm long secondary rays. Spikes narrow, more or less penicillate, 3-4 cm by 5-10 mm, loose, with glabrous rachis and 15-25 spikelets. Spikelets spicately arranged, suberect, oblong-linear, distinctly compressed, 8-14-flowered, 6-14 by c. 2 mm; rachilla slightly flexuous, winged, persistent; internodes c. ¾ mm; wings lanceolate, whitish hyaline, persistent, c. ¼ mm wide. Glumes membranous, obliquely erect to patulous, keeled, oblong, obtuse, broadly whitish hyaline-margined in the upper half, soon incised at the tip and mucronulate) by the excurrent midrib, 7-nerved, ⅓ imbricate, 2-2½ by c. 1 mm; keel greyish green, sides pale fuscous. Stamens 3; anthers oblong-linear, ½-1 mm, with distinctly produced, smooth appendage of the connective. Stigmas 3. Nut triquetrous, oblong to, oblong-ovoid, apiculate, brown, c. 1½ by ½ mm.
Swamps, wet rice-fields, moist places in forests, margins of pools, river-banks, at low altitudes (up to 800 m, in New Guinea, Western Highlands, collected at c. 1500 m).
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