Herb, perennial, dioecious, caespitose, forming large tangled masses to 1.5 m high when growing among shrubs, or much lower with spreading culms in open sites; cluster roots present. Cataphylls similar to sheaths but shorter. Culms arising from a narrow base, erect or spreading, much-branched and flexuose, minutely dotted with tanniniferous cells, dull-grey to yellowish green, striate, 0.3–1.0 (–1.5) m long; 0.5–1.5 mm diam. Sheaths 0.5–2.0 cm long, green to light-brown, with a narrow membranous margin; ligule a narrow, glabrous, membranous flap of tissue; lamina slender, compressed to terete, to 2–3 mm long, occasionally longer. Spikelets sessile or shortly pedicellate; spathes lanceolate, 2.5–4.5 mm long, herbaceous, green to light brown, reddish when young. Male spikelets narrow-ovoid, 3–4 mm long. Glumes 4–10 (–24), mostly fertile, mucronate, green to golden-brown with a reddish apex, glabrous, 1.7–2.5 mm long; with a short, blunt mucro c. 0.5–1.4 mm long or with a long filiform, herbaceous awn. Female spikelets: axis often elongated so that the glumes do not overlap; glumes mostly subtending a flower or abortive flower, narrow-ovate, acute to subulate, herbaceous, green or pale brown, glabrous, 5.0–6.0 mm long, with a blunt herbaceous mucro to 2.2 mm long. Male flowers: outer tepals narrow-lanceolate, 1.8–3.2 mm long; inner tepals ± lanceolate, c. 2.0–2.5 mm long; filaments 2.5–3.5 mm long; anthers exserted, 1.2–1.6 mm long. Female flowers: outer tepals c. 4 mm long, narrow-linear, hyaline; inner tepals narrow-oblong, hyaline, acute, 3–4 mm long; style 2-or 3-branched, very shortly united at base, c. 3 mm long. Capsule elliptic, compressed, 1.5–2.5 mm long, dark brown. Seeds ovoid, brown, 1 mm long. Culm anatomy: chlorenchyma of 2 or 3 layers of short peg cells interrupted by sclerenchyma girders and enlarged epidermal cells but without pillar cells or protective cells; cavity present.