Cyperus durus Kunth

Perennial herb, up to 0.53 m high, long-rhizomatous. Leaf blades 1.3-1.9 mm wide, semi-terete with ± pungent apex. Culm scapose, obscurely 3-angled, 1.0-2.2 mm in diam. Inflorescence pseudolateral, an anthela of to 4 spikes, contracted, spikes ovoid, 10-26 x 9-22 mm. Subtending bracts 2-5, the largest erect, in line with culm, otherwise leaf-like. Spikelets densely packed, compressed, ovate-lanceolate, 5.2-9.3 x 1.6-2.9 mm, 4-7-flowered. Glumes 3.4-4.3 mm long, imbricate, spaced ± 1 mm apart, concave, ovate when flattened, keel non-excurrent or excurrent into minute point. Flowering time Sept.-Nov. Nutlet narrowly elliptical, 1.7-2.1 x 0.6-0.7 mm, ± 3-angled, brown, surface puncticulate or minutely reticulate.