Culms obtusely angled, 110 cm × 5 mm, glabrous. Leaves: sheaths with red-brown spots, to 60 cm, backs green or red tinged, fronts membranous, apex concave to V-shaped; blades 120 cm × 7–18 mm, leathery, margins revolute, prominently keeled, antrorsely scabrous on margins and keel, glaucous when young, glossy adaxially, surface papillose abaxially. Inflorescences with 5–20 spikes, 25–80 cm; pistillate spikes 4–10, 3–13 cm × 10–12 mm. Scales red-brown with broad yellow-brown midrib, oblong, 3.5 × 1 mm, margins hyaline, apex acuminate or retuse, awn 0.5–3 mm, ciliate. Anthers 3–4 mm. Perigynia pale brown, with uniformly distributed red-brown spots, somewhat flattened to strongly inflated distally, 3.5–4.8 × 1.5–2.5 mm, base cuneate, apex obtuse, somewhat glaucous; beak red-brown, flared, abaxially obliquely bidentately cut, 0.5 mm. Achenes dark brown, stipitate, ellipsoid, 2 × 1.2 mm.