Densely caespitose perennial, the basal sheaths flabellate. Culms 30–90 cm. high, erect. Leaf-blades flat, 15–30 cm. long, 3–5 mm. wide. Inflorescence 9–11 cm. long, with a short central axis 1–5 cm. long; racemes 2–8, each 3–9 cm. long; internodes and pedicels clavate, usually pubescent. Sessile spikelet narrowly ovate, dark purple; callus without a peg; lower glume 4–5 mm. long, chartaceous with 2–5 prominent raised intercarinal nerves, these ± ciliate, the keels ciliate above and scarcely winged, subacute to emarginate at the tips; lower floret barren. Pedicelled spikelet resembling the sessile or smaller, without a callus.