Tufted annuals or perennials, Leaf-blades linear, flat or folded, tapering, acute or obtuse; ligule membranous, less than 1 mm long, ciliolate; sheaths glabrous, keeled and often flabellate. Inflorescence terminal, solitary or a pair of dense, often ciliate or villous spikes. Spikelets 4-9(-12)-flowered, subsessile, alternate in 2 rows on a tough rhachis; glumes persistent, usually similar, membranous, glabrous, 1-nerved, ovate-lanceolate or the upper elliptic-oblong, acute, acuminate or with an awn-point; lowest 1-5(-7) florets fertile; lemma coriaceous, laterally compressed and keeled, usually ciliate on the lateral nerves and keel, entire or 2-toothed at the apex, with a subapical awn; callus acute, ciliate; palea ciliolate on the keels; upper (1)2.4(6) florets sterile and reduced to glabrous, rarely ciliate, clavate, awned or awnless lemmas. Grain ovate, obovate or oblong, pericarp always loose.