Rhizomatous, caespitose or scrambling perennial, branching at nodes. Branching extravaginal. Auricles 0-1-2, fringed with long cushion-based hairs. Spikelets laterally compressed, solitary, pedicelled, in open laxly branched panicles or slender racemes, falling entire from above persistent, unequal, 1-3-nerved, glumes; 3-flowered, 2 lower reduced to unequal, awned, scabrid or glabrous, indurated, 3-7-nerved, Ø lemmas, the lowermost always with a bearded callus. ☿ floret < Ø lemma, chasmogamous or cleistogamous; lemma prickle-toothed at apex otherwise glabrous, keeled, 3-5-nerved, shortly awned, mucronate or awnless. Palea membranous, 1-nerved, ≤ lemma, often enfolded by upper Ø lemma. Lodicules 2, membranous, entire or lobed, strongly nerved, sometimes hairy on margins, 0 in cleistogamous flowers. Stamens 1-4; anthers tailed, much reduced in cleistogamous flowers. Styles free; stigmata plumose, naked below or branches to base. Caryopsis free, linear, compressed; embryo ± ⅙ of caryopsis; hilum linear = caryopsis. Axillary, single-spikeleted cleistogenes occur in and . Fig. 2.