Annuals or perennials. Inflorescence a single raceme, bearing inclined or pectinate spikelets on a semi-terete (crescent-shaped in section) rhachis. Spikelets 1-flowered, (rarely with a second developed male floret), alternate in two rows, disarticulating above the glumes. Glumes subequal, 1-nerved, enclosing the florets; lower keeled, upper dorsally rounded. Lemma membranous, keeled, acute to 2-lobed at the apex, awnless but sometimes minutely mucronate.