Low growing annuals; culms prostrate or geniculately ascending. Leaf-blades usually short. Inflorescence a hemispherical to ovoid head, or a cylindrical spiciform panicle, embraced below by 1-2 inflated bract-like leaf-sheaths bearing a reduced blade, or sometimes exserted. Spikelets strongly laterally compressed, disarticulating below the floret, sometimes tardily so or rarely falling entire, awned or awnless; glumes subequal, shorter than the lemma; lemma 1-nerved; palea 1-2-nerved. Fruit rounded at the tip, not beaked.