Description from
Flora of China
Annuals. Culms trailing. Leaf blades lanceolate; ligule membranous. Inflorescence composed of several slender, loosely spiculate racemes spaced along a central axis, spikelets paired but the sessile spikelet often reduced. Spikelets laterally compressed, florets 2; glumes equaling the spikelet or slightly shorter, lower glume acute to awned, upper glume gibbous, armed at maturity with coarse, tubercle-based hooklike bristles, apex acute or rarely awned; lower lemma equaling the spikelet, papery to subcoriaceous but membranous on the margins and with a median hyaline patch at the base; upper lemma laterally compressed, obliquely ellipsoid, cartilaginous to coriaceous, margins flat or inrolled.
Six species: one species throughout the tropics (including China), five endemic to Madagascar, in forest shade.
(Authors: Chen Shouliang (陈守良); Sylvia M. Phillips)