Nov. Gram. Gen. 23 ( 1779); Gen. Gram.: 366 (1986).- Type-species: Rotboellia exaltata L.f. (= R. cochinchinensis).
Coelorachis Brongn., Voy. Monde 2: 64 , f. 14 (1829);
Thyrsia Stapf, FTA 9: 48 (1917);
Robynsiochloa Jacques-Félix, J. Agric. trop. 7: 406 (1960).
Description:
* Erect annuals. Leaves flat; ligule membranous or a fringed membrane.
* Inflorescence an axillary cylindrical raceme, solitary or in false panicles. Internodes clavate, fused partly or wholly to the pedicels. Sessile spikelet sunken in the internode.
* Sessile spikelet with truncate callus and central peg. Lower glume coriaceous, 2-keeled. Lower lemma hyaline; upper lemma entire, awnless. Pedicelled spikelet smaller than the sessile spikelet.
Genus with 4 species of the Old World tropics.