Annual (in ours) vinous or pilose small herbs. Stems erect, simple or branched, leafy, with simple eglandular hairs. Leaves not divided, subentire or crenulate, shortly petiolate. Flowers small, in axils of leaves, verticillate. Bracteoles absent. Calyx tubular-campanulate, 5-10-nerved, not bilabiate; teeth equal, as long as tube, conspicuously spinulose; tube bearded at throat. Corolla bilabiate, yellow; tube included within calyx; upper lip straight, flat, emarginate; lower lip 3-lobed. Stamens 4, didynamous, included in the tube of the corolla; thecae bilocular. Style included in corolla tube. Nutlets ovate, scarcely trigonous, apically rounded.