Annual to perennial herbs. Stems several, ascending to erect, with eglandular simple hairs, leafy. Leaves elliptic to ovate-spathulate, petiolate, subentire to crenate-serrate, broadly cuneate at base, apically rounded or obtuse. Verticillasters several in axils of upper leaves, congested or distant, forming terminal heads or spikes. Bracts present, deciduous or not, small. Calyx regular, campanulate, 10-nerved; teeth 5 triangular-lanceolate, equal; tube ± as long as teeth, ± glabrous at throat. Corolla pink, blue to lilac (in ours), bilabiate, usually persisting after withering for some time; upper lip subabsent or very short; lower lip with 2 lateral lobes and a much larger emarginate central lobe; tube slender, annulate or not within, exserted from calyx. Stamens 4, didynamous, anterior pair longer, included within corolla or clearly exserted from it; thecae glabrous or pilose, becoming unilocular. Style clearly 2-lobed, not gynobasic, inserted above base of ovary lobes. Nutlets 4, transversely rugose, with a very large lateral attachment scar, not mucilaginous on wetting, obovoid, neither trigonous nor truncate.