Description from Flora of China
Herbs perennial. Leaves petiolate, dentate. Verticillasters 4-10-flowered, in terminal racemes; bracts ovate. Pedicel slender. Calyx broadly funnelform, 2-lipped, very open in flower; upper lip 3-lobed, middle lobe circular, decurrent into tube at margin, lateral lobes much smaller; lower lip trapeziform, emarginate. Corolla tube narrow, glabrous inside, base with long slender spur, limb 2-lipped; upper lip reflexed, subequally 4-lobed; lower lip slightly longer, navicular, slightly concave. Stamens 4, didynamous; posterior 2 hairy at base, inserted at base of corolla tube, somewhat shorter than corolla limb; anterior 2 glabrous, inserted at throat, nearly as long as limb; filaments free; anthers 1-locellate. Style as long as posterior stamens, apex subequally 2-cleft. Nutlets subglobose, glabrous, minutely pitted.
About eight species: Asia, Australia; one species in China.