Herbs annual. Leaves alternate, sessile or short petiolate. Cymes bracteate. Calyx 5-parted to base, slightly enlarged in fruit. Corolla campanulate; throat appendages 5, broadly linear to subulate; limb 5-parted; lobes broadly ovate. Stamens inserted at middle of corolla tube, included; filaments short; anthers ovoid to oblong. Ovary 4-parted. Style included; stigma terete. Gynobase conical. Nutlets ovoid, slightly dorsiventrally compressed, densely tuberculate; disc margin 2-layered, inside layer membranous and entire, outside layer leathery and pectinate-dentate; attachment scar at apex adaxially. Seeds ovoid, dorsiventrally compressed.

About three species: China, Vietnam; two species in China.