Herbs annual or biennial, hispid and appressed pubescent, hairs discoid at base. Stems erect or prostrate. Leaves alternate, ovate to oblanceolate. Cymes bracteate. Flowers pedicellate. Calyx 5-parted; lobes lanceolate, not enlarged or slightly enlarged in fruit. Corolla rotate, blue or white; tube short; throat appendages 5, scalelike; lobes 5, overlapping in bud, apex obtuse. Filaments extremely short; anthers 5, inserted in corolla tube, included; anthers ovate, obtuse. Ovary 4-parted, valves free, each containing 1 anatropous ovule. Style short, not surpassing valves; stigma capitate. Gynobase flat. Nutlets 4, with cupular emergence adaxially, rounded abaxially, tuberculate, with an oblong, elliptic, or orbicular ringlike aperture; margin of aperture thickened, prominent, entire or sometimes finely dentate; attachment scar basal. Seeds usually not curved.

About five species: Afghanistan, China, India, Indonesia (Java, naturalized), Japan, Kazakhstan, Korea, Kyrgyzstan, Pakistan, Russia, Tajikistan, Turkmenistan, Uzbekistan, Vietnam; all five in China.