Description from Flora of China
Herbs perennial or biennial, perhaps sometimes annual. Cymes terminal on main stem and sometimes on leafy branches, not clearly scorpioid, forming ± glomerate clusters wider than long, becoming ± corymbose or loosely racemose in fruit, bracteate. Calyx parted to middle or slightly below; lobes 5, narrowly triangular or cuneate. Corolla blue, purplish, yellow, or white, ovoid-ellipsoid or obovoid, contracted at both ends, abruptly expanding from a short tube into a relatively large inflated throat, with inflated ribs below lobes and deep furrows between them; throat unappendaged; lobes loosely recurved above middle; nectary ringlike, ± minutely villous. Anthers coherent at base, affixed below middle; filaments affixed at base of throat. Style included or slightly exserted. Gynobase broadly pyramidal. Nutlets slightly incurved, ± ovoid, ca. as long as wide, adaxially with a coarse prominent keel; attachment scar basal.
About nine species: Bhutan, India, Nepal, Thailand; five species in China.