Description from Flora of China
Herbs, perennial, terrestrial, rhizomatous. Stems simple. Leaves few, along stem, opposite, unequal to subequal in a pair; leaf blade puberulent, base cuneate to subcordate. Inflorescences lax or dense, 3-12-flowered cymes axillary near stem apex; bracts 2, forming a globose involucre. Calyx actinomorphic, 5-lobed to 5-sect from base; segments equal. Corolla white to yellow, zygomorphic, inside glabrous; tube funnelform, somewhat gibbous abaxially, longer than limb, 1-1.5 cm in diam.; limb 2-lipped; adaxial lip 2-lobed; inconspicuous, much shorter than abaxial lip; abaxial lip 3-lobed, lobes subequal, apex rounded to truncate or acute. Stamens 2, adnate to abaxial side of corolla tube near middle, included; anthers basifixed, coherent at apex, thecae parallel, not confluent at apex, dehiscing longitudinally; connective not projecting; staminodes 2 or 3, adnate to adaxial side of corolla tube. Disc ringlike. Ovary linear, 1-loculed; placenta 1, parietal, projecting into locule, undivided. Stigma 1, terminal, depressed-globose or capitate, undivided. Capsule straight in relation to pedicel, linear, much longer than calyx, dehiscing loculicidally to base; valves 2, straight, not twisted. Seeds unappendaged.
* Two species: endemic to China.