Rootstock of vertical, annual to biennial tubers. Stem twining to left, often pubescent. Bulblets absent. Leaves alternate, simple; leaf blade reniform to ovate, papery, margin entire. Male inflorescence a spikelike thyrse. Flowers in cymules, pedicellate; perianth campanulate, cupular, or saucer-shaped, lobes connate at base; stamens 6, inserted at base of perianth lobes or in throat of tube, anthers dorsifixed, introrse. Female inflorescences solitary or 2 or more together. Capsule usually reflexed at maturity, longer than wide; wings often undulate. Seeds inserted near base of capsule; wing pointing toward capsule apex.

About eight species: Cambodia, China, Laos, Myanmar, Thailand, Vietnam; seven species (four endemic) in China.