Rootstock of vertical tubers from a woody crown. Stem twining to left. Bulblets apparently absent. Leaves alternate, simple; leaf blade ± ovate, margin entire. Male inflorescence solitary, subspicate. Flowers solitary, subsessile or pedicellate; bracts borne at base of pedicels; perianth funnelform, lobes spreading; stamens 6, anthers introrse. Capsule not reflexed at maturity, often rather large, usually wider than long. Seeds inserted near middle of capsule, winged all round.

About seven species: Malaysia, extending into China, Indonesia, and Thailand; one species in China.