Herbs slender, twining. Cymes extra-axillary, short pedunculate, small, dense, irregularly branched. Flowers small. Calyx with 5 basal glands. Corolla urceolate, throat with a ringlike constriction at base of lobes; lobes twisted to right. Corona lobes 5 inserted on anthers, strongly laterally compressed, erect. Filaments connate into a tube; anthers with apical appendages; pollinia 2 per pollinarium, erect. Gynostegium as long as corolla tube; stigma head conical. Follicles linear-lanceolate, normally paired.

One species: southern China, Vietnam.