Climbing, or less often erect, glabrous herbs. Leaves cauline, alternate, opposite or in whorls of 3 (4), flat, with many veins and a strong midrib, sessile, entire, lanceolate to ovate, slightly amplexicaul, obtuse at the base, narrowing gradually to an apical, coiled tendril (sometimes lacking tendrils in erect forms); Ovary superior, sessile, oblong-ovoid to oblong-obovoid, 3-celled, 1 cell slightly shorter than the other 2; Capsule coriaceous, septicidal;
Asia-Tropical:, India ‒ present Burma: present Madagascar: present SE. Asia: present Tropical and southern Africa: present West Malesia: present
Widespread in tropical and southern Africa, Madagascar, India, Burma and SE. Asia, as far as West Malesia.
Stated by Field (1971, 1972) to be monotypic. In Malesia only a single indigenous species has ever been recognized, although other species have been described elsewhere.