Large woody climbers with white latex. Leaves opposite, petiolate; Inflorescence terminal, cymose, glabrous; Sepals deciduous; Stamens sessile; Fruit a pair of follicles, fusiform, slightly flattened, densely lenticellate. Seeds elliptic, flattened, without a terminal coma.
Asia-Tropical: Borneo present; Malaya (Peninsular Malaysia present); Sumatera (Sumatera present)
1 species from Sumatra, Peninsular Malaysia and Borneo.
The affinities of this genus are not very clear. Endress & Bruyns (), in their review of the Apocynaceae s.l., placed it in subfamily Apocynoideae, tribe Apocyneae. Amongst the members of this group it is unique in its weak attachment of the stamens to the style head and the lack of a coma on the seeds.