This genus is accepted, and its native range is Congo to Tanzania and S. Africa.
Shrub or tree with white or yellow latex.
Branchlets usually dotted with paler lenticels.
Leaves opposite or rarely subopposite, those of a pair equal, often fairly long-petiolate.
Inflorescence thyrsoid, terminal and in axils of the upper leaves, lax to congested; bracts obscure.
Flowers actinomorphic except for the sometimes slightly unequal sepals.
Sepals ovate, acute, connate at the base.
Corolla hypocrateriform; tube usually much longer than the calyx, nearly cylindrical, ventricose in the upper half and constricted at the mouth, inside velutinous to sericeous except for the glabrous base; lobes narrowly oblong or narrowly obovate, inside at the base pilose or sericeous, overlapping to the left in bud, spreading.
Stamens included; inserted near the middle of the corolla tube; filaments filiform, much widened at the apex; anthers triangular, completely fertile, mucronate, sagittate at the base.
Ovary of two basally connate carpels; 4 ovules on an adaxial placenta in each carpel; clavuncula subcylindrical.
Fruit composed of two obliquely oblong follicles, outside dotted with many paler lenticels, dehiscent at the adaxial side.
Seeds laterally compressed, obliquely oblong, long-winged at the apex; wings of the two outer seeds directed towards the base and those of the two central seeds towards the apex of the fruit.
Seeds compressed, obliquely oblong, dorsal side straight, ventral side abruptly curved, long-winged at apex.
in Trans. Linn. Soc., Ser. 2, Bot. 2: 22 (1881).