Trees or shrubs, evergreen, bark and pith with white latex, domatia present. Leaves opposite, margin undulate or revolute. Cymes axillary or terminal, many flowered. Calyx deeply divided, with basal glands inside. Corolla salverform, tube swollen on 1 side at middle; throat much constricted, without scales; lobes overlapping to right. Stamens inserted near middle of corolla tube; anthers sagittate, included, adherent to pistil head, lobe with an empty tail; disc cup-shaped, deeply 5-cleft. Ovaries 2, free; ovules numerous, pendulous. Style glabrous; pistil head club-shaped. Follicles 2, divaricate. Seeds with a slender comose beak directed toward base of fruit.

Two species: tropical Africa, one cultivated in China.