Description from Flora of China
Trees with latex. Branches stout. Leaves in whorls of 3-5, rarely opposite; lateral veins numerous, subparallel, almost at a right angle to midvein. Cymes subterminal, pedunculate. Calyx deeply divided, usually without glands. Corolla salverform; tube slightly dilated above middle, to 1 cm, throat without scales; lobes overlapping to right. Stamens inserted in widening of corolla tube; anthers free from pistil head, narrowly oblong, rounded at base; disc absent. Ovaries 2, free or basally connate; ovules 2-6, biseriate on each side of a prominent placenta. Style filiform; pistil head shortly 2-cleft at apex. Drupes 1 or 2, smooth; endocarp thick, hard. Seeds 2-4 per locule, flat, not comose; endosperm none; cotyledons large, flat.
About 25 species: Malaysia, W Pacific Islands; three species cultivated in China.