Description from
Flora of China
Trees or shrubs, with aerial roots. Stipules reddish, sessile, leaflike, lanceolate. Leaves opposite or distichous; leaf blade glabrous, midvein extended into a caducous point, margin entire or serrulate near apex. Inflorescences axillary, dense cymes. Bracteoles forming a cup just below flower. Calyx tube adnate to ovary, persistent; lobes 5-8. Petals 4, lanceolate. Stamens 8-12; filaments much shorter than anthers or absent; anthers introrse, locules many, dehiscing by an adaxial valve. Ovary inferior, 2-loculed, apically partly surrounded by a disk, free part elongating after anthesis; style 1, sometimes very short; stigmas 4. Fruit brown, ovoid, ovoid-conic, or pyriform. Fertile seed 1 per fruit; germination viviparous; hypocotyl protruding to 78 cm before propagule falls.
Eight or nine species: tropics and subtropics; three species in China.