Description from Flora of China
Trees, tall shrubs, or rarely subshrubs, often climbing when young. Branchlets tomentose, often spiny. Leaves opposite, simple, sometimes lobed, usually with large gland patches near base, often abaxially gray mealy. Inflorescences usually terminal cymes or panicles, sometimes 1-flowered in leaf axils; cymules axillary, decussate, few flowered, short; bracts leaflike. Calyx persistent, campanulate, enlarged in fruit, truncate, 4- or 5-dentate or lobed, often somewhat unequal or oblique, usually with large glands. Corolla zygomorphic, ventricose funnelform, tube narrow at base, throat wide; limb oblique, ca. 2-lipped, upper lip 2-lobed or entire, lower lip 3-lobed with middle lobe larger. Stamens 4, distinctly didynamous, inserted on basal part of corolla tube, usually included, sometimes slightly exserted; anthers divaricate, opening by longitudinal slits. Ovary (2-)4-locular; ovules pendulous or laterally attached, often with a central cavity. Style slender, usually unequally 2-lobed or stigma awl-shaped. Fruit a succulent drupe, endocarp bony, mesocarp fleshy. Seeds 4 or by abortion 2 or 3.
About 35 species: Asia, Australia, and New Guinea; seven species in China.