Description from Flora of China
Shrubs, sometimes low or reduced, unarmed, usually with short shoots. Raphides present. Leaves opposite, apparently without domatia; stipules persistent, interpetiolar, triangular, often aristate to spinescent. Inflorescences terminal on main stems and/or axillary short shoots (and then appearing axillary), capitate to congested-fasciculate or -cymose and several flowered or sometimes reduced to 1 flower, bracteate with bracts often fused in pairs. Flowers sessile to shortly pedicellate, bisexual, distylous. Calyx limb (4 or)5(or 6)-lobed. Corolla white to pink or purple, funnelform, inside glabrous to pubescent; lobes (4 or)5(or 6), valvate or valvate-induplicate in bud. Stamens (4 or)5(or 6), inserted in corolla throat, exserted or included; filaments short; anthers dorsifixed. Ovary 5-celled, ovules 1 in each cell, basal, erect, anatropous; stigmas (2 or)3-5(or 6), linear, exserted or included. Fruit capsular, ellipsoid to ovoid, opening through an apical operculum then splitting longitudinally into 5 valves, cartilaginous to woody, calyx limb persistent; aril reticulate, free or adherent to seed; seeds few, medium-sized, ellipsoid, straight, with thin testa; cotyledons rounded; radicle short, inferior.
About 40 species: Himalaya to Japan; 34 species (30 endemic) in China.
(Authors: Chen Tao (陈涛))