Habit and leaf form. Shrubs; deciduous. Leaves opposite; petiolate to subsessile; simple. Leaf blades dorsiventral; dissected, or entire; ovate; when dissected, pinnatifid; pinnately veined; cross-venulate. Leaves without stipules. Leaf blade margins entire, or serrate, or dentate. Vegetative buds scaly. Leaves without a persistent basal meristem. Domatia recorded, or not recorded. Leaf anatomy. Hairs present; complex hairs present. Complex hairs peltate. Stem anatomy. Nodes unilacunar. Secondary thickening developing from a conventional cambial ring.
Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence and flower features. Flowers solitary, or aggregated in ‘inflorescences’; in panicles. The terminal inflorescence unit (when flowers aggregated) cymose. Inflorescences terminal, or axillary. Flowers bracteate, or ebracteate; fragrant; regular; 4 merous; tetracyclic. Free hypanthium absent. Hypogynous disk present (around the gynoecium), or absent; extrastaminal. Perianth with distinct calyx and corolla; 8; 2 -whorled; isomerous. Calyx present; 4; 1 -whorled; gamosepalous; sub- entire, or lobed; valvate; regular; persistent. Corolla present; 4; 1 -whorled; gamopetalous (funnel- to salver-shaped). Corolla lobes markedly shorter than the tube. Corolla valvate; regular; white, or purple, or red. Androecial members definite in number. Androecium 2. Androecial sequence not determinable. Androecial members adnate (to the corolla); free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 2; becoming exserted, or remaining included; reduced in number relative to the adjacent perianth; oppositisepalous; all alternating with the corolla members; filantherous, or with sessile anthers. Anthers dorsifixed, or basifixed; dehiscing via longitudinal slits; introrse. Gynoecium 2 carpelled. The pistil 2 celled. Carpels reduced in number relative to the perianth. Gynoecium syncarpous; synovarious to eu-syncarpous; superior. Ovary plurilocular; 2 locular. Gynoecium median, or oblique, or transverse; stylate. Styles 1; apical. Stigmas 2 - lobed; dry type; papillate, or non-papillate; Group II type. Placentation axile. Ovules (1–)2(–50) per locule; pendulous, or ascending; with dorsal raphe; collateral; non-arillate; anatropous, or amphitropous.
Fruit and seed features. Fruit non-fleshy; dehiscent; a capsule. Capsules loculicidal. Fruit 1–4 seeded. Seeds endospermic, or non-endospermic. Endosperm oily. Seeds winged. Embryo rudimentary at the time of seed release, or weakly differentiated to well differentiated. Cotyledons 2. Embryo achlorophyllous; straight. Seedling. Germination phanerocotylar, or cryptocotylar.
Geography, cytology, number of species. Adventive.