Description from Flora of China
Shrubs or trees, deciduous, 1.5–5 m tall. Twigs subglabrous. Leaf petiole 0.5–1.5 cm, pubescent, hispidulous, or glabrous; leaf blade elliptic, obovate-elliptic, or oblong-elliptic, 3–7 × 1.5–3 cm, thinly papery, abaxially hispidulous on veins or glabrescent, adaxially sparsely shortly setulose and puberulous on veins or glabrous, midvein raised abaxially, adaxially slightly impressed, secondary and fine veins slender and inconspicuous, base cuneate to broadly cuneate, margin serrulate, apex acute. Inflorescence corymbose-racemose; rachis to 5–7 cm, many flowered, densely pubescent or scattered glandular pubescent. Pedicel flattened, terete, 1.5–3 cm, slender, densely pubescent, with glandular hairs or not. Calyx ciliolate; lobes ovate-triangular, 2–3 mm. Corolla white, brick red, or pale yellow, broadly campanulate, 0.8–1.5 cm; lobes erect, broadly triangular. Filaments puberulous. Ovary shortly setulose, pubescent, or glabrous; style pubescent to glabrous. Capsule pendulous, 5–7 mm; stalk erect or distinctly recurved, 2.5–3.5 cm. Fl. Apr–Jul, fr. Jun–Jul.
Pinus or Quercus forests, mixed forests on mountain slopes, disturbed forests, thickets; 1000–3300(–3900) m. S Gansu, Guizhou, Guangdong, Hubei, Sichuan, Xizang, Yunnan [Bhutan, NE India (Darjiling), Myanmar, Nepal, Sikkim].