Shrubs, rarely small trees, 1–4.5(–15) m tall; young shoots usually ca. 5 mm in diam., green, glabrous. Petiole cylindric, 30–70 mm, glabrous; leaf blade thickly leathery, oblong to orbicular, 5–12.5 × 5.5–10.5 cm; base cordate-auriculate to rounded, the lobes often overlapping; apex obtuse or rounded; both surfaces usually glabrous; abaxial surface glaucous; adaxial surface green; midrib raised abaxially, grooved adaxially; lateral veins 10–14-paired, impressed adaxially. Inflorescence 7-or 8-flowered; rachis 15–25 mm, glandular. Pedicel 2.5–3.5 cm, puberulent, glandular; calyx ca. 1.5 mm, margin undulate, glandular; corolla campanulate, rose, 3.2–3.5 cm, glabrous; lobes 6–8, ovate, 1.3–1.5 × ca. 1.8 cm, emarginate; stamens 11–14, 1–2 cm, filaments glabrous; ovary conoid, ca. 8 × 2.5 mm, densely glandular-hairy; style ca. 1.8 cm, glabrous; stigma capitate, ca. 2 mm in diam. Capsule cylindric, curved, 22–30 × 5–6 mm. Fl. May–Jun, fr. Aug–Oct.