Description from Flora of China
Trees to 20 m tall. Branches dark brown, densely tomentulose when young, glabrescent, densely lenticellate. Petiole 4-8 mm, tomentose to glabrescent; leaf blade elliptic to ovate, 3-7 × 1.2-3 cm, papery, abaxially tomentulose, adaxially appressed pubescent, secondary veins 6 or 7 on each side of midvein, base obtuse to rounded, apex obtuse to shortly acuminate. Inflorescences axillary, 1-flowered. Flower buds lanceolate, with 3 longitudinal ribs. Flower ca. 2 × 0.5-0.8 cm, recurved. Pedicel 2-3 mm, tomentulose, bracteolate at apex. Calyx shallowly 3-lobed; sepals broadly ovate, ca. 4 × 4 mm, outside densely tomentulose, inside glabrous. Outer petals lanceolate, ca. 15 × 3 mm, concave, thick, woody when dry, tomentulose; inner petals linear-lanceolate, ca. 14 × 2 mm, tomentulose, with adaxially elevated central rib. Stamens oblong, ca. 2.5 mm; anther locules transversely septate; connectives narrowly 3-angular, pubescent. Carpels ca. 4 mm, densely villous; styles slender; stigmas clavate, villous. Monocarp stipes ca. 1.5 cm; monocarps oblong, 2.5-3.5 × 0.8-1 cm. Seeds 3-8 per monocarp, ovoid. Fl. Mar-Jun, fr. Jun-Oct.
Forested slopes; 400-700 m. S Guangxi [Cambodia, N Thailand, Vietnam].