Description from Flora of China
Delavaya yunnanensis Franchet.
Shrubs or small trees, 3-8 m tall. Bark brownish red; branches slightly grooved, glabrous. Petiole 3-4.5 cm; leaflets thinly leathery; middle one elliptic or ovate-elliptic, sometimes lanceolate-ovate, 8-15 × 1.5-4.5 cm, base cuneate, with stalk ca. 1 cm, apex long acuminate; lateral ones smaller, ovate or lanceolate-ovate, subsessile, margin somewhat thickly serrate, rarely entire, glabrous; lateral veins slender, slightly prominent on both sides. Inflorescences narrow, slender, sparsely flowered. Pedicels 5-10 mm. Sepals suborbicular, concave, larger ones 4-5 mm, glabrous. Petals white or pink, narrowly elliptic or obovate, ca. 8 mm; scale broadly obovate, cuneate or square, upper part fimbriate. Filaments glabrous. Ovary glabrous or sparsely glandular hairy. Capsules royal purple, lobes 1.5-2.5 cm or slightly longer. Seeds 1-1.5 cm in diam. Fl. Apr, fr. Aug.
Dense forests; 500-2000 m. Guangxi, Yunnan [N Vietnam].