Description from Flora of China
Unona dumosa Roxburgh, Fl. Ind. 2: 670. 1824.
Climbers to 4 m tall, woody. Branches densely hairy when young. Petiole 5-10 mm; leaf blade obovate-elliptic to oblong, 5-16 × 2-7 cm, membranous to thinly papery, abaxially densely erect hairy, secondary veins 9-15 on each side of midvein, base shallowly cordate to truncate, apex shortly acuminate to acute. Inflorescences extra-axillary or leaf-opposed, 1-flowered. Pedicel 1-3 cm. Flowers pendulous. Sepals ovate to lanceolate, 4-11 × 2.5-6.5 mm. Outer petals ovate to obovate, 4-6.5 × 1.5-3.5 cm; inner petals ovate to lanceolate, 3-4(-6.5) × 0.5-0.8(-2) cm. Stamen connectives apically truncate to rounded. Carpels many; stigmas clavate, apex 2-cleft. Fruiting pedicel 2-4 cm; monocarp stipes 4-7 mm; monocarps ellipsoid or moniliform, 0.8-5.5 × 0.5-0.8 cm, sparsely to densely hairy. Fl. Apr-Aug, fr. Jul-Apr.
Open forests, thickets; 500-1700 m. Guangxi, Guizhou, S Yunnan [Bhutan, India, Laos, Singapore, Thailand, Vietnam].