Description from
Flora of China
Heterostemma villosum Costantin var. menghaiense H. Zhu & H. Wang.
Lianas. Internodes yellow pilose, hairs retrorse, especially near nodes. Petiole to 2.8 cm, densely pilose; leaf blade ovate, ca. 8 × 6.5 cm, densely yellow pubescent to pilose, base truncate to shallowly cordate, apex acuminate; basal veins 5, lateral veins 3 or 4 pairs. Inflorescences subsessile, umbel-like, few flowered; all parts up to sepals densely pubescent, almost tomentose. Pedicel to 2.3 cm. Sepals oblong-triangular, ca. 2.4 × 1.7 mm, apex rounded. Corolla yellow with purple dots, rotate, ca. 2 cm in diam.; densely puberulent outside, glabrous inside, smooth; limb ca. 1 cm in diam.; lobes ovate-triangular, ca. 6.5 × 6 mm, apex subacuminate. Corona raised in center; lobes oblong-ovate, ca. 2.5 × 1.4 mm, without any dorsal appendages, outer margin rounded, inner tooth rounded, largely concealing gynostegium. Fruit not seen. Fl. Jun.
* In thickets near streams; 1000-2000 m. Yunnan.