Description from Flora of China
Prostrate herbs, climbing subshrubs or lianas. Stems sometimes thick corky, to 9 m, glabrous. Petiole 6-23 mm; leaf blade elliptic to narrowly elliptic or oblong, 4.5-13 X 2.2-5 cm, papery, glabrous, base broadly cuneate to cuneate, margin entire to denticulate with small glands, apex acuminate; lateral veins 4-6 on each side of midrib, abaxially prominent. Cymes 1-flowered; peduncle 1.4-2.8 cm, glabrous; bracts orbicular-ovate to ovate, 4-7 X 7-9 mm. Pedicel 2-7 mm. Calyx 1.6-2.2 cm, 5-lobed from above middle; tube 1.2-1.8 cm; lobes 4-5 X ca. 5 mm, glabrous. Corolla white or tinged greenish, ca. 4 cm, outside glabrous, inside puberulent basally; tube slender funnelform, ca. 3.3 X 1.2-1.4 cm; adaxial lip ca. 6 mm; abaxial lip ca. 7 mm. Stamens ca. 1.3 cm; filaments ca. 1 cm; anthers oblate; connective unappendaged; staminodes 2, ca. 2 mm. Disc ringlike, margin entire. Pistil ca. 2.5 cm, glabrous. Capsule 6.5-9 cm. Seed appendages subulate, 0.3-0.5 mm. Fl. Jul-Sep, fr. Sep.
On trees and rocks in forested valleys; 900-1500 m. S and W Guangxi, SE Yunnan [N Vietnam].