Rootstocks a cluster of fusiform roots. Stems twining to 1.5 m, glabrous. Petiole ca. 1 cm, pubescent along 2 lines; leaf blade lanceolate, 6-15 × 1-2.1 cm, membranous, puberulent adaxially and abaxially along midvein, base broadly cuneate, margin ciliate, apex caudate-acuminate; lateral veins ca. 7 pairs. Inflorescences 13-20-flowered; peduncle 0-6 (-10) mm, pubescent along 2 lines. Sepals subulate-lanceolate, ca. 5 mm. Corolla relatively uniformly pale when dried, 3-3.6 cm, glabrous outside; tube puberulent inside, inflated base 4-6 mm wide narrowing to 2-3.5 mm, widening to 5-8.5 mm at throat; lobes 1.3-1.9 cm, ovate and slightly revolute so open flowers are widest above throat. Outer corona lobes triangular, notched at apex; inner lobes, linear, longer than outer. Fl. Jun.

* Montane forests; 500-1000 m. Guangxi, S Yunnan.