Shrubs climbing. Stems terete, striate, densely white tomentose. Petiole 2-6 cm, densely tomentose; leaf blade narrowly ovate to ovate-oblong, 7-20 × 3.5-10 cm, leathery, abaxially densely white villous, adaxially glabrous, veins pinnate, 4 or 5 pairs, base cordate, sinus 1-2 × 1-2 cm, apex acute to acuminate. Racemes cauliflorous, often on old woody stems, 3-5-flowered, rachis short. Pedicel ca. 1.5 cm, pendulous, pubescent; bractlets subulate to lanceolate, 2-3 mm. Calyx limb purple-red, 4-5 cm; tube geniculately curved, abaxially densely white villous; basal portion of tube ca. 20 × 8 mm; limb discoid-rounded, 2-2.5 cm in diam., shallowly 3-lobed; lobes broadly deltoid, abaxially papillate near base. Anthers oblong, ca. 2 mm. Gynostemium 3-lobed. Capsule not seen. Fl. Jun-Apr.