Vines woody. Stems to 5 m, glabrous. Leaves simple, glabrous; petiole 3.7--7 cm; leaf blade broadly ovate, 4.5--10 × 3.5--6 cm, thick papery, base subcordate, margin denticulate, apex ± obtuse; basal veins prominent on both surfaces. Cymes racemelike, 5-flowered, glabrous; peduncle 3.5--5.5 cm; bracts foliaceous. Flowers ca. 7 cm in diam. Pedicel 5--10 cm. Sepals 6, white, spreading, narrowly oblong, 2.5--3.5 × 0.3--0.5 cm, abaxially reddish brown velutinous, adaxially glabrous, margin gray velutinous, apex obtuse. Outer stamens becoming staminodes, glabrous; outermost staminodes narrowly linear, slightly longer than sepals, 1--2 mm wide; inner staminodes linear, 1.2--1.5 cm; inner stamens fertile, ca. 1 cm, puberulous; anthers narrowly oblong, ca. 5 mm, apex apiculate. Ovaries puberulous. Style ca. 8 mm, densely villous. Fl. Apr.

* Forests on limestone hills; ca. 800 m. SE Guizhou (Libo Xian).