Tridynamia sinensis (Hemsl.) Staples

Two varieties with overlapping ranges along a broad zone in Guangxi and Guizhou provinces, where intermediates occur.

Climbers; indumentum reddish or dull yellow. Stems glabrous; young parts velutinous. Petiole 2.7-6.2 cm; leaf blade ovate to nearly circular, (4.4-)8.5-13.2 X (1.9-)6.1-10 cm, abaxially velutinous or glabrous, adaxially subglabrous. Bracts ovate-lanceolate; bracteoles unequal, persistent but not enlarging. Pedicel 1-1.6 cm. Flowers 8-10 mm. Sepals unequal, oblong; outer 2 sepals 4-5 mm, ± velutinous; inner 3 smaller, curved around ovary. Fruiting calyx tan to pale brown, oblong to spatulate; outer 2 sepals 6.5-7.8 X 0.9-1.4(-1.8) cm, sparsely velutinous, base tightly clasping, thickened, apex flat, winglike. Corolla blue-violet, pale blue, rose to white, bowl-shaped, outside velutinous; limb (1-)1.6-2.3(-3) cm in diam., ± 5-lobed; lobes reflexed. Stamens equal or unequal, (0.7-)1.1-1.2 cm; filaments not collared basally. Disc 5-lobulate or absent. Pistil exserted; ovary ovoid-conical, velutinous apically. Style (0.5-)0.9-1.1 cm, pubescent basally; stigma 2-globose. Fruit dark brown, reddish apically, ellipsoid-obovoid, 1-1.1 cm X 6-8 mm, ruminate, pilose, glabrous basally. Seeds dark brown to black, 9-10 X 6-8 mm, smooth or faintly striate.