Description from Flora of China
Climbers, with tendrils. Young branches reddish pubescent, later glabrous. Stipules linear, ca. 4 mm; petiole sparsely pubescent, (1-)2-4 cm; leaf blade ovate to orbicular, often broader than long, 4-6(-9) cm in diam., abaxially sparsely pubescent, adaxially glabrous, 7-11-veined, base truncate to cordate, apex bifid to 1/5-1/2, tip of lobes rounded. Flowers in short dense corymbs; bracts linear, ca. 5 mm; bracteoles similar, inserted near middle of pedicel. Pedicel slender, 10-20 mm. Flower buds ovoid, glabrous to hairy. Receptacle striate, tubular, 7-15(-30) mm, subglabrous. Calyx splitting into 2 or 3 reflexed segments. Petals white, subequal, broadly obovate, 8-12 mm including claw 2-3 mm. Fertile stamens 3; filaments glabrous, ca. as long as petals; anthers red, ellipsoid, ca. 2 mm. Staminodes 7, 2 in between stamens, ca. 3 mm, 5 short, subulate, connate at base. Ovary ca. 8 mm, glabrous, shortly stalked; style very short; stigma obliquely peltate. Legume flat, 18-25 × 3-5 cm, thinly valved, indehiscent. Seeds flat, ovoid, 5-8 mm.
Guangdong, Guangxi, Guizhou, Hubei, Hunan, Shaanxi, Yunnan [Cambodia, India, Indonesia, Laos, Malaysia (Peninsular), Myanmar, Thailand, Vietnam].