Shrubs or small trees, to 3 m tall. Young branches zigzag, glabrous. Petiole 2.5-4 cm, pubescent; leaf blade ovate-cordate to cordate, 9-12 × 8-12.5 cm, subleathery, abaxially grayish pubescent, adaxially glabrous, primary veins 9-11, secondary and higher order veins protruding, base cordate, apex bifid to 1/3-2/5, lobes acuminate or slightly acute at apex or rarely rounded. Inflorescence a raceme, with few (3-15) flowers, axil­lary, appearing cymose; peduncle short, pubescent as inflores­cence axis; bracts and bracteoles linear, pubescent. Flower buds ca. 2.5 cm, acutely tapering and ending in 5 linear calyx teeth ca. 3 mm. Hypanthium tubular. Calyx spathe open on one side, shortly 5-toothed. Petals white, obovate-elliptic, 3.5-5 × ca. 2 cm, sessile. Fertile stamens 10 in 2 whorls, subequal, 1.5-2.5 cm, pubescent on lower 1/3; anthers yellow, oblong. Ovary prominently stalked, pubescent or almost glabrous; style 15-20 mm; stigma peltate, ca. 3 mm in diam. Legume straight or slightly curved, linear-oblanceolate, compressed, 6-12 × ca. 1.5 cm, with stalk ca. 1 cm, apex acuminate, beaked; valves leathery, glabrous, sharply ridged near suture. Seeds 5-12, com­pressed, 8-10 mm in diam. Fl. Apr-Jun, fr. Jun-Aug.

Guangdong, Guangxi, Yunnan [Cambodia, India, Indonesia, Laos, Malaysia (Peninsular), Philippines, Sri Lanka, Thailand, Vietnam].