Lianas. Branchlets villous with long spreading trichomes, glabrescent. Stipules 1-1.5 cm. Leaves 19-35-foliolate; rachis 10-25 cm, including petiole 1.5-3 cm; stipels 4-5 mm; leaf blade oblong, 2.3-3.3 × 0.7-1.2 cm, papery, abaxially pubescent with appressed trichomes, adaxially sprinkled with whitish appressed trichomes, base rounded, apex rounded to obtuse and mucronate. Racemes 5-10 cm; bracts lanceolate-caudate, slightly keeled, 1.6-2 cm. Pedicel 7-10 mm; bracteoles 2-4 mm. Calyx 3-4 mm, with dense brown appressed trichomes. Corolla purplish; standard elliptic, 1.5-1.7 × ca. 1.1 cm, base subcordate, apex rounded. Ovary linear, ca. 1 cm, stipitate, with 6-10 ovules, glabrous. Legume 7-9 cm × 4-9 mm, 6-10-seeded, slightly constricted between seeds; stipe ca. 5 mm. Seeds bright blackish, ca. 6 × 3.5 mm; hilum broadly ovoid. Fl. Apr-May, fr. Jul-Aug.