Annual or short-lived perennial, villous, 0.3–1.3 m tall. Leaf-rhachis up to 10 cm long, including a petiole of up to 1 cm. Leaflets 9–15, cuneate-oblong or elliptic, up to 35 x 12 mm, densely appressed villous beneath, more sparsely so above. Flowers purple in terminal pseudoracemes, often also in the upper leaf-axils. Calyx densely villous with long-acuminate lobes, the lowest up to c. 8 mm long. Standard villous with brownish hairs, up to 11–15 mm long. Style glabrous, up to 3–5 mm long, bent sharply upward at base, twisted, penicillate. Pods ± deflexed, strongly upcurved near the tip, up to 54 x 5–6 mm, densely villous. Seeds 6–12, c. 4 x 2.5 mm.