Annual herb, c. 5-15 cm tall, commonly with many branches from the base, branches glabrate or sparsely pubescent, hairs white and black. Leaf imparipinnately compound, c. 2-10 cm long, petiole short, rachis sparsely pubescent, hairs white and black; leaflets 11-19, c. 5-11 mm long, oblong to linear, entire, retuse, sparsely villosulous or hirsute on both sides; stipules c. 2.5-3.5 mm long, beset with white and black hairs or glabrate. Inflorescence a 1-5-flowered raceme. Bracts 1-2.5 mm long, glabrous to subglabrous. Flowers subpedicellate. Calyx c.3-5 mm long, black and white pubescent, teeth c. 0.5-1 mm long. Corolla violet. Vexillum c. 6-8 mm long. Wing c. 5-6 mm long. Keel c. 5-6 mm long. Fruit sessile, c. 2-5 cm long, c. 2.5-3 mm broad, arched-incurved, glabrous with prominent reticulate ridge, beak hooked, 14-20-seeded.