Plants 30-80 cm tall, with subappressed hairs 0.2-0.6 mm. Stems solitary or several, 1-3 mm thick, in lower 1/2 or 2/3 leafless, loosely hairy. Leaves 5-12 cm; stipules membranous, 4-8 mm, with ± spreading black and white hairs; petiole short, like rachis subappressed white and black hairy; leaflets in 4-8 pairs, narrowly ovate to narrowly elliptic, 8-35 × 1-5(-8) mm, abaxially subappressed white hairy, adaxially glabrous, apex obtuse to subacute. Racemes 3-7 cm, rather densely 4-20-flowered; peduncle 4-11 cm, subappressed white and black hairy; bracts membranous, narrowly elliptic, 5-7 mm, white hairy. Calyx campanulate, 5-6 mm, densely covered with subappressed, predominantly brownish to blackish hairs; teeth nearly equal, 1-2 mm. Petals blackish purple; standard widely rhombic-elliptic, ca. 11 × 7 mm; wings ca. 10 mm; keel ca. 9 mm. Ovary with a style shortly hairy below stigma. Legumes with a stipe 4-5 mm, ovoid to ellipsoid, 15-30 mm, 5-6 mm high and wide; valves thinly membranous, loosely covered with ascending to spreading black hairs 0.1-0.3 mm.
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