Subshrubs or perennial herbs, small, to 1 m tall, adpressed hairy throughout. Leaves 3-foliolate; petiole 0.5-1 cm; leaflets oblanceolate, linear-oblong, or narrowly oblong, terminal one 1.5-3.5 × 0.2-0.7 cm, base attenuate, margin slightly involute, apex acute or obtuse-rounded, mucronate. Racemes axillary, slightly overtopping leaves, 3-7-flowered. Calyx narrowly campanulate, 5-parted; lobes lanceolate, distinctly 3-veined after fruiting. Corolla white or yellowish; standard with purple spots at base, not or rarely reflexed at fruiting; keel mixed with purple at apex; standard and wings subequal to keel, sometimes standard short. Cleistogamous flowers clustered in leaf axils, subsessile. Legume broadly ovoid, slightly overtopping persistent calyx, both surfaces adpressed white hairy. Fl. Jul-Sep, fr. Sep-Oct. 2n = 20.