Erect or suberect perennial herb, (10-) 15-30 (-45) cm tall, leafy, simple or sparsely branched; rootstock thick, often branched with branches twisted together, densely covered with withered sheathing leaf bases. Radical leaves usually large and reaching the base of the inflorescence, 10-20 cm long, 4-6 cm broad, 3-pinnatisect, with 5-8 (-10) pairs of opposite or subpopposite pinnae and a terminal one; lateral pinnae often unequal in size, 2-5 cm long, 1-2.5 cm broad, shortly petioluled to subsessile, with deeply dissected few, alternate pinnules, up to 2 cm long and 1 cm broad, much dissected into many lobules (ultimate segments) ; lobules very narrow, linear or capillary, up to 10 mm long, 1 mm broad, tapering, acute, glabrous; cauline leaves similar but becoming smaller upwards, shortly petioluled to sessile. Racemes 3-5 cm long, 15-20 (-30)-fld., subcorymbose; bracts deeply dissected or pectinate, up to 2 cm long, but gradually becoming smaller and less dissected above. Flowers 12-18 mm long, including short spurs, less than half as long, yellow with purple or violaceous tips. Pedicels of the lower flowers longer, about as long or slightly longer than bracts, ascending but down-curved in fruits. Sepals minute, inconspicuous. Upper petal limb with conspicuous, pub-orbicular dorsal wing, obtuse, about twice as long as the short, obtuse, straight spur; spur 4-6 mm long, 2.5-3 mm broad; lower petal somewhat saccate at base, narrower than the upper petal. Capsule oblong-ellipsoid, 7-10 (-12) mm long, 3-4 mm broad, 4-6-seeded; style 3-4 mm long, curved at the apex with broad stigma; seed c. 2 mm in diam., shining black.