Herbs, 38-42 cm tall. Rhizome creeping, elongated, ca. 8 cm or longer, slender, 1.5-2 mm in diam. Leaves basal and cauline, trifoliolate; leaflets adaxially green, narrowly ovate, 4-6 × 2-3 cm, leathery, abaxially glaucous, with scattered minute erect hairs, adaxially glabrous, base shallowly cordate, with narrow sinus and basal lobes rounded or acute, lateral leaflets conspicuously oblique with outer lobe large, inner lobe smaller, margin closely spinulose-subserrulate, apex acuminate. Flowering stem with 2 opposite or alternate leaves. Panicle 5-30-flowered, 9-30 cm, with lower peduncles 2-5-flowered. Pedicel 1.5-2 cm, glandular hairy. Flowers large, 4-6 cm in diam. Outer sepals caducous, white with purple tinge, ca. 4 mm; inner sepals appressed, white or reddish, narrowly ovate, ca. 6 × 2.5 mm, apically acute. Petals pale yellow, much longer than inner sepals; spur curved, subulate, elongated, 2-3.5 cm, lamina-less. Stamens nearly enclosed, pale yellow, ca. 3.5 mm; filaments ca. 1.5 mm; anthers ca. 2 mm, valved. Pistil ca. 4.3 mm. Capsules ca. 2.5 cm; style ca. 7 mm. Fl. Apr, fr. Jul.