Herbs, 40-60 cm tall. Rhizome nodose, short, with numerous fibrous roots. Leaves basal and cauline, trifoliolate; leaflets lanceolate to narrowly lanceolate, 13-18 × 2.5-4 cm, thickly leathery, abaxially sparsely lanose, adaxially glabrous, base cordate, apex acuminate or long acuminate, terminal leaflet with subequal rounded lobes, lateral leaflets oblique with outer lobe large, cuneate and acuminate, inner lobe much smaller and rounded, margin spinose-serrate. Flowering stem with 2 opposite trifoliolate leaves, occasionally 3 leaves whorled. Panicle without conspicuous peduncle, many (up to 150) flowered, 30-35 cm, usually glabrous. Pedicel 1-2 cm, glabrous. Flowers ca. 6 mm in diam. Outer sepals caducous, purple, elliptic, ca. 3.5 × 1.5-3 mm; inner sepals white, ovate, ca. 2.5 × 1 mm. Petals yellow, obovate, ca. 2 mm, apex involute, without spur. Stamens ca. 4 mm; filaments ca. 1.5 mm; anthers ca. 2.5 mm. Pistil ca. 4 mm; ovules 3 or 4; style ca. 2.5 mm. Capsule ca. 1 cm; style ca. 4 mm. Fl. Mar-Apr, fr. Apr-May.