Description from Flora of China
Herbs perennial, (8-)15-30(-40) cm tall. Rhizomes creeping, sparsely scaly, not stoloniferous. Stems simple, erect, strongly curved at base, glabrous throughout or sparsely pilose distally. Rhizomal leaves 7-16(-22) cm; petiole 3.5-8(-12) cm; terminal leaflet oblong, oblong-lanceolate, or elliptic, (2-)3-5(-6) × 0.7-1.2(-2) cm, sessile, base cuneate, margin serrate and ciliolate, apex acute to subobtuse; lateral leaflets 3-5(or 6) pairs, not decurrent at base. Cauline leaves 1-3(-5), (3-)5-10(-13) cm, subleathery; petiole (0.5-)1-2.5(-4) cm, not auriculate at base; terminal leaflet oblong, 2-4 cm × 3-10(-15) mm, subsessile, glabrous or rarely sparsely pilose, base cuneate, margin ciliolate and serrate, rarely subentire or doubly serrate, apex acute or acuminate; lateral leaflets 2-4 pairs, similar to terminal but slightly smaller, not decurrent at base. Racemes 10-15-flowered. Fruiting pedicels ascending or divaricate, (0.7-)1-1.5 cm, straight, slender. Sepals oblong, 4-5 × (1-)1.5-2 mm, base of lateral pair saccate. Petals purple, spatulate, 0.8-1.4 cm × (2-)3-5 mm, base not clawed, apex rounded. Median filament pairs 6-8 mm, lateral pair 5-6 mm; anthers oblong, 1.2-2 mm. Ovules 10-14 per ovary. Fruit linear, 3.5-4.5 cm × 2-3 mm; gynophore to 2.5 mm; valves smooth, glabrous; style 2-4 mm. Seeds brown, ovate or suborbicular, 2-2.8 × 1.5-1.8 mm. Fl. May-Jul, fr. Jun-Aug. 2n = 42*.
Although Schulz placed Cardamine tangutorum in a section different from that of C. macrophylla, the two species, if indeed distinct, are very closely related and are often difficult to separate. The separation in the key above is tenuous, and a critical study of the complex might prove that the two are conspecific.
This species is used medicinally and eaten as a vegetable.
* Montane ditches, swampy meadows, river basins, woodlands; 1300-4400 m. Gansu, Hebei, Qinghai, Shaanxi, Shanxi, Sichuan, Xizang, Yunnan.