Isopyrum fumarioides Linnaeus, Sp. Pl. 1: 557. 1753.

Stems (2--)4--9(--17), 8--30 cm tall, sparsely branched, glabrous or subglabrous. Basal leaves glabrous; petiole 2.5--13 cm; leaf blade triangular-ovate, 0.8--2.7 × 1--3 cm; lateral leaflets sessile, unequally divided; central leaflet petiolule slender; leaflet blade rhombic, ca. 1.2 × 1.1 cm, 3-sect; segments narrowly elliptic-obovate to linear-obovate, margin entire or sparsely obtusely toothed. Stem leaves shortly petiolate, similar to basal leaves but smaller. Flowers 3--5 mm in diam. Pedicel 0.3--3 cm, glabrous. Sepals yellowish, elliptic, 3--4.5 × 1.2--2 mm, apex acute or obtuse, 3-veined. Petals ca. 1 mm, glabrous. Stamens ca. 3 mm; anthers ca. 0.5 mm. Pistils ca. 2 mm, glabrous. Follicles linear-ellipsoid, 8--10 mm, glabrous. Seeds ovoid to narrowly ovoid, 0.5--0.7 mm. Fl. May--Jul, fr. Jun--Jul.

Forest margins, grassy places, by fields; 100--1400 m. Gansu, Hebei, Heilongjiang, Jilin, Liaoning, Nei Mongol, Ningxia, E Qinghai, Shaanxi, Shanxi, Xinjiang [Kazakhstan, Korea, Mongolia, Russia (Siberia)].