Ranunculus polyrhizos Stephan ex Willdenow var. major Maximowicz; R. ussuriensis Komarov.

Herbs perennial. Roots fibrous, slightly thickened at plant base. Stems 3--5, flaccid, 7--20 cm, glabrous, simple or 1-branched above. Basal leaves ca. 10; petiole 4--14 cm, glabrous; blade 3-sect or 3-partite, reniform or semiorbicular, 1--2 × 1.8--3.9 cm, herbaceous, abaxially glabrous, base broadly cordate or subtruncate, central segment broadly obovate, 3--5-lobulate; lateral segments oblique, broadly obovate or flabellate, unequally 2-lobed. Stem leaves ca. 2, sessile, 3-sect, segments usually petiolulate. Flowers solitary, terminal, (1--)1.2--1.8 cm in diam. Receptacle glabrous. Sepals 5, elliptic, 4--6 mm, abaxially appressed puberulent. Petals 5, obovate, (6--)7--8 × 4--7 mm, nectary pit without a scale, apex rounded or subtruncate. Stamens numerous; anthers oblong. Aggregate fruit ovoid or subglobose, 5--8 mm in diam. Achene slightly bilaterally compressed, subglobose, ca. 1.5 × 1.5 mm, densely puberulent; style persistent, ca. 1 mm, curved at apex. Fl. Apr--May.

Forest or forest margins; 300--1300 m. Heilongjiang, C and E Jilin, E Liaoning [N Japan, N Korea, Russia (Far East)].