沾地毛茛 zhan di mao gen

Ranunculus gmelinii de Candolle var. radicans (C. A. Meyer) Krylov; R. hyperboreus Rottbøll var. radicans (C. A. Meyer) J. D. Hooker.

Herbs perennial, semiaquatic. Roots fibrous, subequally thick. Stems flaccid, glabrous or sparsely appressed puberulent, slightly branched above, rooting at nodes. Stem leaves with petiole 2--3(--8) cm, glabrous or sparsely puberulent; blade 3-partite, orbicular-reniform or cordate-pentagonal, 0.5--1(--1.6) × 0.7--1.7(--2.6) cm, herbaceous, glabrous or sparsely appressed puberulent, base cordate or cordate-truncate, central lobe rhombic-cuneate or broadly rhombic, 3-lobed, lobules entire, obtuse; lateral lobes obliquely flabellate, unequally 2-lobed nearly to middle. Flowers terminal or leaf-opposed, 0.6--0.7(--1.3) cm in diam. Pedicel 1--5 cm, glabrous. Receptacle sparsely puberulent. Sepals 5, ovate, 1.8--2.5 mm, glabrous. Petals 5, oblong-obovate, ca. 2.7 × 1.5 mm, nectary pit without a scale, apex rounded. Stamens ca. 13; anthers broadly ellipsoid. Aggregate fruit 3--5 mm in diam.; carpels numerous. Achene obovoid, 1--1.5 × ca. 0.8 mm, glabrous, margin with corky thickening; style persistent, ca. 0.3 mm. Fl. Jun--Jul.

Rivers or river banks. C and N Heilongjiang, N Nei Mongol, N Xinjiang [Mongolia, Russia (Siberia)].