Ranunculus foeniculaceus Gilibert, Fl. Lit. Inch. 5: 261. 1782; Batrachium circinatum (Sibthorp) Spach; R. circinatus Sibthorp.

Herbs perennial, submersed. Stems up to 50 cm, branched, glabrous. Petiole 2--4 mm, sheath abaxially sparsely puberulent or glabrous; leaf blade orbicular in outline, 1--2.5 cm in diam., glabrous, 3-sect; segments 2 or 3 × sect, ultimate lobules filiform, ± rigid, remaining divaricate out of water. Flower 1--1.8 cm in diam. Pedicel 2.5--6.5 cm, glabrous. Receptacle conical in flower and fruit, puberulent. Sepals 5, elliptic, 3--4 mm, glabrous. Petals 5, white with yellow base, obovate, 5--10 × 4--6 mm, apex rounded. Stamens 17--25; anthers oblong, 0.7--1 mm. Aggregate fruit broadly ovoid, 3--4 × ca. 4 mm; achenes obliquely obovoid, ca. 1.2--1 mm, above sparsely puberulent or glabrous, with ca. 7 transverse wrinkles. Persistent style ca. 0.2 m. Fl. May--Sep.

Swamps, lakes; 300--3600 m. Gansu, Heilongjiang, Nei Mongol, N Shanxi, N Xinjiang, NW Yunnan (Zhongdian Xian) [Kazakhstan, N Mongolia, Russia (Siberia); Europe].