Leaf blades lobed or parted, segments undivided or lobed, margins crenate. Achene faces with fine transverse wrinkles. 2 n = 32. Flowering late winter-summer (Mar-Sep). Ponds, ditches and riverbanks; 0-700 m; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld., N.S., Ont., Que., Sask.; Ala., Ark., Calif., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., Wash., W.Va., Wis.; Europe. Ranunculus sceleratus var. sceleratus is a serious weed of watercourses and marshy fields. It is a naturalized weed in western North America; it is not clear whether it is native in the eastern part of the continent or was introduced from Europe.