in G. W. Clinton, Rep. (Annual) Regents Univ. State New York State Cab. Nat. Hist. 19: 73. 1866 (as variegatum)
Phenology: Flowering late spring–summer.
Habitat: Ponds, lakes, sluggish streams, and ditches
Elevation: 0-2000 m
St. Pierre and Miquelon, Alta., B.C., Man., N.B., Nfld., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon, Conn., Del., Idaho, Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., Mont., Nebr., N.H., N.J., N.Y., N.Dak., Ohio, Pa., R.I., S.Dak., Vt., Wis.
Nuphar variegata is distinct throughout most of its range. The leaves are characteristically floating, being emergent only under low-water conditions. Intermediates between N. variegata and N. microphylla, probably of hybrid origin, are treated as N. rubrodisca. Some intergrading of characteristics occurs where the range overlaps with N. advena (E. O. Beal 1956). This can be observed in the mid-Atlantic region. Intermediates between N. variegata and N. polysepala occur in eastern British Columbia where the two species are sympatric. Authorship and typification of this name were discussed by E. G. Voss (1965).