Broad-leaved Marshmarigold, Broad-leaved Marsh-marigold, Howell's Marshmarigold, Twinflowered Marsh-marigold: Caltha biflora (Synonyms: Caltha biflora ssp. howellii, Caltha biflora var. biflora, Caltha howellii, Caltha leptosepala var. biflora, Caltha leptosepala ssp. howellii, Caltha leptosepala var. biflora) -
Broad-leaved Caltha, Broad-leaved Marshmarigold, Elkslip, Marsh Marigold, White Marsh Marigold: Caltha leptosepala (Synonyms: Caltha biflora var. rotundifolia, Caltha leptosepala var. leptosepala, Caltha leptosepala var. rotundifolia, Psychropila leptosepala) -
Western Marshmarigold, Yellow Marshmarigold, Yellow Marsh Marigold: Caltha palustris (Synonyms: Caltha arctica, Caltha asarifolia, Caltha palustris ssp. asarifolia, Caltha palustris var. asarifolia, Caltha palustris var. flabellifolia, Caltha palustris var. palustris) -