Rocky Mountain Pond-lily, Spatterdock, Wakas, Yellow Pond Lily, Yellow Water-lily: Nuphar polysepala (Synonyms: Nuphar lutea, Nuphar lutea ssp. polysepala, Nuphar polysepalum, Nymphaea polysepala, Nymphozanthus polysepalus) - 5-12 large, showy yellow to greenish sepals. The petals are not showy. Ovary superior.
American Water-lily, American White Waterlily, Fragrant Water Lily, White Water Lily: Nymphaea odorata ssp. odorata (Synonyms: Castalia lekophylla, Castalia minor, Castalia odorata, Castalia reniformis, Nymphaea minor, Nymphaea odorata var. gigantea, Nymphaea odorata var. godfreyi, Nymphaea odorata var. minor, Nymphaea odorata var. rosea, Nymphaea odorata var. stenophetala, Nymphaea odorata var. villosa) - 4 greenish sepals, as large as the petals but less showy. Numerous petals are white to pinkish. Ovary partially inferior.