Plants of this genus are popular aquatics for cultivation, and many cultivars of species from all over the world are grown for colorful flowers and for the variegated leaves of some forms.
1. Flowers ca. 5 cm or less across, opening in the afternoon; sepals ca. 3 cm or shorter at flowering time, becoming a little longer and stiffly erect over the fruit; stigmas 10 or fewer; leaf blades small (usually less than 7 cm broad), ca. 1.3–1.5 times as long as wide, with sinus extending half their length.
1. Flowers more than ca. 5 cm across (except in dwarf bogpool forms), opening early in the morning; sepals over 3 cm long, curving over the fruit; stigmas more than 10; leaf blades ordinarily more than 7 cm broad, at most about 10% longer than wide, with sinus extending less than half the length.
All species found in Nymphaea
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 19, 2018. https://michiganflora.net/genus.aspx?id=Nymphaea.