1. Stems creeping or floating, rooting at nodes; flowers whitish; sepals ca. 4–8 mm long.
C. natans
1. Stems ± erect, not rooting at the nodes; flowers bright yellow; sepals ca. 11–27 mm long.
C. palustris
All species found in Caltha
Citation:
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. April 20, 2019. https://michiganflora.net/genus.aspx?id=Caltha.