Buttercups are famously intensely yellow. Except that sometimes the petals turn white as they age. And except for the slightly darker base of the petals, which are an area of intense ultraviolet. This area can be seen by pollinators, and helps guide them to their target. I once heard it described as guidelines on the landingstrip. These flowers are about an inch across. Swamp buttercup grows in low shady areas in AL, AR, CT, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, NC, ND, NE, NH, NJ, NY, OH OK, PA, RI, SC, SD, TN, TX, VA, VT, WI, WV, LB, MB, NB, NT, ON, PE, and QC. Lenawee Co MI, 5/10/17.