RHH's photos with the keyword: cymbalaria

I've identified these flowers as the Alkali Buttercup and that is the best I can do. They were blooming in The Ravines, a west Michigan park when photographed and they were everywhere in the wet areas of the park as the insets show.

These Buttercups were blooming everywhere in the wet areas of The Ravines, a park along the Grand River in west Michigan.

These, I believe, are Alkali Buttercups, photographed in The Ravines, a park along the Grand River in west Michigan. They were growing here with Skunk Cabbage.