Possibly an unspotted, miniature variant of Mimulus guttatus, Seep-spring Monkeyflower.

The location where this plant was found at Edgewood Preserve is similar
to the environment where M. guttatus is normally found, ie, very wet.

Note: "guttatus" means spotted, but none of the specimens found at this location
showed any spots. Some authorities regard this variant as a separate species, nasutus.