On a roadside in NorCal, saw a plant that really surprised me. Sorry, no photo, but I'm hoping the description will be specific enough. The flowers very closely resembled scarlet pimpernel in both the cream of tomato soup color and form, but the center was slightly different. The flowers were perhaps 10% larger than scarlet pimpernel flowers. What really caught my eye was the foliage. Instead of the little egg-shaped leaves of scarlet pimpernel, these had leaves very similar to a cutleaf geranium! The seedhead was also different, more prominent.

I know most of the wildflowers, both native and introduced, in my area, but this was something I've never seen. Any guesses? Web searches not yielding any clues.