The flower looks like Ratibida columnifera, but there are no pinnatifid leaves. Perhaps it bloomed with only juvenile foliage? Plants in Asteraceae do strange things like that. Did the plant get adequate sunlight?

Thanks for the idea, but no, there were many of them, all of them the same leaves, smooth not at all hairy, they bloomed all the same with these leaves.

They were outside all the time. I once grew Ratibida columnifera from seed and even the tiniest seedlings had bipinnatifid leaves and were rough to the touch.

I didn't know about Rudbeckia amplexicaulis. Thanks!

Yes it is! Thank you.