Thanks for the info that led me to a specific plant name! I believe it is the Ozark Sundrop AKA Evening Primrose and yes you are right...of the Oenotherra family.
Thanks again!
Lisa
Yellow Flower with Green Elongated Leaves by: Susanne Inouye
This looks like a plant from the "primrose" family. There are many types like this with the yellow flower and different shaped leaves.Also known as the Oenothera family.