Oenothera rubricaulis (evening primrose)
Image: Oenothera rubricaulis (evening primrose) | CC-PD | Date: 6 July 2014 | Author: George Chernilevsky | Source: Wikimedia Commons in the public domain | https://commons.wikimedia.org/wiki/File:Oenothera_rubricaulis_2014_G1.jpg