August 20, 2020 Oenothera deltoides ssp. howellii Antioch Dunes Evening-primrose Antioch Dunes evening primrose (Oenothera deltoides ssp. howellii) at Antioch Dunes National Wildlife Refuge. Photo by James Gorham, CC BY-NC 4.0. Additional Resources U.S. Fish & Wildlife Service Antioch Dunes Evening Primrose page California Dept. of Fish and Wildlife endangered species page