Helianthus anomalus, the western sunflower, is a species of plants in the sunflower family, found in the southwestern United States. Helianthus anomalus is of particular interest due to its genetics. It was produced via hybridization of two other sunflower species, H. annuus and H. petiolaris, multiple times between approximately 60,000 and 200,000 years ago. From these two parent plants, three hybrids were formed, each with distinct characteristics and habitat preferences.