Hybridization of the San Francisco Peaks' rare endemic Packera franciscana with a lower-elevation congener: Evidence from morphometric and molecular data

Morphometric and molecular data are presented that support the hypothesis that the rare endemic Packera franciscana (San Francisco Peaks groundsel) is hybridizing with another Packera species, Packera werneriifolia, which occurs at a lower elevation on the San Francisco Peaks near Flagstaff, Arizona. The morphological data show that most individuals from Snowslide Spring have an intermediate appearance or look more like P. franciscana, and that certain leaf traits show significant variation among the parental species and hybrids. Our genetic data show that hybrids share alleles with both parental species and suggest that hybridization may be more widespread than the single population at Snowslide Spring. Correlations between the morphology and genetics of these groups may be useful in providing managers with a tool for identifying hybrids without the expense of genetic analysis.