Andean Origin and Diversification of the Genus Perezia, an Ancient Lineage of Asteraceae

Perezia is an Andean-centered genus and belongs to the early diverging lineages in the phylogenetic tree of the Asteraceae (Compositae). Previous studies in Perezia proposed several evolutionary lines and alternative areas of origin. A phylogenetic morphological analysis was performed to test these hypotheses and ancestral areas and dispersal-vicariance analyses were applied. The results of the phylogenetic analysis support Perezia as a monophyletic taxon, including the recently excluded Perezia nutans and P. prenanthoides, and support most of the previously proposed evolutionary lines. The biogeographic results suggest the southern Andes as the probable ancestral area for Perezia, with multiple dispersals. Supported by geologic, paleoclimatology, and fossil evidence, it is inferred that the ancestor of Perezia may have inhabited the areas above the humid, temperate forests in the southern Andes during the Tertiary.