An Updated Infrageneric Classification of the North American Oaks (Quercus Subgenus Quercus): Review of the Contribution of Phylogenomic Data to Biogeography and Species Diversity

The oak flora of North America north Mexico is both phylogenetically diverse and species-rich, including 92 species placed in five sections subgenus Quercus, the clade centered on Americas. Despite phylogenetic taxonomic progress genus over past 45 years, classification at subsectional level remains unchanged since early treatments by WL Trelease, AA Camus, CH Muller. In recent work, we used a RAD-seq based phylogeny 250 sampled from throughout Americas Eurasia to reconstruct timing biogeography American radiation. This work demonstrates that comprises mostly regional radiations with limited affinities Mexican clades, two sister group connections Eurasia. Using this framework, describe patterns diversity within formally classify 62 into nine major subsections Lobatae (the red oaks) Quercus white oaks), largest Quercus. We also distill emerging evolutionary biogeographic impact phylogenomic data systematics multiple complexes instances hybridization.