Recent molecular phylogenetic analyses have revealed that Saxifraga sect. Trachyphyllum as currently circumscribed is polyphyletic, with the designated type, S. aspera, falling outside of the more speciose clade. Several other lines of morphological, geographic, and ecological evidence also distinguish the two distantly related groups from one another. In combination, these data necessitate the circumscription of a new section, S. sect. Bronchiales, which is described herein. The section is hypothesized to have arisen in the southern Rocky Mountains of North America, followed by northwestward expansion across Beringia and diversification among refugia.

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