A genus of about 85 species, perennials, mostly of north temperate, boreal, and arctic regions of North America, South America, and Eurasia. As shown by molecular data, Saxifraga, as often broadly defined, is polyphyletic, and all of our native species belong in Micranthes (Soltis 1995, Soltis et al. 1996, Mort & Soltis 1999, Tkach et al. 2015). Soltis et al. (1996) demonstrate that Micranthes is closely allied with Heuchera, Mitella, and Tiarella, less closely related to Astilbe, Boykinia, Sullivantia, and Chrysosplenium, and least closely related to the bulk of Saxifraga. Sectional classification follows Tkach et al. (2015).
Ref: Brouillet & Elvander (2009a) In Flora of North America Editorial Committee (2009); Brouillet & Gornall (2007); Cushman, Richards, & McMillan (2020); Lanning (2009); Lanning & Mathews (2019); Mort & Soltis (1999); Soltis et al. (1996); Soltis In Kubitzki, Bayer, & Stevens (2007); Tkach, Röser, & Hoffmann (2015). Show full citations.