Fig. 1.

—Ixodes-borne Rickettsia spp. form a monophyletic clade within the traditional spotted fever group rickettsiae. Phylogenetic placement of the Ixodes-borne rickettsiae used in this study (red box) was inferred using maximum likelihood (n = 181 single copy orthologs; see text for details). Support values are based on 1,000 pseudoreplications. Strain-level variation is not described for monophyletic species; these branches are labeled in purple. Torix and Megaira group representatives (gray labels) have been shown to be basal to the Rickettsia (Schrallhammer et al. 2013; Pilgrim et al. 2017) and were used to root the tree. See supplementary table S1, Supplementary Material online, for relevant information identifying the genomes and loci used in this reconstruction.