FIG. 1.

Salient features of the maximum likelihood estimate of relationships among 16S rRNA sequences from free-living and endosymbiotic bacteria. Nodes having posterior probabilities (PP) ≥95% and/or bootstrap support (BS) ≥80% are denoted with asterisks (PP/BS). Free-living bacteria lineages are not named. Endosymbiont clades of the Phenacoccinae are collapsed and in black; the bacterial groups Tremblaya phenacola and Brownia rhizoecola are designated in this paper. Endosymbiont lineages of other insect groups are in gray.