Fig. 2

Relationships between molecular evolutionary rate, nucleotide composition, and genome size between gut symbiotic bacteria of pentatomid stinkbugs, gut symbiotic bacteria of other stinkbug groups, and allied free-living γ-proteobacteria. a K vs. AT content of 16S rRNA gene. b K vs. genome size. c AT content of 16S rRNA gene vs. genome size. K is defined as estimated genetic distance from the outgroup of “the stinkbug gut symbiont clade subjected to comparative evolutionary analyses” (see Fig. 1 and Additional file 5), reflecting the molecular evolutionary rate of the lineage