Figure 1.

Phylogenetic tree of the SOPE and Wolbachia based on sequences of 16S rDNA genes. The other rDNA sequences were searched at the National Center for Biotechnology Information by using the blast network service. Alignments were performed and the phylogenetic tree was created as in ref. 14. Bacillus subtilis, a Gram-positive bacterium, was used as the out-group. The name of the bacteria or the host insect species is followed by the GenBank accession number. Scale bar, 0.1 substitution per site. *According to the classification of Werren et al. (23).