Fig. 2: Phylogenetic tree showing the relationship of candidate horizontally transferred Wolbachia segments in the T. rathkei genome to other Wolbachia isolates.

The T. rathkei Wolbachia insertion (indicated by the asterisk) is closely related to Wolbachia isolates from other isopods, and its closest relative is the wCon from Cylisticus convexus. Numbers by nodes indicate bootstrap support. Branch lengths represent the average number of substitutions per site. The tree was generated by concatenating all candidate Wolbachia insertions in T. rathkei longer than 1000 bp, along with the best-matching regions in the reference Wolbachia genomes (found with BLAST), aligning with MUSCLE v.3.8.31 (Edgar 2004), filtering alignments with trimal v. 1.2rev59 (Capella-Gutiérrez et al. 2009), selecting a model using ModelTest-NG v. 0.1.6 (Darriba et al. 2020), and running the analysis in RAxML-NG v. 0.9.0 (Stamatakis 2014) with 100 bootstrap replicates.