Sequencing data were deposited in NCBI GenBank under the BioProject PRJNA501864. The genomes of 'Candidatus Finniella inopinata', endosymbiont of Peranema trichophorum strain CCAP 1260/1B and endosymbiont of Stachyamoeba lipophora strain ATCC 50324 were deposited in NCBI GenBank under the accessions GCA_004210305.1, GCA_004210275.1 and GCA_003932735.1. Raw sequencing reads were deposited on the NCBI SRA archive under the accessions SRR8145469, SRR8145470, SRR8156519, SRR8156520, SRR8156521, SRR8156522. Multi-gene datasets as well as phylogenetic trees inferred in this study were deposited at Mendeley Data under the DOI: http://dx.doi.org/10.17632/75m68dxd83.2
NCBI BioProjectID PRJNA501864. Sequence data from: An updated phylogeny of the Alphaproteobacteria reveals that the parasitic Rickettsiales and Holosporales have independent origins.