Thirty-six unique strains are shown. Sample code (Additional file 1) and

host species name in which each strain was detected are indicated (for abbreviations see legend Figure 2). ML bootstrap values (top number, bold) and Bayesian posterior probabilities (bottom number, plain) are depicted (only values larger than 50 are indicated). * = the topology within this clade is slightly different for the MrBayes topology. The bar at the bottom indicates a branch length of 10% likelihood distance. Independent phylogenies for each gene are depicted in Additional file 3. Figure 5 16S rDNA, gyrB , and concatenated ML phylogenies find more for Cardinium. Sample code (Additional file 1) and host species name in which each strain was detected are indicated: BR=B. rubrioculus; BS=B. sarothamni; PH= P. harti. Two clades are named I and II. ML bootstrap values (top LY2835219 number, bold) and Bayesian posterior probabilities (bottom number, plain) are depicted (only values larger than 50 are indicated). The bar at the bottom indicates a branch length of 10% likelihood distance. Multiple infections Evofosfamide Wolbachia and Cardinium were found co-infecting B. rubrioculus, B. sarothamni, and T. urticae. In B. rubrioculus and B. sarothamni, Wolbachia and Cardinium

strains were obtained from doubly infected individuals, whereas in T. urticae they were obtained from singly infected individuals (Additional file 1). Multiple Wolbachia strains infecting a single host individual were not detected, and neither were multiple Cardinium strains. Sequence chromatograms revealed no double peaks and cloning and sequencing of eleven PCR products did not reveal multiple infections. Wolbachia diversity Sequences from the four Wolbachia genes (wsp, ftsZ, groEL, Fenbendazole and trmD) were recovered for 65 Wolbachia infected individuals, except for

wsp from B. spec. V (ITA11). The Wolbachia strain infecting B. spec. V belongs to the newly described supergroup K [12], which is highly divergent from supergroup B strains infecting other tetranychid mites. We excluded the supergroup K strain from phylogenetic and recombination analyses. No insertions or deletions were found within ftsZ, groEL, and trmD. Within wsp small indels (3-9bp) were found in a few strains but all sequences could be unambiguously aligned. The sequenced Wolbachia strains reveal a high diversity. From the 64 Wolbachia strains (excluding the supergroup K Wolbachia strain in B. spec. V), 36 strains (sequence types; STs) were found unique (Additional file 2). Between 11 (groEL) and 18 (trmD) alleles were found per locus (Table 1). Nucleotide diversity was 5-11 times higher for wsp than for the other loci (Table 1). The dN/dS ratio was < 1 for all loci, indicating that the genes where not subjected to positive selection. The wsp gene also revealed a high rate of intragenic recombination (see below), with two sites identified within hyper variable region 1 (HVR1) under positive selection (HyPhy: codons 20 and 30; unpublished data).