For example, among the putative species of the Africa/Middle East/Asia Minor clade which contains the most invasive species the Ms, Q and ASL groups Arsenophonus appears well established, whereas the invasive B group has been shown to be uninfected, despite extensive symbiont screening

[28, 34, 39]. The prevalence varies considerably within and among GDC-973 populations and genetic groups infected by Arsenophonus. For example, Q is composed of three COI-differentiated groups, Q1, Q2 and Q3 [28]. To date, these three cytotypes have not shown the same geographical distribution and show different endosymbiotic bacterial community compositions [28, 40]. The subgroup Q1, found in Europe, is not infected by Arsenophonus but harbors three other bacteria [28]. In contrast, Q2 observed in the Middle East and Q3 reported only in Africa show high prevalence of Arsenophonus in co-infection with Rickettsia [28, 34, 41]. Ms individuals are highly infected by Arsenophonus with a high level of co-infection by Cardinium [37]. All of these groups (B, Q, ASL, Ms and AnSL) show quite different geographical ranges. Ms has been detected on the islands in the southwestern part of the Indian Ocean, Tanzania and Uganda, living in sympatry with B [42]. ASL and AnSL have been reported only in Africa [28, 35, 43–46]. In contrast, the invasive B and Q groups are spread all over the world. Q has been found in Africa,

America, Europe, Asia and the PI3K inhibitor review Middle East [28, 34, 47, 48]. However, this situation is constantly in flux, because commercial trade is responsible for recurrent introduction/invasion processes of B. tabaci giving rise to new sympatric situations. Moreover, potential horizontal CHIR-99021 datasheet transfers of symbionts and interbreeding can generate new nucleo-cytoplasmic HSP90 combinations and thus rapid evolution of symbiont diversity. Patterns of Arsenophonus infection in B. tabaci within the high-level Africa/Middle East/Asia Minor groups make this clade a good candidate to study,

on fine taxonomic and time scales, the spread of this bacterium, its ability to be horizontally transferred and finally, its evolutionary history, including genetic diversity generated by recombination events. In the present paper, we explore the prevalence and diversity of Arsenophonus strains in this clade using an MLST approach to avoid the disadvantages of the rRNA approach. In parallel we also studied, as an outgroup, the Sub-Saharan AnSL species (S biotype), considered the basal group of this species complex, and two other whitefly species found at the sampling sites, Trialeurodes vaporariorum and Bemisia afer. Methods Insect sampling Individuals from different species of Bemisia tabaci and two other Aleyrodidae species were collected from 2001 to 2010 from various locations and host plants in Africa and Europe and stored in 96% ethanol (Table 1, Figure 1). Table 1 Sampling locations of Aleyrodidae used in this study, B.