Bacteria of the genus Wolbachia (Rickettsiae) are widespread in arthropods
and can induce cytoplasmic incompatibility (CI), thelytoky (T) or feminizat
ion (F) in their host. Recent research on the wsp gene of mainly CI inducin
g Wolbachia has shown that this gene evolves at a much faster rate than pre
viously sequenced genes such as 16S or ftsZ. As a result this gene appears
to be very useful in subdividing the Wolbachia and twelve groups have been
distinguished to date. Here we extend the Wolbachia wsp data set with fifte
en T-Wolbachia, one F-Wolbachia and three other Cl-Wolbachia strains. The r
esults showed: (i) the addition of seven groups; (ii) no relation between h
ost phenotype and Wolbachia phylogenetic position; and (iii) possible horiz
ontal Wolbachia transfer between the moth Ephestia kuehniella and its paras
itoid Trichogramma spp.