Addition of wsp sequences to the Wolbachia phylogenetic tree and stabilityof the classification

Wolbachia are symbiotic bacteria altering reproductive characters of numero us arthropods. Their most recent phylogeny and classification are based on sequences of the wsp gene. We sequenced wsp gene from six Wolbachia strains infecting six Trichogramma species that live as egg parasitoids on many in sects. This allows us to test the effect of the addition of sequences on th e Wolbachia phylogeny and to check the classification of Wolbachia infectin g Trichogramma. The six Wolbachia studied are classified in the B supergrou p. They confirm the monophyletic structure of the B Wolbachia in Trichogram ma but introduce small differences in the Wolbachia classification. Modific ations include the definition of a new group, Sem, for Wolbachia of T. semb lidis and the merging of the two closely related groups, Sib and Kay. Speci fic primers were determined and tested for the Sem group.