No evidence for Wolbachia-induced parthenogenesis in the social Hymenoptera

In some parasitoid wasps, infection by the micro-organism Wolbachia leads t o asexual reproduction. Within the Hymenoptera, the limits of distribution of parthenogenesis inducing Wolbachia have not yet been established. To add ress this issue, we screened all known thelytokous social hymenopteran spec ies using a PCR assay. None was infected, and therefore we conclude that wo rker thelytoky evolves independently of Wolbachia in ants and bees. This su pports the previously proposed hypothesis that a sex determining system bas ed on heterozygosity may form a proximate limitation to Wolbachia-induced p arthenogenesis.