Host specificity of the parasitoid, Sphecophaga vesparum (Curtis) (Hymenoptera: Ichneumonidae), a potential biological control agent of the social wasps, Vespula germanica (Fabricius) and V. vulgaris (Linnaeus) (Hymenoptera: Vespidae) in Australia

Choice, non‐choice, and host location tests using Sphecophaga vesparum indicated that brood of some Australian native Polistes, Ropalidia , and Trigona species would not be at risk from releases of the parasitoid in Australia. Capped brood of two species of Polistes , four species of Ropalidia , and the stingless bee, Trigona carbonaria , were screened. Only two cells of R. plebeiana and one of R. revolutionalis produced cocoons of S. vesparum. S. vesparum was approved for release in Australia and released in metropolitan Melbourne (Victoria) in December 1989.