none The tolerance and utilization of ethanol, acetic acid and acetaldehyde vapour was investigated in Asobara persimilis (Hymenoptera: Braconidae), a parasitoid of Drosophila. No significant utilization of ethanol or acetaldehyde occurred at low concentrations ( lt 1.5% and 0.1% respectively), however both female and male longevity was increased at concentrations of 1.0 and 1.5% acetic acid. All substances were toxic at higher concentrations, but there was sexual dimorphism in that females survived significantly longer than males.