, Volume 57, Issue 4, pp 493-502

Open Access This content is freely available online to anyone, anywhere at any time.

Phoresy in the field: natural occurrence of Trichogramma egg parasitoids on butterflies and moths

  • Nina E. FatourosAffiliated withLaboratory of Entomology, Wageningen University Email author 
  • , Martinus E. HuigensAffiliated withLaboratory of Entomology, Wageningen University


Phoretic insects utilize other animals to disperse to new environments. We recently discovered how egg parasitoids use an exciting phoretic strategy to reach egg-laying sites of their butterfly hosts. In the laboratory, female Trichogramma wasps detect and mount mated female cabbage white butterflies that emit an anti-aphrodisiac pheromone. Hardly any information exists about the natural occurrence of phoresy in wasps of this genus. Therefore, we monitored the presence of phoretic Trichogramma wasps on lepidopteran hosts in the field. Only female wasps were found at low prevalence on six lepidopteran species. Wasps were mostly found on female hosts and mainly on abundant solitary host species. This is the first report of phoretic Trichogramma wasps on butterflies in nature. We suggest that phoresy is only one of several strategies used by these polyphagous egg parasitoids. The evolution of phoresy is discussed in relation to the nutritional ecology of egg parasitoids.


Hitchhiking Anti-aphrodisiac Oviposition-induced plant cues Lepidoptera Gregarious Solitary