Although tachinids parasitize a wide variety of insects, vespid wasps are not commonly recorded as hosts. Three lineages of Tachinidae are parasitoids of larvae of eusocial Vespidae, namely the Old World tribe Anacamptomyiini and some Neotropical species of the Blondeliini genera Ophirion Townsend and Lixophaga Townsend. The taxonomy of anacamptomyiine species has been improved and clarified in the last decades, but Neotropical species of Ophirion and Lixophaga are still difficult to identify, preventing further studies in the group. I present here an annotated catalog of vespid hosts of Tachinidae, with an overview of host use and oviposition strategies of their parasitoid species. Moreover, I describe a new host record for O. lenkoi sp. nov. Gudin and L. punctata (Townsend), reared from a nest of Polybia (Myrapetra) scutellaris (White) in Nova Europa, São Paulo, Brazil. Ophirion lenkoi sp. nov. is described and L. punctata is redescribed, with two new junior synonyms proposed: L. fitzgeraldi (Curran), syn. nov., and L. dubiosa (Thompson), syn. nov. I also include illustrations of type material and discuss the most relevant diagnostic characters for species of both genera. Lastly, I argue that the biology of Lixophaga species may be a suitable model to understand how tachinids were able to explore eusocial vespid hosts.
Parasitoid flies, Oviposition strategy, Meconium, Eusociality, New synonym.
