The aim of this study was to record the parasitoid species found in social wasps nests sampled in different localities in Brazil and investigate the existence of preferential host-parasite associations in different tribes of Neotropical paper wasps. We sampled nests of Mischocyttarus cassununga, Mischocyttarus consimilis, Mischocyttarus imitator, Polistes canadensis, Polistes cinerascens, Polistes versicolor, Angiopolybia pallens, Leipomeles spilogastra, Polybia jurinei and two indeterminate species of Mischocyttarus. M. cassununga, M. imitator and Mischocyttarus (Phi) sp.1 were parasitized by Toechorychus guarapuavus (Ichneumonidae) and M. consimilis, M. imitator and Mischocyttarus sp. 2 was parasitized by Toechorychus fluminensis (Ichneumonidae). P. versicolor and P. cinerascens were parasitized by Elasmus polistes (Eulophidae) and P. canadensis by Simenota depressa (Trigonalidae); A. pallens and L. spilogastra, were infested by Brachymeria sp.1 and Brachymeria sp.2 (Chalcididae), respectively. M. cassununga and Polybia jurinei were parasitized by Megaselia scalaris (Phoridae). We suggested that there may be specific and preferential association between parasitoids and social paper wasps.
