Supplementary Figure S1 Phylogenetic tree representing species of the wasp genus Psenulus (Kohl, 1897). Bayesian analysis was based on cox1 sequences (201 polymorphic nucleotides out of 637 sites), including 37 Psenulus and five outgroup specimens [Diodontus minutus (Fabricius, 1793) and Pemphredon lethifer (Shuckard, 1837)]. The analysis was performed with the substitution model GTR+G, estimated with jModelTest 0.1.1, and run in two chains with 5 million generations each. After discarding the burn-in, 37,501 trees were sampled of a total of 100,002 trees from both chain files. Bifurcations with posterior probabilities of <0.9 were collapsed, except for branches with ambiguous Maximum Likelihood and Bayesian results (thick grey bifurcations). All thick black branches represent posterior probabilities of at least 0.99. Specimens are labelled with the specimen ID, the GenBank accession number or the Barcode Index Number BIN of the BOLD System.