Around the world in 10 million years: rapid dispersal of a kleptoparasitoid spider wasp (Pompilidae: Ceropales)

Aim: Our aim was to estimate the historical biogeography of the kleptoparasitoid genus Ceropales and to determine the processes leading to its current worldwide distribution. We tested hypotheses of dispersal and vicariance scenarios underlying its widespread distribution.

Location: Worldwide.

Methods: Data from two nuclear markers (the D2–D3 regions of the 28S ribosomal RNA and long-wavelength rhodopsin) and one mitochondrial marker (cytochrome c oxidase I) for 52 specimens of Ceropales were used to reconstruct a dated phylogeny based on Bayesian inference. Two calibration points were used from previous analyses including all pompilids under a lognormal relaxed molecular clock to estimate lineage divergence times. We compared the fit of 12 biogeographical models, modifying the base BioGeoBEARS models to include a dispersal adjacency matrix. Base BioGeoBEARS models allow different cladogenetic processes: DEC (subset sympatry, narrow vicariance), DIVALIKE (narrow and wide vicariance), BAYAREALIKE (widespread sympatry), and +J versions of these that allow jump dispersal. Using the model with the best AIC score, we performed Biogeographic Stochastic Mapping (BSM) in order to infer biogeographic processes. We simulated 200 BSM using the DEC+J model and the consensus tree for the BEAST analysis.

Results: The origin of crown-group Ceropales was in the early Miocene, ca. 10.6 Ma (15.7–6.5 95% HPD), and eight dispersal events explain its widespread distribution. A constrained model, where only adjacent areas were allowed for dispersal had the highest likelihood under DEC+J model.

Main Conclusions: The widespread distribution of Ceropales can be explained by eleven jump-dispersal events that took place in a period of ca. 10 million years. Two separate dispersals at different times happened from the Eurasia to the Nearctic. These probably occurred across the Bering land bridge in the late Miocene and Pliocene. Dispersal from North and Mesoamerica to South America took place four independent times from the late Miocene to close to present time. Dispersal to the Ethiopian region from Eurasia occurred in the late Miocene and Pliocene. Dispersal back to Eurasia from the Ethiopian region took place three times independently in the Pliocene to close to present time. Dispersal to the Australian region took place from the late Miocene to the Pleistocene.