Cretaceous West Gondwana vicariance shaped giant water scavenger beetle biogeography

Abstract

AbstractAimWe tested the hypothesis that ancient vicariance in giant water scavenger beetles shaped their current distribution.LocationWorldwide except Antarctica.MethodsWe inferred a molecular phylogenetic hypothesis for the tribe Hydrophilini using probabilistic methods based on broad geographical and taxonomic sampling. We used fossil‐based molecular dating and likelihood model‐based ancestral range estimation to reconstruct the biogeography of this clade.ResultsOur results suggest that the tribe originated in the Cretaceous about 120 Ma with a most likely ancestral range in the Gondwanan fragment comprising continental Africa and South America. We infer an ancient vicariance following this early origin, consistent with the split of these two large landmasses in the mid‐Cretaceous. The rest of the biogeographical history of the group is shaped by dispersal events throughout the Cenozoic.Main conclusionsThe biogeographical history of hydrophiline water beetles is consistent with the hypothesis of West Gondwana vicariance, although an origin in either Africa or South America is a likely alternative. Although the early cladogenesis of this clade might have been shaped by the opening of the Atlantic Ocean, subsequent biogeographical evolution is mainly driven by dispersal events.