The Large Carpenter Bees (Xylocopa, Apidae) of the Neotropical Region: Phylogenetics, Classification and Biogeography

The large carpenter bees of the genus Xylocopa comprise almost 400 species distributed worldwide. Their large body and ability to build nests through woodworking make them one of the most remarkable groups of bees. In the Neotropics, they comprise over 100 species occurring in tropical and subtropical environments including islands in the Antilles and the Pacific. We provide a comprehensive phylogeny for the Neotropical lineage of Xylocopa to elucidate their biogeographic history and support their taxonomy and classification. Our phylogeny confirms the monophyly of the Neotropical lineage and their sister relationship with the Palearctic X . ( Proxylocopa ) and Oriental X . ( Nyctomelitta ), from which they diverged in the Oligocene. This implies a dispersal event to the Neotropics from Asia possibly through the Beringia. We recognise three main lineages within the Neotropical clade: Notoxylocopa, Neoxylocopa and Schonnherria. In South America, the lineage Neoxylocopa diversified mainly in the Amazon region, whereas Schonnherria diversification occurred in subtropical regions and mountains of eastern South America. Dispersal to islands occurred several times throughout the evolution of the Neotropical lineage, certainly facilitated by the behaviour of nesting in tree trunks found within the Schonnherria and Neoxylocopa lineages. All neotropical subgenera were recovered as monophyletic. We reinforce that X. ( Megaxylocopa ) and X. ( Neoxylocopa ) should be kept separated, as they were reciprocally monophyletic in our results, despite previous doubt about the recognition of X. ( Megaxylocopa ). In summary, our results provide unequivocal support for all Neotropical subgenera proposed in Hurd and Moure's revision, thus seeing no reasons to change their classification system.