Leaf-cutter bee damage on Lauraceae leaves from the middle Eocene Anglesea fossil site conflicts with current phylogenies for megachilids (Hymenoptera: Megachilidae) in Australia

Damage to the margin and surface of fossil leaves has been used to identify the likely insect groups involved and to track potential changes in insect communities through evolutionary time. The Anglesea fossil site in Victoria, Australia, has a rich array of fossil leaves preserved in clay and clay-sand through six fossil lenses dated at late middle Eocene, ~40 Ma. Examination of a large number of fossil leaves and comparison to Northern Hemisphere fossils and modern damage has resulted in 12 with unique margin excisions postulated to be caused by megachilid leaf-cutter bees. Such findings precede the current dated megachilid phylogeny by ~24 million years. This study aims to draw attention to this discrepancy which may have implications for the understanding of megachilid dispersal events into Australia.