Seven remarkable new fossil species of parasitoid wasps (Hymenoptera, Ichneumonidae) from the Eocene Messel Pit

A groundbreaking study reveals seven new fossil species of parasitoid wasps from the Eocene Messel Pit, Germany (~47 million years ago), significantly expanding our understanding of ichneumonid diversity and evolution. Among the discoveries, Scambus fossilobus is identified as the oldest unequivocal representative of the subfamily Pimplinae, with distinctive lobed claws providing a clear synapomorphy. Additionally, Labeninae (Trigonator macrocheirus) is documented outside Gondwana for the first time, challenging prior geographical assumptions about this group. The study also establishes minimum ages for genera like Rhyssella and Xanthopimpla, dating them back to the Early/Middle Eocene. However, two species remain taxonomically unresolved due to high homoplasy in ichneumonid traits, highlighting the need for rigorous taxonomic approaches. This research leverages exceptional fossil preservation at Messel Pit to refine phylogenetic placements and age estimates, offering new insights into the evolutionary history of parasitoid wasps.

Spasojevic, T., Wedmann, S., & Klopfstein, S. (2018). Seven remarkable new fossil species of parasitoid wasps (Hymenoptera, Ichneumonidae) from the Eocene Messel Pit. Plos One, 13(6), e0197477. https://doi.org/10.1371/journal.pone.0197477