A new megaspilid wasp from Eocene Baltic amber (Hymenoptera: Ceraphronoidea), with notes on two non-ceraphronoid families: Radiophronidae and Stigmaphronidae
István Mikó,
Thomas van de Kamp,
Carolyn Trietsch,
Jonah M. Ulmer,
Marcus Zuber,
Tilo Baumbach,
Andrew R. Deans
Affiliations
István Mikó
Frost Entomological Museum, Department of Entomology, Pennsylvania State University, University Park, PA, United States of America
Thomas van de Kamp
Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
Carolyn Trietsch
Frost Entomological Museum, Department of Entomology, Pennsylvania State University, University Park, PA, United States of America
Jonah M. Ulmer
Frost Entomological Museum, Department of Entomology, Pennsylvania State University, University Park, PA, United States of America
Marcus Zuber
Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
Tilo Baumbach
Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
Andrew R. Deans
Frost Entomological Museum, Department of Entomology, Pennsylvania State University, University Park, PA, United States of America
Ceraphronoids are some of the most commonly collected hymenopterans, yet they remain rare in the fossil record. Conostigmus talamasi Mikó and Trietsch, sp. nov. from Baltic amber represents an intermediate form between the type genus, Megaspilus, and one of the most species-rich megaspilid genera, Conostigmus. We describe the new species using 3D data collected with synchrotron-based micro-CT equipment. This non-invasive technique allows for quick data collection in unusually high resolution, revealing morphological traits that are otherwise obscured by the amber. In describing this new species, we revise the diagnostic characters for Ceraphronoidea and discuss possible reasons why minute wasps with a pterostigma are often misidentified as ceraphronoids. Based on the lack of ceraphronoid characteristics, we remove Dendrocerus dubitatus Brues, 1937, Stigmaphronidae, and Radiophronidae from Ceraphronoidea and consider them as incertae sedis. We also provide some guidance for their future classification.
