3D pdf of the surface rendered model of Conostigmus sp. nov. (Hymenoptera: Ceraphronoidea) from the Baltic amber. MikoIstvan 2018 This file is a supplementary illustration for a manuscript submitted to PeerJ about a new insect species (Hymenoptera: Ceraphronoidea: <i>Conostigmus</i>) found in Baltic amber. <div><br></div><div>Ceraphronoids are some of the most commonly collected hymenopterans, yet they remain rare in the fossil record. <i>Conostigmus</i> sp. nov. from Baltic amber represents an intermediate form between the type genus, <i>Megaspilus</i>, and one of the most species-rich megaspilid genera, <i>Conostigmus</i>, supporting the hypothesis that <i>Megaspilus</i> is nested within <i>Conostigmus</i>. 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 <i>Dendrocerus dubitatus</i> Brues 1937, Stigmaphronidae, and Radiophronidae from Ceraphronoidea and consider them as <i>incertae sedis</i>. We also provide some guidance for their future classification.<br></div><div><br></div><div>The two specimens for the study were obtained from the private collection of Baltic amber inclusions of Christel and Hans Werner Hoffeins (Hamburg, Germany). Specimens are embedded in Polyester resin (Voss-Chemie, Uetersen) and are deposited in the Deutsches Entomologisches Institut (Müncheberg, Germany). </div>