Redescription of the Cretaceous species Archaeocerus uenoi Perreau, 2019 based on synchrotron radiation micro-tomography and nano-tomography (Coleoptera, Leiodidae, Catopocerinae)

The only known extinct species of the subfamily Catopocerinae (Leiodidae), Archaeocerus uenoi Perreau, 2019, is redescribed. The female is described for the first time and the internal morphology (genitalia) of both sexes is described and illustrated using X-ray synchrotron micro-tomography and nano-tomography. These new observations allow a detailed description of the aedeagus, ensuring a complementary comparison with extant genera and confirming the placement of the genus Archaeocerus in the subfamily Catopocerinae.