The aim of this project is an external and internal morphological study of key amber beetle fossils by direct observation (for external morphology) and virtual dissection (for internal structures) using propagation phase contrast synchrotron X-ray microtomography. Critical data obtained from fossils by these methods will be integrated into the interdisciplinary investigation of the biggest animal evolutionary radiation, the phylogeny of Coleoptera Staphylinoidea. This is a continuation of EC530 and LS 2248.