†Megacoxa synchrotron gen. et sp. nov., holotype male CASENT0753237, mid-Cretaceous, Kachin amber (E–H: reconstructed using synchrotron radiation-based micro-computed tomography). A habitus in lateral view; B head and anterior mesosoma in lateral view; C metacoxa in lateral view; D habitus in dorsal view; E habitus in dorsal view; F mesosoma in dorsal view; G mesosoma in lateral view; H head in frontal view, with antennae numerically removed. Scale bars: 1 mm (A, D, E); 0.5 mm (B, F, G, H); 0.25 mm (C). Abbreviations: AG = inner axillar groove; Cx = hind coxa; MeS = mesometapectal sulcus; MMS = median mesoscutal sulcus; PpL = parapsidal line; sp = anterior thoracic spiracle.