Fig. 9. 3D in The First Reconstruction of the Head Anatomy of a Cretaceous Insect, †Gerontoformica gracilis (Hymenoptera: Formicidae), and the Early Evolution of

Fig. 9. 3D reconstructions of the heads of †Gerontoformica gracilis (on the left) and crown Formicidae (on the right) illustrating character transitions at the root of crown Formicidae, i.e., excluding †Gerontoformica. The relevant characters and states are marked with cyan outlines for plesiomorphies and magenta outlines for apomorphies; where applicable, physical directions of state changes are marked by arrows of the same colors. Complete illustrations of character states in all investigated taxa can be found in the character list at the end of this contribution. Char. 7: Ventral view on the head of †G. gracilis and Brachyponera luteipes, showing a medium versus a long postgenal bridge.Char. 36: Dorsal view on the posterior portion of the head of †G. gracilis and Brachyponera luteipes, showing presence versus absence of ocelli. Char. 42: Ventral view on the head of †G. gracilis and Brachyponera luteipes, showing a rounded versus projecting hypostomal tooth. Char. 46: Frontal view of the oral foramen of †G. gracilis and Brachyponera luteipes, showing a hypostomal corner situated far lateral of the tip of the hypostomal process versus a hypostomal corner aligned with the tip of the hypostomal triangular process. Char. 78: Frontal view of the scapus of †G. gracilis and Formica rufa showing a short scapus relative to the flagellum versus a long one. Only part of the antennal flagellum is shown, as this is not entirely imaged in the used µCT-scan data. Char. 86: Lateral view of the mandibular articulation of †G. gracilis and F. rufa showing the atala either broadly and flatly bulging or narrowly and highly bulging.Char. 94 and 97: Dorsal view of the mandible of †G. gracilis and F. rufa showing a narrow mandibular blade and gnathal edge without denticles proximad the subapical tooth versus a basally broadened mandibular blade with basal angle and denticles developed on the gnathal edge. Char. 108: Frontal section through the M. craniomandibularis internus (0md1) of †G. gracilis and F. rufa showing all fibers directly attaching to the main apodeme (magenta) versus some fibers attaching on thin cuticular fibrillae (cyan). Char. 143: Dorsal view of the prepharynx digestive tract of †G. gracilis and Wasmannia showing one bundle of the lateral portion of M. pharyngoepipharyngalis (0pe1l) versus two bundles.