Fig. 4

CT slices of the posterior superognathal of Leptodontichthys ziregensis gen. et sp. nov. (PIMUZ A/I 5022). a Overview in labial view. b–f, both tooth rows showing layers of dentin and the pulp cavities. b Parasagittal view of the posterior row and c of the lateral row. d, e, transverse sections (e: close-up). f Frontal section. g Growth development of Plourdosteus canadensis according to Ørvig (1980). h Posterior row and i lateral row. Both tooth rows of L. ziregensis gen. et sp. nov. were 3D reconstructed to show these layers and some preserved basal canals. Scale bars represent 10 mm (a–d, g), 2 mm (e), 4 mm (f) and 5 mm (h, i). LT, Lateral Tooth; PT, Posterior Tooth