Fig. 5 in A new tyrannosaurine (Theropoda:Tyrannosauridae) from the Campanian Foremost Formation of Alberta, Canada, provides insight into the evolution and biogeography of tyrannosaurids

Fig. 5. Left maxilla of referred specimen of Thanatotheristes (TMP 2018.16.1) in lateral view. Note the presence of pronounced vertical ridges (arrows) on subcutaneous surface, an autapomorphy of the taxon. Abbreviations: dvr, dorsoventral ridges; sc-afos, subcutaneous-antorbital fossa boundary. Scale bar equals 5 cm.