Dinosaur ancestor tooth on scute
Very nice Postosuchus tooth embedded on a scute of a Desmatosuchus. Postosuchus was one of the largest carnivorous reptiles during the late Triassic. It was a member of the family of the archosaurs, the ancestors of modern crocodilians as well as the lineage that includes non-avian dinosaurs. Postosuchus lived in what is now North America during the Late Triassic. Where Postosuchus was a closer relative to crocodilians, he had very short forelimbs relative to the hind limbs, which suggest that he may have been committed to bipedal locomotion like later bipedal dinosaurs. The Desmatosuchus was a large quadrupedal reptile up to 4.5 m long of the family of the Aetosaur. It had very large shoulder spikes and several rows of scutes and was a herbivore. Desmatosuchus was predated by Postosuchus. Very interesting combination of fossils.
Postosuchus kirkpatricki (tooth) - Desmatosuchus spurensis (scute)
Upper Triassic (227 208 mil y)
Chinle Formation, North Arizona, USA
Tooth 23 mm - 0.9" ; Scute 140 x 80 mm - 5.5" x 3.2"