Mounted specimen on display at the American Museum of Natural History, NYC.
When: Late Permian (~252 million years ago)
What: Scutosaurus is an extinct reptile. It lived during the end of the Permian, and was one of the giants of its time. It reached lengths of over 8 feet (~2.5 meters) and was massively built. This bulky form was a plant eater, and in a way was the cow of its time. Scutosaurus lived in what is now Russia, and during the Permian this land was a semi-arid expanse. Thus, it is thought the herbivorous Scutosaurus would have had to have a large range in order to find enough food to support its huge body. Its flattened teeth imply it was able to grind up branches and other plant material that was not exactly the most nutritious of options. Scutosaurus was most likely a slow moving form, protected by its large size and the many osteoderms that covered its skin.
Scutosaurus is not closely related to any living reptile. It is an anapsid reptile, which is a grade of stem taxa that fall outside of the modern clade of reptiles (turtles, crocodiles, lizards, and birds). At one point it was thought turtles fell into this variety of stem reptiles, but more and more evidence is placing them closer to other living reptiles. Scutosaurus, like most of its kin, went extinct in the massive end Permian extinction event. As the fauna rebounded in the Triassic, the niche of large plant eaters was filled with basal synapsids at first, but by the end of the Triassic massive plant eating dinosaurs started to appear and quickly dominated.