Gastonia

Phylogeny: Dinosauria > Ornithischia > Genasauria > Thyreophora > Thyreophoroidea > Eurypoda > Ankylosauria > Euankylosauria > Nodosauridae > Polacanthinae

Overview: Fossilized remains of this tank-like animal have been found within the Cedar Mountain Formation of Utah, specifically within its deeper layers. Gastonia probably lived about one hundred and thirty-five million years ago, in a semi-arid floodplain dotted by lakes and sparse woodlands. It mainly fed upon ground-level plants, which were more available during the rainy season, when the rivers and streams were swelled by monsoons. Gastonia is known to have coexisted with a number of other dinosaurs such as the brachiosaurid Cedarosaurus, the turiasaur genus Moabosaurus, the ornithopods Iguanacolossus and Hippodraco, basal therizinosaurs like Falcarius, and the enormous dromaeosaurid Utahraptor – the largest of the “raptor” dinosaurs. Utahraptor was probably one of the region’s top predators, and the main threat to Gastonia, at least as a juvenile. Ankylosaurs are often seen as solitary animals, but Gastonia appears to have lived in small groups.

Gastonia was fairly well protected from predators. Like all ankylosaurs, most of its body sported a large number of bony scutes, growing in rows and taking on different forms. Some were small, but others were enormous, shaped like flattened spines. These spinier osteoderms mainly grow on the shoulders, upper back and along the sides of the animal’s tail. Gastonia, if threatened, may’ve been able to ram into its attacker. It was a decently large ankylosaur, with an estimated length of maybe five or so meters, with a fairly bulky body. Gastonia lacked a tail club, which is typical for a member of the ankylosaur family Nodosauridae. Nodosaurids are traditionally split into a few major groups or subfamilies, one of these being the subfamily Polacanthinae. Some studies classify Gastonia as a polacanthine, close to the English nodosaurid Polacanthus. Described in 1998, the genus is named for the entrepreneur and fossil hunter Robert Gaston, who discovered the fossil site where Gastonia would later be found.