Euoplocephalus tutus and the Diversity of Ankylosaurid Dinosaurs in the Late Cretaceous of Alberta, Canada, and Montana, USA

A comprehensive review of ankylosaurid dinosaurs from the Late Cretaceous of Alberta, Canada, and Montana, USA, challenges long-standing taxonomic classifications. The study resurrects four species—Anodontosaurus lambei, Scolosaurus cutleri, Dyoplosaurus acutosquameus, and Oohkotokia horneri—as distinct from Euoplocephalus tutus, based on morphological differences in skull ornamentation, osteoderms, and skeletal features. Anodontosaurus is characterized by posterior orbital ornamentation and wide knob osteoderms, while Scolosaurus exhibits long squamosal horns and low medial osteoderms. Dyoplosaurus is differentiated by pelvic and pedal morphology, along with a narrow tail club knob. The research leverages extensive fossil material, including dozens of Euoplocephalus specimens, to refine our understanding of intraspecific variation and taxonomic diversity within this group.

Arbour, V. M., & Currie, P. J. (2013). Euoplocephalus tutus and the Diversity of Ankylosaurid Dinosaurs in the Late Cretaceous of Alberta, Canada, and Montana, USA. PLoS ONE, 8(5), e62421. https://doi.org/10.1371/journal.pone.0062421