Euoplocephalus tutus and the Diversity of Ankylosaurid Dinosaurs in the Late Cretaceous of Alberta, Canada, and Montana, USA
A) Distribution of ankylosaurid specimens within the Dinosaur Park Formation. Megaherbivore Assemblage Zones after Mallon et al. . Specimens marked with green stars have GPS coordinates and accurate elevation data, specimens marked with yellow dots have elevations estimated from field notes, and the location of TMP 1991.127.1 (marked by a blue hexagon) was estimated from Alberta Township System coordinates. The elevation of some specimens with GPS coordinates was also estimated using field notes and Google Earth; the vertical lines associated with these illustrate the maximum elevation from using field note data only. Specimens marked by yellow dots, as such, could vary in elevation anywhere from three to seventeen meters. ROM 784 is the holotype of Dyoplosaurus acutosquameus and NHMUK R5161 is the holotype of Scolosaurus cutleri. Although the exact locality and elevation for the holotype of Euoplocephalus tutus (CMN 0210) is unknown, AMNH 5406 and UALVP 31 can be confidently referred to that taxon. B) Stratigraphic column showing Upper Cretaceous formations in southern Alberta. Nomenclature for the Horseshoe Canyon Formation follows Eberth and Braman . CMN 8530, the holotype of Anodontosaurus lambei, occurs in the Horsethief Member.