accession number USNM 11869. Unlike S. albertensis, the longest parietal spikes converge towards their tips, instead of projecting parallel behind the frill. There also may only have been two sets of spikes on each side of the frill, instead of three. As estimated from the preserved material, the spikes are much shorter than in S. albertensis, with the longest only long. An additional specimen from the Two Medicine Formation was referred to Styracosaurus ovatus in 2010 by Andrew McDonald and John Horner, having been found earlier in 1986 but not described until that year. Known from a premaxilla, the nasal bones and their horncore, a postorbital bone and a parietal, the specimen Museum of the Rockies 492 was considered to share the medially-converging parietal spikes with the only other specimen of S. ovatus, the holotype. Following this additional material, the species was added to a phylogenetic analysis where it was found to group not with Styracosaurus albertensis, but in a clade including Pachyrhinosaurus, Einiosaurus and Achelousaurus, and therefore McDonald and Horner gave the species the new genus name Rubeosaurus. Another specimen, the partial immature skull USNM 14768, which was earlier referred to the undiagnostic genus Brachyceratops, was also referred to Rubeosaurus ovatus by McDonald and colleagues in 2011. While the medial spikes of USNM 14768 were too incomplete to show if it shared the convergence seen in other R. ovatus specimens, it was considered to be the same species as it was also found in the older deposits of the Two Medicine Formation, and had a unique combination of parietal features only shared completely with the other specimens of the species. Though it was originally found to nest closer to Einiosaurus and later centrosaurines by McDonald and colleagues in both 2010 and 2011, revisions of phylogenetic analyses in 2013 by Scott Sampson and colleagues, and further expansions and modifications of the same dataset, instead placed Rubeosaurus ovatus as the sister taxon of Styracosaurus albertensis, as had been originally considered when the species was first named, though the two species were not moved into the same genus as originally named. A review of the variability within known Styracosaurus specimens by Robert Holmes and colleagues in 2020 found that USNM 11869, the type specimen of Rubeosaurus ovatus, fell within the variation seen in other specimens from the older deposits of the Dinosaur Park Formation S. albertensis is known from. While no phylogenetic