A new, transitional centrosaurine ceratopsid from the Upper Cretaceous Two Medicine Formation of Montana and the evolution of the 'Styracosaurus-line' dinosaurs.

ABSTRACT: Ceratopsids are among the most ubiquitous dinosaur taxa from the Late Cretaceous terrestrial formations of the Western Interior of North America, comprising two subfamilies, Chasmosaurinae and Centrosaurinae. The Two Medicine Formation of northwestern Montana has produced numerous remains of centrosaurine dinosaurs, which represent three taxa previously considered valid: Rubeosaurus ovatus, Einiosaurus procurvicornis and Achelousaurus horneri. Here, we reassess the previous referral of specimens to Rubeousaurus ovatus and demonstrate that this taxon is represented solely by its holotype specimen, which was first diagnosed as Styracosaurus ovatus. One of the specimens previously referred to 'Rubeosaurus' ovatus instead represents a new eucent

SUBMITTER: Wilson JP 

PROVIDER: S-EPMC7211873 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature