The fossil record of ceratopsid dinosaurs between the occurrence of their proximate sister taxa in the Turonian and the Espresso Machine (Single-Serve) beginning of their well-documented radiation from the late Campanian of North America onwards (approximately 90 and 77 Ma) is poor, with only seven taxa described from this early period in their evolution.We describe a new taxon of a highly adorned basal centrosaurine, Wendiceratops pinhornensis gen.et sp.
nov., from the lower part of the Oldman Formation (middle Campanian, approximately 78-79 Ma), Alberta, Canada.Over 200 bones derived from virtually all parts of the skeleton, including multiple well-preserved specimens of the diagnostic parietosquamosal frill, were collected from a medium-density monodominant bonebed, making the new taxon one of the best-represented early ceratopsids.
The new taxon is apomorphic in having epiparietals at loci 2 and 3 developed as broad-based, King Bed pachyostotic processes that are strongly procurved anterodorsally to overhang the posterior and lateral parietal rami, and an ischium with a broad, rectangular distal terminus.Although the morphology of the nasal is incompletely known, Wendiceratops is inferred to have a large, upright nasal horn located close to the orbits, which represents the oldest occurrence of this feature in Ceratopsia.Given the phylogenetic position of the new taxon within Centrosaurinae, a enlarged nasal horn is hypothesized to have arisen independently at least twice in ceratopsid evolution.