page_title: Medusaceratops
section_title: Description
hierarchical_section_title: Medusaceratops / Description
caption_attribution_description: English: Medusaceratops
context_page_description: Medusaceratops is an extinct genus of centrosaurine ceratopsian dinosaur known from the Late Cretaceous Judith River Formation of Montana, northern United States. It contains a single species, Medusaceratops lokii.
context_section_description: Two partial parietals (frills) that are housed at the Wyoming Dinosaur Center were chosen as the type material of Medusaceratops, including the holotype WDC DJR 001 and the paratype WDC DJR 002. Although all the chasmosaurine material from the Mansfield Bonebed was thought to be referable to Medusaceratops, which totals at several hundred individual elements, upon its original description only these two partial frills have been scientifically described while the rest of the material was being reexamined. Many of the other elements are not diagnosable to a genus level and can only be confidently referable to Ceratopsidae.
  Upon its original description Medusaceratops was thought to represent a chasmosaurine. It was suggested that based on its type material alone, Medusaceratops is unique among Chasmosaurinae in having only three epiparietals (frill spikes) on each side of the frill. The first frill spike pair is large and the second is smaller, and both are uniquely widened at base, pachyostotic, curve down the sides of the frill, and are depressed down the front of the frill. The third frill spike pair is small and triangular, unmodified in comparison to early chasmosaurines, but similarly depressed, and borders the squamosal bone. The highly broadened and curved first frill spike pair of Medusaceratops closely resembles the third pair of the frill ornamentation of Albertaceratops, however Medusaceratops was thought to differ (like all chasmosaurines) in lacking tab-shaped, frequently overlapping fourth to seventh pairs of the frill ornamentation of centrosaurines.
  This was challenged in 2018, by the description of additional Mansfield Bonebed material assignable to Medusaceratops. It became apparent that the 1-3 frill spikes mentioned above are in fact spikes 2-4. The first epiparietal is small and variably procurving and thus was misinterpreted before. At least one more epiparietal pair was also identified (after the fourth), resulting in a total of at least 5 pairs, consistent with centrosaurines like Albertaceratops and Wendiceratops, but not with chasmosaurines. The midline ramus of Medusaceratops, a bone separating the two sides of the frill, was also among the newly described material. It is broad, resulting in rounder and smaller frill fenestrae (holes) like in other centrosaurines. Thus, the new study reassigned Medusaceratops to Centrosaurinae, among which it is most similar to Albertaceratops and Wendiceratops.
caption: Restoration
exif: {"Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS3 Windows", "Image DateTime": "2018:01:16 00:54:39", "Image ExifOffset": "164", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "302", "Thumbnail JPEGInterchangeFormatLength": "6036", "EXIF ColorSpace": "Uncalibrated", "EXIF ExifImageWidth": "572", "EXIF ExifImageLength": "423"}