page_title: Pentaceratops
section_title: Discoveries and species
hierarchical_section_title: Pentaceratops / Discoveries and species
caption_attribution_description: English: Company C, 1st Battalion, 171st Aviation, UH-60 Black Hawk crew consisting of pilots Maj. Daniel Purcell and Capt. Kevin Doo, and crew chiefs Sgt. 1st Class Dennis Cahill and Sgt. Saul Monarez airlift a unique sling load of a baby Pentaceratops dinosaur skull out of the Bisti/De-na-zin Wilderness Area Oct. 29, 2015. Sgt. Bryan Haworth and Spc. Alonzo Romero, both of 1st Battalion 200th Infantry, hook the 4,500 pounds load onto the belly of the aircraft. The New Mexico Army National Guard conducted a civil-military community support project Oct. 28-29, assisting the New Mexico Museum of Natural History and Science in transporting 65 million-year-old Pentaceratops dinosaur fossils from the Bisti and Ah-Shi-Sle-pah Wilderness Areas to the museum in Albuquerque, N.M. (Released, Photo by Sgt. 1st Class Anna Doo, New Mexico National Guard Public Affairs)
context_page_description: Pentaceratops is a genus of herbivorous ceratopsid dinosaur from the late Cretaceous Period of what is now North America.
  Pentaceratops fossils were first discovered in 1921. The genus was named in 1923 when its type species Pentaceratops sternbergii was described. Pentaceratops lived around 76–73 million years ago, its remains having been mostly found in the Kirtland Formation in the San Juan Basin in New Mexico. About a dozen skulls and skeletons have been uncovered, so anatomical understanding of Pentaceratops is fairly complete. One exceptionally large specimen later became its own genus, Titanoceratops, due to its more derived morphology, similarities to Triceratops, and lack of unique characteristics shared with Pentaceratops.
  Pentaceratops was about 6 meters long, and has been estimated to have weighed around five tonnes. It had a short nose horn, two long brow horns, and long horns on the jugal bones. Its skull had a very long frill with triangular hornlets on the edge.
context_section_description: The first specimens were collected by Charles Hazelius Sternberg in the San Juan Basin in New Mexico. Sternberg worked in commission for the Swedish Uppsala University. In 1921 he recovered a skull and a rump, specimens PMU R.200 and PMU R.286, at the Meyers Creek near the Kimbetoh Wash in a layer of the Kirtland Formation. He sent these fossils to paleontologist Carl Wiman. In 1922 Sternberg decided to work independently and began a dig north of Tsaya Trading Post, in the Fossil Forest of San Juan County. Here he discovered a complete skeleton, which he sold to the American Museum of Natural History. The museum then sent out a team headed by Charles Mook and Peter Kaisen to assist Sternberg in securing this specimen; subsequent digging by Sternberg in 1923 brought the total of AMNH specimens to four. The rump of the main specimen was discarded by the museum because it had insufficient value as a display.
  The species was named and described by Henry Fairfield Osborn in 1923, as Pentaceratops sternbergii. The generic name means "five-horned face", derived from the Greek penta (πέντα, meaning five), keras (κέρας, horn) and -ops (ὤψ, face), in reference to its two long epijugal bones, spikes which protrude out sidewards from under its eyes, in addition to the three more obvious horns as with Triceratops. Osborn obligingly gave it the specific name sternbergii to honor its discoverer. The name had been suggested to Osborn by William Diller Matthew; the specific epithet served as a consolation to the almost bankrupt Sternberg whose 1923 fossils were initially not acquired by the museum that had to use its 1923/1924 budget to process the finds of the great Asian expeditions by Roy Chapman Andrews.
  The holotype was the skull discovered by Sternberg in 1922, specimen AMNH 6325. It was found in a layer of the Fruitland Formation, dating from the Campanian, about seventy-five million years old. The other three AMNH specimens were AMNH 1624, a smaller skull; AMNH 1622, a pair of brow horns; and AMNH 1625, a piece of skull frill.
  In 1930, Wiman named a second species of Pentaceratops: P. fenestratus. It was based on Sternberg's 1921 specimens and the specific name referred to a hole in the left squamosal. This was later considered to be the same species as Pentaceratops sternbergii and thus a junior synonym, the hole being the likely effect of an injury.
  In 1929 Steinberg's son, George Fryer Sternberg, discovered specimen USNM V12002, a right squamosal. Pentaceratops proved to be a quite common fossil in the Fruitland and Kirtland formations. It has even been used as a guide fossil: the appearance of Pentaceratops sternbergii in the fossil record marks the end of the Judithian land vertebrate age and the start of the Kirtlandian. Subsequent finds include specimens MNA Pl. 1668, MNA Pl. 1747, NMMNH P-27468 and USNM 2416, partial skeletons with skull; YPM 1229, a skeleton lacking the skull; UALP 13342 and UKVP 16100, skulls; UNM B-1701, USNM 12741, USNM 12743, USNM 8604, SMP VP-1596, SMP VP-1488, SMP VP-1500 and SMP VP-1712, fragmentary skulls. Apart from the San Juan Basin finds, a juvenile specimen of Pentaceratops, SDMNH 43470, was found in the Williams Fork Formation of Colorado in 2006.
   
  Sometimes the identification of a specimen as Pentaceratops has proven to be highly contentious. In 1998 Thomas Lehman described OMNH 10165, a very large skull and its associated skeleton found in New Mexico in 1941. The skull is presently on display at the Sam Noble Oklahoma Museum of Natural History, and is the largest Pentaceratops exemplar known, with the distinction of having produced the largest known skull of any land vertebrate. However, in 2011, the skeleton was renamed as a separate genus, Titanoceratops, due to its more derived morphology, similarities to Triceratops, and lack of unique characteristics shared with Pentaceratops.
  In 2014 Nicholas Longrich named a new species: Pentaceratops aquilonius, "the northern one," based on fragmentary fossils discovered during the 1930s near Manyberries in Canada. The species has been described 
caption: Specimen being airlifted with help from the New Mexico National Guard, 2015
exif: {"Image ImageDescription": "Company C, 1st Battalion, 171st Aviation, UH-60 Black Hawk crew consisting of pilots Maj. Daniel Purcell and Capt. Kevin Doo, and crew chiefs Sgt. 1st Class Dennis Cahill and Sgt. Saul Monarez airlift a unique sling load of a baby Pentaceratops dinosaur skull out of the Bisti/De-na-zin Wilderness Area Oct. 29, 2015. Sgt. Bryan Haworth and Spc. Alonzo Romero, both of 1st Battalion 200th Infantry, hook the 4,500 pounds load onto the belly of the aircraft. The New Mexico Army National Guard conducted a civil-military community support project Oct. 28-29, assisting the New Mexico Museum of Natural History and Science in transporting 65 million-year-old Pentaceratops dinosaur fossils from the Bisti and Ah-Shi-Sle-pah Wilderness Areas to the museum in Albuquerque, N.M. (Released, Photo by Sgt. 1st Class Anna Doo, New Mexico National Guard Public Affairs)", "Image Make": "Canon", "Image Model": "Canon EOS 7D", "Image Orientation": "Horizontal (normal)", "Image XResolution": "300", "Image YResolution": "300", "Image ResolutionUnit": "Pixels/Inch", "Image Artist": "Sgt. 1st Class Anna Doo", "Image Copyright": "Public Domain", "Image ExifOffset": "248", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "300", "Thumbnail YResolution": "300", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "880", "Thumbnail JPEGInterchangeFormatLength": "7477", "EXIF ExposureTime": "1/60", "EXIF FNumber": "22", "EXIF ExposureProgram": "Shutter Priority", "EXIF ISOSpeedRatings": "200", "EXIF SensitivityType": "Recommended Exposure Index", "EXIF RecommendedExposureIndex": "200", "EXIF ExifVersion": "0230", "EXIF ShutterSpeedValue": "5906891/1000000", "EXIF ApertureValue": "8918863/1000000", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "3", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "95", "EXIF ColorSpace": "sRGB", "EXIF FocalPlaneXResolution": "5184000/907", "EXIF FocalPlaneYResolution": "691200/119", "EXIF FocalPlaneResolutionUnit": "2", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Manual", "EXIF SceneCaptureType": "Standard", "EXIF BodySerialNumber": "0371713639", "EXIF LensSpecification": "[70, 200, 0/0, 0/0]", "EXIF LensModel": "EF70-200mm f/2.8L IS II USM"}