Open Paleo

Machairoceratops

Lund et al., 2016 mah-KY-ro-SEH-ruh-tops

From Greek machairis (bent sword) combined with ceratops (horned face); meaning "bent sword horned face", referring to the two forward-curving frill horns

83.6–72.2 million years ago Campanian, Late Cretaceous
Late Cretaceous stages

Machairoceratops , previously known as the "Wahweap centrosaurine B", is an extinct genus of centrosaurine ceratopsian dinosaur known from the Late Cretaceous Wahweap Formation (late Campanian stage) of Grand Staircase-Escalante National Monument, southern Utah, United States.

Diagnosis

  1. Posteriorly projecting, anteriorly curved spike-like epiparietal (p1) ornamentation with unique posteromedially directed sulcus
  2. Fan-shaped, subrectangular (rather than rectangular) stepped squamosal
  3. Smaller, elliptical (rather than tetrahedral) epijugal inferred from epijugal contact facet
  4. Anterodorsally (rather than laterally) curved epiparietal ornamentations on either side of midline embayment
  5. Triangular (rather than rounded) parietosquamosal frill

Species

Machairoceratops cronusi Lund et al., 2016

Type species

Named for Cronus, the Greek god who deposed his father Uranus using a curved bladed weapon, alluding to the forward-curving horns on the frill of this ceratopsian.

Holotype
UMNH VP 20550 , Utah Museum of Natural History
Material
Partial skull including eye socket horncores, left jugal, nearly complete braincase, left squamosal, and parietal bone complex
Horizon
Coyote Point Member, Wahweap Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
Star Seep, Utah, United States

References

  1. Lund, E. K.; O'Connor, P. M.; Loewen, M. A.; Jinnah, Z. A. (2016). A New Centrosaurine Ceratopsid, Machairoceratops cronusi gen et sp. nov., from the Upper Sand Member of the Wahweap Formation (Middle Campanian), Southern Utah. PLOS ONE 11(5): e0154403. Public Library of Science (PLoS). doi:10.1371/journal.pone.0154403 lund2016a
  2. Beveridge, T. L.; Roberts, E. M.; Ramezani, J.; Titus, A. L.; Eaton, J. G.; Irmis, R. B.; Sertich, J. J. W. (2022). Refined geochronology and revised stratigraphic nomenclature of the Upper Cretaceous Wahweap Formation, Utah, U.S.A. and the age of early Campanian vertebrates from southern Laramidia. Palaeogeography, Palaeoclimatology, Palaeoecology 591: 110876. Elsevier BV. doi:10.1016/j.palaeo.2022.110876

    Formalizes the Wahweap members and places the holotype quarry in the Coyote Point Member.

    beveridge2022a