Open Paleo

Centrosaurinae

Lambe, 1915 Type genus Centrosaurus

Its genera lived 83.6–66.0 million years ago Late Cretaceous
Late Cretaceous stages

Centrosaurinae is one of the two subfamilies of horned ceratopsid dinosaurs, encompassing large quadrupedal herbivores of the Late Cretaceous. Its fossils come primarily from the northern part of Laramidia, in present-day Alberta, Montana, and Alaska, with isolated members reaching as far south as Utah and Mexico and one debated occurrence in China. Centrosaurines are typically marked by a prominent nasal horn, short horns over the eyes, and an ornamented frill projecting from the back of the skull, and are relatively small for ceratopsids, roughly the size of a rhinoceros at body lengths of about 2.5 to 8 meters. The subfamily is divided into several tribes, including the early-diverging nasutoceratopsins and albertaceratopsins and the more derived centrosaurins and pachyrhinosaurins; the last group replaces the nasal horn with a thickened bony boss. Their classification is complicated by wide variation between individuals and growth stages, and Wilson and colleagues (2020) could not reject the hypothesis that the eucentrosaurans evolved as a single changing lineage, with Stellasaurus as a transitional form.

Diagnosis

  1. Cranial ornamentation concentrated on the nasal region and parietal margin, with large blade-like epiparietals (more than six loci per side in derived forms)
  2. Rostrocaudally abbreviated squamosal with a stepped caudomedian margin
  3. Wide parietal midline bar with a triangular cross-section that tapers laterally
  4. Premaxilla with a pronounced ventral angle and a subcircular external narial region
  5. Narial spine formed by both the nasal and the premaxilla

Genera placed directly in Centrosaurinae

  • Achelousaurus Sampson, 1995 Campanian (83.6–72.2 Ma)United States
  • Albertaceratops Ryan, 2007 Campanian (83.6–72.2 Ma)Canada
  • Avaceratops Dodson, 1986 Campanian (83.6–72.2 Ma)United States
  • Brachyceratops Nomen dubium Gilmore, 1914 Campanian (83.6–72.2 Ma)United Statesincertae sedis
  • Centrosaurus Lambe, 1905 Campanian (83.6–72.2 Ma)Canada
  • Coronosaurus Ryan et al., 2012 Campanian (83.6–72.2 Ma)Canada
  • Crittendenceratops Dalman et al., 2018 Campanian (83.6–72.2 Ma)United States
  • Diabloceratops Kirkland & DeBlieux, 2010 Campanian (83.6–72.2 Ma)United States
  • Einiosaurus Sampson, 1995 Campanian (83.6–72.2 Ma)United States
  • Furcatoceratops Ishikawa et al., 2023 Campanian (83.6–72.2 Ma)United States
  • Lokiceratops Loewen et al., 2024 Campanian (83.6–72.2 Ma)United States
  • Machairoceratops Lund et al., 2016 Campanian (83.6–72.2 Ma)United States
  • Medusaceratops Ryan et al., 2010 Campanian (83.6–72.2 Ma)United States
  • Menefeeceratops Dalman et al., 2021 Campanian (83.6–72.2 Ma)United States
  • Monoclonius Nomen dubium Cope, 1876 Campanian (83.6–72.2 Ma)United Statesincertae sedis
  • Nasutoceratops Sampson et al., 2013 Campanian (83.6–72.2 Ma)United States
  • Pachyrhinosaurus Sternberg, 1950 Campanian–Maastrichtian (83.6–66.0 Ma)Canada
  • Sinoceratops Xu et al., 2010 Campanian (83.6–72.2 Ma)China
  • Spinops Farke et al., 2011 Campanian (83.6–72.2 Ma)Canada
  • Stellasaurus Wilson et al., 2020 Campanian (83.6–72.2 Ma)United States
  • Styracosaurus Lambe, 1913 Campanian (83.6–72.2 Ma)Canada
  • Wendiceratops Evans & Ryan, 2015 Campanian (83.6–72.2 Ma)Canada
  • Xenoceratops Ryan et al., 2012 Campanian (83.6–72.2 Ma)Canada
  • Yehuecauhceratops Rivera-Sylva et al., 2017 Campanian (83.6–72.2 Ma)Mexico

References

  1. Lambe, L. M. (1915). On Eoceratops canadensis, gen. nov., with remarks on other genera of Cretaceous horned dinosaurs. Geological Survey of Canada Museum Bulletin 12(24).

    Erected the subfamilies Centrosaurinae and Chasmosaurinae.

    lambe1915a
  2. Wilson, J. P.; Ryan, M. J.; Evans, D. C. (2020). A new, transitional centrosaurine ceratopsid from the Upper Cretaceous Two Medicine Formation of Montana and the evolution of the 'Styracosaurus-line' dinosaurs. Royal Society Open Science 7(4). The Royal Society. doi:10.1098/rsos.200284

    Described Stellasaurus and could not reject its place as a transitional taxon within an anagenetic lineage of eucentrosaurans.

    wilson2020a