Explore The Ceratopsian Wall At Arizona Museum Of Natural History

The Arizona Museum of Natural History has our own version of The Wall in our awesome 75,000,000 B.C. exhibit. Let’s check out its members!
#Crittendenceratops was the first dinosaur named from the ~75 mya Late Cretaceous Fort Crittenden Formation in Arizona (thus its name), a place I have spent looking for dinosaurs. The remains tend to be weathered and beaten up. Dalman et.al. 2018 named it from two individuals with a unique parietosquamosal frill, one that indicates tis a #nasutoceratopsin. They suggested that there are no separate northern and southern #Laramidia #ceratopsian faunas because of this finding.
The unnamed Judith River Formation ceratopsian is from Montana around 75 mya and looks cool with those cool brow horns. ~80% of its skeleton has been recovered, including some skin impression!
#Nasutoceratops was named in 2013 by Sampson et.al. and is a 75 mya #centrosaurine. “Large nosed horned face” has extremely long brow horns (greater than 18”) for a #centrosaur, and that is before any keratinous sheath extends and sharpens them. It has a massive nose with possibly pneumatic nasal bones, if so a first, and a frill with holes in it. The nasal horn is almost non-existent. Those big horns may have been used to “lock up” and tussle with others of their kind, as well as keep them safe from #Teratophoneus.
#Xenoceratops was named in 2023 by Ryan et.al. from Canadian material 77 mya. A Centrosaurine, the parietal (part of the frill) is unique among. “Alien horn face” is so named because it is the first ceratopsian known from the Foremost Formation. Seemingly most formation in Canada have ceratopsians :-) but they are rare here.
#Agujaceratops was named in 2006 by Lucas et.al. as a distinct genus based on differences in the skull bones. #Chasmosaurus mariscalensis, described in 1989 from bones collected in 1938, turned out to be its own genus. Heralding from the Aguja Formation ~76 mya, the adults were rhino-sized with huge brow horns and a big frill. However, the baby you see on display lacked both of those features, having tiny nub horns and a simple frill instead. That is classic ontogeny, where characters appear as one ages.
#FossilCrates #CeratopsianSunday #dinosaur #dinosaurs #paleontology #dinosaurskull #dinosaur🦖🦕 #dinosaurs🦖🦕 #ceratopsians

[@dagoodboy6424]

Ive never had poker face for ceratopcians.

[@FossilCrates]

Now you have :-)

[@Tyrannosauroidea]

If we put all ceratopsian skulls there it would be a mess , I think

[@FossilCrates]

I agree!

[@amirwheeler2842]

Question: what was the fauna and environment Psittacosaurus sibiricus lived along with ? Same with Amargasaurus

[@FossilCrates]

Desert for the former, alluvial flood plains for the latter.

[@thhseeking]

A raptor's trophy wall...

[@FossilCrates]

:-)

[@TheSwanlake2009]

You wonder why today’s buffaloes don’t have beaks and shields only horns

[@DrBC]

Their ancestors didn't have it in their genetics. Mammals don't have ceratopsian shields nor beaks which is why the modern big mammals lack them. It wasn't in their evolutionary toolkit.

[@Bagelgeuse]

Is that baby Agujaceratops a real fossil?

[@DrBC]

It is a cast of actual juvenile Agujaceratop elements