Aquilops: Prehistoric Animal of the Week

Today we will be learning about a newly discovered kind of dinosaur that sets the record for oldest ceratopsian (beaks and frills) ever discovered in North America!  Check out Aquilops americanus!  

Aquilops was a plant-eating dinosaur that lived in what is now Montana, USA, during the Early Cretaceous Period, between 104 and 108 million years ago.  It was tiny, only two feet long from beak to tail, but was a very early member of the ceratopsian group of dinosaurs, which includes the very famous, Triceratops.  The genus name, Aquilops, translates to “eagle face” in reference to the dinosaur’s hooked beak.  The species name, americanus, is because it lived...in America.

Aquilops life reconstruction by Christopher DiPiazza.

 Even though Aquilopsis only known from a single skull, it is a very important find that provides a lot of information about dinosaur evolution.  Never before has a ceratopsian fossil as old as Aquilops been discovered in North America.  The next oldest in the continent is Zuniceratops, at 90 million years old.  Aquilops proves that ceratopsian dinosaurs migrated to North America from Asia (where Yinlong, the oldest known member of the group was found) earlier than previously thought.  

Skull of Aquilops americanus.  Photo provided by Andrew Farke.

Aquilops has a few interesting features about it physically.  Most noticeable is the small bump (called a boss) that appears at the front of its beak.  In life, when the beak was covered in a layer of keratin, there may have been a point there, like a horn, or maybe extended keeled edge to it.  The beak itself curved downwards and ended in a sharp point which may have aided the animal in selectively feeding on vegetation.  Inside its mouth, it had three long teeth coming from the top which may have helped the little fellow to strip soft leaves off of plants.  Some people hypothesize that ceratopsians like Aquilops may have been omnivorous as well, supplementing their diets with meat from time to time, possibly insects or carrion.  In the back of its mouth, Aquilops had rows of small teeth that appear to have been good for crushing plant material.  It also had proportionally huge, round eye sockets and when alive, may have been crepuscular, most active at dawn and dusk, or maybe even nocturnal, most active at night, to help avoid predation.  On the back of the skull Aquilops had a small frill and pointed jugal bones (cheek bones) on either side of its face behind the eyes.  It was probably able to walk on its hind legs or on all fours if it wanted to.  We can hypothesize this based on the limb proportions we see in other early ceratopids like Yinlong and Archaeoceratops.

That is all for this week!  Also special thanks to paleontologist, Andrew Farke, for lending his expert input on my painting and review of this amazing little dinosaur.  Stay tuned for next week when I review the last prehistoric animal of 2014! (It's going to be a big one.) If you have any requests for the upcoming beasties please do not hesitate to comment below or on our facebook page. 

References

 Farke, Andrew A.; Maxwell, W. Desmond; Cifelli, Richard L.; Wedel, Mathew J. (2014-12-10). "A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America, and the Biogeography of Neoceratopsia". PLoS ONE 9 (12). doi:10.1371/journal.pone.0112055.