Gargoyleosaurus: Beast of the Week

Ever look up at buildings in the city and see monsters carved out of stone that act as rainspouts?  Those are gargoyles.  Gargoyles are interesting because there are really no rules or guidelines for what they are supposed to look like, unlike a lot of other popular monsters.  Well, our dinosaur this week must have inspired something spooky in paleontologists because it is named after these fantastic stone guardians of the night...that also barf rain.  Check out Gargoyleosaurus parkpinorum!

Gargoyleosaurus fending off a group of Allosaurus.  Watercolor by Christopher DiPiazza.

Gargoyleosaurus lived during the Late Jurassic period between 154 to 150 million years ago in what is now Wyoming, USA.  It measured about 10 feet (3 meters) long from snout to tail and would have eaten plants when alive.  It was an ankylosaur, which means it had heavy bone armor all over its body like its more famous relative, Ankylosaurus.  Gargoyleosaurus is one of the oldest known ankylosaurs, having been from the Jurassic, whereas the vast majority of ankylosaurs on the fossil record lived later in the Cretaceous.  When alive, Gargoyleosaurus would have shared its environment with other dinosaurs, like Stegosaurus and Allosaurus.

Gargoyleosaurus skeleton on display at the Denver Museum of Nature and Science.

Gargoyleosaurus had a long, narrow snout and body was adorned with flat, triangular spikes running down each flank.  Most of the armor on its back consisted slightly keeled scutes, with a wide solid plate, called a sacral shield, over the hips.  The tail had some small spikes running down the sides as well, but lacked a bony club at the tip, commonly seen in more popular ankylosaurs.  Later on during the Cretaceous, we can see two distinct kinds of armored dinosaurs, the ankylosaurids, which had short snouts and bony tail clubs, and the nodosaurids, which had longer, narrower snouts, and typically had sharp spiky plates running down their sides with no tail club.  Gargoyleosaurus appears to have be part of the nodosaurid lineage of ankylosaurs, which suggests that nodosaurids appeared first, with the club-tailed ankylosaurids evolving later in the Cretaceous.

That's all for this week!  As always feel free to comment below or on our facebook page!

References

Carpenter, K., Miles, C. and Cloward, K. (1998). "Skull of a Jurassic ankylosaur (Dinosauria)." Nature 393: 782-783.

Foster, J. (2007). "Appendix." Jurassic West: The Dinosaurs of the Morrison Formation and Their World. Indiana University Press. pp. 327-329.

Killbourne, B. and Carpenter, K. (2005). "Redescription of Gargoyleosaurus parkpinorum, a polacanthid ankylosaur from the Upper Jurassic of Albany County, Wyoming". Neues Jahrbuch für Geologie und Paläontologie, 237, 111-160.

Soto-Acuña, Sergio; Vargas, Alexander O.; Kaluza, Jonatan; Leppe, Marcelo A.; Botelho, Joao F.; Palma-Liberona, José; Simon-Gutstein, Carolina; Fernández, Roy A.; Ortiz, Héctor; Milla, Verónica; Aravena, Bárbara (2021). "Bizarre tail weaponry in a transitional ankylosaur from subantarctic Chile". Nature. 600 (7888): 259–263.