Hi everyone! I would like to welcome you to Terrific Tetanurae! #3, a series in which I will explore the weird and wonderful dinosaurs which make up the clade tetanurae! Thanks for reading, and I hope you enjoy the article!
Hi everyone, welcome to Terrific Tetanurae! This week the dinosaur in question is Tanycolagreus topwilsoni, an obscure coelurid from the Morrison Formation. It all began it 1995 when WPL (Western Paleontology Laboratories Inc.) uncovered a partial dinosaur skeleton from Bone Cabin Quarry in Wyoming. The site is part of the Salt Wash Member of the Morrison Formation, and the site dates to the Kimmeridgian epoch of the Jurassic period, around 153 million years ago. Originally considered a species of Coelurus, Tanycolagreus was only described as a separate genus by Kenneth Carpenter et. al. in 2005. The taxonomy of the animal is dubious, as with the rest of coeluridae, which has been considered a group within compsognathidae, tyrannosauroidae, and everything in-between. During the late Jurassic period, the Bone Cabin Quarry was a wet environment and many different aquatic animals lived there. Tanycolagreus may have preyed upon this animals, but as of now, we have no fossil evidence of this behavior. It was most likely a primarily terrestrial carnivore, preying on small to medium sized animals. Tanycolagreus was actually fairly large for a coelurid, the holotype an estimated 11 feet long. A partial pre maxilla from the Cleveland-Lloyd Quarry also assigned to Tanycolagreus is estimated to have come from an individual around 13 feet long. Tanycolagreus was most likely a secondary predator, surviving in the shadows of the macro-predatory allosaurids and megalosaurids. Eventually, relatives of Tanycolagreus would come out of the shadows and evolve into one of the most diverse groups of vertebrates ever, the birds.
1. Miles, C.A., Carpenter, K. and Cloward, K.C.,1998, “A new skeleton of Coelurus fragilis from the Morrison Formation of Wyoming”, Journal of Vertebrate Paleontology 18(3): 64A
2. Carpenter, K., Miles, C.A., and Cloward, K.C. 2005. “New small theropod from the Upper Jurassic Morrison Formation of Wyoming.” The Carnivorous Dinosaurs. Indiana University Press, Bloomington: 23-48 3. Senter, P. 2007. “Appendix.” Jurassic West: The Dinosaurs of the Morrison Formation and Their World. Indiana University Press. pp. 327-329