They have been extinct for millions of years, but Utah dinosaurs are having a record-breaking year. The Bureau of Land Management (BLM), Utah Geological Survey (UGS), and Temple University announce the naming of the seventh dinosaur from BLM Utah in 2010. Geminiraptor suarezarum, found on BLM lands near Green River, UT, is the oldest reported “raptor-like” troodontid dinosaur in North America (125 million years old).

The seven new species of dinosaur described from BLM lands in Utah are notable because every one of them represents a genus that is new to science. Additionally, the National Park Service named a new long-necked dinosaur to bring the state of Utah to a record-breaking total of eight new dinosaurs in 2010! Worldwide, there are about 700 named dinosaurs. This string of dinosaur descriptions means that a full one percent of all known dinosaur species were described from lands in Utah during 2010.

Troodontid dinosaurs like Geminiraptor suarezarum are “raptor-like” dinosaurs often credited with being more intellectually advanced.

This is deduced based on their large cranial capacity compared with the overall size of the animal. In fact, in 1982, an imaginative, intelligent troodontid “dinosauroid” was proposed by Dale Russell of the National Museum Canada, as the logical consequence if dinosaurs had not gone extinct. This fantastic reconstruction has been criticized as being too anthropomorphic, but was based on the fact that the troodontid braincase was as much as six times larger than other dinosaurs.

Most troodontid dinosaurs from North America are dated to 72-75 million years ago.  Geminiraptor, at about 125 million years of age, is easily the oldest. The specimen, housed at the College of Eastern Utah Prehistoric Museum, is a highly distinctive, but incomplete upper jaw inflated by a large and unique air sack that readily identifies the fossil as belonging to a new species of troodontid.

The site, known as the “Suarez Sister’s Site” is located on BLM lands near Green River, UT, and is the second area known to have a mass-mortality assemblage of dinosaurs that include the odd sickle-clawed dinosaur Falcarius (described by Kirkland and others in 2005). The discovery was part of a project on BLM lands funded by the Discovery Channel and the Utah Geological Survey (UGS) and featured on the 2005 Science Channel documentary “Utah’s Dinosaur Graveyard.”  

So many new dinosaurs were discovered during the course of this project, including the new giant iguanodont Iguanacolossus announced last month, that the site was turned over to the College of Eastern Utah for further study. All of the fossils from the “Suarez Sister’s Site” are curated at the College of Eastern Utah’s Prehistoric Museum in Price, UT.

Geminiraptor, meaning “Twin Predatory Thief of the Suarezes” is named in honor of Marina and Selina Suarez, graduate students from Temple University in Philadelphia, PA, who studied the geology of the area in order to reconstruct the paleoclimate of the early Cretaceous Period of North America 125 million years ago.  Marina and Celina went on to complete their Doctorates at the University of Kansas and are presently doctoral fellows at Johns Hopkins and Idaho State University respectively.

Dinosaurs discovered in Utah in 2010:

BLM Lands

1. Diabloceratops eatoni May 28 Kirkland, J. I., and D. D. Deblieux. 2010. New basal centrosaurine ceratopsian skulls from the Wahweap Formation (middle Campanian), Grand Staircase-Escalante National Monument, southern Utah. pp. 117-141 in M. J. Ryan, B. J. Chinnery-Allgeir, and D. A. Eberth. editors. New perspectives on horned dinosaurs, the Royal Tyrrell Museum Ceratopsian Symposium. Indiana University Press, Bloomington and Indianapolis.

2. Seitaad ruessi March 23 Sertich JJW, Loewen MA, 2010 A New Basal Sauropodomorph Dinosaur from the Lower Jurassic Navajo Sandstone of Southern Utah. PLoS ONE 5(3): e9789.doi:10.1371/journal.pone.0009789

3. Utahceratops gettyi September 22

4. Kosmoceratops richardsoni September 22 Sampson SD, Loewen MA, Farke AA, Roberts EM, Forster CA, et al. 2010 New Horned Dinosaurs from Utah Provide Evidence for Intracontinental Dinosaur Endemism. PLoS ONE 5(9): e12292. doi:10.1371/journal.pone.0012292

5. Hippodraco scutodens November 22

6. Iguanacolossus fortis November 22 McDonald AT, Kirkland JI, DeBlieux DD, Madsen SK, Cavin J, et al. 2010 New Basal Iguanodonts from the Cedar Mountain Formation of Utah and the Evolution of Thumb-Spiked Dinosaurs. PLoS ONE 5(11): e14075. doi:10.1371 /journal.pone.0014075

7. Geminiraptor suarezarum December 15 Senter PS, Kirkland JI, Bird J, Bartlett JA. 2010 A new troodontid theropod dinosaur from the Lower Cretaceous of Utah. PLoS ONE 5(12): e14329. doi:10.1371/journal.pone.0014329

National Park Service Lands

8. Abydosaurus mcintoshi February 23 Daniel Chure & Brooks B. Britt & John A. Whitlock & Jeffrey A. Wilson 2010 First complete sauropod dinosaur skull from the Cretaceous of the Americas and the evolution of sauropod dentition. Naturwissenschaften DOI 10.1007/s00114-010-0650-6