Tyrannosauridae is a family of coelurosaurian theropod dinosaurs that comprises two subfamilies containing up to thirteen genera, including the eponymous Tyrannosaurus. The exact number of genera is controversial, with some experts recognizing as few as three. All of these animals lived near the end of the Cretaceous Period and their fossils have been found only in North America and Asia.
Tarbosaurus is a genus of tyrannosaurine theropod dinosaur that lived in Asia about 70 million years ago, during the Maastrichtian age at the end of the Late Cretaceous period, considered to contain a single known species: Tarbosaurus bataar. Fossils have been recovered from the Nemegt Formation of Mongolia, with more fragmentary remains found further afield in the Subashi Formation of China.
Daspletosaurus is a genus of tyrannosaurid dinosaur that lived in Laramidia between about 78 and 74.4 million years ago, during the Late Cretaceous Period. The genus Daspletosaurus contains three named species. Fossils of the earlier type species, D. torosus, have been found in Alberta, while fossils of a later species, D. horneri, have been found only in Montana. D. wilsoni has been suggested as an intermediate species between D. torosus and D. horneri that evolved through anagenesis, but this theory has been disputed by other researchers. There are also multiple specimens which may represent new species of Daspletosaurus from Alberta and Montana, but these have not been formally described. The taxon Thanatotheristes has been suggested to represent a species of Daspletosaurus, D. degrootorum, but this has not been widely supported. Daspletosaurus is closely related to the much larger and more recent tyrannosaurid Tyrannosaurus rex. Like most tyrannosaurids, Daspletosaurus was a large bipedal predator, measuring around 8.5–9 metres (28–30 ft) long and weighing up to 2–3 metric tons, equipped with dozens of large, sharp teeth. Daspletosaurus had the small forelimbs typical of tyrannosaurids, although they were proportionately longer than in other genera.
Gorgosaurus is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period (Campanian), between about 76.6 and 75.1 million years ago. Fossil remains have been found in the Canadian province of Alberta and the U.S. state of Montana. Paleontologists recognize only the type species, G. libratus, although other species have been erroneously referred to the genus.
Appalachiosaurus is a genus of basal eutyrannosaurian theropod dinosaur from the middle Campanian age of the Late Cretaceous period of what is now eastern North America. Like most theropods, it was a bipedal predator. Only a juvenile skeleton has been found, representing an animal approximately 6.5 metres (21 ft) long and weighing 623 kilograms (1,373 lb), which indicates an adult would have been significantly larger. It is the most completely known theropod from eastern North America.
Alioramus is a genus of tyrannosaurid theropod dinosaurs from the Late Cretaceous period of Asia. It currently contains two species. The type species, A. remotus is known from a partial skull and three foot bones recovered from the Mongolian Nemegt Formation, which was deposited in a humid floodplain about 70 million years ago. These remains were named and described by Soviet paleontologist Sergei Kurzanov in 1976. A second species, A. altai, known from a much more complete skeleton also from the Nemegt Formation, was named and described by Stephen L. Brusatte and colleagues in 2009. Its relationships to other tyrannosaurid genera were at first unclear, with some evidence supporting a hypothesis that Alioramus was closely related to the contemporary species Tarbosaurus bataar. However, the discovery of Qianzhousaurus indicates that it belongs to a distinct branch of tyrannosaurs, namely the tribe Alioramini.
Hagryphus is a monospecific genus of caenagnathid dinosaur from southern Utah that lived during the Late Cretaceous in what is now the Kaiparowits Formation of the Grand Staircase–Escalante National Monument. The type and only species, Hagryphus giganteus, is known only from an incomplete but articulated left manus and the distal portion of the left radius. It was named in 2005 by Lindsay E. Zanno and Scott D. Sampson. Hagryphus has an estimated length of 2.4–3 metres and weight of 50 kilograms.
Tyrannosaurinae is one of the two extinct subfamilies of Tyrannosauridae, a family of coelurosaurian theropods that consists of at least three tribes and several genera. All fossils of these genera have been found in the Late Cretaceous deposits of western North America and east Asia. Compared to the related subfamily Albertosaurinae, tyrannosaurines overall are more robust and larger though the alioramins were gracile by comparison. This subfamily also includes the oldest known tyrannosaurid genus Lythronax as well as the youngest and most famous member of the group, Tyrannosaurus rex. There were at least 30 different species of tyrannosaurines.
The Kaiparowits Formation is a sedimentary rock formation found in the Kaiparowits Plateau in Grand Staircase–Escalante National Monument, in the southern part of Utah in the western United States. It is over 2800 feet thick, and is Campanian in age. This Upper Cretaceous formation was formed from alluvial floodplains of large rivers in coastal southern Laramidia; sandstone beds are the deposit of rivers, and mudstone beds represent floodplain deposits. It is fossiliferous, with most specimens from the lower half of the formation, but exploration is only comparatively recent, with most work being done since 1982. It has been estimated that less than 10% of the Kaiparowits formation has been explored for fossils. Most fieldwork has been conducted by The Natural History Museum of Utah.
The Wahweap Formation of the Grand Staircase–Escalante National Monument is a geological formation in southern Utah and northern Arizona, around the Lake Powell region, whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.
Diabloceratops is an extinct genus of centrosaurine ceratopsian dinosaur that lived approximately 81.4-81 million years ago during the latter part of the Cretaceous Period in what is now Utah, in the United States. Diabloceratops was a medium-sized, moderately built, ground-dwelling, quadrupedal herbivore, that could grow up to an estimated 4.5 metres (15 ft) in length and 1.3 metric tons in body mass. At the time of its discovery, it was the oldest-known ceratopsid, and first centrosaurine known from latitudes south of the U.S. state of Montana. The generic name Diabloceratops means "devil-horned face," coming from Diablo, Spanish for "devil," and ceratops, Latinized Greek for "horned face." The specific name honors Jeffrey Eaton, a paleontologist at Weber State University and long time friend of the lead author Jim Kirkland. Eaton had a big role in establishing the Grand Staircase-Escalante National Monument where the specimen was found. The type species, Diabloceratops eatoni, was named and described in 2010 by James Ian Kirkland and Donald DeBlieux.
Bistahieversor, also known as the "Bisti Beast", is a genus of basal eutyrannosaurian theropod dinosaur. The genus contains only a single known species, B. sealeyi, described in 2010, from the Late Cretaceous of New Mexico. The holotype and a juvenile were found in the Hunter Wash Member of the Kirtland Formation, while other specimens came from the underlying Fossil Forest member of the Fruitland Formation. This dates Bistahieversor approximately 75.5 to 74.5 million years ago during the Campanian age, found in sediments spanning a million years.
Utahceratops is an extinct genus of ceratopsian dinosaur that lived approximately 76.4~75.5 million years ago during the Late Cretaceous period in what is now Utah. Utahceratops was a large-sized, robustly-built, ground-dwelling, quadrupedal herbivore, that could grow up to an estimated 4.5–5 m (15–16 ft) long.
Zhuchengtyrannus is a genus of tyrannosaurid theropod dinosaur known from the Campanian stage of the Late Cretaceous of Shandong Province, China. It belongs to the subfamily Tyrannosaurinae, and contains a single species, Zhuchengtyrannus magnus.
Talos is an extinct genus of carnivorous bird-like theropod dinosaur, an advanced troodontid which lived during the late Cretaceous period in the geographic area that is now Utah, United States.
Lythronax is a genus of tyrannosaurid dinosaur that lived in North America around 81.9-81.5 million years ago during the Late Cretaceous period. The only known specimen was discovered in Utah in the Wahweap Formation of the Grand Staircase–Escalante National Monument in 2009, and it consists of a partial skull and skeleton. In 2013, it became the basis of the new genus and species Lythronax argestes; the generic name Lythronax means "gore king", and the specific name argestes originates from the Greek poet Homer's name for the wind from the southwest, in reference to the specimen's geographic provenance in North America.
This timeline of tyrannosaur research is a chronological listing of events in the history of paleontology focused on the tyrannosaurs, a group of predatory theropod dinosaurs that began as small, long-armed bird-like creatures with elaborate cranial ornamentation but achieved apex predator status during the Late Cretaceous as their arms shrank and body size expanded. Although formally trained scientists did not begin to study tyrannosaur fossils until the mid-19th century, these remains may have been discovered by Native Americans and interpreted through a mythological lens. The Montana Crow tradition about thunder birds with two claws on their feet may have been inspired by isolated tyrannosaurid forelimbs found locally. Other legends possibly inspired by tyrannosaur remains include Cheyenne stories about a mythical creature called the Ahke, and Delaware stories about smoking the bones of ancient monsters to have wishes granted.
Akainacephalus is a monospecific genus of ankylosaurid dinosaur from southern Utah that lived during the Late Cretaceous in what is now the Horse Mountain Gryposaur Quarry of the Kaiparowits Formation. The type and only species, Akainacephalus johnsoni, is known from the most complete ankylosaur specimen ever discovered from southern Laramidia, including a complete skull, tail club, a number of osteoderms, limb elements and part of its pelvis, among other remains. It was described in 2018 by Jelle P. Wiersma and Randall B. Irmis. It is closely related and shares similar cranial anatomy to Nodocephalosaurus.
Dynamoterror is a monospecific genus of tyrannosaurid dinosaur from New Mexico that lived during the Late Cretaceous in what is now the upper Allison Member of the Menefee Formation. The type and only species, Dynamoterror dynastes, is known from a subadult or adult individual about 9 metres long with an incomplete associated skeleton. It was named in 2018 by Andrew T. McDonald, Douglas G. Wolfe and Alton C. Dooley, Jr. Dynamoterror was closely related to Teratophoneus and Lythronax.
Thanatotheristes is a genus of tyrannosaurid dinosaur from the Late Cretaceous of Laramidia, approximately 80.1-79.5 Ma. Thanatotheristes contains only one species, T. degrootorum. Fossils of this taxon are found in the Foremost Formation of Alberta, Canada, coexisting with medium-sized ceratopsids like Xenoceratops foremostensis and small pachycephalosaurids like Colepiocephale lambei.
