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Deinodon Horridus
''Deinodon'' (Greek for "terrible tooth") is a dubious tyrannosaurid dinosaur genus containing a single species, ''Deinodon horridus''. ''D. horridus'' is known only from a set of teeth found in the Late Cretaceous Judith River Formation of Montana and named by paleontologist Joseph Leidy in 1856.Leidy, J. (1856). "Notices of the remains of extinct reptiles and fishes, discovered by Dr. F.V. Hayden in the badlands of the Judith River, Nebraska Territory." ''Proc. Acad. Nat. Sci.'', 8(2): 72. These were the first tyrannosaurid remains to be described and had been collected by Ferdinand Vandeveer Hayden. The teeth of ''Deinodon'' were slightly heterodont, and the holotype of ''Aublysodon'' can probably be assigned to ''Deinodon''. History and classification It is likely that the fossilized teeth of ''D. horridus'' belonged to the dinosaur later identified as ''Gorgosaurus libratus''. In a 1922 study, William Diller Matthew & Barnum Brown found that the teeth of ''D. horridus'' and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dale Russell
Dale Alan Russell (27 December 1937 – 21 December 2019) was an American-Canadian geologist and palaeontologist. Throughout his career Russell worked as the Curator of Fossil Vertebrates at the Canadian Museum of Nature, Research Professor at the Department of Marine Earth and Atmospheric Sciences (MEAS) at North Carolina State University, and Senior Paleontologist at the North Carolina Museum of Natural Sciences. Dinosaurs he has described include '' Daspletosaurus'' and ''Dromiceiomimus'', and he was amongst the first paleontologists to consider an extraterrestrial cause (supernova, comet, asteroid) for the Cretaceous–Paleogene extinction event. Russell also helped lead the China-Canada Dinosaur Project from 1986 to 1991. In 1982, Russell created the "dinosauroid" thought experiment, which speculated an evolutionary path for ''Troodon'' if it had not gone extinct in the Cretaceous–Paleogene extinction event The Cretaceous–Paleogene (K–Pg) extinction event (als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarbosaurus Bataar
''Tarbosaurus'' ( ; meaning "alarming lizard") is a genus of tyrannosaurid dinosaur that flourished in Asia about 70 million years ago, 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. Although many species have been named, modern paleontologists recognize only one, ''T. bataar'', as valid. Some experts see this species as an Asian representative of the North American genus ''Tyrannosaurus''; this would make the genus ''Tarbosaurus'' redundant. ''Tarbosaurus'' and ''Tyrannosaurus'', if not synonym (taxonomy), synonymous, are considered to be at least closely related genera. ''Alioramus'', also from Mongolia, has previously been thought by some authorities to be the closest relative of ''Tarbosaurus'', though this has since been disproven with the discovery of ''Qian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gorgosaurus Libratus
''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. Like most known tyrannosaurids, ''Gorgosaurus'' was a large bipedal predator, measuring in length and in body mass. Dozens of large, sharp teeth lined its jaws, while its two-fingered forelimbs were comparatively small. ''Gorgosaurus'' was most closely related to ''Albertosaurus'', and more distantly related to the larger ''Tyrannosaurus''. ''Gorgosaurus'' and ''Albertosaurus'' are extremely similar, distinguished mainly by subtle differences in the teeth and skull bones. Some experts consider ''G. libratus'' to be a species of ''Albertosaurus''; thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albertosaurus
''Albertosaurus'' (; meaning "Alberta lizard") is a genus of tyrannosaurid theropod dinosaurs that lived in western North America during the Late Cretaceous Period, about 71 million years ago. The type species, ''A. sarcophagus'', was apparently restricted in range to the modern-day Canadian province of Alberta, after which the genus is named, although an indeterminate species ("cf. ''Albertosaurus'' sp.") has been discovered in the Corral de Enmedio and Packard Formations in Mexico. Scientists disagree on the content of the genus, with some recognizing ''Gorgosaurus libratus'' as a second species. As a tyrannosaurid, ''Albertosaurus'' was a bipedal predator with tiny, two-fingered hands and a massive head that had dozens of large, sharp teeth. It may have been an apex predator in its local ecosystem. While ''Albertosaurus'' was large for a theropod, it was much smaller than its larger and more famous relative ''Tyrannosaurus rex'', growing up to in length and weighing . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albertosaurus Sarcophagus
''Albertosaurus'' (; meaning "Alberta lizard") is a genus of tyrannosaurid theropod dinosaurs that lived in western North America during the Late Cretaceous Period, about 71 million years ago. The type species, ''A. sarcophagus'', was apparently restricted in range to the modern-day Canadian province of Alberta, after which the genus is named, although an indeterminate species ("cf. ''Albertosaurus'' sp.") has been discovered in the Corral de Enmedio and Packard Formations in Mexico. Scientists disagree on the content of the genus, with some recognizing ''Gorgosaurus libratus'' as a second species. As a tyrannosaurid, ''Albertosaurus'' was a bipedal predator with tiny, two-fingered hands and a massive head that had dozens of large, sharp teeth. It may have been an apex predator in its local ecosystem. While ''Albertosaurus'' was large for a theropod, it was much smaller than its larger and more famous relative ''Tyrannosaurus rex'', growing up to in length and weighing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithomimus
''Ornithomimus'' (; "bird mimic") is a genus of ornithomimid dinosaurs from the Late Cretaceous Period of what is now North America. ''Ornithomimus'' was a swift bipedal theropod which fossil evidence indicates was covered in feathers, equipped with a small toothless beak that may indicate an omnivorous diet. It is usually classified into two species: the type species, ''Ornithomimus velox'', and a referred species, ''Ornithomimus edmontonicus''. ''O. velox'' was named in 1890 by Othniel Charles Marsh on the basis of a foot and partial hand from the late Maastrichtian-age Denver Formation of Colorado, United States. Another seventeen species have been named since, though most of them have subsequently been assigned to new genera or shown to be not directly related to ''Ornithomimus velox''. The best material of species still considered part of the genus has been found in Alberta, Canada, representing the species ''O. edmontonicus'', known from several skeletons from the early Maast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aublysodon Cristatus
''Aublysodon'' (“backwards-flowing tooth") is a genus of carnivorous dinosaurs known only from the Judith River Formation in Montana, which has been dated to the late Campanian age of the late Cretaceous period (about 75 million years ago). The only currently recognized species, ''Aublysodon mirandus'', was named by paleontologist Joseph Leidy in 1868. It is now considered dubious, because the type specimen consists only of an isolated premaxillary (front) tooth. Although this specimen is now lost, similar teeth have been found in many US states, western Canada, and Asia. These teeth almost certainly belong to juvenile tyrannosaurine tyrannosaurids, but most have not been identified to species level. However, it is likely that the type tooth (and therefore the name ''Aublysodon mirandus'' itself) belongs to one of the species in the genus ''Daspletosaurus'', which was present in contemporary formations, and which matches specific details of the original tooth. The synapomorphies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aublysodon Amplus
''Aublysodon'' (“backwards-flowing tooth") is a genus of carnivorous dinosaurs known only from the Judith River Formation in Montana, which has been dated to the late Campanian age of the late Cretaceous period (about 75 million years ago). The only currently recognized species, ''Aublysodon mirandus'', was named by paleontologist Joseph Leidy in 1868. It is now considered dubious, because the type specimen consists only of an isolated premaxillary (front) tooth. Although this specimen is now lost, similar teeth have been found in many US states, western Canada, and Asia. These teeth almost certainly belong to juvenile tyrannosaurine tyrannosaurids, but most have not been identified to species level. However, it is likely that the type tooth (and therefore the name ''Aublysodon mirandus'' itself) belongs to one of the species in the genus '' Daspletosaurus'', which was present in contemporary formations, and which matches specific details of the original tooth. The synapomorp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dromaeosaurus Laevifrons
''Dromaeosaurus'' (, "running lizard") is a genus of Dromaeosauridae, dromaeosaurid theropod dinosaur which lived during the Late Cretaceous period (middle late Campanian and Maastrichtian), sometime between 80 and 69 million years ago, in Alberta, Canada and the western United States. The type (biology), type species is ''Dromaeosaurus albertensis'', which was described by William Diller Matthew and Barnum Brown in 1922 in paleontology, 1922. Its fossils were unearthed in the Dinosaur Park Formation. Teeth attributed to this genus have been found in the Prince Creek Formation. ''Dromaeosaurus'' is the type genus of both Dromaeosauridae and Dromaeosaurinae, which include many genera with similar characteristics to ''Dromaeosaurus'' such as possibly its closest relative ''Dakotaraptor''. ''Dromaeosaurus'' was heavily built, more so than other dromaeosaurs that are similar in size, like ''Velociraptor''. Discovery and naming Despite receiving widespread attention in popular books o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Troodon Formosus
''Troodon'' ( ; ''Troödon'' in older sources) is a wastebasket taxon and a dubious genus of relatively small, bird-like dinosaurs known definitively from the Campanian age of the Late Cretaceous period (about 77 mya). It includes at least one species, ''Troodon formosus'', known from Montana. Discovered in October 1855, ''T. formosus'' was among the first dinosaurs found in North America, although it was thought to be a lizard until 1877. Several well-known troodontid specimens from the Dinosaur Park Formation in Alberta were once believed to be members of this genus. However, recent analyses in 2017 have found the genus to be undiagnostic and referred some of these specimens to the genus ''Stenonychosaurus'' (long believed to be synonymous with ''Troodon'') and others to the genus ''Latenivenatrix''. The genus name is Ancient Greek for "wounding tooth", referring to the teeth, which were different from those of most other theropods known at the time of their discovery. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dromaeosaurus Falculus
''Dromaeosaurus'' (, "running lizard") is a genus of dromaeosaurid theropod dinosaur which lived during the Late Cretaceous period (middle late Campanian and Maastrichtian), sometime between 80 and 69 million years ago, in Alberta, Canada and the western United States. The type species is ''Dromaeosaurus albertensis'', which was described by William Diller Matthew and Barnum Brown in 1922. Its fossils were unearthed in the Dinosaur Park Formation. Teeth attributed to this genus have been found in the Prince Creek Formation. ''Dromaeosaurus'' is the type genus of both Dromaeosauridae and Dromaeosaurinae, which include many genera with similar characteristics to ''Dromaeosaurus'' such as possibly its closest relative ''Dakotaraptor''. ''Dromaeosaurus'' was heavily built, more so than other dromaeosaurs that are similar in size, like ''Velociraptor''. Discovery and naming Despite receiving widespread attention in popular books on dinosaurs, and the usage of a complete mounted skele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
