Boreonykus Temporal range: Late Cretaceous, ~ | |
---|---|
Restoration | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Family: | † Dromaeosauridae |
Genus: | † Boreonykus Bell & Currie, 2015 |
Type species | |
†Boreonykus certekorum Bell & Currie, 2015 |
Boreonykus is an extinct genus of dromaeosaurid dinosaur, that lived during the Late Cretaceous in the area of present Canada.
Fragmentary dromaeosaurid remains were discovered in the eighties at the Pipestone Creek site in central Alberta during excavations of a bonebed containing at least twenty-seven individuals of the ceratopsid Pachyrhinosaurus lakustai . [1] They were initially partly referred to a Saurornitholestes sp in 2001. [2]
The type species Boreonykus certekorum was named and described by Phil Bell and Philip John Currie in 2015. The genus name is a variation of "Boreonychus", "northern claw". The specific name certekorum references the Certek company, that works in the oil industry and provided financial support for the excavations. [1]
The holotype specimen of Boreonykus, TMP 1989.055.0047, was found in a layer of the Wapiti Formation in central Alberta, which dates from the late Campanian, 73.27 ± 0.25 million years ago. It consists of a right frontal bone. Fourteen loose teeth have been referred to the species, as well as several postcranial bones, perhaps of the same individual: the specimen TMP 1988.055.0129, a rear caudal vertebra; UALVP 53597, a claw of the second finger, and the specimen TMP 1986.055.0184.1, a sickle claw of the foot. [1]
A single autapomorphy, unique derived trait, was indicated: the ridges bordering the fronts of the depressions around the supratemporal fenestrae form an acute angle of 55° together, pointing to the rear. [1]
Boreonykus was, within the Dromaeosauridae, placed in the Velociraptorinae. It was seen as both an indication of faunal provincialism and a quick species turn-over rate. [1] However, in 2021, Boreonykus was recovered within the Dromaeosaurinae, restricting the distribution of velociraptorines only to Asia. [3]
Velociraptor is a genus of small dromaeosaurid dinosaurs that lived in Asia during the Late Cretaceous epoch, about 75 million to 71 million years ago. Two species are currently recognized, although others have been assigned in the past. The type species is V. mongoliensis, named and described in 1924. Fossils of this species have been discovered in the Djadochta Formation, Mongolia. A second species, V. osmolskae, was named in 2008 for skull material from the Bayan Mandahu Formation, China.
Dromaeosaurus is a genus of dromaeosaurid theropod dinosaur that lived during the Late Cretaceous period, 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 Hell Creek Formation, Horseshoe Canyon Formation and 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.
Saurornitholestes is a genus of carnivorous dromaeosaurid theropod dinosaur from the late Cretaceous of Canada (Alberta) and the United States.
Atrociraptor is a genus of dromaeosaurid dinosaur that lived during the Late Cretaceous in what is now Alberta, Canada. The first specimen, a partial skull, was discovered in 1995 by the fossil collector Wayne Marshall in the Horseshoe Canyon Formation, about 5 km (3 mi) from the Royal Tyrrell Museum of Palaeontology, where it was brought for preparation. In 2004, the specimen became the holotype of the new genus and species Atrociraptor marshalli; the generic name is Latin for "savage robber", and the specific name references Marshall. The holotype consists of the premaxillae, a maxilla, the dentaries, associated teeth, and other skull fragments. Isolated teeth from the same formation have since been assigned to Atrociraptor.
Bambiraptor is a Late Cretaceous, 72-million-year-old, bird-like dromaeosaurid theropod dinosaur described by scientists at the University of Kansas, Yale University, and the University of New Orleans.
Adasaurus is a genus of dromaeosaurid dinosaur that lived in Asia during the Late Cretaceous period about 70 million years ago. The genus is known from two partial specimens found in the Nemegt Formation of Mongolia that were partially described in 1983 by the paleontologist Rinchen Barsbold.
Chirostenotes is a genus of oviraptorosaurian dinosaur from the late Cretaceous of Alberta, Canada. The type species is Chirostenotes pergracilis.
Pyroraptor is an extinct genus of paravian dinosaur, probably a dromaeosaurid or unenlagiid, from the Late Cretaceous Ibero-Armorican island, of what is now southern France. It lived during the late Campanian and early Maastrichtian stages, approximately 72 million years ago. It is known from a single partial specimen that was found in Provence in 1992, after a forest fire. The animal was named Pyroraptor olympius by Allain and Taquet in 2000.
Zapsalis is a genus of dromaeosaurine theropod dinosaurs. It is a tooth taxon, often considered dubious because of the fragmentary nature of the fossils, which include teeth but no other remains.
Tsaagan is a genus of dromaeosaurid dinosaur from the Djadokhta Formation of the Late Cretaceous of Mongolia.
Dromaeosaurinae is a subfamily of the theropod group Dromaeosauridae. The earliest dromaeosaurine is Utahraptor, dating back to the Early Cretaceous in North America. Some isolated teeth seems to represent an indeterminate species of dromaeosaurine, coming from the Late Jurassic in Africa, which could potentially push their range to an earlier time period.
Austroraptor is a genus of dromaeosaurid theropod dinosaur that lived during the Campanian and Maastrichtian ages of the Late Cretaceous period in what is now Argentina.
The Wapiti Formation is a geological formation of the Western Canada Sedimentary Basin in northwestern Alberta, and northeastern British Columbia, Canada. Its deposition spanned the time interval from the lower Campanian through to the upper Maastrichtian, between approximately 80 and 68 Ma. It was named by G.M. Dawson in 1881, presumably for exposures along the lower part of the Wapiti River and downstream along the Smoky River in Alberta.
Hesperonychus is a genus of small paravian theropod dinosaur. It may be a dromaeosaurid or an avialan. There is one described species, Hesperonychus elizabethae. The type species was named in honor of Dr. Elizabeth Nicholls of the Royal Tyrrell Museum of Palaeontology who collected it as a student in 1982. It is known from fossils recovered from the Dinosaur Park Formation and possibly from the uppermost strata of the Oldman Formation of Alberta, dating to the Campanian stage of the Late Cretaceous around 75 million years ago.
Eudromaeosauria is a subgroup of terrestrial dromaeosaurid theropod dinosaurs. They were small to large-sized predators that flourished during the Cretaceous Period. Eudromaeosaur fossils are known almost exclusively from the northern hemisphere.
This timeline of dromaeosaurid research is a chronological listing of events in the history of paleontology focused on the dromaeosaurids, a group of sickle-clawed, bird-like theropod dinosaurs including animals like Velociraptor. Since the Native Americans of Montana used the sediments of the Cloverly Formation to produce pigments, they may have encountered remains of the dromaeosaurid Deinonychus hundreds of years before these fossils came to the attention of formally trained scientists.
Dakotaraptor is a chimaeric genus of maniraptoriform theropod dinosaur that lived in western North America during the Late Cretaceous period. The remains have been found in the Maastrichtian-aged Hell Creek Formation, dated to the very end of the Mesozoic era, making Dakotaraptor potentially one of the last surviving dromaeosaurids, though other researchers have disputed its classification. The remains of D. steini were discovered in a multi-species bonebed. Elements of the holotype and referred specimens were later found to belong to trionychid turtles, and it is unclear whether further analysis of potential non-dromaeosaurid affinities of the holotype and referred material can be properly conducted, because currently the type specimen is housed in private collection. Phylogenetic analyses of D. steini place it in a variety of positions within Dromaeosauridae.
Latenivenatrix, meaning "hiding huntress", is a genus of large troodontid known from a single species, L. mcmasterae. Along with the contemporary Stenonychosaurus, it is known from non-tooth fossils that were formerly assigned to the now potentially dubious genus Troodon. Although described as separate, it has been considered a junior synonym of Stenonychosaurus.
Cryodrakon is a genus of azhdarchid pterosaur that lived during the Late Cretaceous period in what is now Canada. It contains a single species, Cryodrakon boreas, recovered from the Dinosaur Park Formation.