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Campanian dinosaurs

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Velociraptor
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 (Mya). 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. A possible record is known from the Nemegt Formation.
Parasaurolophus
Parasaurolophus (; meaning "beside crested lizard" in reference to Saurolophus) is a genus of hadrosaurid "duck-billed" dinosaur that lived in what is now western North America and possibly Asia during the Late Cretaceous period, about 76.5–73 million years ago. It was a large herbivore that could reach over long and weigh over , and were able to move as a biped and a quadruped. Three species are universally recognized: P. walkeri (the type species), P. tubicen, and the short-crested P. cyrtocristatus. Additionally, a fourth species, P. jiayinensis, has been proposed, although it is more commo
Oviraptor
Oviraptor (; ) is a genus of oviraptorid dinosaur that lived in Asia during the Late Cretaceous period. The first remains were collected from the Djadokhta Formation of Mongolia in 1923 during a paleontological expedition led by Roy Chapman Andrews, and in the following year the genus and type species Oviraptor philoceratops were named by Henry Fairfield Osborn. The genus name refers to the initial thought of egg-stealing habits, and the specific name was intended to reinforce this view indicating a preference over ceratopsian eggs. Despite the fact that numerous specimens have been referred t
Abelisaurus
Abelisaurus (; "Abel's lizard") is a genus of predatory abelisaurid theropod dinosaur which lived during the Late Cretaceous Period (Campanian) of what is now South America. It was a bipedal carnivore that probably reached about in length, although this is uncertain as it is known from only one partial skull.
Styracosaurus
Styracosaurus ( ; meaning "spiked lizard" from the Ancient Greek / "spike at the butt-end of a spear-shaft" and / "lizard") is an extinct genus of herbivorous dinosaur from the Late Cretaceous (Campanian stage) of North America. It had four to six long parietal spikes extending from its neck frill, a smaller jugal horn on each of its cheeks, and a single horn protruding from its nose, which may have been up to long and wide. The function or functions of the horns and frills have been debated for many years.
Troodon
Troodon ( ; Troödon in older sources) is a controversial genus of relatively small, bird-like theropod dinosaurs definitively known from the Campanian age of the Late Cretaceous period (about 77 million years ago). 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.
Protoceratops
Protoceratops (; ) is a genus of small protoceratopsid dinosaurs that lived in Asia during the Late Cretaceous, around 75 to 71 million years ago. The genus Protoceratops includes two species: P. andrewsi and the larger P. hellenikorhinus. The former was described in 1923 with fossils from the Mongolian Djadokhta Formation, and the latter in 2001 with fossils from the Chinese Bayan Mandahu Formation. Protoceratops was initially believed to be an ancestor of ankylosaurians and larger ceratopsians, such as Triceratops and relatives, until the discoveries of other protoceratopsids. Populations of
Euoplocephalus
Euoplocephalus ( ) is a genus of large herbivorous ankylosaurid dinosaurs, living during the Late Cretaceous of Canada. It has only one named species, Euoplocephalus tutus.
Corythosaurus
Corythosaurus (; ) is a genus of hadrosaurid "duck-billed" dinosaur from the Late Cretaceous period, about 77–75.7 million years ago, in what is now western North America. Its name is derived from the Greek word κόρυς, meaning "helmet", named and described in 1914 by Barnum Brown. Corythosaurus is now thought to be a lambeosaurine, thus related to Lambeosaurus, Nipponosaurus, Velafrons, Hypacrosaurus, and Olorotitan. Corythosaurus has an estimated length of and has a skull, including the crest, that is tall.
Gordosaurus
Gorgosaurus ( ; ) is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period (Campanian), between about 76.5 and 75 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.
Ornithomimus
Ornithomimus (; "bird mimic") is a genus of ornithomimid theropod dinosaurs from the Campanian and Maastrichtian ages of the Late Cretaceous in western North America. Ornithomimus was a swift, bipedal dinosaur which was covered in feathers and 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.
Lambeosaurus
Lambeosaurus ( ) is a genus of hadrosaurid dinosaur that lived during the Late Cretaceous period of western North America. The first skull of Lambeosaurus found was used by palaeontologist Lawrence M. Lambe to justify the creation of the new genus Stephanosaurus, although it was not part of the latter's original material. Its incomplete nature led William A. Parks to name Lambeosaurus lambei for this skull in 1923 to honour Lambe. Multiple species of Lambeosaurus have been named since, including L. clavinitialis and L. magnicristatus in 1935, and L. laticaudus in 1981 which was later moved to
Maiasaura
Maiasaura (from , and , the feminine form of saurus, ) is a large herbivorous saurolophine hadrosaurid ("duck-billed") dinosaur genus that lived in the area currently covered by the state of Montana and the Canadian province of Alberta, in the Upper Cretaceous (mid to late Campanian), from 86.3 to 70.6 million years ago. Maiasaura is the state fossil of Montana.
Daspletosaurus
Daspletosaurus ( ; meaning "frightful lizard") is a genus of tyrannosaurid dinosaur that lived in Laramidia between about 77 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 in Montana and Alberta. D. wilsoni has been suggested as an intermediate species between D. torosus and D. horneri that evolved through anagenesis, though further research may be required to definitively support the th
Pachyrhinosaurus
Pachyrhinosaurus (from Ancient Greek ' (), thick; ' (), nose; and (), lizard) is a genus of centrosaurine ceratopsid dinosaur from the Late Cretaceous period of North America. The first examples were discovered by Charles M. Sternberg in Alberta, Canada, in 1946, and named in 1950. Over a dozen partial skulls and a large assortment of other fossils from various species have been found in Alberta and Alaska. A great number were not available for study until the 1980s, resulting in a relatively recent increase of interest in Pachyrhinosaurus.
Struthiomimus
Struthiomimus (meaning "ostrich mimic", from the Ancient Greek στρούθειος/stroutheios, meaning "of the ostrich", and μῖμος/mimos, meaning "mimic" or "imitator") is a genus of ornithomimid dinosaurs from the Late Cretaceous of what is now western North America. They were long-legged, bipedal, ostrich-like dinosaurs with toothless beaks. The type species, Struthiomimus altus, is one of the more common, smaller dinosaurs found in Dinosaur Provincial Park. Their overall abundance, in addition to their toothless beak, suggests that these animals were mainly herbivorous or (more likely) omnivorous,
Edmontonia
Edmontonia is a genus of panoplosaurin nodosaurid dinosaur from the Late Cretaceous Period of what is now western North America. It is named after the Edmonton Formation (now the Horseshoe Canyon Formation in Canada), the unit of rocks where it was first found.
Dromaeosaurus
Dromaeosaurus (; ) is a genus of dromaeosaurid theropod dinosaur that lived during the Late Cretaceous period (middle to late Campanian and Maastrichtian), sometime between 80 and 69 million years ago, in the Canadian province of Alberta 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 t
Centrosaurus
Centrosaurus ( ; ) is a genus of centrosaurine ceratopsid dinosaur from the Campanian age of the Late Cretaceous of Canada. Its remains have been found in the Dinosaur Park Formation, dating from 76.5 to 75.5 million years ago. The type and only species seen as valid today is Centrosaurus apertus.
Shantungosaurus
Shantungosaurus () is an extinct genus of very large herbivorous saurolophine hadrosaurid dinosaur found in the Late Cretaceous Wangshi Group of the Shandong Peninsula in China, containing a single species, Shantungosaurus giganteus. The stratigraphic interval of Shantungosaurus ranges from the top of the Xingezhuang Formation to the middle of the Hongtuya Formation, middle to late Campanian in age. Shantungosaurus is so far the largest hadrosauroid taxon in the world, with size estimates around in length and in body mass.
Chasmosaurus
Chasmosaurus ( ) is a genus of ceratopsid dinosaur from the Late Cretaceous Period in North America. Its given name means 'opening lizard', referring to the large openings (fenestrae) in its frill (Greek chasma, meaning 'opening', 'hollow', or 'gulf'; and sauros, meaning 'lizard'). With a length of and a weight of —or anywhere from 2,200 to nearly 5,000 lbs—Chasmosaurus was of a slightly smaller to "average" size, especially when compared to larger ceratopsids (such as Triceratops, which were about the size of an African bush elephant).
Bambiraptor
Bambiraptor is a genus of bird-like dromaeosaurid theropod dinosaur that lived during the Late Cretaceous (about 72 million years ago) of Montana. It was described by scientists at the University of Kansas, Yale University, and the University of New Orleans. The holotype fossil is less than long, although this specimen appears to be a juvenile, and it is possible that Bambiraptor is a juvenile Saurornitholestes. It is even suspected that the type specimen is a chimera, based on the fact that "there are elements of three different similarly sized lower legs included in the holotype." Because of
Bagaceratops rozhdestvenskyi
Bagaceratops (meaning "small-horned face") is a genus of small protoceratopsid dinosaurs that lived in Asia during the Late Cretaceous, around 72 to 71 million years ago. Bagaceratops remains have been reported from the Barun Goyot Formation and Bayan Mandahu Formation. One specimen may argue the possible presence of Bagaceratops in the Djadochta Formation.
Hadrosaurus
Hadrosaurus (; ) is a genus of hadrosaurid ornithopod dinosaurs that lived in North America during the Late Cretaceous Period in what is now the Woodbury Formation in New Jersey about 83.6 to 77.9 million years ago. The holotype specimen was found in fluvial marine sedimentation, meaning that the corpse of the animal was transported by a river and washed out to sea. Some fossils are found in the Tar Heel/Coachman Formation.
Saurornithoides
Saurornithoides ( ) is a genus of troodontid maniraptoran dinosaur, which lived during the Late Cretaceous period. These creatures were predators, which could run fast on their hind legs and had excellent sight and hearing. The name is derived from the Greek stems saur~ (lizard), ornith~ (bird) and eides (form), referring to its bird-like skull.
Achelousaurus
Achelousaurus () is a genus of centrosaurine ceratopsid dinosaur that lived during the Late Cretaceous Period of what is now North America, about 77 to 74.8 million years ago. The first fossils of Achelousaurus were collected in Montana in 1987, by a team led by Jack Horner, with more finds made in 1989. In 1994, Achelousaurus horneri was described and named by Scott D. Sampson; the generic name means "Achelous lizard", in reference to the Greek deity Achelous, and the specific name refers to Horner. The genus is known from a few specimens consisting mainly of skull material from individu
Stegoceras
Stegoceras is a genus of pachycephalosaurid (dome-headed) dinosaur that lived in what is now North America during the Late Cretaceous period, about 77.5 to 74 million years ago (mya). The first specimens from Alberta, Canada, were described in 1902, and the type species Stegoceras validum was based on these remains. The generic name means "horn roof", and the specific name means "strong". Several other species have been placed in the genus over the years, but these have since been moved to other genera or deemed junior synonyms. Currently only S. validum and S. novomexicanum, named in 2011 fro
Pentaceratops
Pentaceratops ("five-horned face") is a genus of herbivorous ceratopsid dinosaur from the late Cretaceous Period of what is now North America. Fossils of this animal were first discovered in 1921, but the genus was named in 1923 when its type species, Pentaceratops sternbergii, was described. Pentaceratops lived around 76–73 million years ago, its remains having been mostly found in the Kirtland Formation in the San Juan Basin in New Mexico. Another species, P. aquilonius, was named by Nick W. Longrich in 2014, but it is debated if it belongs to that genus or a separate taxon. About a dozen sk
Tsintaosaurus
Tsintaosaurus (; sic for the old transliteration "Tsingtao", meaning "Qingdao lizard") is a genus of hadrosaurid dinosaur from the Late Cretaceous of China. It was about long and weighed . The type species is Tsintaosaurus spinorhinus, first described by Chinese paleontologist C. C. Young in 1958. As a hadrosaur, Tsintaosaurus had the characteristic 'duck bill' snout and a battery of powerful teeth which it used to chew vegetation. It usually walked on all fours, but could rear up on its hind legs to scout for predators and flee when it spotted one. Like other hadrosaurs, Tsintaosaurus probabl
Lythronax
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 geograph
Aerosteon
Aerosteon is a genus of megaraptoran dinosaur from the Late Cretaceous period of Argentina. Its remains were discovered in 1996 in the Anacleto Formation, which is from the late Campanian. The type and only known species is A. riocoloradensis. Its generic name can be translated as "air bone" and derives from Greek ἀήρ (aer, "air") and ὀστέον (osteon, "bone"), whereas its specific name indicates that its remains were found 1 km (0.6 miles) north of the Río Colorado, in Mendoza Province, Argentina. The genus shows evidence of a bird-like respiratory system.
Sinoceratops
Sinoceratops is an extinct genus of ceratopsian dinosaur that lived from 77.3 to 73.5 million years ago during the latter part of the Cretaceous Period in what is now Shandong province in China. It was named in 2010 by Xu Xing et al. for three skulls from Zhucheng, China. The name of the type species Sinoceratops zhuchengensis means "Chinese horned face from Zhucheng", after the location of its discovery. Sinoceratops was a medium-sized, averagely-built, ground-dwelling, quadrupedal herbivore. It could grow up to an estimated in length and weigh up to .
Aeolosaurus
Aeolosaurus (; "Aeolus' lizard") is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. Like most sauropods, it would have been a quadrupedal herbivore with a long neck and tail. Aeolosaurus is well known for a titanosaur, as it is represented by the remains of several individuals belonging to at least two species. However, like most titanosaurs, no remains of the skull are known. The holotype of Aeolosaurus rionegrinus consists of a series of seven tail vertebrae, as well as parts of both forelimbs and the right hindlimb. It was discovered
Zhuchengtyrannus
Zhuchengtyrannus (meaning "Zhucheng tyrant") is a genus of tyrannosaurid theropod dinosaur from Asia, 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.
Citipati
Citipati (; meaning "funeral pyre lord") is a genus of oviraptorid dinosaur that lived in Asia during the Late Cretaceous period, about 75 million to 71 million years ago. It is mainly known from the Ukhaa Tolgod locality at the Djadochta Formation, where the first remains were collected during the 1990s. The genus and type species Citipati osmolskae were named and described in 2001. A second species from the adjacent Zamyn Khondt locality may also exist. Citipati is one of the best-known oviraptorids thanks to a number of well-preserved specimens, including individuals found in brooding posit
Shuvuuia
Shuvuuia is a genus of bird-like theropod dinosaur from the late Cretaceous period of Mongolia. It is a member of the family Alvarezsauridae, small coelurosaurian dinosaurs which are characterized by short but powerful forelimbs specialized for digging. The type (and only known) species is Shuvuuia deserti, or "desert bird". The name Shuvuuia is derived from the Mongolian word shuvuu (шувуу) meaning "bird".
Gryposaurus
Gryposaurus (meaning "hooked-nosed (Greek grypos) lizard"; sometimes incorrectly translated as "griffin (Latin gryphus) lizard") was a genus of duckbilled dinosaur that lived about 80 to 75 million years ago, in the Late Cretaceous (late Santonian to late Campanian stages) of North America. Named species of Gryposaurus are known from the Dinosaur Park Formation in Alberta, Canada, and two formations in the United States: the Lower Two Medicine Formation in Montana and the Kaiparowits Formation of Utah. A possible additional species from the Javelina Formation in Texas may extend the temporal r
Dreadnoughtus
Dreadnoughtus is a genus of titanosaurian sauropod dinosaur containing a single species, Dreadnoughtus schrani. It is known from two partial skeletons discovered in Upper Cretaceous (Campanian to Maastrichtian, approximately 76–70 million years ago) rocks of the Cerro Fortaleza Formation in Santa Cruz Province, Argentina. It is one of the largest terrestrial vertebrates known from reasonably complete remains, with the immature type specimen measuring in total body length and weighing up to 48–49 metric tons (53–54 short tons).
Einiosaurus
Einiosaurus is a genus of herbivorous centrosaurine ceratopsian dinosaur from the Upper Cretaceous (Campanian stage) of northwestern Montana. The name means 'bison lizard', in a combination of Blackfeet Indian eini and Latinized Ancient Greek sauros; the specific name (procurvicornis) means 'with a forward-curving horn' in Latin. Einiosaurus is medium-sized with an estimated body length at .
Agujaceratops
Agujaceratops (meaning "horned face from Aguja") is a genus of chasmosaurine ceratopsid dinosaur from the Late Cretaceous (Campanian) of western Texas. Two species are known: A. mariscalensis and A. mavericus, both recovered from the Aguja Formation.
Panoplosaurus
Panoplosaurus is a genus of armoured dinosaur from the Late Cretaceous of Alberta, Canada. Few specimens of the genus are known, all from the middle Campanian of the Dinosaur Park Formation, roughly 76 to 75 million years ago. It was first discovered in 1917, and named in 1919 by Lawrence Lambe, named for its extensive armour, meaning "well-armoured lizard". Panoplosaurus has at times been considered the proper name for material otherwise referred to as Edmontonia, complicating its phylogenetic and ecological interpretations, at one point being considered to have existed across Alberta, New Me
Pinacosaurus
Pinacosaurus (meaning "Plank lizard") is a genus of ankylosaurid thyreophoran dinosaur that lived in Asia during the Late Cretaceous (Campanian, roughly 75 to 71 million years ago), mainly in Mongolia and China.
Monoclonius
Monoclonius (meaning "single sprout") is an extinct dubious genus of herbivorous ceratopsian dinosaur found in the Late Cretaceous layers of the Judith River Formation in Montana, United States, and the uppermost rock layers of the Dinosaur Park Formation in Alberta, Canada dated to between 75 and 74.6 million years ago.
Kritosaurus
Kritosaurus is an incompletely known genus of hadrosaurid (duck-billed) dinosaur. It lived about 74.5-66 million years ago, in the Late Cretaceous of North America. The name means "separated lizard" (referring to the arrangement of the cheek bones in an incomplete type skull), but is often mistranslated as "noble lizard" in reference to the presumed "Roman nose" (in the original specimen, the nasal region was fragmented and disarticulated, and was originally restored flat).
Saichania
Saichania (Mongolian meaning "beautiful one") is a genus of herbivorous ankylosaurid dinosaur from the Late Cretaceous period of Mongolia and China. The first fossils of Saichania were found in the early 1970s in the Baruungoyot Formation. In 1977, the type species Saichania chulsanensis was named.
Austroraptor
Austroraptor ( ) is a genus of unenlagiine theropod dinosaur that lived during the Campanian and Maastrichtian ages of the Late Cretaceous period in what is now Argentina.
Adamantisaurus
Adamantisaurus ( ) is a poorly-known genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. It is only known from six tail vertebrae but, as a sauropod, it can be assumed that this dinosaur was a very large animal with a long neck and tail. thumb|Sculpture of Adamantisaurus
Micropachycephalosaurus
Micropachycephalosaurus (meaning "small thick-headed lizard") is an extinct genus of basal marginocephalian dinosaur, containing only the type species, Micropachycephalosaurus hongtuyanensis. It lived in China during the Late Cretaceous (Campanian) and was found in the Jiangjunding Formation. It has the longest name of any dinosaur, with 23 letters in the genus name alone, while the full binomial contains 37 letters.
Prosaurolophus
Prosaurolophus (; meaning "before Saurolophus", in comparison to the later dinosaur with a similar head crest) is a genus of hadrosaurid (or duck-billed) dinosaur from the Late Cretaceous of North America. It is known from the remains of at least 25 individuals, including skulls and skeletons, but this remains obscure. Its fossils have been found in the late Campanian-aged Dinosaur Park Formation in Alberta, and the roughly contemporaneous Two Medicine Formation in Montana, dating to around 75.7 to 74.1 million years ago. Its most recognizable feature is a small solid crest formed by the nasal
Teratophoneus
Teratophoneus ("monstrous murderer"; Greek: teras, "monster" and phoneus, "murderer") is a genus of tyrannosaurine theropod dinosaur that lived during the late Campanian age of the Late Cretaceous period, (about 76.5 to 75.5 million years ago) in what is now Utah. It contains a single known species, T. curriei, named in honor of paleontologist Philip J. Currie. It is known from an incomplete skull and postcranial skeleton recovered from the Kaiparowits Formation.
Kosmoceratops
Kosmoceratops () is a genus of ceratopsid dinosaur that lived in North America about 76–75.9 million years ago during the Late Cretaceous period. Specimens were discovered in Utah in the Kaiparowits Formation of the Grand Staircase–Escalante National Monument in 2006 and 2007, including an adult skull and postcranial skeleton and partial subadults. In 2010, the adult was made the holotype of the new genus and species Kosmoceratops richardsoni; the generic name means "ornate horned face", and the specific name honors Scott Richardson, who found the specimens. The find was part of a spate of cer
Saurornitholestes
Saurornitholestes ("lizard-bird thief") is a genus of carnivorous dromaeosaurid theropod dinosaur from the late Cretaceous of Canada (Alberta and Saskatchewan) and the United States (Montana, New Mexico, Alabama, and South Carolina). Two species have been named that are regarded as valid: Saurornitholestes langstoni in 1978 and Saurornitholestes sullivani in 2015. Saurornitholestes was a small, bipedal, meat-eating dinosaur, equipped with a sickle-like claw on each foot.
Byronosaurus
Byronosaurus is a genus of troodontid dinosaur from the Late Cretaceous Period of Mongolia.
Chirostenotes
Chirostenotes ( ; named from Greek 'narrow-handed') is a genus of oviraptorosaurian dinosaur from the late Cretaceous (about 76.5–75 million years ago) of Alberta, Canada. The type species is Chirostenotes pergracilis.
Tarchia
Tarchia (meaning "brainy one") is a genus of herbivorous ankylosaurid dinosaur from the late Cretaceous of Mongolia.
Orodromeus
thumb|Reconstruction of the Orodromeus skeleton
Bistahieversor
Bistahieversor (meaning "Bistahi destroyer"), 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.
Mahakala
genus of reptiles (fossil)
Halszkaraptor
Halszkaraptor (; meaning "Halszka's seizer") is a genus of waterfowl-like dromaeosaurid dinosaurs from Mongolia that lived during the Late Cretaceous period. It contains only one known species, Halszkaraptor escuilliei.
Avaceratops
Avaceratops is a genus of small herbivorous ceratopsian dinosaurs which lived during the late Campanian in what are now the Northwest United States. Most fossils come from the Judith River Formation.