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 78-80 Ma. 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.
Ornithomimosauria are theropod dinosaurs which bore a superficial resemblance to the modern-day ostrich. They were fast, omnivorous or herbivorous dinosaurs from the Cretaceous Period of Laurasia, as well as Africa and possibly Australia. The group first appeared in the Early Cretaceous and persisted until the Late Cretaceous. Primitive members of the group include Nqwebasaurus, Pelecanimimus, Shenzhousaurus, Hexing and Deinocheirus, the arms of which reached 2.4 m (8 feet) in length. More advanced species, members of the family Ornithomimidae, include Gallimimus, Struthiomimus, and Ornithomimus. Some paleontologists, like Paul Sereno, consider the enigmatic alvarezsaurids to be close relatives of the ornithomimosaurs and place them together in the superfamily Ornithomimoidea.
Deinocheirus is a genus of large ornithomimosaur that lived during the Late Cretaceous around 70 million years ago. In 1965, a pair of large arms, shoulder girdles, and a few other bones of a new dinosaur were first discovered in the Nemegt Formation of Mongolia. In 1970, this specimen became the holotype of the only species within the genus, Deinocheirus mirificus; the genus name is Greek for "horrible hand". No further remains were discovered for almost fifty years, and its nature remained a mystery. Two more complete specimens were described in 2014, which shed light on many aspects of the animal. Parts of these new specimens had been looted from Mongolia some years before, but were repatriated in 2014.
Arkansaurus is an extinct genus of ornithomimosaurian theropod dinosaur. It lived during the Albian and Aptian stages of the Early Cretaceous. The type and only species is Arkansaurus fridayi.
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", but is often mistranslated as "noble lizard" in reference to the presumed "Roman nose".
Harpymimus is a basal ornithomimosaurian theropod dinosaur from the Early Cretaceous Period of what is now Mongolia. Unlike later, more derived ornithomimosaurs, Harpymimus still possessed teeth, although they appear to have been restricted to the dentary of the lower jaw.
Ornithomimidae is an extinct family of theropod dinosaurs which bore a superficial resemblance to modern ostriches. Ornithomimids were fast, omnivorous or herbivorous dinosaurs known mainly from the Late Cretaceous Period of Laurasia, though they have also been reported from the Lower Cretaceous Wonthaggi Formation of Australia.
Anasazisaurus is a genus of saurolophine hadrosaurid ("duckbill") ornithopod dinosaur that lived about 74 million years ago, in the Late Cretaceous Period. It was found in the Farmington Member of the Kirtland Formation, in the San Juan Basin of New Mexico, United States. Only a partial skull has been found to date. It was first described as a specimen of Kritosaurus by Jack Horner, and has been intertwined with Kritosaurus since its description. It is known for its short nasal crest, which stuck out above and between its eyes for a short distance.
Naashoibitosaurus is a genus of hadrosaurid dinosaur that lived about 73 million years ago, in the Late Cretaceous, and was found in the Kirtland Formation of the San Juan Basin in New Mexico, United States. Only a partial skeleton has been found to date. It was first described as a specimen of Kritosaurus by Jack Horner, and has been intertwined with Kritosaurus since its description.
Velafrons is a genus of lambeosaurine hadrosaurid dinosaur from the Late Cretaceous of Mexico. It is known from a mostly complete skull and partial skeleton of a juvenile individual, with a bony crest on the forehead. Its fossils were found in the late Campanian-age Cerro del Pueblo Formation, near Rincon Colorado, Coahuila, Mexico. The type specimen is CPC-59, and the type species is V. coahuilensis.
The Cerro del Pueblo Formation is a geological formation in Coahuila, Mexico, whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation. The formation is believed to correlate with the Baculites reesidesi and Baculites jenseni ammonite zones, which dates it to 73.63-72.74 Ma.
Coahuilaceratops is a genus of chasmosaurine ceratopsian dinosaur that lived during the early Maastrichtian age of the Late Cretaceous epoch, about 71.5 to 70.5 million years ago in what is now northern Mexico. It contains a single species, Coahuilaceratops magnacuerna.
Qiupalong is an extinct genus of ornithomimosaurian theropod that was discovered in the Late Cretaceous Qiupa Formation of Henan, China. The genus contains a single species, Q. henanensis, the specific epithet for which was named for the province of Henan. Uniquely, Qiupalong is one of the few Late Cretaceous non-avian dinosaurs known from both Asia and Laramidia. Specimens from Russia and Alberta have been referred to the genus without being assigned to the type species.
Latirhinus is an extinct genus of lambeosaurine hadrosaurid dinosaur from the Late Cretaceous of Mexico. The type species, Latirhinus uitstlani, was named in 2012 on the basis of a partial skeleton from the Campanian-age Cerro del Pueblo Formation. The specific name uitstlani means "southern" in the Náhuatl language of Mexico, a reference to the species' southern occurrence in the Cretaceous landmass Laramidia.
The Olmos Formation is a geologic formation in Mexico. It preserves fossils of plants, hadrosaurs, ceratopsians, tyrannosaurs and the turtle Palauchelys montellanoi dating back to the Cretaceous period.
This timeline of hadrosaur research is a chronological listing of events in the history of paleontology focused on the hadrosauroids, a group of herbivorous ornithopod dinosaurs popularly known as the duck-billed dinosaurs. Scientific research on hadrosaurs began in the 1850s, when Joseph Leidy described the genera Thespesius and Trachodon based on scrappy fossils discovered in the western United States. Just two years later he published a description of the much better-preserved remains of an animal from New Jersey that he named Hadrosaurus.
Yehuecauhceratops is a genus of horned centrosaurine ceratopsid dinosaur from the Late Cretaceous of Coahuila, Mexico. It contains a single species, Y. mudei, described from two partial specimens by Rivera-Sylva et al. in 2016 and formally named by Rivera-Sylva et al. in 2017. It was a small centrosaurine with a body length of 3 metres (9.8 ft), making it smaller than Agujaceratops and Coahuilaceratops, the other two ceratopsids in its environment; the three may have been ecologically segregated. A ridge bearing a single roughened projection near the bottom of the squamosal bone, which probably supported a small horn, allows Yehuecauhceratops to be distinguished from other centrosaurines. Its affinities to nasutoceratopsin centrosaurines, such as Avaceratops and Nasutoceratops, are supported by various morphological similarities to the former.
Adynomosaurus is a genus of lambeosaurine dinosaur from the Late Cretaceous of what is now Catalonia, Spain. First discovered in 2012, it was named in 2019 with the type and only species being Adynomosaurus arcanus. It is only known from scant material, but is distinguished from other hadrosaurs by its weakly developed shoulder blade which would have had underdeveloped musculature, which lends it its scientific name, partially from the Greek word for "weak". Its exact relationships with other hadrosaurs remain unresolved, with it not consistently being recovered as a relative of any other specific genera, though some studies have allied it with Tsintaosaurini or even found it outside of Hadrosauridae. It would have lived as part of a diverse coastal estuary ecosystem, made up of meandering rivers and mud flats. The discovery of Adynomosaurus adds to the very incomplete fossil record of hadrosaurid dinosaurs in the Late Cretaceous of Europe, and it fits into a picture of major ecological turnover that was occurring during the Maastrichtian stage in the region.
Paraxenisaurus is an extinct genus of ornithomimosaurian theropod from the Late Cretaceous Cerro del Pueblo Formation of Coahuila in Mexico. The genus contains a single species, P. normalensis, which is known from a few bones of tail, hips, hands, and feet. The specific epithet was given in honor of the Benemérita Normal School of Coahuila, a teacher training institution, where the fossils were reposited. It is a member of the family Deinocheiridae and is the only member of that clade known from Laramidia.
Tlatolophus is a genus of hadrosaurid dinosaur belonging to the tribe Parasaurolophini. The only species is the type species, Tlatolophus galorum.
