Triceratops is a genus of chasmosaurine ceratopsian dinosaur that lived during the late Maastrichtian age of the Late Cretaceous period, about 68 to 66 million years ago in what is now western North America. It was one of the last-known non-avian dinosaurs and lived until the Cretaceous–Paleogene extinction event 66 million years ago. The name Triceratops, which means 'three-horned face', is derived from the Greek words trí- meaning 'three', kéras meaning 'horn', and ṓps meaning 'face'.
Torosaurus is a genus of herbivorous chasmosaurine ceratopsian dinosaur that lived during the late Maastrichtian age of the Late Cretaceous period, between 68 and 66 million years ago, though it is possible that the species range might extend to as far back as 69 million years ago. Fossils have been discovered across the Western Interior of North America, from as far north as Saskatchewan to as far south as Texas.
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. With a length of 4.3–4.8 metres (14.1–15.7 ft) and a weight of 1.5–2 tonnes —or anywhere from 2,200 to nearly 5,000 lbs., give or take—Chasmosaurus was of a slightly smaller to ‘average’ size, especially when compared to larger ceratopsians.
Ceratopsia or Ceratopia is a group of herbivorous, beaked dinosaurs that thrived in what are now North America, Europe, and Asia, during the Cretaceous Period, although ancestral forms lived earlier, in the Jurassic. The earliest known ceratopsian, Yinlong downsi, lived between 161.2 and 155.7 million years ago. The last ceratopsian species, Triceratops prorsus, became extinct during the Cretaceous–Paleogene extinction event, 66 million years ago.
Pentaceratops 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. About a dozen skulls and skeletons have been uncovered, so anatomical understanding of Pentaceratops is fairly complete. One exceptionally large specimen later became its own genus, Titanoceratops, due to its more derived morphology, similarities to Triceratops, and lack of unique characteristics shared with Pentaceratops.
Nedoceratops is a controversial genus of ceratopsid dinosaur from the Late Cretaceous period Lance Formation of North America. It is known only from a single skull discovered in Wyoming. Its status is the subject of ongoing debate among paleontologists: some authors consider Nedoceratops a valid, distinct taxon, while others consider it to be an unusual specimen of Triceratops.
Alamosaurus is a genus of titanosaurian sauropod dinosaurs containing a single known species, Alamosaurus sanjuanensis, from the Maastrichtian age of the Late Cretaceous period in what is now southwestern North America. It is the only known titanosaur to have inhabited North America after the nearly 30-million year absence of sauropods from the North American fossil record and probably represents an immigrant from South America.
Glyptodontopelta is a monospecific genus of nodosaurid dinosaur from New Mexico that lived during the Late Cretaceous in what is now the Naashoibito member of the Ojo Alamo Formation. The type and only species, Glyptodontopelta mimus, is known from numerous specimens that consist of osteoderms, a dentary, supraorbital and bone fragments. It was named in 2000 by Tracy Ford. Edmontonia australis is a junior synonym of Glyptodontopelta.
The Kirtland Formation is a sedimentary geological formation.
Agujaceratops is a genus of horned dinosaur from the Late Cretaceous (Campanian) of west Texas. It is a chasmosaurine (long-frilled) ceratopsian. Two species are known, Agujaceratops mariscalensis, and A. mavericus.
Chasmosaurinae is a subfamily of ceratopsid dinosaurs. They were one of the most successful groups of herbivores of their time. Chasmosaurines appeared in the early Campanian, and became extinct, along with all other non-avian dinosaurs, during the Cretaceous–Paleogene extinction event. Broadly, the most distinguishing features of chasmosaurines are prominent brow horns and long frills lacking long spines; centrosaurines generally had short brow horns and relatively shorter frills, and often had long spines projecting from their frills.
Eotriceratops is a genus of herbivorous ceratopsian dinosaurs which lived in the area of North America during the late Cretaceous period. The only named species is Eotriceratops xerinsularis.
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.
The Ojo Alamo Formation is a geologic formation in New Mexico spanning the Mesozoic/Cenozoic boundary. Non-avian dinosaur fossils have controversially been identified in beds of this formation dating from after the Cretaceous–Paleogene extinction event, but these have been explained as either misidentification of the beds in question or as reworked fossils, fossils eroded from older beds and redeposited in the younger beds.
Titanoceratops is a controversial genus of herbivorous ceratopsian dinosaur. It was a giant chasmosaurine ceratopsian that lived in the Late Cretaceous period in what is now New Mexico. Titanoceratops was named for its large size, being one of the largest known horned dinosaurs and the type species was named T. ouranos, after Uranus (Ouranos), the father of the Greek titans. It was named in 2011 by Nicholas R. Longrich for a specimen previously referred to Pentaceratops. Longrich believed that unique features found in the skull reveal it to have been a close relative of Triceratops, classified within the subgroup Triceratopsini. However, other researchers have expressed skepticism, and believe "Titanoceratops" to simply be an unusually large, old specimen of Pentaceratops.
Bravoceratops is a genus of large chasmosaurine ceratopsid dinosaur that lived approximately 70 million years ago, and is known from the Late Cretaceous Javelina Formation in what is now Texas, United States.
This timeline of ceratopsian research is a chronological listing of events in the history of paleontology focused on the ceratopsians, a group of herbivorous marginocephalian dinosaurs that evolved parrot-like beaks, bony frills, and, later, spectacular horns. The first scientifically documented ceratopsian fossils were described by Edward Drinker Cope starting in the 1870s; however, the remains were poorly preserved and their true nature was not recognized. Over the next several decades, Cope named several such genera and species. Cope's hated rival, Othniel Charles Marsh, also described ceratopsian remains. In 1887, Marsh mistook a Triceratops horn for one belonging to a new species of prehistoric Bison. Marsh also named the eponymous genus Ceratops in 1888. The next year, he named the most famous ceratopsian, Triceratops horridus. It was the discovery of Triceratops that illuminated the ceratopsian body plan, and he formally named the Ceratopsia in 1890.
Regaliceratops is a monospecific genus of chasmosaurine ceratopsid dinosaur from Alberta, Canada that lived during the Late Cretaceous in what is now the St. Mary River Formation. The type and only species, Regaliceratops peterhewsi, is known only from an adult individual with a nearly complete skull lacking the lower jaw, which was nicknamed "Hellboy". Regaliceratops was named in 2015 by Caleb M. Brown and Donald M. Henderson. Regaliceratops has an estimated length of 5 metres (16 ft) and body mass of 2 metric tons. The skull of Regaliceratops displays features more similar to centrosaurines, which suggests convergent evolution in display morphology in ceratopsids.
Dineobellator is a genus of dromaeosaurid theropod dinosaur that lived in North America during the Late Cretaceous period 68 million years ago. The remains have been found in the Maastrichtian stage of the Naashoibito Member at the Ojo Alamo Formation, New Mexico.
