Morrison Formation

Stegosaurus (; ) is a genus of herbivorous four-legged armored dinosaurs from the Late Jurassic, characterized by the distinctive kite-shaped upright plates along their backs and spikes on their tails. Fossils of the genus have been found in the western United States and in Portugal, where they are found in Kimmeridgian- to Tithonian-aged strata, dating to between 155 and 145 million years ago. Of the species that have been classified in the upper Morrison Formation of the western US, only three are universally recognized: S. stenops, S. ungulatus and S. sulcatus. The remains of over 80 i

Diplodocus (, , or ) is an extinct genus of diplodocid sauropod dinosaurs known from the Late Jurassic of North America. The first fossils of Diplodocus were discovered in 1877 by S. W. Williston. The generic name, coined by Othniel Charles Marsh in 1878, is a Neo-Latin term derived from Greek διπλός (diplos) "double" and δοκός (dokos) "beam", in reference to the double-beamed chevron bones located in the underside of the tail, which were then considered unique.

Brachiosaurus () is a genus of sauropod dinosaur that lived in North America during the Late Jurassic, about 155.6 to 145.5 million years ago. It was first described by American paleontologist Elmer S. Riggs in 1903 from fossils found in the Colorado River valley in western Colorado, United States. Riggs named the dinosaur Brachiosaurus altithorax; the generic name is Greek for "arm lizard", in reference to its proportionately long arms, and the specific name means "deep chest". Brachiosaurus is estimated to have been between long; body mass estimates of the subadult holotype specimen range fr

Apatosaurus (; meaning "deceptive lizard") is a genus of herbivorous sauropod dinosaur that lived in North America during the Late Jurassic period. Othniel Charles Marsh described and named the first-known species, Apatosaurus ajax, in 1877, and a second species, Apatosaurus louisae, was discovered and named by William H. Holland in 1916. Apatosaurus lived about 152 to 151 million years ago (mya), during the late Kimmeridgian to early Tithonian age, and are now known from fossils in the Morrison Formation of modern-day Colorado, Oklahoma, New Mexico, Wyoming, and Utah in the United States. Apa

Allosaurus ( ) is a genus of theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic period (Kimmeridgian to late Tithonian ages). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by Othniel C. Marsh. The name "Allosaurus" means "different lizard", alluding to its lightweight , which Marsh believed were unique. The genus has a very complicated taxonomy and includes at least three valid species, the best known of which is A. fragilis. The bulk of Allosaurus remains come from North America's Morrison Formation, with mate

Ceratosaurus (from Greek 'horn' and 'lizard') is a genus of carnivorous theropod dinosaur that lived during the Late Jurassic period in North America and Europe. The genus was first described in 1884 by American paleontologist Othniel Charles Marsh based on a nearly complete skeleton discovered in Garden Park, Colorado, in rocks belonging to the Morrison Formation. The type species is Ceratosaurus nasicornis.

Barosaurus ( ) is an extinct genus of giant, long-tailed, long-necked, plant-eating sauropod dinosaur closely related to the more familiar Diplodocus. Definitive remains have been found in the Morrison Formation from the Upper Jurassic Period of South Dakota, Utah and Montana, with other possible remains also found in Colorado, eastern Wyoming and Oklahoma. The generic name, Barosaurus, comes from the Greek words barys (βαρυς) meaning "heavy" and sauros (σαυρος) meaning "lizard", and thus meaning "heavy lizard".

Camarasaurus ( ) is a genus of sauropod dinosaur that lived during the Late Jurassic in what is now the United States. Its fossils are primarily known from the Morrison Formation dating to the Kimmeridgian and Tithonian ages of the Jurassic, between 155 and 145 million years ago (mya). It was named by Edward Drinker Cope in 1877; it definitively contains three species, C. supremus, the type species, C. grandis, and C. lentus, while some researchers consider C. lewisi to be in its own genus, Cathetosaurus. The generic name means "chambered lizard", referring to the hollow chambers, known as ple

Camptosaurus ( ) is an extinct genus of plant-eating, beaked ornithischian dinosaurs of the Late Jurassic period of western North America and possibly also Europe. The name means 'flexible lizard' (Greek ('''') meaning 'bent' and ('''') meaning 'lizard').

Brontosaurus (; meaning "thunder lizard" from the Greek words , "thunder" and , "lizard") is a genus of herbivorous sauropod dinosaur that lived in present-day United States during the Late Jurassic period. It was described by American paleontologist Othniel Charles Marsh in 1879, the type species being dubbed B. excelsus, based on a partial skeleton lacking a skull found in Como Bluff, Wyoming. In subsequent years, two more species of Brontosaurus were named: B. parvus in 1902 and B. yahnahpin in 1994. Brontosaurus lived about 156 to 146 million years ago (mya) during the Kimmeridgian and Tit

Supersaurus (meaning "super lizard") is a genus of diplodocid sauropod dinosaur that lived in North America during the Late Jurassic period. The type species, S. vivianae, was first discovered by Vivian Jones of Delta, Colorado, in the middle Morrison Formation of Colorado in 1972. The fossil remains came from the Brushy Basin Member of the formation, dating between 153 and 145 million years ago. It is among the longest dinosaurs ever discovered, with the three known specimens reaching in length, with the largest individual possibly exceeding in size. Mass estimates for the WDC and BYU specime

Torvosaurus () is a genus of large megalosaurine theropod dinosaur that lived approximately 165 to 146.5 million years ago during the Callovian to Tithonian ages of the late Middle and Late Jurassic period in what is now Colorado, Portugal, Germany, and possibly England, Spain, Tanzania, and Uruguay. It contains two currently recognized species, Torvosaurus tanneri and Torvosaurus gurneyi, plus a third unnamed species from Germany.

Amphicoelias (, meaning "biconcave", from the Greek ἀμφί, amphi: "on both sides", and κοῖλος, koilos: "hollow, concave") is a genus of herbivorous sauropod dinosaur that lived approximately 150 million years ago during the Tithonian (Late Jurassic Period) of what is now Colorado, United States. Amphicoelias was moderately sized at about in length and in body mass, shorter than its close relative Diplodocus. Its hindlimbs were very long and thin, and its forelimbs were proportionally longer than in relatives.

Ornitholestes (from Ancient Greek ὄρνις (órnis), meaning "bird", and λῃστής (lēistḗs), meaning "robber", and thus, "bird robber") is a small theropod dinosaur of the late Jurassic (Brushy Basin Member of the Morrison Formation, middle Kimmeridgian age, about 154 million years ago) of Western Laurasia (the area that was to become North America).

Dryosaurus ( , meaning 'tree lizard', Greek '''' () meaning 'tree, oak' and () meaning 'lizard' (the name reflects the forested habitat, not a vague oak-leaf shape of its cheek teeth as is sometimes assumed)) is an extinct genus of herbivorous ornithopod dinosaur that lived in the Late Jurassic period. It was an iguanodont (formerly classified as a hypsilophodont). Fossils have been found in the western United States and were first discovered in the late 19th century. Valdosaurus canaliculatus and Dysalotosaurus lettowvorbecki were both formerly considered to represent species of Dryosaurus.

Saurophaganax ("lord of lizard-eaters") is a dubious, chimeric genus of large saurischian dinosaur, possibly a sauropod, from the Late Jurassic (Kimmeridgian) Morrison Formation of Oklahoma, United States. This taxon was historically considered to represent a species of Allosaurus or very large allosaurid. However, re-examinations of the attributed specimens suggested that it is a chimera of multiple dinosaur genera, since some specimens most likely belong to a diplodocid sauropod, while the other referred specimens could be reassigned to a novel species of Allosaurus.

period of competitive fossil hunting during the Gilded Age of American history, marked by a heated rivalry between Edward Drinker Cope and Othniel Charles Marsh

Coelurus is a genus of coelurosaurian dinosaur from the Late Jurassic period (mid-late Kimmeridgian faunal stage, 155–152 million years ago). The name means "hollow tail", referring to its hollow tail vertebrae (Greek κοῖλος, koilos = hollow + οὐρά, oura = tail). Although its name is linked to one of the main divisions of theropods (Coelurosauria), it has historically been poorly understood, and sometimes confused with its better-known contemporary Ornitholestes. Like many dinosaurs studied in the early years of paleontology, it has had a confusing taxonomic history, with several species

Hesperosaurus (from Ancient Greek ἕσπερος (hésperos), meaning "western", and σαῦρος (saûros), meaning "lizard") is a herbivorous stegosaurian dinosaur from the Kimmeridgian age of the Jurassic period, approximately 156 million years ago.

Haplocanthosaurus (meaning "simple spined lizard") is a genus of diplodocoid sauropod dinosaur. Two species, H. delfsi and H. priscus, are known from incomplete fossil skeletons. They lived during the Late Jurassic (Kimmeridgian stage), 155 to 152 million years ago in North America. The type species is H. priscus, named in 1903 John Bell Hatcher , and the referred species H. delfsi was discovered by a young college student named Edwin Delfs in Colorado, United States and described by Jack McIntosh and Michael Williams in 1988. Haplocanthosaurus specimens have been found in the lowermost layer

Rock formation

REDIRECT Taxonomy of Allosaurus#Epanterias amplexus

Stokesosaurus (meaning "Stokes' lizard") is a genus of early tyrannosauroid theropod dinosaurs from the late Jurassic period of Utah, United States. They were small, bipedal predators measuring around in length.

thumb|Comparison of Maraapunisaurus (left) with the rebbachisaurids Rebbachisaurus (center) and Histriasaurus (right). thumb|Neural spine of Maraapunisaurus as drawn by E.D. Cope with parts labeled. The key rebbachisaurid features are the spinopostzygapophyseal laminae that extends dorsomedially from the postzygapophyses to join and form the postspinal lamina, and the pneumatic neural spine and arch. Other rebbachisaurid features include the rather simple ("attenuated") structure of the neural spine and the respective inclinations of the centrodiapophyseal lamina and the postzygodiapophyseal l

Gargoyleosaurus (meaning "gargoyle lizard") is one of the earliest ankylosaurs known from reasonably complete fossil remains. The holotype was discovered in 1995 at the Bone Cabin Quarry West locality, in Albany County, Wyoming in exposures of the Upper Jurassic (Kimmeridgian to Tithonian stages) Morrison Formation.

Fruitadens is a genus of heterodontosaurid dinosaur. The name means "Fruita teeth", in reference to Fruita, Colorado (USA), where its fossils were first found. It is known from partial skulls and skeletons from at least four individuals of differing biological ages, found in Tithonian (Late Jurassic) rocks of the Morrison Formation in Colorado. Fruitadens is one of the smallest known ornithischian dinosaur, with young adults estimated at in length and in weight. It is interpreted as an omnivore and represents one of the latest-surviving heterodontosaurids.

Marshosaurus is a genus of carnivorous theropod dinosaur, belonging to the family Piatnitzkysauridae, from the Late Jurassic Morrison Formation of Utah and possibly Colorado.

Antrodemus ("chamber bodied") is a dubious genus of theropod dinosaur from the Upper Jurassic, probably the Morrison Formation, of Middle Park, Colorado. It contains one species, Antrodemus valens, first described and named as a species of Poekilopleuron by Joseph Leidy in 1870.

national monument in Uintah County, Utah and Moffat County, Colorado in the United States

Tanycolagreus is a genus of coelurosaurian theropod dinosaur from the Late Jurassic (Kimmeridgian to Tithonian) of the U.S. states of Wyoming, Utah, and Colorado.

Mymoorapelta (Meaning "Shield from the Mygatt-Moore Quarry" after a combination of the names of the discoverers of the Mygatt-Moore Quarry that fossils were originally collected from, and the Greek word πέλτα, meaning "shield") is a nodosaurid ankylosaur from the Late Jurassic (Kimmeridgian-Tithonian, around 155 to 150 million years ago) Morrison Formation (Brushy Basin Member) of western Colorado and central Utah, USA. The animal is known from a single species, Mymoorapelta maysi, and few specimens are known. The most complete specimen is the holotype individual from the Mygatt-Moore Quarry,

Nanosaurus ("small or dwarf lizard") is an extinct genus of neornithischian dinosaur that lived about 155 to 148 million years ago, during the Late Jurassic in North America. Its fossils are known from the Morrison Formation of the south-western United States. The type and only species, Nanosaurus agilis, was described and named by Othniel Charles Marsh in 1877. The taxon has a complicated taxonomic history, largely the work of Marsh and Peter M. Galton, involving the genera Laosaurus, Hallopus, Drinker, Othnielia, and Othnielosaurus, the latter three now being considered to be synonyms of Nan

Atlantosaurus (meaning "Atlas lizard") is a dubious genus of sauropod dinosaur. It contains a single species, Atlantosaurus montanus, from the Late Jurassic upper Morrison Formation of Colorado, United States. Atlantosaurus was the first sauropod to be described during the infamous 19th century Bone Wars, during which scientific methodology suffered in favor of pursuit of academic acclaim.

Galeamopus is a genus of herbivorous diplodocid sauropod dinosaurs. It contains two known species: Galeamopus hayi, known from the Late Jurassic lower Morrison Formation (Kimmeridgian age, about 155 million years ago) of Wyoming, United States, and Galeamopus pabsti, known from Wyoming and Colorado. The type species is known from one of the well-preserved diplodocid fossils, a nearly complete skeleton with an associated skull.

Kaatedocus is a genus of flagellicaudatan sauropod known from the middle Late Jurassic (Kimmeridgian stage) of northern Wyoming, United States. It is known from well-preserved skull and cervical vertebrae which were collected in the lower part of the Morrison Formation. The type and only species is Kaatedocus siberi, described in 2012 by Emanuel Tschopp and Octávio Mateus.

Alcovasaurus is an extinct genus of herbivorous stegosaurian dinosaurs that lived in the Late Jurassic. It was found in the Morrison Formation of Wyoming, United States. The genus contains a single species, Alcovasaurus longispinus, originally assigned to the genus Stegosaurus. It is likely a member of the Dacentrurinae, and has been referred to the genus Miragaia by some authors.

Suuwassea is a genus of dicraeosaurid sauropod dinosaur found in Upper Jurassic strata of the Morrison Formation, located in southern Carbon County, Montana, United States. The fossil remains were recovered in a series of expeditions during a period spanning the years 1999 and 2000 and were described by J.D. Harris and Peter Dodson in 2004. They consist of a disarticulated but associated partial skeleton, including partial vertebral series and limb bones.

Dyslocosaurus (meaning "hard-to-place lizard") a genus of sauropod dinosaur from the Late Jurassic Period of Wyoming, North America. The holotype or type specimen the genus is based on, AC 663, is part of the collection of the Amherst College Museum of Natural History. It was collected by professor Frederic Brewster Loomis. However, the only available information regarding its provenance is that given on the label: "Lance Creek", a county in east Wyoming. Loomis himself thought that it stemmed from the Lance Formation, dating from the Late Cretaceous (Maastrichtian).

Koparion is a genus of small coelurosaurian theropod dinosaur, from the late Jurassic Period (Kimmeridgian stage), of Utah. It contains the single named species Koparion douglassi which is known only from a single isolated tooth.

Hesperornithoides (meaning "western bird form"; nicknamed "Lori") is a genus of troodontid theropod dinosaur that lived in North America during the Late Jurassic period.

Dystrophaeus is an extinct genus of sauropod dinosaur. Its type and only species is Dystrophaeus viaemalae, named by Edward Drinker Cope in 1877. Its fossils were found in the Tidwell Member of the Morrison Formation of Utah. Due to the fragmentary condition of its only known specimen, the affinities of Dystrophaeus are uncertain, although excavations carried out at the discovery site since 1989 have uncovered more of the original specimen and hold the potential for an improved understanding of the taxon.

Laosaurus (meaning "stone or fossil lizard") is a genus of neornithischian dinosaur. The type species, Laosaurus celer, was first described by O.C. Marsh in 1878 from remains discovered in the Upper Jurassic (Kimmeridgian) Morrison Formation of Wyoming. The validity of this genus is doubtful because it is based on fragmentary fossils. A second species also from the Morrison Formation, L. gracilis, and a species from the Upper Cretaceous Allison Formation of Alberta, Canada, L. minimus, are also considered dubious.

Enigmacursor (meaning "puzzle runner") is an extinct genus of neornithischian dinosaur from the Late Jurassic Morrison Formation of Colorado, United States. The type species is Enigmacursor mollyborthwickae.

Tichosteus (meaning "walled bone") is a genus of herbivorous dinosaur from the Late Jurassic. It is known only from vertebrae recovered from Kimmeridgian rocks in the Morrison Formation, Colorado.

Apatodon is a dubious genus of dinosaur that may have been a theropod. The type, and only species, A. mirus, was named in 1877 by Othniel Charles Marsh. It was found in the Late Jurassic-aged Morrison Formation of Colorado.

Uteodon (meaning "Ute tooth") is a genus of herbivorous iguanodontian dinosaur. It is a basal iguanodontian which lived during the late Jurassic period (Tithonian age) in what is now Uintah County, Utah. It is known from the middle of the Brushy Basin Member, Morrison Formation. The genus was named by Andrew T. McDonald in 2011 and the type species is U. aphanoecetes. ==History== The holotype specimen, CM 11337 (a virtually complete skeleton minus the skull and tail), was assigned to Camptosaurus medius (Marsh, 1894) by Charles W. Gilmore in 1925. When C. medius was synonymised with Camptosaur

Palaeopteryx (meaning "ancient wing") is an extinct genus of dubious paravian theropod dinosaur from the Morrison Formation of Colorado. The type species is P. thomsoni.

Fosterovenator (meaning "Foster's hunter") is a genus of ceratosaur dinosaur known from the Late Jurassic Morrison Formation of Wyoming. The holotype is YPM VP 058267A, B, and C, a tibia with an articulated astragalus. An additional specimen is known, the paratype YPM VP 058267D, a fibula of a larger individual.

Ardetosaurus is an extinct genus of diplodocid sauropod dinosaurs from the Late Jurassic (Kimmeridgian) Morrison Formation of northern Wyoming, United States. The genus contains a single species, Ardetosaurus viator. It was first described in 2024 on the basis of a partial articulated skeleton, including vertebrae from the neck, back, and tail, hip bones, and part of the left hindlimb. The genus is a member of the Diplodocinae, a subfamily of large long-necked dinosaurs with whiplike tails. Ardetosaurus represents one of many distinct sauropod taxa that coexisted in this formation.

Hypsirhophus (meaning "high roof"; often misspelled "Hypsirophus") is a genus of stegosaurian dinosaurs. It contains a single species, Hypsirhophus discurus, which is known only from a fragmentary specimen. The fossil consists of partial vertebrae from the back, three from the tail, and a piece of rib.

species of Camarasaurus (fossil)

Smitanosaurus (meaning "smith lizard") is a genus of dicraeosaurid sauropod dinosaur from the Late Jurassic of Colorado. The genus contains one species, S. agilis, originally assigned to the defunct genus Morosaurus.

Athenar is an extinct genus of dicraeosaurid sauropod dinosaur from the Late Jurassic of Utah, United States. The genus contains a single species, Athenar bermani, which was described by John Whitlock and colleagues in 2025 based on the holotype specimen CM 26552: a and previously ascribed to the genus Diplodocus. The specimen was found in rocks belonging to the Morrison Formation at the Carnegie Quarry at Dinosaur National Monument.