| Name | Year | Formation | Location | Notes | Images |
|---|
| Abydosaurus | 2010 | Cedar Mountain Formation (Early Cretaceous, Albian) | United States ( Utah) | Had a short domed crest on its skull similar to that of Giraffatitan | |
| Acantholipan | 2018 | Pen Formation (Late Cretaceous, Santonian) | Mexico ( Coahuila) | Known to possess spike-like osteoderms | |
| Achelousaurus | 1994 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Combines long spikes on the top of its frill and a low keratinous boss over its eyes and nose | |
| Acheroraptor | 2013 | Hell Creek Formation (Late Cretaceous, Maastrichtian) | United States ( Montana) | One of the geologically youngest dromaeosaurids | |
| Acristavus | 2011 | Two Medicine Formation, Wahweap Formation (Late Cretaceous, Campanian) | United States ( Montana
Utah) | Uniquely for a hadrosaurid, it lacked any ornamentation on its skull | |
| Acrocanthosaurus | 1950 | Antlers Formation, Arundel Formation, Cloverly Formation, Twin Mountains Formation (Early Cretaceous, Aptian to Albian) | United States ( Maryland
Oklahoma
Texas
Wyoming) | Possessed elongated neural spines that would have supported a low sail or hump in life | |
| Acrotholus | 2013 | Milk River Formation (Late Cretaceous, Santonian) | Canada ( Alberta) | Had a tall, oval-shaped dome | |
| Adelolophus | 2014 | Wahweap Formation (Late Cretaceous, Campanian) | United States ( Utah) | Potentially a close relative of Parasaurolophus [5] | |
| Agujaceratops | 2006 | Aguja Formation (Late Cretaceous, Campanian) | United States ( Texas) | The type species was originally assigned to the genus Chasmosaurus | |
| Ahshislepelta | 2011 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Relatively small compared to other North American ankylosaurs | |
| Ahshislesaurus | 2025 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | The type specimen was originally considered to belong to Kritosaurus but it has been later found to be likely more closely related to Naashoibitosaurus | |
| Ahvaytum | 2025 | Popo Agie Formation (Late Triassic, Carnian) | United States ( Wyoming) | One of the oldest North American dinosaurs | |
| Akainacephalus | 2018 | Kaiparowits Formation (Late Cretaceous, Campanian) | United States ( Utah) | Much of the skeleton is known, including the entirety of the skull | |
| Alamosaurus | 1922 | Ojo Alamo Formation (Late Cretaceous, Maastrichtian) | United States ( New Mexico) | The first titanosaur confirmed to have crossed into North America, possibly representing a relative of South American forms [6] | |
| Alaskacephale | 2006 | Prince Creek Formation (Late Cretaceous, Maastrichtian) | United States ( Alaska) | Had an array of polygonal nodes on its squamosal | |
| Albertaceratops | 2007 | Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Possessed long brow horns and a bony ridge over its nose | |
| Albertadromeus | 2013 | Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | The proportions of its hindlimb suggest a cursorial lifestyle | |
| Albertavenator | 2017 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | Its discovery suggests that the diversity of small dinosaurs may be higher than previously thought | |
| Albertonykus | 2009 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | May have used its specialized forelimbs to dig into tree trunks for feeding on termites [7] | |
| Albertosaurus | 1905 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | Known from more than thirty specimens, twenty-six of which are preserved together [8] | |
| Aletopelta | 2001 | Point Loma Formation (Late Cretaceous, Campanian) | United States ( California) | Would have lived in present-day Mexico. Its fossils were only found in California due to the shifting of tectonic plates | |
| Allosaurus | 1877 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Oklahoma
Utah
Wyoming) | Multiple specimens have been discovered, making it well-known both popularly and scientifically. At least three species are known from the United States, in addition to one described from Portugal | |
| Ampelognathus | 2023 | Lewisville Formation (Late Cretaceous, Cenomanian) | United States ( Texas) | Originally described as a close relative of a clade containing Thescelosaurus and iguanodonts, [9] but it was recovered as a rhabdodontomorph by subsequent research [10] | |
| Amphicoelias | 1878 | Morrison Formation (Late Jurassic, Tithonian) | United States ( Colorado) | Originally believed to date from the Cretaceous | |
| Anasazisaurus | 1993 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | May have been a second species of Kritosaurus [11] | |
| Anchiceratops | 1914 | Horseshoe Canyon Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Had a long, rectangular frill ringed by short, triangular spikes | |
| Anchisaurus | 1885 | Portland Formation (Early Jurassic, Hettangian to Sinemurian) | United States ( Connecticut
Massachusetts) | Some possible remains were originally misidentified as human skeletons [12] | |
| Angulomastacator | 2009 | Aguja Formation (Late Cretaceous, Campanian) | United States ( Texas) | The tip of its jaw was angled 45° at its anterior end, with the tooth row bent to match | |
| Animantarx | 1999 | Cedar Mountain Formation (Early Cretaceous to Late Cretaceous, Albian to Cenomanian) | United States ( Utah) | Its holotype was discovered during a radiological survey of a fossil site. No bones were exposed before it was excavated | |
| Ankylosaurus | 1908 | Ferris Formation, Frenchman Formation, Hell Creek Formation, Lance Formation, Scollard Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta
Saskatchewan)
United States ( Montana
Wyoming) | The largest and most well-known ankylosaur | |
| Anodontosaurus | 1929 | Dinosaur Park Formation, Horseshoe Canyon Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta) | Originally mistakenly believed to have been toothless | |
| Anzu | 2014 | Hell Creek Formation (Late Cretaceous, Maastrichtian) | United States ( Montana
North Dakota
South Dakota) | Large and known from considerably good remains. Preserves evidence of a tall head crest | |
| Apatoraptor | 2016 | Horseshoe Canyon Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Quill knobs preserved on its ulna confirm this genus had wings | |
| Apatosaurus | 1877 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
New Mexico
Oklahoma
Utah
Wyoming) | Had a characteristically robust skeleton compared to other diplodocids | |
| Appalachiosaurus | 2005 | Blufftown Formation?, Demopolis Chalk, Donoho Creek Formation?, Ripley Formation?, Tar Heel/Coachman Formation? (Late Cretaceous, Campanian) | United States ( Alabama
Georgia (U.S. state)?
North Carolina?
South Carolina?) | The most complete theropod known from the eastern side of North America | |
| Aquilarhinus | 2019 | Aguja Formation (Late Cretaceous, Campanian) | United States ( Texas) | May have been a semiaquatic, coastal species that used its unusual, shovel-shaped bill to scoop up vegetation in wet sediment [13] | |
| Aquilops | 2014 | Cloverly Formation (Early Cretaceous, Albian) | United States ( Montana) | May have had a short horn protruding from its upper beak | |
| Ardetosaurus | 2024 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Wyoming) | The holotype specimen was damaged by a museum fire | |
| Arkansaurus | 2018 | Trinity Group (Early Cretaceous, Aptian to Albian) | United States ( Arkansas) | State dinosaur of Arkansas. Its generic name was in use informally even before its formal description | |
| Arrhinoceratops | 1925 | Horseshoe Canyon Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta) | Described as lacking a nasal horn although this is an artifact of preservation | |
| Astrodon | 1865 | Antlers Formation?, Arundel Formation (Early Cretaceous, Albian) | United States ( Maryland
Oklahoma?) | State dinosaur of Maryland | |
| Astrophocaudia | 2012 | Paluxy Formation (Early Cretaceous, Albian) | United States ( Texas) | Known from a single partial skeleton | |
| Athenar | 2025 | Morrison Formation (Late Jurassic, Tithonian) | United States ( Utah) | Originally believed to be a diplodocid | |
| Atlantosaurus | 1877 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Colorado) | Potentially synonymous with Apatosaurus, [14] but a referred species may represent a separate taxon [15] | |
| Atrociraptor | 2004 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | Had a short, deep snout with enlarged teeth | |
| Aublysodon | 1868 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Only known from teeth | |
| Augustynolophus | 2014 | Moreno Formation (Late Cretaceous, Maastrichtian) | United States ( California) | State dinosaur of California. Originally named as a species of Saurolophus | |
| Avaceratops | 1986 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Lacked the fenestrae in its frill, a feature shared only with Triceratops | |
| Bambiraptor | 2000 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Small but well-preserved enough to display its mix of dinosaur- and bird-like features | |
| Barosaurus | 1890 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( South Dakota
Utah) | Similar to Diplodocus but larger and with a longer neck | |
| Bistahieversor | 2010 | Fruitland Formation, Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Analysis of its braincase suggests it behaved like tyrannosaurids despite likely not being a member of that family [16] | |
| Bisticeratops | 2022 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Preserves bite marks from a tyrannosaurid | |
| Borealopelta | 2017 | Clearwater Formation (Early Cretaceous, Albian) | Canada ( Alberta) | So well-preserved that several osteoderms, keratin, pigments and stomach contents are preserved in the positions they would have been in while alive, without flattening or shriveling | |
| Boreonykus | 2015 | Wapiti Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | One of the few dromaeosaurids known from high latitudes | |
| Brachiosaurus | 1903 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Oklahoma
Utah
Wyoming) | A high browser with a tall chest and elongated forelimbs | |
| Brachyceratops | 1914 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Only known from juvenile remains. One specimen has been found to represent a subadult Styracosaurus ovatus | |
| Brachylophosaurus | 1953 | Judith River Formation, Oldman Formation, Wahweap Formation? (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana
Utah?) | Several specimens preserve extensive soft tissue remains | |
| Bravoceratops | 2013 | Javelina Formation (Late Cretaceous, Campanian to Maastrichtian) | United States ( Texas) | Suggested to have had a single small horn on the top of its frill but this may be inaccurate | |
| Brontomerus | 2011 | Cedar Mountain Formation (Early Cretaceous, Aptian to Albian) | United States ( Utah) | Possessed an enlarged ilium which supported powerful leg muscles, which it may have used to kick away predators | |
| Brontosaurus | 1879 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Utah
Wyoming) | Popularly associated with Apatosaurus but a 2015 study found enough differences for it to be classified as a separate genus [15] | |
| Brontotholus | 2025 | Oldman Formation, Two Medicine Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | One of the largest known North American pachycephalosaurs | |
| Caenagnathus | 1940 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | One of the largest known caenagnathids [17] | |
| Camarasaurus | 1877 | Morrison Formation, Summerville Formation? (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
New Mexico?
Oklahoma?
South Dakota?
Utah
Wyoming) | Very common and known from multiple specimens | |
| Camposaurus | 1998 | Bluewater Creek Formation (Late Triassic, Norian) | United States ( Arizona) | Potentially the oldest known neotheropod | |
| Camptosaurus | 1885 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Utah
Wyoming) | May have fed on tough vegetation as evidenced by extensive wear frequently exhibited on its teeth [18] | |
| Caseosaurus | 1998 | Tecovas Formation (Late Triassic, Norian) | United States ( Texas) | Possibly synonymous with Chindesaurus | |
| Cedarosaurus | 1999 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | One specimen preserves over a hundred gastroliths [19] | |
| Cedarpelta | 2001 | Cedar Mountain Formation (Late Cretaceous, Cenomanian to Turonian) | United States ( Utah) | Lacked the extensive cranial ornamentation of later ankylosaurids | |
| Cedrorestes | 2007 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | Known from a partial skeleton. The specific name, crichtoni, honors Michael Crichton, author of Jurassic Park and The Lost World | |
| Centrosaurus | 1904 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Hundreds of individuals have been preserved in a single "mega-bonebed" [20] | |
| Cerasinops | 2007 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Combines features of both Asian and North American basal ceratopsians | |
| Ceratops | 1888 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Although only known from a few bones, this genus is the namesake of the Ceratopsia and the Ceratopsidae | |
| Ceratosaurus | 1884 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Utah
Wyoming) | Possessed a row of osteoderms running down its back | |
| Chasmosaurus | 1914 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Known from multiple remains, including various skulls | |
| Chindesaurus | 1995 | Chinle Formation (Late Triassic, Norian) | United States ( Arizona) | May be a herrerasaur or a close relative of Tawa [21] | |
| Chirostenotes | 1924 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Originally known only from isolated body parts | |
| Cionodon | 1874 | Denver Formation, Judith River Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta)
United States ( Colorado) | Poorly known | |
| Citipes | 2020 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Some specimens were found as stomach contents of Gorgosaurus [22] | |
| Claosaurus | 1890 | Niobrara Formation (Late Cretaceous, Santonian to Campanian) | United States ( Kansas) | Historically conflated with other hadrosaurs | |
| Coahuilaceratops | 2010 | Cerro Huerta Formation (Late Cretaceous, Maastrichtian) | Mexico ( Coahuila) | Possessed brow horns comparable in size to those of Triceratops and Torosaurus | |
| Coahuilasaurus | 2024 | Cerro del Pueblo Formation (Late Cretaceous, Campanian) | Mexico ( Coahuila) | Identified as a specimen of Kritosaurus [23] before receiving its own genus name [24] | |
| Coelophysis | 1889 | Chinle Formation (Late Triassic, Norian) | United States ( Arizona
New Mexico) | Known from over a thousand specimens, making it one of the most well-known early dinosaurs. Some referred species may belong to their own genera | |
| Coelurus | 1879 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Wyoming) | Potentially an early member of the tyrannosauroid lineage [25] | |
| Colepiocephale | 2003 | Foremost Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Originally described as a species of Stegoceras | |
| Convolosaurus | 2019 | Twin Mountains Formation (Early Cretaceous, Aptian) | United States ( Texas) | Before its formal description, it had been informally referred to as the "Proctor Lake hypsilophodontid" | |
| Coronosaurus | 2012 | Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Had irregular masses of small spikes on the very top of its frill | |
| Corythosaurus | 1914 | Dinosaur Park Formation, Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Possessed a semicircular crest which may have been used for vocalization | |
| Crittendenceratops | 2018 | Fort Crittenden Formation (Late Cretaceous, Campanian) | United States ( Arizona) | The youngest known member of the Nasutoceratopsini | |
| Daemonosaurus | 2011 | Chinle Formation (Late Triassic, Norian to Rhaetian?) | United States ( New Mexico) | Unique among early dinosaurs for possessing a short snout with long teeth | |
| Dakotadon | 2008 | Lakota Formation (Early Cretaceous, Valanginian to Barremian) | United States ( South Dakota) | Originally named as a species of Iguanodon | |
| Dakotaraptor | 2015 | Hell Creek Formation (Late Cretaceous, Maastrichtian) | United States ( South Dakota) | The holotype assemblage may represent a chimera of multiple taxa [26] | |
| Daspletosaurus | 1970 | Dinosaur Park Formation, Judith River Formation, Oldman Formation, Two Medicine Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | At least three species are known. These have been interpreted as forming an anagenetic lineage [27] but this hypothesis has been criticized [28] | |
| Deinonychus | 1969 | Antlers Formation, Arundel Formation?, Cedar Mountain Formation?, Cloverly Formation (Early Cretaceous to Late Cretaceous, Aptian to Cenomanian) | United States ( Maryland?
Montana
Oklahoma
Utah?
Wyoming) | Its discovery helped researchers realize that dinosaurs were active, warm-blooded animals, kicking off the Dinosaur Renaissance | |
| Denversaurus | 1988 | Hell Creek Formation, Lance Formation (Late Cretaceous, Maastrichtian) | United States ( South Dakota
Wyoming) | The youngest known nodosaurid [29] | |
| Diabloceratops | 2010 | Wahweap Formation (Late Cretaceous, Campanian) | United States ( Utah) | Had a distinctively short, deep skull | |
| Diclonius | 1876 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Replaced its teeth in such a way that new teeth could be used at the same time as older ones | |
| Dilophosaurus | 1970 | Kayenta Formation (Early Jurassic, Sinemurian to Toarcian) | United States ( Arizona) | Possessed two semicircular crests running along the length of the skull | |
| Dineobellator | 2020 | Ojo Alamo Formation (Late Cretaceous, Maastrichtian) | United States ( New Mexico) | Several features of its hands and feet may be adaptations for increased grip strength [30] | |
| Diplodocus | 1878 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian?) | United States ( Colorado
Montana
New Mexico
Utah
Wyoming) | Had a long, thin tail popularly thought to have been used like a bullwhip [31] but it is possible that it could not handle the stress of supersonic travel [32] | |
| Diplotomodon | 1868 | Hornerstown Formation?/Navesink Formation? (Late Cretaceous, Maastrichtian) | United States ( New Jersey) | Has been suggested to be non-dinosaurian | |
| Dromaeosaurus | 1922 | Dinosaur Park Formation, Hell Creek Formation?, Horseshoe Canyon Formation?, Prince Creek Formation? (Late Cretaceous, Campanian to Maastrichtian?) | Canada ( Alberta)
United States ( Alaska?
South Dakota?) | Analysis of wear on its teeth suggests it preferred tougher prey, including bone | |
| Dromiceiomimus | 1972 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | May be synonymous with Ornithomimus edmontonicus | |
| Dryosaurus | 1894 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Utah
Wyoming) | Remains of multiple growth stages have been found, including specimens in embryonic age [33] | |
| Dryptosaurus | 1877 | Navesink Formation?, New Egypt Formation (Late Cretaceous, Maastrichtian) | United States ( New Jersey) | Its discovery showed that theropods were bipedal animals | |
| Dynamoterror | 2018 | Menefee Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Part of the Teratophoneini, a clade of tyrannosaurids exclusively known from southwestern North America [28] | |
| Dyoplosaurus | 1924 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | The holotype specimen preserves skin impressions [34] | |
| Dysganus | 1876 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Four species have been named, all from isolated teeth | |
| Dyslocosaurus | 1992 | Lance Formation?/Morrison Formation? (Late Jurassic, Kimmeridgian?/Late Cretaceous, Maastrichtian?) | United States ( Wyoming) | Has been suggested to have four claws on its hindlimbs | |
| Dystrophaeus | 1877 | Morrison Formation (Late Jurassic, Oxfordian) | United States ( Utah) | Inconsistent in phylogenetic placement, although undescribed remains could further clarify its relationships | |
| Edmontonia | 1928 | Dinosaur Park Formation, Horseshoe Canyon Formation, Judith River Formation? (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta)
United States ( Montana?) | Possessed forward-pointing, bifurcated spikes on its shoulders | |
| Edmontosaurus | 1917 | Frenchman Formation, Hell Creek Formation, Horseshoe Canyon Formation, Lance Formation, Prince Creek Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta
Saskatchewan)
United States ( Alaska
Colorado
Montana
North Dakota
South Dakota
Wyoming) | Known from multiple well-preserved specimens, including a few "mummies". Several were originally assigned to their own genera and/or species | |
| Einiosaurus | 1994 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Distinguished by its forward-curving nasal horn | |
| Enigmacursor | 2025 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado) | Known from a three-dimensionally preserved skeleton [35] | |
| Eolambia | 1998 | Cedar Mountain Formation (Late Cretaceous, Cenomanian) | United States ( Utah) | Remains of multiple individuals are known, making up much of the skeleton | |
| Eoneophron | 2024 | Hell Creek Formation (Late Cretaceous, Maastrichtian) | United States ( South Dakota) | Smaller than the contemporary Anzu | |
| Eotrachodon | 2016 | Mooreville Chalk (Late Cretaceous, Santonian) | United States ( Alabama) | Had a saurolophine-like skull despite its basal position [36] | |
| Eotriceratops | 2007 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | May have been the largest known ceratopsid | |
| Epichirostenotes | 2011 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | Its discovery allowed researchers to connect isolated caenagnathid body parts to each other | |
| Euoplocephalus | 1910 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Unusually, its palpebral bone was mobile, allowing it to be used as an eyelid [37] | |
| Falcarius | 2005 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | Transitional between generalized theropods and specialized therizinosaurs | |
| Ferrisaurus | 2019 | Tango Creek Formation (Late Cretaceous, Maastrichtian) | Canada ( British Columbia) | Its holotype was discovered close to a railway line [38] | |
| Fona | 2024 | Cedar Mountain Formation (Late Cretaceous, Cenomanian) | United States ( Utah) | Possibly a semi-fossorial animal based on the related Oryctodromeus [39] | |
| Foraminacephale | 2016 | Dinosaur Park Formation, Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Originally assigned to three different pachycephalosaurid genera | |
| Fosterovenator | 2014 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Wyoming) | Has been variously described as a ceratosaurid, a tetanuran or a close relative of Elaphrosaurus [40] | |
| Fruitadens | 2010 | Morrison Formation (Late Jurassic, Tithonian) | United States ( Colorado) | One of the smallest known ornithischians [41] | |
| Furcatoceratops | 2023 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Preserves most of the postcranial skeleton, a rarity for ceratopsids. Remains originally identified as Avaceratops | |
| Galeamopus | 2015 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Colorado
Wyoming) | One specimen is nearly complete, even preserving an associated skull | |
| Gargoyleosaurus | 1998 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Wyoming) | Combines features of both ankylosaurids and nodosaurids | |
| Gastonia | 1998 | Cedar Mountain Formation (Early Cretaceous, Valanginian to Barremian) | United States ( Utah) | Several concentrations of fossils may suggest this taxon lived in herds [42] | |
| Geminiraptor | 2010 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | The proportions of its maxilla are similar to those of Late Cretaceous troodontids | |
| Glishades | 2010 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Described as a basal hadrosauroid but may in fact be a juvenile saurolophine hadrosaurid [43] | |
| Glyptodontopelta | 2000 | Ojo Alamo Formation (Late Cretaceous, Maastrichtian) | United States ( New Mexico) | Originally interpreted as possessing a flat mosaic of osteoderms similar to the shields of glyptodonts | |
| Gojirasaurus | 1997 | Bull Canyon Formation (Late Triassic, Norian) | United States ( New Mexico) | May be a chimera consisting of undiagnostic theropod bones mixed with pseudosuchian vertebrae [44] | |
| Gorgosaurus | 1914 | Dinosaur Park Formation, Judith River Formation?, Two Medicine Formation? (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana?) | Dozens of specimens are known | |
| Gravitholus | 1979 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Potentially synonymous with Stegoceras [45] | |
| Gremlin | 2023 | Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Possessed a ridge running along the top of the skull | |
| Gryphoceratops | 2012 | Milk River Formation (Late Cretaceous, Santonian) | Canada ( Alberta) | Potentially the smallest adult ceratopsian known from North America | |
| Gryposaurus | 1914 | Bearpaw Formation?, Dinosaur Park Formation, Javelina Formation?, Kaiparowits Formation, Two Medicine Formation (Late Cretaceous, Santonian to Maastrichtian?) | Canada ( Alberta)
United States ( Montana
Texas?
Utah) | One specimen preserves impressions of a row of pyramidal scales running along its back [46] | |
| Hadrosaurus | 1858 | Woodbury Formation (Late Cretaceous, Campanian) | United States ( New Jersey) | Its holotype was the first dinosaur skeleton to be mounted | |
| Hagryphus | 2005 | Kaiparowits Formation (Late Cretaceous, Campanian) | United States ( Utah) | Large but only known from a single hand | |
| Hanssuesia | 2003 | Dinosaur Park Formation, Judith River Formation, Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | One dome preserves several lesions | |
| Haplocanthosaurus | 1903 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Colorado
Montana?
Wyoming) | One of the smallest sauropods of the Morrison Formation | |
| Hesperonychus | 2009 | Dinosaur Park Formation, Oldman Formation? (Late Cretaceous, Campanian) | Canada ( Alberta) | A common component of its habitat as indicated by the great number of its remains | |
| Hesperornithoides | 2019 | Morrison Formation (Late Jurassic, Oxfordian to Tithonian) | United States ( Wyoming) | Before its formal description, it had been nicknamed "Lori" | |
| Hesperosaurus | 2001 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Montana
Wyoming) | Two morphotypes of plates are known, which has been interpreted as an indication of sexual dimorphism [47] | |
| Hierosaurus | 1909 | Niobrara Formation (Late Cretaceous, Coniacian to Campanian) | United States ( Kansas) | Only known from a few bones, including osteoderms | |
| Hippodraco | 2010 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | Its tooth crowns were shaped like shields | |
| Hoplitosaurus | 1902 | Lakota Formation (Early Cretaceous, Barremian?) | United States ( South Dakota) | Known from some osteoderms, including spikes similar to those of Polacanthus | |
| Huehuecanauhtlus | 2012 | Unnamed formation (Late Cretaceous, Santonian) | Mexico ( Michoacán) | The southernmost non-hadrosaurid hadrosauroid known from North America [48] | |
| Hypacrosaurus | 1913 | Horseshoe Canyon Formation, Two Medicine Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta)
United States ( Montana) | Some juveniles of this genus were originally interpreted as dwarf lambeosaurines | |
| Hypsibema | 1869 | Marshalltown Formation?, Ripley Formation, Tar Heel/Coachman Formation (Late Cretaceous, Campanian) | United States ( Missouri
New Jersey?
North Carolina) | Potentially one of the largest non-hadrosaurid hadrosauroids | |
| Hypsirhophus | 1878 | Morrison Formation (Late Jurassic, Tithonian) | United States ( Colorado) | Usually seen as synonymous with Stegosaurus but may be a separate genus due to differences in its vertebrae [49] | |
| Iani | 2023 | Cedar Mountain Formation (Late Cretaceous, Cenomanian) | United States ( Utah) | Represents the family Tenontosauridae, a clade of North American rhabdodontomorphs [50] | |
| Iguanacolossus | 2010 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | Large and robustly built | |
| Invictarx | 2018 | Menefee Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Only known from a few bones but can be distinguished from other genera by characters of its osteoderms | |
| Issi | 2021 | Fleming Fjord Formation (Late Triassic, Norian) | Greenland (Sermersooq) | Originally described as an exemplar of Plateosaurus | |
| Jeyawati | 2010 | Moreno Hill Formation (Late Cretaceous, Turonian to Coniacian) | United States ( New Mexico) | Its postorbital bone had a rugose texture | |
| Judiceratops | 2013 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Unusually, its brow horns were teardrop-shaped in cross-section | |
| Kaatedocus | 2012 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Wyoming) | Originally interpreted as a diplodocid although one study finds it to be more likely a basal dicraeosaurid [51] | |
| Kayentavenator | 2010 | Kayenta Formation (Early Jurassic, Sinemurian to Pliensbachian) | United States ( Arizona) | Described in a book published through an online print-on-demand service | |
| Koparion | 1994 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Utah) | Known from a single tooth which may have come from a troodontid | |
| Kosmoceratops | 2010 | Kaiparowits Formation (Late Cretaceous, Campanian) | United States ( Utah) | Possessed fifteen horns and horn-like structures, including eight hornlets folding down from the top of the frill | |
| Kritosaurus | 1910 | El Picacho Formation?, Javelina Formation?, Kirtland Formation, Ojo Alamo Formation? (Late Cretaceous, Campanian to Maastrichtian?) | United States ( New Mexico
Texas?) | Had an elevated nasal bone with an enlarged nasal cavity to match | |
| Labocania | 1974 | Cerro del Pueblo Formation, La Bocana Roja Formation (Late Cretaceous, Cenomanian? to Campanian) | Mexico ( Baja California
Coahuila) | The description of the second species, L. aguillonae, suggests a position within the tyrannosaurid clade Teratophoneini [52] | |
| Lambeosaurus | 1923 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Possessed a hollow head crest that varied in shape between species, sexes and ages. Most familiarly, it was hatchet-shaped in adult male L. lambei | |
| Laosaurus | 1878 | Morrison Formation (Late Jurassic, Oxfordian to Tithonian) | United States ( Wyoming) | Several referred specimens have been reassigned to other taxa | |
| Latirhinus | 2012 | Cerro del Pueblo Formation (Late Cretaceous, Campanian) | Mexico ( Coahuila) | As described, it represented a chimera composed of lambeosaurine and saurolophine remains. [53] The exact holotypic bones belonged to a lambeosaurine [54] | |
| Lepidus | 2015 | Colorado City Formation (Late Triassic, Norian) | United States ( Texas) | Muscle scars are preserved on the holotype bones | |
| Leptoceratops | 1914 | Hell Creek Formation, Lance Formation, Scollard Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta)
United States ( Montana
Wyoming) | Analysis of its teeth shows it could chew like a mammal, an adaptation to eating tough, fibrous plants [55] | |
| Leptorhynchos | 2013 | Aguja Formation (Late Cretaceous, Campanian) | United States ( Texas) | Had a slightly upturned mandible similar to those of oviraptorids | |
| Lokiceratops | 2024 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Unusually for a ceratopsid, its frill ornamentations were bilaterally asymmetrical. Closely related to Albertaceratops and Medusaceratops [56] | |
| Lophorhothon | 1960 | Mooreville Chalk, Tar Heel/Coachman Formation? (Late Cretaceous, Campanian) | United States ( Alabama
North Carolina?) | Although incomplete, the holotype skull preserves evidence of a crest | |
| Lythronax | 2013 | Wahweap Formation (Late Cretaceous, Campanian) | United States ( Utah) | Already had the forward-directed orbits of derived tyrannosaurids despite its early age | |
| Machairoceratops | 2016 | Wahweap Formation (Late Cretaceous, Campanian) | United States ( Utah) | Possessed two long, forward-pointing horns on the top of its frill | |
| Magnapaulia | 2012 | El Gallo Formation (Late Cretaceous, Campanian) | Mexico ( Baja California) | Has been suggested to be semi-aquatic due to its tall, narrow tail [57] | |
| Maiasaura | 1979 | Oldman Formation, Two Medicine Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | Remains of hundreds of individuals, including juveniles, eggs and nests, have been found at a single site [58] | |
| Malefica | 2022 | Aguja Formation (Late Cretaceous, Campanian) | United States ( Texas) | Its discovery suggests a greater diversity of basal hadrosaurids than previously thought | |
| Maraapunisaurus | 2018 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Colorado) | Named from a single, lost vertebra of immense size | |
| Marshosaurus | 1976 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Colorado?
Utah) | Potentially a close relative of Piatnitzkysaurus and Condorraptor [59] | |
| Martharaptor | 2012 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | Had not yet acquired the robust feet of derived therizinosaurs | |
| Medusaceratops | 2010 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Possessed elongated spikes curving away from the sides of its frill | |
| Menefeeceratops | 2021 | Menefee Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | One of the oldest centrosaurines | |
| Mercuriceratops | 2014 | Dinosaur Park Formation, Judith River Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | Had "wing"-like projections on its squamosal bones | |
| Mexidracon | 2025 | Cerro del Pueblo Formation (Late Cretaceous, Campanian) | Mexico ( Coahuila) | Had unusually long hands for an ornithomimosaur | |
| Microvenator | 1970 | Cloverly Formation (Early Cretaceous, Albian) | United States ( Montana) | Teeth from Deinonychus have been mistakenly attributed to this genus | |
| Mierasaurus | 2017 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | One of the latest-surviving turiasaurs [60] | |
| Moabosaurus | 2017 | Cedar Mountain Formation (Early Cretaceous, Aptian) | United States ( Utah) | Described as a macronarian [61] but has since been reinterpreted as a turiasaur closely related to Mierasaurus [60] | |
| Monoclonius | 1876 | Dinosaur Park Formation, Judith River Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | Only known from indistinct remains of juveniles and subadults | |
| Montanoceratops | 1951 | Horseshoe Canyon Formation?, St. Mary River Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta)
United States ( Montana) | Often restored with a short nasal horn although this may be a misplaced cheek horn [62] | |
| Moros | 2019 | Cedar Mountain Formation (Late Cretaceous, Cenomanian) | United States ( Utah) | The proportions of its metatarsals are similar to those of ornithomimids | |
| Mymoorapelta | 1994 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Utah) | The first ankylosaur described from the Morrison Formation | |
| Naashoibitosaurus | 1993 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Like other kritosaurins, it possessed a nasal arch, but it was not as tall as that of Gryposaurus | |
| Nanosaurus | 1877 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Wyoming) | Several referred specimens were originally assigned to other genera | |
| Nanotyrannus | 1988 | Hell Creek Formation (Late Cretaceous, Maastrichtian) | United States ( Montana) | Remains referred to this genus have been historically believed to be juvenile Tyrannosaurus specimens, but its validity was later affirmed in 2025 | |
| Nanuqsaurus | 2014 | Prince Creek Formation (Late Cretaceous, Maastrichtian) | United States ( Alaska) | Described as a dwarf tyrannosaurid although undescribed remains suggest a size comparable to Albertosaurus [63] | |
| Nasutoceratops | 2013 | Kaiparowits Formation (Late Cretaceous, Campanian) | United States ( Utah) | Possessed an enlarged nasal cavity and two long, curving horns similar to those of modern cattle | |
| Navajoceratops | 2020 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Had a distinctive notch at the very top of its frill, similar to its potential ancestor Pentaceratops [64] | |
| Nedcolbertia | 1998 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | Known from three partial skeletons. The specific name, justinhofmanni, honors a six-year-old schoolboy who won a contest to have a dinosaur named after him | |
| Nevadadromeus | 2022 | Willow Tank Formation (Late Cretaceous, Cenomanian) | United States ( Nevada) | The first non-avian dinosaur described from Nevada | |
| Niobrarasaurus | 1995 | Niobrara Formation (Late Cretaceous, Coniacian to Campanian) | United States ( Kansas) | Originally mistakenly believed to have been aquatic [65] | |
| Nodocephalosaurus | 1999 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Closely related to Asian ankylosaurids [66] | |
| Nodosaurus | 1889 | Frontier Formation (Late Cretaceous, Cenomanian to Coniacian) | United States ( Wyoming) | Its armor included banded dermal plates interspersed by bony nodules | |
| Nothronychus | 2001 | Moreno Hill Formation, Tropic Shale (Late Cretaceous, Turonian) | United States ( New Mexico
Utah) | Would have lived in the marshes and swamps [67] along the Turonian shoreline [68] | |
| Ojoraptorsaurus | 2011 | Ojo Alamo Formation (Late Cretaceous, Maastrichtian) | United States ( New Mexico) | Only known from an incomplete pair of pubes | |
| Oohkotokia | 2013 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Potentially a synonym of Scolosaurus [69] | |
| Ornatops | 2021 | Menefee Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Preserves a pair of bumps on its skull which may have anchored a crest | |
| Ornitholestes | 1903 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Wyoming) | May have possessed a sickle claw similar to those of dromaeosaurids [70] | |
| Ornithomimus | 1890 | Denver Formation, Dinosaur Park Formation, Ferris Formation?, Horseshoe Canyon Formation, Kaiparowits Formation? (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta)
United States ( Colorado
Utah?
Wyoming) | One referred specimen preserves impressions of ostrich-like feathers covering most of its body [71] | |
| Orodromeus | 1988 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Eggs considered to belong to this taxon may have actually come from a troodontid [72] | |
| Oryctodromeus | 2007 | Blackleaf Formation, Wayan Formation (Late Cretaceous, Cenomanian) | United States ( Idaho
Montana) | Several specimens have been preserved in burrows | |
| Osmakasaurus | 2011 | Lakota Formation (Early Cretaceous, Valanginian) | United States ( South Dakota) | Originally named as a species of Camptosaurus | |
| Pachycephalosaurus | 1943 | Hell Creek Formation, Lance Formation, Scollard Formation? (Late Cretaceous, Maastrichtian) | Canada ( Alberta?)
United States ( Montana
South Dakota
Wyoming) | Possessed a tall, rounded head dome surrounded by bony knobs | |
| Pachyrhinosaurus | 1950 | Horseshoe Canyon Formation, Prince Creek Formation, St. Mary River Formation, Wapiti Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta)
United States ( Alaska) | Three species have been named, each with a unique pattern of cranial ornamentation | |
| Palaeoscincus | 1856 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Although many restorations depict it with the spikes of Edmontonia and the tail club of Ankylosaurus , this is most likely incorrect | |
| Panoplosaurus | 1919 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Unlike other nodosaurids, it lacked enlarged spikes | |
| Parasaurolophus | 1922 | Dinosaur Park Formation, Fruitland Formation, Kaiparowits Formation, Kirtland Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( New Mexico
Utah) | Possessed a curved, hollow crest that varied in size between species | |
| Paraxenisaurus | 2020 | Cerro del Pueblo Formation (Late Cretaceous, Campanian) | Mexico ( Coahuila) | Described as the first deinocheirid from North America | |
| Parksosaurus | 1937 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | Had long toes which may be an adaptation to walking on soft soils in watercourses and marshlands [67] | |
| Paronychodon | 1876 | Hell Creek Formation, Judith River Formation, Lance Formation (Late Cretaceous, Campanian to Maastrichtian) | United States ( Montana
North Dakota
South Dakota
Wyoming) | Only known from highly distinctive teeth | |
| Pawpawsaurus | 1996 | Paw Paw Formation (Early Cretaceous, Albian) | United States ( Texas) | Had enlarged nasal cavities that gave it an acute sense of smell, even more powerful than that of contemporary theropods [73] | |
| Pectinodon | 1982 | Hell Creek Formation, Lance Formation (Late Cretaceous, Maastrichtian) | United States ( Wyoming) | Had comb-like serrations on its teeth | |
| Peloroplites | 2008 | Cedar Mountain Formation (Late Cretaceous, Cenomanian to Turonian) | United States ( Utah) | One of the largest known nodosaurids | |
| Pentaceratops | 1923 | Fruitland Formation, Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Its epijugal bones, the hornlets under its eyes, were relatively large | |
| Planicoxa | 2001 | Cedar Mountain Formation (Early Cretaceous, Barremian to Albian) | United States ( Utah) | The rear of its ilium was characteristically flat | |
| Platypelta | 2018 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Originally assigned to Euoplocephalus but was given its own genus because of several morphological differences | |
| Platytholus | 2023 | Hell Creek Formation (Late Cretaceous, Maastrichtian) | United States ( Montana) | Differs from juveniles of the contemporary Pachycephalosaurus and Sphaerotholus , hence its classification as a new genus | |
| Podokesaurus | 1911 | Portland Formation (Early Jurassic, Hettangian to Sinemurian) | United States ( Massachusetts) | May have had a tail one and a half times longer than the rest of its skeleton [74] | |
| Polyodontosaurus | 1932 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | May be identical to Latenivenatrix [75] | |
| Polyonax | 1874 | Denver Formation (Late Cretaceous, Maastrichtian) | United States ( Colorado) | Poorly known | |
| Prenoceratops | 2004 | Oldman Formation, Two Medicine Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | The only basal neoceratopsian known from a bonebed | |
| Priconodon | 1888 | Arundel Formation (Early Cretaceous, Aptian to Albian) | United States ( Maryland) | Large but only known from teeth | |
| Probrachylophosaurus | 2015 | Foremost Formation, Judith River Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | Shows a skull morphology transitional between crestless and crested brachylophosaurins | |
| Propanoplosaurus | 2011 | Patuxent Formation (Early Cretaceous, Aptian) | United States ( Maryland) | Only known from the imprints of a neonate skeleton | |
| Prosaurolophus | 1916 | Dinosaur Park Formation, Two Medicine Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana) | Had a relatively large head for a hadrosaur | |
| Protohadros | 1998 | Woodbine Formation (Late Cretaceous, Cenomanian) | United States ( Texas) | Possessed a downturned jaw which may be an adaptation to grazing on low-growing plants | |
| Pteropelyx | 1889 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Potentially synonymous with Corythosaurus , although this cannot be confirmed due to the lack of cranial remains [76] | |
| Rativates | 2016 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Originally described as a specimen of Struthiomimus | |
| Regaliceratops | 2015 | St. Mary River Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | Possessed a series of large, pentagonal plates lining its frill | |
| Richardoestesia | 1990 | Aguja Formation, Dinosaur Park Formation, Ferris Formation?, Hell Creek Formation?, Horseshoe Canyon Formation?, Lance Formation?, Scollard Formation? (Late Cretaceous, Campanian to Maastrichtian?) | Canada ( Alberta)
United States ( Montana?
Texas
Wyoming?) | Teeth assigned to this genus have been recovered all around the world, in deposits spanning from the Jurassic to the Cretaceous, although they may not represent a single taxon | |
| Rugocaudia | 2012 | Cloverly Formation (Early Cretaceous, Aptian to Albian) | United States ( Montana) | Some of this genus' remains include several caudal vertebrae | |
| Sarahsaurus | 2011 | Kayenta Formation (Early Jurassic, Sinemurian to Pliensbachian) | United States ( Arizona) | Possessed strong hands which may indicate a feeding specialization | |
| Saurolophus | 1912 | Horseshoe Canyon Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta) | Had a short, solid crest that pointed directly upwards. A larger, more well-known species has been found in Mongolia | |
| Sauropelta | 1970 | Cedar Mountain Formation?, Cloverly Formation (Early Cretaceous, Albian) | United States ( Montana
Utah?
Wyoming) | Its tail had at least forty vertebrae, making up half of its total body length | |
| Saurophaganax | 1995 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( New Mexico?
Oklahoma) | Originally described as a large theropod, but was later suggested to be a chimera of sauropod and theropod bones. The holotype bone may have belonged to a sauropod [77] | |
| Sauroposeidon | 2000 | Antlers Formation, Cloverly Formation, Glen Rose Formation, Twin Mountains Formation (Early Cretaceous, Aptian to Albian) | United States ( Oklahoma
Texas
Wyoming) | Could raise its head up to 18 metres (59 ft) in the air, the height of a six-story building [78] | |
| Saurornitholestes | 1978 | Dinosaur Park Formation, Donoho Creek Formation, Kirtland Formation, Mooreville Chalk, Oldman Formation, Tar Heel/Coachman Formation, Two Medicine Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta)
United States ( Alabama
Montana
New Mexico
South Carolina) | Its second premaxillary teeth could be adapted to preening feathers [79] | |
| Scolosaurus | 1928 | Dinosaur Park Formation, Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Once widely believed to be synonymous with other Campanian ankylosaurids | |
| Scutellosaurus | 1981 | Kayenta Formation (Early Jurassic, Sinemurian) | United States ( Arizona) | Had hundreds of osteoderms arranged in rows along its back and tail | |
| Segisaurus | 1936 | Navajo Sandstone (Early Jurassic, Pliensbachian to Toarcian) | United States ( Arizona) | Preserves evidence of a wishbone similar to that of modern birds | |
| Seitaad | 2010 | Navajo Sandstone (Early Jurassic, Pliensbachian) | United States ( Utah) | The holotype may have died when a sand dune collapsed on it [80] | |
| Siats | 2013 | Cedar Mountain Formation (Late Cretaceous, Cenomanian) | United States ( Utah) | Large but inconsistent in phylogenetic placement | |
| Sierraceratops | 2022 | Hall Lake Formation (Late Cretaceous, Campanian to Maastrichtian) | United States ( New Mexico) | May be part of a unique clade of chasmosaurine ceratopsids only known from southern Laramidia [81] | |
| Silvisaurus | 1960 | Dakota Formation (Early Cretaceous to Late Cretaceous, Albian to Cenomanian) | United States ( Kansas) | Hypothesized to live in a forested habitat | |
| Smitanosaurus | 2020 | Morrison Formation (Late Jurassic, Oxfordian to Tithonian) | United States ( Colorado) | Only known from a partial skull and some vertebrae | |
| Sonorasaurus | 1998 | Turney Ranch Formation (Early Cretaceous to Late Cretaceous, Albian to Cenomanian) | United States ( Arizona) | State dinosaur of Arizona | |
| Sphaerotholus | 2002 | Dinosaur Park Formation, Frenchman Formation, Hell Creek Formation, Horseshoe Canyon Formation, Kirtland Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta
Saskatchewan)
United States ( Montana
New Mexico) | Five species have been named, all known from skull elements. Lived in a broad range | |
| Spiclypeus | 2016 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Has been described as "boldly audacious" [82] | |
| Spinops | 2011 | Dinosaur Park Formation?/Oldman Formation? (Late Cretaceous, Campanian) | Canada ( Alberta) | Described almost a century after its remains were collected | |
| Stegoceras | 1902 | Dinosaur Park Formation, Fruitland Formation?, Kirtland Formation?, Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( New Mexico?) | May have been an indiscriminate bulk-feeder due to the shape of its snout [83] | |
| Stegopelta | 1905 | Frontier Formation (Early Cretaceous to Late Cretaceous, Albian to Cenomanian) | United States ( Wyoming) | May have possessed a sacral shield similar to other nodosaurids | |
| Stegosaurus | 1877 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Wyoming) | Had a single alternating row of large, kite-shaped plates | |
| Stellasaurus | 2020 | Two Medicine Formation (Late Cretaceous, Campanian) | United States ( Montana) | Possessed an enlarged, thickened nasal horn | |
| Stenonychosaurus | 1932 | Dinosaur Park Formation, Two Medicine Formation? (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana?) | Its brain-to-body mass ratio is one of the highest of any non-avian dinosaur. Possibly synonymous with Troodon [84] | |
| Stephanosaurus | 1914 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Poorly known | |
| Stokesosaurus | 1974 | Morrison Formation (Late Jurassic, Kimmeridgian? to Tithonian) | United States ( South Dakota?
Utah) | Only known from a few remains but they are enough to tell that it was a tyrannosauroid | |
| Struthiomimus | 1917 | Horseshoe Canyon Formation?, Lance Formation?, Oldman Formation (Late Cretaceous, Campanian to Maastrichtian?) | Canada ( Alberta)
United States ( Wyoming?) | Known from many specimens, indicating it was a common animal | |
| Styracosaurus | 1913 | Dinosaur Park Formation, Two Medicine Formation? (Late Cretaceous, Campanian) | Canada ( Alberta)
United States ( Montana?) | Possessed several long horns jutting out from the top of its frill, the patterns of which could have varied between individuals [85] | |
| Supersaurus | 1985 | Morrison Formation (Late Jurassic, Tithonian) | United States ( Colorado
Wyoming) | Several remains were originally believed to represent their own genera | |
| Suskityrannus | 2019 | Moreno Hill Formation (Late Cretaceous, Turonian) | United States ( New Mexico) | Small yet already possessed several features of larger, more derived tyrannosaurids, including an arctometatarsus | |
| Suuwassea | 2004 | Morrison Formation (Late Jurassic, Oxfordian to Tithonian) | United States ( Montana) | Shares features with both diplodocids and dicraeosaurids, but is most likely a member of the latter group [15] [51] | |
| Talos | 2011 | Kaiparowits Formation (Late Cretaceous, Campanian) | United States ( Utah) | The holotype specimen preserves a pathology on its sickle claw [86] | |
| Tanycolagreus | 2005 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Utah
Wyoming) | Had a long, blunt snout | |
| Tatankacephalus | 2009 | Cloverly Formation (Early Cretaceous, Aptian to Albian) | United States ( Montana) | Retained premaxillary teeth in its upper jaws, a basal trait | |
| Tawa | 2009 | Chinle Formation (Late Triassic, Norian) | United States ( New Mexico) | Well-preserved but inconsistent in phylogenetic placement | |
| Tenontosaurus | 1970 | Antlers Formation, Arundel Formation, Cedar Mountain Formation, Cloverly Formation, Paluxy Formation, Twin Mountains Formation, Wayan Formation (Early Cretaceous, Aptian to Albian) | United States ( Idaho
Maryland
Montana
Oklahoma
Texas
Utah) | Remains of this genus are often found associated with skeletons of Deinonychus [87] | |
| Teratophoneus | 2011 | Kaiparowits Formation (Late Cretaceous, Campanian) | United States ( Utah) | Its snout was shorter and deeper than those of other tyrannosaurids | |
| Terminocavus | 2020 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Had a teardrop-shaped hole on the top of its frill which was almost closed off by a pair of epoccipitals | |
| Texacephale | 2010 | Aguja Formation (Late Cretaceous, Campanian) | United States ( Texas) | Might represent a specimen of Stegoceras [88] | |
| Texasetes | 1995 | Paw Paw Formation (Early Cretaceous, Albian) | United States ( Texas) | Potentially synonymous with Pawpawsaurus | |
| Thanatotheristes | 2020 | Foremost Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | A close relative of Daspletosaurus [89] | |
| Theiophytalia | 2006 | Purgatoire Formation (Early Cretaceous, Aptian to Albian) | United States ( Colorado) | Only known from a skull originally referred to Camptosaurus | |
| Thescelosaurus | 1913 | Frenchman Formation, Hell Creek Formation, Lance Formation, Laramie Formation, Scollard Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta
Saskatchewan)
United States ( Colorado
Montana
North Dakota
South Dakota
Wyoming) | One specimen was originally considered to have preserved its heart, although this was later found to be a mineral concretion [90] | |
| Thespesius | 1856 | Lance Formation (Late Cretaceous, Maastrichtian) | United States ( South Dakota) | Once suggested to be a possible Miocene mammal | |
| Tichosteus | 1877 | Morrison Formation (Late Jurassic, Kimmeridgian) | United States ( Colorado) | Two species have been named, both from isolated vertebrae | |
| Titanoceratops | 2011 | Fruitland Formation?/Kirtland Formation? (Late Cretaceous, Campanian) | United States ( New Mexico) | Potentially a large, old specimen of Pentaceratops [64] | |
| Tlatolophus | 2021 | Cerro del Pueblo Formation (Late Cretaceous, Campanian) | Mexico ( Coahuila) | Possessed a short, broad crest resembling an inverted comma | |
| Torosaurus | 1891 | Frenchman Formation, Hell Creek Formation, Lance Formation, North Horn Formation?, Scollard Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta
Saskatchewan)
United States ( Colorado?
Montana?
New Mexico?
North Dakota?
South Dakota
Texas?
Utah?
Wyoming) | Once believed to be potentially synonymous with Triceratops | |
| Torvosaurus | 1979 | Morrison Formation (Late Jurassic, Kimmeridgian to Tithonian) | United States ( Colorado
Wyoming) | Had short but powerfully built arms. Several species, many of them unnamed, have been found in Europe, South America and possibly Africa | |
| Tototlmimus | 2016 | Packard Formation (Late Cretaceous, Campanian) | Mexico ( Sonora) | The southernmost ornithomimid known from North America | |
| Trachodon | 1856 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Several remains assigned to this genus actually belong to other taxa, most notably Edmontosaurus | |
| Triceratops | 1889 | Denver Formation, Evanston Formation, Hell Creek Formation, Lance Formation, Laramie Formation, Scollard Formation (Late Cretaceous, Maastrichtian) | Canada ( Alberta
Saskatchewan?)
United States ( Colorado
Montana
South Dakota
Wyoming) | A common ceratopsid with long brow horns and a short nasal horn | |
| Trierarchuncus | 2020 | Hell Creek Formation (Late Cretaceous, Maastrichtian) | United States ( Montana) | Known from remains of different sizes which depict how the claws of alvarezsaurids grew more hooked as they aged | |
| Troodon | 1856 | Judith River Formation, Two Medicine Formation? (Late Cretaceous, Campanian) | United States ( Montana) | Usually seen as a dubious, undiagnostic genus, but a later study recommends the formal designation of a neotype to preserve its validity based on new troodontid fossil material discovered in the Two Medicine Formation [84] | |
| Tyrannosaurus | 1905 | Frenchman Formation, Hall Lake Formation, Hell Creek Formation, Lance Formation, North Horn Formation, Scollard Formation, Willow Creek Formation (Late Cretaceous, Campanian to Maastrichtian) | Canada ( Alberta
Saskatchewan)
United States ( Colorado
Montana
New Mexico
South Dakota
Utah
Wyoming) | The last, largest and most well-known tyrannosaurid | |
| Unescoceratops | 2012 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Had the roundest teeth of any known leptoceratopsid | |
| Utahceratops | 2010 | Kaiparowits Formation (Late Cretaceous, Campanian) | United States ( Utah) | Almost the entire skeleton is known, including the skull | |
| Utahraptor | 1993 | Cedar Mountain Formation (Early Cretaceous, Berriasian to Valanginian) | United States ( Utah) | Very large and powerfully built | |
| Uteodon | 2011 | Morrison Formation (Late Jurassic, Tithonian) | United States ( Utah) | May be a species of Camptosaurus , with a referred braincase being from Dryosaurus [91] | |
| Utetitan | 2025 | Black Peaks Formation?, Javelina Formation?, North Horn Formation (Late Cretaceous, Maastrichtian) | United States ( Texas?
Utah) | Known from partial skeletons originally identified as possible northern specimens of Alamosaurus | |
| Vagaceratops | 2010 | Dinosaur Park Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Possessed a row of fused epoccipitals folding over the top of the frill | |
| Velafrons | 2007 | Cerro del Pueblo Formation (Late Cretaceous, Campanian) | Mexico ( Coahuila) | May have had elongated neural spines similar to those of Hypacrosaurus altispinus | |
| Venenosaurus | 2001 | Cedar Mountain Formation (Early Cretaceous, Aptian to Albian) | United States ( Utah) | Its skeleton has traits of both titanosaurs and more basal macronarians | |
| Wendiceratops | 2015 | Oldman Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Had three pairs of enlarged, curved epiparietals at the very top of its frill | |
| Xenoceratops | 2012 | Foremost Formation (Late Cretaceous, Campanian) | Canada ( Alberta) | Possessed two long spikes at the top of its frill with smaller knobs at their bases | |
| Yehuecauhceratops | 2017 | Aguja Formation (Late Cretaceous, Campanian) | Mexico ( Coahuila) | One of the smallest known ceratopsids | |
| Yurgovuchia | 2012 | Cedar Mountain Formation (Early Cretaceous, Valanginian) | United States ( Utah) | May have had a flexible tail due to the structure of its caudal vertebrae | |
| Zapsalis | 1876 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Some teeth referred to this genus actually belong to Saurornitholestes [79] | |
| Zephyrosaurus | 1980 | Cloverly Formation (Early Cretaceous, Aptian to Albian) | United States ( Montana) | Currently only known from fragmentary remains but several undescribed specimens exist [92] | |
| Ziapelta | 2014 | Kirtland Formation (Late Cretaceous, Campanian) | United States ( New Mexico) | Many specimens are known, most from the front part of the animal | |
| Zuniceratops | 1998 | Moreno Hill Formation (Late Cretaceous, Turonian to Coniacian) | United States ( New Mexico) | Carried a pair of brow horns despite not being a member of the Ceratopsidae | |
| Zuul | 2017 | Judith River Formation (Late Cretaceous, Campanian) | United States ( Montana) | Preserves several osteoderms, keratin and skin remains | |