Vertebrate fauna of the Maastrichtian stage

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This is an incomplete list that briefly describes vertebrates that were extant during the Maastrichtian, a stage of the Late Cretaceous Period which extended from 72.1 to 66 million years before present. This was the last time period in which non-avian dinosaurs, pterosaurs, plesiosaurs, and mosasaurs existed.

Amphibians[edit]

Amphibians of the Maastrichtian
Taxa Presence Location Description Images
  • Albanerpeton galaktion
  • Albanerpeton gracilis
  • Albanerpeton nexuosus
105.3-66.043 MA, Albian to Maastrichtian Canada, USA A salamander-like albanerpetontid that thrived in both North America and Europe from the Early Cretaceous to the late Pliocene. Members of the genus had a robust head and neck which likely allowed them to actively burrow, and they lived in a wide range of environments.
  • Beelzebufo ampinga
70 Ma Maevarano Formation, Mahajanga Province, Madagascar A southern frog that was the largest frog to ever live. It is known to, with its expansive mouth, eat relatively large prey, perhaps even juvenile dinosaurs.
  • Habrosaurus dilatus
Maastrichtian to Danian Lance Formation, Wyoming, USA

Hell Creek Formation, Montana, USA

A large sirenid, about the size of a hellbender. The palate is specialized for crushing, with a series of blunt teeth arranged in rows, suggesting that it may have fed on hard-bodied prey such as crayfish or snails.
  • Scotiophryne pustulosa
125-60.5 Ma, Aptian to Danian Hell Creek Formation, Montana, USA

Ornithischians[edit]

Ankylosaurs[edit]

Ankylosaurs of the Maastrichtian
Taxa Presence Location Description Images
  • Ankylosaurus magniventris
66.5-66 Ma Hell Creek Formation, Montana, USA

Scollard Formation, Alberta, Canada

The largest ankylosaur.
  • Anodontosaurus lambei
72.8-67 Ma, Campanian to Maastrichtian Horseshoe Canyon Formation, Alberta, Canada
  • Brachypodosaurus gravis
66 Ma Lameta Formation, India An unspecified ankylosaur, originally described as a stegosaur.
  • Edmontonia longiceps
  • Edmontonia schlessmani
76.5-66 Ma, Campanian to Maastrichtian Horseshoe Canyon Formation, Alberta, Canada

Lance Formation, Wyoming, USA

A bulky nodosaurid at roughly 6.6 m (22 ft) long and 2 m (6 ft) high. It had small, ridged bony plates on its back and head and many sharp spikes along its back and tail. The four largest spikes jutted out from the shoulders on each side, two of which were split into subspines in some specimens. Its skull had a pear-like shape when viewed from above.
  • Glyptodontopelta mimus
69-66 Ma Ojo Alamo Formation, New Mexico, USA
  • Struthiosaurus austriacus
  • Struthiosaurus languedocensis
  • Struthiosaurus transylvanicus
85-66 Ma, Santonian to Maastrichtian Sanpetru Formation, Hunedoara County, Romania
  • Tarchia kailanae
84.9-70.6 Ma, Santonian to Maastrichtian Barun Goyot Formation, Mongolia Currently the geologically youngest known of all Asian ankylosaurs.

Ceratopsians[edit]

Taxa Presence Location Description Images
  1. Agathaumas sylvestris
66 Ma Lance Formation, Wyoming, USA
  1. Anchiceratops ornatus
72-71 Ma St. Mary River Formation, Alberta, Canada
  1. Arrhinoceratops brachyops
70.6-70 Ma Horseshoe Canyon Formation, Alberta, Canada
  1. Bravoceratops polyphemus
70 Ma Javelina Formation, Texas, USA
  1. Coahuilaceratops magnacuerna
72.5-71.4 Ma, Campanian to Maastrichtian Cerro del Pueblo Formation, Coahuila, Mexico A chasmosaurine thought to possess among the largest horns of any dinosaur currently known, rivaling in absolute size those of larger chasmosaurines like Triceratops and Torosaurus. The horns themselves are estimated to have been up to 4 feet (1.2 m) long.
  1. Eotriceratops xerinsularis
68-67.6 Ma Horseshoe Canyon Formation, Alberta, Canada A chasmosaurine differing from other chasmosaurines in unique features of the skull bones, such as an unusually pronounced jugal horn and extremely elongated, flattened and spindly epoccipitals, similar to Torosaurus utahensis.
  1. Leptoceratops gracilis
66.8-66 Ma Hell Creek Formation, Montana, USA

Lance Formation, Alberta, Canada

  • Scollard Formation, Alberta, Canada
  1. Micropachycephalosaurus hongtuyanensis
70.6-69.5 Ma Wangshi Group, Shandong, China A basal-looking ceratopsian and among the smallest of non-avian dinosaurs. It was originally thought to be a pachycephalosaur.
  1. Montanoceratops cerorhynchos
70 Ma St. Mary River Formation, Montana, USA A leptoceratopsid distinguished by the presence of claws, rather than hooves, and by having teeth in its upper jaw, rather than a toothless beak. It was once thought to have a horn on its nose but that was a misplaced cheek horn. Another unusual feature was the presence of tall spines on the bones of the tail. Although these would not have been visible during life, they would have made the tail unusually deep in cross-section and highly flexible (possibly used in intra-species signaling).
  1. Nedoceratops hatcheri
67-66 Ma Lance Formation, Wyoming, USA A ceratopsid that was probably an ontogenetic stage of Triceratops. However, on closer examination, it differs: there is just a rounded stump where the nasal horn should be and the brow horns stand almost vertically. Compared to Triceratops skulls, it is slightly larger than average, but its face is rather short. There also are large holes in the frill, unlike other Triceratops skulls known. Some of these may be pathological, others seem to be genetic.
  1. Ojoceratops fowleri
68 Ma Ojo Alamo Formation, New Mexico, USA A ceratopsid, possibly synonymous with Triceratops or Eotriceratops, or probably ancestral to Triceratops. It is very similar to Triceratops, though it is from an earlier time of the Maastrichtian and has a more squared-off frill.
  1. Pachyrhinosaurus canadensis
  2. Pachyrhinosaurus lakustai
  3. Pachyrhinosaurus perotorum
73.5-69 Ma, Campanian to Maastrichtian
  1. Polyonax mortuarinus
66.5 Ma Denver Formation, Colorado, USA
  1. Protoceratops andrewsi
  2. Protoceratops hellenikorhinus
75-71 Ma, Campanian to Maastrichtian Djadochta Formation, Mongolia

Bayan Mandahu Formation, Inner Mongolia, China

  1. Sinoceratops zhuchengensis
72-66 Ma Xingezhuang Formation, Shandong, China The first discovered ceratopsid discovered in China. It is one of the largest known centrosaurines.
  1. Tatankaceratops sacrisonorum
66 Ma Hell Creek Formation, South Dakota, USA A chasmosaurine, probably a juvenile specimen of Triceratops.
  1. Torosaurus latus
  2. Torosaurus utahensis
68-66 Ma Lance Formation, Wyoming, USA

Hell Creek Formation, Montana, USA

  1. Triceratops horridus
  2. Triceratops prorsus
68-66 Ma Hell Creek Formation, Montana, USA

Lance Formation, Wyoming, USA

  1. Zhuchengceratops inexpectus
70 Ma Wangshi Group, Shandong, China A leptoceratopsid with a particularly massive and deep 50 cm-long mandible that is also thin transversely. This and a number of other autapomorphies unique to the genus lend it significance for increasing the morphological disparity and the taxonomic diversity of leptoceratopsidae.

Ornithopoda[edit]

Ornithopods of the Maastrichtian
Taxa Presence Location Description Images
  1. Amurosaurus riabinini
66 Ma Udurchukan Formation, Amur Oblast, Russia
  1. Arenysaurus ardevoli
66 Ma Spain
  1. Bactrosaurus johnsoni
70 Ma Iren Dabasu Formation, Inner Mongolia, China
  1. Barsboldia sicinskii
70 Ma Nemegt Formation, Mongolia
  1. Blasisaurus canudoi
66 Ma Spain
  1. Canardia garonnensis
67.5-66 Ma Marnes d'Auzas Formation, France
  1. Charonosaurus jiayinensis
66 Ma Yuliangze Formation, Heilongjiang, China Appearing similar in skull shape to Parasaurolophus
  1. Edmontosaurus regalis
  2. Edmontosaurus annectens
73-66 Ma, Campanian to Maastrichtian USA, Canada E. annectens was previously called Anatotitan. E. regalis is now known to have bore a comb-like crest of skin and scales, similar to a galliform.
  1. Gilmoreosaurus mongoliensis
70 Ma Iren Dabasu Formation, Inner Mongolia, China
  1. Hypacrosaurus altispinus
75-67 Ma, Campanian to Maastrichtian Horseshoe Canyon Formation, Alberta, Canada A lambeosaurine that has a tall, hollow rounded crest similar to Corythosaurus, although not as large and straight.
  1. Kerberosaurus manakini
66 Ma Tsagayan Formation, Russia
  1. Koutalisaurus kohlerorum
67.5-66 Ma Tremp Formation, Province of Lleida, Catalonia, Spain
  1. Kritosaurus navajovius
74-70 Ma, Campanian to Maastrichtian
  1. Kundurosaurus nagornyi
67-66 Ma Udurchukan Formation, Amur Oblast, Russia
  1. Lapampasaurus cholinoi
76-70 Ma, Campanian to Maastrichtian Allen Formation, La Pampa Province, Argentina
  1. Microhadrosaurus nanshiungensis
Nanxiong Formation, Guangdong, China
  1. Nanningosaurus dashiensis
  1. Olorotitan arhanensis
72-66 Ma A lambeosaurine characterized by numerous unique features for a hadrosaurid, the most obvious being the large hatchet-like crest adorning its skull. The skull itself is supported by a rather elongated neck, having 18 vertebrae, exceeding the previous hadrosaurid maximum of 15. The sacrum, with 15 or 16 vertebrae, has at least 3 more vertebrae than other hadrosaurids. Further along the vertebral series, in the proximal third of the tail, there are articulations between the tips of the neural spines, making that caudal area particularly rigid; the regularity of these connections suggests that they are not due to a pathology, although more specimens are needed to be certain. It is phylogenetically closest to Corythosaurus and Hypracosaurus.
  1. Orthomerus dolloi
  1. Pararhabdodon isonensis
67.5-66 Ma Tremp Formation, Province of Lleida, Catalonia, Spain
  1. Parksosaurus warreni
70 Ma Horseshoe Canyon Formation, Alberta, Canada A thescelosaurid that is one of the few non-hadrosaurid ornithopods from the end of the Cretaceous in North America.
  1. Rhabdodon priscus
  2. Rhabdodon septimanicus
70-66 Ma
  1. Sahaliyania elunchunorum
68-66 Ma
  1. Saurolophus angustirostris
  2. Saurolophus osborni
70-68.5 Nemegt Formation, Mongolia

Horseshoe Canyon Formation, Alberta, Canada

Distinguished by a spike-like crest which projects up and back from the skull.
  1. Secernosaurus koerneri
Argentina One of the few hadrosaurs to live in Gondwana and not Laurasia.
  1. Shantungosaurus giganteus
70 Ma Wangshi Group, Shandong, China So far the largest hadrosauroid in the world.
  1. Talenkauen santacrucensis
Pari Aike Formation, Santa Cruz Province, Argentina
  1. Telmatosaurus transsylvanicus
70-66 Ma Sanpetru Formation, Hunedoara County, Romania A relatively small hadrosaur, approximately 5 meters (16 ft) long. This is due to insular dwarfism on Hateg Island.
  1. Tethyshadros insularis
71-70 Ma Liburnia Formation, Province of Trieste, Friuli-Venezia Giulia, Italy A relatively small species of hadrosauroid due to insular dwarfism, just like with Telmatosaurus.
  1. Thescelosaurus garbanii
  2. Thescelosaurus neglectus
  3. Thescelosaurus assiniboiensis
66 Ma
  1. Thespesius occidentalis
66.5 Ma Lance Formation, South Dakota, USA
  1. Tsintaosaurus spinorhinus
70 Ma A lambeosaurine hadrosaur that was originally reconstructed with a unicorn-like crest of its skull. The crest, as preserved, consists of an about 40 centimeters long process, protruding almost vertically from the top of the rear snout. The structure is hollow and seems to have a forked upper end. Comparable structures with related species are unknown: they possess more lobe-like crests. Recently, a new reconstruction came to the conclusion that the unicorn-like bone was just the rear part of a larger cranial crest that started from the tip of the snout. The front of the crest would have been formed by ascending processes of the praemaxillae. These had expanded rhomboid contact facets with the expanded upper parts of the crest processes of the nasal bones, forming the rear of the crest. The rear base of the crest was covered by outgrowths of the prefrontals. The fused nasal bones would have formed a hollow tubular structure. The height of the crest would have exceeded that of the rear skull, measured along the quadrates. Though largely vertical, the crest is directed slightly to the rear; the forward inclination of the holotype crest would be the result of a distortion of the fossil.
  1. Velafrons
73-72 Ma, Campanian to Maastrichtian Cerro del Pueblo Formation, Coahuila, Mexico
  1. Willinakaqe salitralensis
Allen Formation, La Pamapa Province, Argentina
  1. Wulagasaurus dongi
66 Ma Yuliangze Formation, Heilongjiang, China
  1. Zalmoxes robustus
  2. Zalmoxes shqiperorum

Pachycephalosaurs[edit]

Pachycephalosaurs of the Maastrichtian
Taxa Presence Location Description Images
  1. Alaskacephale gangloffi
80-69 Ma, Campanian to Maastrichtian Prince Creek Formation, Alaska, USA Known from a nearly complete left squamosal with a characteristic array of polygonal nodes. The dimensions of this bone suggest that this genus was about half the size of Pachycephalosaurus or three quarters the size of Prenocephale prenes, and about the same size as Prenocepahle edmontonensis and Prenocephale brevis.
  1. Dracorex hogwartsia
66 Ma Hell Creek Formation, South Dakota, USA Named as a tribute to both dragons and the Harry Potter book series. Supposedly a synonymous younger form of Stygimoloch or Pachycephalosaurus.
  1. Pachycephalosaurus wyomingensis
70-66 Ma Hell Creek Formation, Montana, USA

Lance Formation, Montana, USA

  1. Prenocephale prenes
  2. Prenocephale brevis
  3. Prenocephale edmontonensis
  4. Prenocephale goodwini
83-66 Ma, Campanian to Maastrichtian Nemegt Formation, Mongolia

USA

  1. Sphaerotholus bucholtzae
  2. Sphaerotholus edmontonensis
  3. Sphaerotholus goodwini
80-66 Ma, Campanian to Maastrichtian Hell Creek Formation, Montana, USA

Horseshoe Canyon Formation, Alberta, Canada

This species had a widespread distribution and a characteristically dome-shaped skull.
  1. Stygimoloch spinifer
66 Ma Hell Creek Formation, Wyoming, USA

Ferris Formation, Wyoming, USA

  • Lance Formation, Wyoming, USA
Characterized by clusters of spikes on the back of the skull, in which a long central horn is surrounded by 2-3 small hornlets, and a tall, narrow dome. Some believe that it is a juvenile form of Pachycephalosaurus.
  1. Tylocephale gilmorei
80-70 Ma, Campanian to Maastrichtian Barun Goyot Formation, Mongolia This species has the tallest dome of any known pachycephalosaur.

Non-Avian Saurischians[edit]

Non-Avian Theropods[edit]

Non-avian theropods of the Maastrichtian
Taxa Presence Location Description Images
  1. Acheroraptor temertyorum
66 Ma Hell Creek Formation, Montana, USA A velociraptorine that was geologically the youngest known dromaeosaur.
  1. Adasaurus mongoliensis
70 Ma Nemegt Formation, Mongolia A dromaeosaurine dromaeosaur unique in having relatively small sickle claws on its hind feet.
  1. Ajancingenia yanshini
70 Ma Barun Goyot Formation, Mongolia Distinguished from all other oviraptorids by manual digit I subequal in length to digit II, and from all other oviraptorids except Nemegtomaia barsboldi by manual ungual I more than 100% larger than ungual II.
  1. Albertonykus borealis
68.5 Ma Horseshoe Canyon Formation, Alberta, Canada The earliest-known North American alvarezsaurid. It is interpreted as having fed on wood-nesting termites because the forelimbs appear to be specialized for digging, but are too short for burrowing.
  1. Albertosaurus sarcophagus
71-68 Ma Horseshoe Canyon Formation, Alberta, Canada A tyrannosaurid apparently restricted in range. Possibly had pack behavior.
  1. Alioramus remotus
70 Ma Nemegt Formation, Mongolia Characterized by a row of five bony crests along the top of the snout, a greater number of teeth than any other genus of tyrannosaurid, and a lower skull than other tyrannosaurids.
  1. Anserimimus planinychus
70 Ma Nemegt Formation, Mongolia An ornithomimid with more powerful forelimbs than other orinithomimids.
  1. Anzu wyliei
66 Ma Hell Creek Formation, Montana & South Dakota, USA

Marmarth, North Dakota

A caenagnathid, originally thought to be a species of Chirostenotes.
  1. Archaeornithomimus asiaticus
70 Ma Iren Dabasu Formation, Inner Mongolia, China An ornithomimid, originally thought to have lived from the Cenomanian to the Turonian.
  1. Atrociraptor marshalli
68.5 Ma Horseshoe Canyon Formation, Alberta, Canada A dromaeosaur that was originally thought to be a velociraptorine, now known to be a saurornitholestine.
  1. Austroraptor cabazai
70 Ma Allen Formation, Argentina The largest dromaeosaur to be discovered in the Southern Hemisphere.
  1. Avimimus portentosus
70 Ma Nemegt Formation, Mongolia An oviraptorosaur originally thought to be a bird.
  1. Bagaraatan ostromi
70 Ma Nemegt Formation, Mongolia An unspecified coelurosaur, theorized to be either a tyrannosaur or a maniraptoran.
  1. Balaur bondoc
70 Ma Sebes Formation, Romania Different from other paraves because it has not just one but two large, retractable, sickle-shaped claws on each hind foot, and its limbs are proportionally shorter and heavier than those of its relatives. It lived on Hateg Island.
  1. Banji long
66 Ma Nanxiong Formation, Jiangxi, China An oviraptorid, unique because the sides of its skull crest are adorned with a series of vertical striations, as well as grooves on the top of the lower jaw. It also differs from other oviraptorids in having an unusually long nasal opening that followed the curve of the crest nearly to the eye socket.
  1. Betasuchus bredai
66 Ma Netherlands One of the two abelisaurs to be found in the Northern Hemisphere, the other being Tarascosaurus.
  1. Borogovia gracilicrus
70 Ma Nemegt Formation, Mongolia A troodontid named after the fantasy birds called "borogoves" in the poem Jabberwocky from Lewis Carroll's Through the Looking-Glass.
  1. Bradycneme draculae
70 Ma Sanpetru Formation, Transylvania, Romania An alvarezsaurid, formerly believed to be a giant owl from a partial right lower leg. It came from Hateg Island.
  1. Carnotaurus sastrei
72-69.9 Ma La Colonia Formation, Chubut Province, Argentina An abelisaurid that was a highly specialized and distinctive theropod. It had thick horns above the eyes (a feature unseen in other known carnivorous theropods), a very deep skull sitting on a muscular neck. It is further characterized by small, vestigial forelimbs and long and slender hindlimbs. The skeleton is preserved with extensive skin impressions, showing a mosaic of small, non-overlapping scales measuring approximately 5 mm in diameter. The mosaic was interrupted by large bumps that lined the sides of the animal.
  1. Coeluroides
66 Ma Lameta Formation, India A small, little-known theropod that is estimated at 2 meters long and perhaps 30 kilograms in weight, similar to but larger than Jubbulpuria.
  1. Compsosuchus solus
69 Ma Lameta Formation, India An abelisaur that was probably really an allosaur.
  1. Deinocheirus mirificus
71-69 Ma Nemegt Formation, Mongolia A very large ornithomimosaur that was long thought of as a very mysterious dinosaur, known only from a set of gigantic fossil arm bones. The discovery of more complete skeletons helped to solve this longstanding mystery, revealing a very strange, giant, bipedal omnivore, resembling almost like a giant spoonbill with raised neural spines (which served as an attachment for ligaments which helped in keeping the animal upright, similar to a cable bridge).
  1. Dryptosauroides grandis
66 Ma Lameta Formation, India A mysterious ablelisaurid that is almost indistinguishable from the other theropods of the same region.
  1. Dryptosaurus aquilunguis
67 Ma A tyrannosaur that is among the first theropod dinosaurs known to science.
  1. Elmisaurus rarus
70 Ma Omnogovi Province, Mongolia A caenagnathid, once thought to be a Mongolian species of Chirostenotes.
  1. Elopteryx nopcsai
70 Ma A troodontid, originally believed to be a pelecaniform bird.
  1. Epichirostenotes curriei
72 Ma Horseshoe Canyon Formation, Alberta, Canada A caenagnathid originally thought to be the same species as Chirostenotes.
  1. Erliansaurus bellamanus
72-68 Ma Iren Dabasu Formation, Inner Mongolia, China For a therizinosaur, its neck was rather short.
  1. Euronychodon portucalensis
70 Ma A troodontid with teeth similar to those of Paronychodon.
  1. Gallimimus bullatus
70 Ma Nemegt Formation, Mongolia An ornithomimid that was one of the largest ornithomimosaurs.
  1. Ganzhousaurus nankangensis
Nanxiong Formation, Jiangxi, China An oviraptorid distinguished by a combination of primitive and derived features.
  1. Gigantoraptor erlianensis
70 Ma Iren Dabasu Formation, Inner Mongolia, China A caenagnathid that was the largest of any known oviraptorosaur.
  1. Heptasteornis andrewsi
67 Ma Sânpetru Formation, Romania An alvarezsaurid that was originally presumed to be a giant prehistoric owl, just like with Bradycneme.
  1. Heyuannia huangi
70 Ma Dalangshan Formation, China The first oviraptorid found in China.
  1. Indosaurus matleyi
69 Ma Lameta Formation, India Originally believed to be an allosaurid, now considered a majungasaurine abelisaurid.
  1. Indosuchus raptorius
70-66 Ma Lameta Formation, India A carnotaurine abelisaurid that is very similar to Indosaurus.
  1. Jiangxisaurus ganzhouensis
72-66 Ma Nanxiong Formation, Jiangxi, China An oviraptorid that was similar to Heyuannia, but with more strongly curved anterior claws and a thinner, frailer mandible.
  1. Jubbulpuria tenuis
70 Ma Lameta Formation, India A poorly-known theropod that may have been a ceratosaur.
  1. Laevisuchus indicus
70 Ma Lameta Formation, India Originally thought to be a coelurid coelurosaur. Recently however, it has been shown to be a noasaurid abelisaur.
  1. Lametasaurus indicus
70 Ma Lameta Formation, India A possibly dubious carnotaurine, originally indicated as a possible chimera.
  1. Leptorhynchos elegans
  2. Leptorhynchos gaddisi
75-66 Ma, Campanian to Maastrichtian Hell Creek Formation, Montana, USA

Aguja Formation, Texas, USA

Like many caenagnathids, it was once thought to be a species of Chirostenotes.
  1. Majungasaurus crenatissimus
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar A majungasaurine that was originally mistaken for a pachycephalosaur and called Majungatholus.
  1. Masiakasaurus knopfleri
70 Ma Maevarano Formation, Mahajanga Province, Madagascar Unlike most other theropods, the front teeth of this noasaurid project forward instead of straight down. This unique dentition suggests that it had a highly specialized diet, perhaps including freshwater fish and other small prey.
  1. Mononykus olecranus
70 Ma Nemegt Formation, Mongolia An alvarezsaurid that was a small non-avian theropod, only 1 meter (3.3 ft) long. Other characteristics include fused wrist bones similar to those of birds, and a keeled breastbone. It differs from other alvarezsaurids (like Shuvuuia and Parvicursor) in several details of its skeleton, including a pubic bone that is triangular in cross section, and different proportions in the toe bones.
  1. Nankangia jiangxiensis
Nanxiong Formation, Jiangxi, China
  1. Nanotyrannus lancensis
68.5-66 Ma May be a juvenile Tyrannosaurus or other tyrannosaurid.[1]
  1. Nanshiungosaurus brevispinus
78-70 Ma, Campanian to Maastrichtian Yuanpu Formation, Guangdong, China Distinguished from other therizinosaurids by the possession of twelve cervical vertebrae.
  1. Nanuqsaurus hoglundi
70-69.1 Ma Prince Creek Formation, Alaska, USA A tyrannosaurid estimated to have been about 6 meters (20 ft) long, about half the length of Tyrannosaurus. It lived in northernmost Laramidia, where it experienced cold weather and long periods of darkness and light, in addition to seasons in which prey availability increased and decreased depending on seasonal change.
  1. Nemegtomaia barsboldi
70 Ma Nemegt Formation, Mongolia
  1. Noasaurus leali
70 Ma Lecho Formation, Salta Province, Argentina A noasaurid originally thought to be a dromaeosaur.
  1. Nomingia gobiensis
70 Ma An oviraptorid characterized by a pygostyle-like mass of five fused vertebrae at the tail end, which probably supported a feather fan like Caudipteryx.
  1. Ojoraptorsaurus boerei
69 Ma Ojo Alamo Formation, New Mexico, USA A caenagnathid known from an incomplete pair of fused pubic bones.
  1. Orkoraptor burkei
70-66 Ma Pari Aike Formation, Argentina First thought to be a close relative of tyrannosaurs, now believed to be an allosaur.
  1. Ornithomimoides barasimlensis
  2. Ornithomimoides mobilis
70-66 Ma
  1. Ornithomimus edmontonicus
  2. Ornithomimus velox
75.5-66, Campanian to Maastrichtian
  1. Orthogoniosaurus matleyi
66 Ma Lameta Formation, India A poorly-known theropod, possibly an abelisaur.
  1. Paronychodon caperatus
66 Ma
  1. Pectinodon bakkeri
66 Ma Lance Formation, Wyoming, USA
  1. Pycnonemosaurus nevesi
70 Ma
  1. Pyroraptor olympius
70.6 Ma
  1. Qianzhousaurus sinensis
72-66 Ma Nanxiong Formation, Guangdong, China Nicknamed "Pinocchio rex" for its long snout in comparison to other known tyrannosaurs.
  1. Rahiolisaurus gujaratensis
72.1-66 Ma Lameta Formation, India
  1. Rahonavis ostromi
70 Ma Maevarano Formation, Mahajanga Province, Madagascar
  1. Rajasaurus narmadensis
69 Ma Lameta Formation, India
  1. Raptorex kriegsteini
70 Ma Mongolia, China
  1. Richardoestesia gilmorei
  2. Richardoestesia isosceles
76.5-66 Ma, Campanian to Maastrichtian
  1. Rinchenia mongoliensis
70 Ma Mongolia
  1. Saurornitholestes langstoni
77-69 Ma, Campanian to Maastrichtian
  1. Shixinggia oblita
70 Ma
  1. Struthiomimus altus
  2. Struthiomimus sedens
66 Ma Lance Formation, Wyoming, USA

Hell Creek Formation, Montana, USA

  • Horseshoe Canyon Formation, Alberta, Canada
  1. Tarbosaurus bataar
70 Ma Nemegt Formation, Mongolia
  1. Therizinosaurus cheloniformis
70 Ma Nemegt Formation, Mongolia One of the largest therizinosaurs. When its claw was first discovered, it was originally believed to be the rib of a giant turtle.
  1. Tochisaurus nemegtensis
69 Ma Nemegt Formation, Mongolia
  1. Troodon formosus
77-66 Ma, Campanian to Maastrichtian
  1. Tyrannosaurus rex
67-66 Ma Among the last large non-avian predatory theropods, as well as the largest known tyrannosaur.
  1. Variraptor mechinorum
70 Ma Gres a Reptiles Formation, France A dromaeosaur with some resemblances to Deinonychus. It may have been slightly smaller than Deinonychys, at around 2 meters (6.5 ft) long. Some believe it might be synonymous with Pyroraptor.
  1. Velociraptor mongoliensis
75-70 Ma, Campanian to Maastrichtian Djadochta Formation, Mongolia
  1. Vitakridrinda sulaimani
69 Ma Pab Formation, Pakistan
  1. Zanabazar junior
70 Ma Nemegt Formation, Mongolia A troodontid, originally classified as a species of Saurornithoides, now in a new genus named in honor Zanabazar, the first spiritual head of Tibetan Buddhism in Outer Mongolia.

Sauropods[edit]

Sauropods of the Maastrichtian
Taxa Presence Location Description Images
  • Alamosaurus sanjuanensis
70-66 Ma Ojo Alamo Formation, New Mexico, USA

North Horn Formation, Utah, USA

  • Ampelosaurus atacis
70-66 Ma Marnes Rouges Inferieures Formation, France Like most sauropods, this nemegtosaurid would have had a long neck and tail, but it also carried armor in the form of osteoderms 25-28 centimeters (9.8-11 in) long. The four osteoderms found have three different morphologies, they are plate, bulb, and spine-shaped.
  • Arkharavia heterocoelica
66 Ma Udurchukan Formation, Russia
  • Bruhathkayosaurus matleyi
70 Ma Kellemedu Formation, India A huge titanosaur that may be among the largest known dinosaurs. However, it might not be an animal at all, but instead a plant.
  • Campylodoniscus ameghinoi
95-70 Ma, Cenomanian to Maastrichtian Argentina
  • Dreadnoughtus schrani
76-66 Ma, Campanian to Maastrichtian Cerro Fortaleza Formation, Santa Cruz Province, Argentina A giant titanosaur that is one of the largest of all known terrestrial vertebrates, possessing the greatest mass of any land animal that can be calculated with reasonable certainty, using limb bone measurements.
  • Gondwanatitan faustoi
70 Ma Brazil
  • Hypselosaurus priscus
70-66 Ma Grès à Reptiles Formation, France
  • Isisaurus colberti
70 Ma Lameta Formation, India
  • Jainosaurus septentrionalis
68 Ma Lameta Formation, India
  • Magyarosaurus dacus
70-66 Ma Romania
  • Nemegtosaurus mongoliensis
  • Nemegtosaurus pachi
70 Ma Nemegt Formation, Mongolia
  • Opisthocoelocaudia skarzynskii
70 Ma Nemegt Formation, Mongolia
  • Puertasaurus reuili
70 Ma Patagonia, Argentina A lognkosaur that has the broadest sauropod vertebra known, and two-thirds of its width is made up of the huge wing-like diapophyses (side processes which supported the ribs), which are heavily buttresed and merge with both the centrum and the neural spine, forming a wide spade-like shape (in most sauropods, like Argentinosaurus, they are far less large, lack buttresses, and form a simple cross-bar shape).
  • Rapetosaurus krausei
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar A nemegtosaurid that was fairly modest in size, for a titanosaur, being less than half the length of Argentinosaurus and Paralititan.
  • Saltasaurus loricatus
70 Ma Argentina, Uruguay
  • Titanosaurus indicus
  • Titanosaurus blandfordi
70 Ma Lameta Formation, India
  • Uberabatitan ribeiroi
67 Ma Marilia Formation, Brazil
  • Vahiny depereti
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar A rare titanosaur coexisting with the more common Rapetosaurus. It is distinguished from other titanosaurs by characteristics of its braincase, including the basal tubera, basipterygoid processes, parasphenoid, and cranial nerve foramina. Differences in the braincases of Vahiny and Rapetosaurus indicate that they are not closely related to one another. Vahiny is most similar to Jainosaurus, and bears similarities to Muyelensaurus and Pitekunsaurus.

Birds (avian theropods)[edit]

Birds of the Maastrichtian
Taxa Presence Location Description Images
  • Anatalavis rex
66-65 Ma, Maastrichtian to Danian Hornerstown Formation, New Jersey, USA An ancient anseriform, possibly resembling the magpie-goose.
  • Avisaurus archibaldi
70.6-66 Ma Hell Creek, Montana, USA A genus of avisaurid enantiornithine that is known from the humid low-lying swamps, lakes and river basins of the western shore of the Western Interior Seaway.
  • Canadaga arctica
67 Ma Bylot Island, Nunavut, Canada A genus of hesperornithine that, unlike its relatives which are mainly known from subtropical or tropical waters, seemed to have ranged in temperate or even subarctic areas.
  • Ceramornis major
66 Ma Lance Formation, Wyoming, USA A charadriiform that might be mistaken for an anseriform.
  • Cimolopteryx maxima
  • Cimolopteryx rara
  • Cimolopteryx petra
Lance Formation, Wyoming, USA

Hell Creek Formation, Montana, USA

  • Elbertornis bonapartei
70 Ma Lecho Formation, Salta Province, Argentina
  • Enantiornis leali
70 Ma Argentina Among the largest enantiornithines discovered to date, having an ecological niche resembling that of a mid-sized accipitrid.
  • Gargantuavis philoinos
70 Ma Marnes Rouges Inferieures Formation, France A large flightless euornithine bird that occupied an ecological niche somewhat similar to that of modern ratites or certain non-avian dinosaurs. Its eggs were previously attributed to titanosaurs.
  • Graculavus augustus
68 Ma Lance Formation, Wyoming, USA A charadriiform that lived on the shores of the northwestern Atlantic and the Western Interior Seaway.
  • Gurilynia nessovi
70-66 Ma Nemegt Formation, Mongolia
  • Hesperornis crassipes
  • Hesperornis gracilis
  • Hesperornis montana
  • Hesperornis regalis
  • Hesperornis rossicus
99.7-66.043 Ma, Cenomanian to Maastrichtian USA, Canada, Russia A hesperornithine that lived in the waters of such contemporary shallow shelf seas as the Western Interior Seaway, the Turgai Strait, and the prehistoric North Sea, which then were subtropical to tropical waters, much warmer than to today. It had virtually no wings, and swam with its powerful hind legs. The toes were probably lobed, as in grebes, rather than webbed as in those of loons. It was a very typical hesperornithine.
  • Judinornis nogontsavensis
70 Ma Nemegt Formation, Mongolia A basal hesperornithine that, unlike its relatives, apparently lived in estuaries and rivers from the mountains thrown up by the Cimmerian Orogeny through the arid lands of continental East Asia towards the Turgai Sea and the former Shigatze Ocean.
  • Laornis edvardsianus
66-63 Ma, Maastrichtian to Danian Hornerstown Formation, New Jersey, USA
  • Lectavis bretincola
70.6-66 Ma Lecho formation, Salta Province, Argentina A genus of wading birds with uncertain evolutionary affinities, it had legs resembling and a body approximately the size of a modern curlew. The only known Lectavis species, it lived in Argentina
  • Neogaeornis wetzeli
70-67 Ma Quiriquina Formation, Quiriquina Island, Chile A marine bird from Chile. It had the midfeet of a foot-propelled diving bird, but its relationships are enigmatic. The only known species is from the Campanian-Maastrichitan boundary.
  • Palintropus retusus
66 Ma Lance Formation, Wyoming, USA A poorly-known bird that is sometimes believed to be an early charadriiform or galliform. It is now primarily known to be an ambiortiform.
  • Potamornis skutchi
66 Ma Lance Formation, Wyoming, USA A hesperornithine that has a unique quadrate bone in some respects but apparently shares more apomorphies with "typical" hesperornithines. Consequently, Consequently, it might be considered a fossil hesperornithid with a different feeding specialization. Though it was heavily built like many (flying and flightless) diving birds, it weighed perhaps 1.5 or 2 kg.
  • Soroavisaurus australis
70 Ma Lecho Formation, Salta Province, Argentina
  • Telmatornis priscus
71-68 Ma Navesink Formation, New Jersey, USA
  • Teviornis gobiensis
70 Ma Nemegt Formation, Mongolia
  • Tytthostonyx glauconiticus
66 Ma Hornerstown Formation, New Jersey, USA
  • Vegavis iaai
66 Ma Vega Island, Antarctica
  • Vorona berivotrensis
83.5-70 Ma, Campanian to Maastrichtian Maevarano Formation, Mahajanga Province, Madagascar A euornithine sometimes confused with Rahonavis, a confusion that has lead to the common misconception that Vorona had a dromaeosaur-like sickle claw on each foot.

Cartilaginous fish[edit]

Cartilaginous Fish of the Maastrichtian
Taxa Presence Location Description Images
Turonian to Ypresian
100-0 Ma, Cenomanian to present
70-0 Ma, Maastrichtian to present
  1. Rhombodus binkhorsti
  2. Rhombodus levis
  1. Squalicorax kaupi
  2. Squalicorax pristodontus

Crocodylomorphs[edit]

Crocodylomorphs of the Maastrichtian
Taxa Presence Location Description Images
  1. Allodaposuchus precedens
  2. Allodaposuchus subjuniperus
Campanian to Maastrichtian An average-sized eusuchian, growing to around 3 meters (9.8 ft) long. The main feature that distinguishes this species from other related crocodylomorphs is the orientation of a groove at the back of the skull called the cranioquadrate passage; unlike the cranioquadrate passages of other crocodylomorphs, which are only visible at the back of the skull, the cranioquadrate passage of this variety is visible when the skull is viewed from the side.
  1. Araripesuchus tsangatsangana
Maevarano Formation, Mahajanga Province, Madagascar A uruguaysuchid that can be distinguished by their laterally bulged edges of the snout, with the bulge being the most prominent around the area of an enlarged maxillary tooth.
  1. Borealosuchus sternbergii
Colorado, Montana, North Dakota, South Dakota, Wyoming
Maastrichtian to Danian New Jersey, Alabama, South Carolina
  1. Itasuchus jesuinoi
70.6-65.5 Ma Marilia Formation, Minas Gerais, Brazil
  1. Labidiosuchus amicum
Marilia Formation, Minas Gerais, Brazil
  1. Mahajangasuchus insignis
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar
A notosuchian from Brazil. May have had a pig like diet and was almost certainly warm blooded.
  1. Miadanasuchus oblita
Maevarano Formation, Mahajanga Province, Madagascar
  1. Pabwehshi pakistanensis
Pab Formation, Balochistan, Pakistan
  1. Peirosaurus torminni
68-66 Ma Marilia Formation, Minas Gerais, Brazil
  1. Pepesuchus deiseae
Campanian to Maastrichtian
  1. Pissarrachampsa sera
Campanian to Maastrichtian Vale do Rio do Peixe Formation, Sao Paulo, Brazil
85-66 Ma, Santonian to Maastrichtian
  1. Simosuchus clarki
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar A notosuchian which had teeth shapes like cloves, which coupled with its short and deep snout suggest it was not a carnivore like most other crocodylomorphs. In fact, these features have led many to consider it a herbivore.
  1. Stratiotosuchus maxhechti
Campanian to Maastricthian
  1. Theriosuchus sympiestodon
  1. Uberabasuchus terrificus
85-66 Ma, Santonian to Maastrichtian

Bony fish[edit]

Bony Fish of the Maastrichtian
Taxa Presence Location Description Images
  • Coriops amnicolus
Hell Creek Formation, Montana, USA

Mammals[edit]

Mammals of the Maastrichtian
Taxa Presence Location Description Images
  1. Argentodites coloniensis
La Colonia Formation, Chubut Province, Argentina It is debated whether this is a multituberculate or a gondwanathere.
  1. Bharattherium jederi
  1. Cimolestes incisus
75-56 Ma, Campanian to Danian
  1. Didelphodon coyi
  2. Didelphodon padanicus
  3. Didelphodon vorax
73-66 Ma, Campanian to Maastrichtian Hell Creek Formation, Montana, USA

Lance Formation, Wyoming, UA

  • Scollard Formation, Alberta, Canada
A stagodont metathere that was one of the largest Mesozoic mammals.
  1. Ferugliotherium windhauseni
70 Ma
  1. Lavanify miolaka
71-66 Ma Maevarano Formation, Mahajanga Province, Madagascar
  1. Nanocuris improvida
Saskatchewan, Canada

Wyoming, USA

66-63 Ma, Maastrichtian to Danian Montana, USA Believed to be the earliest primate or a primatomorph.
  1. Reigitherium bunodontum
Campanian to Maastrichtian Los Alamitos Formation, Rio Negro Province, Argentina

La Colonia Formation, Chubut Province, Argentina

At first mistaken for either a dryolestid or a docodont, now known to be a meridiolestid dryolestoid.
  1. Trapalcotherium matuastensis
Allen Formation, Argentina
  1. Vintana sertichi
66 Ma Madagascar
  1. Zalambdalestes lechei
Mongolia A shrew-like eutherian that was perhaps placental.

Plesiosaurs[edit]

Plesiosaurs of the Maastrichtian
Taxa Presence Location Description Images
  • Fresnosaurus drescheri
California, USA An elasmosaurid named in honor of Fresno County and Arthur Drescher.
  • Hydrotherosaurus alexandrae
  • Kaiwhekea katiki
70-69 Ma Katiki Formation, Otago, South Island, New Zealand
  • Leurospondylus ultimus
Horseshoe Canyon Formation, Alberta, Canada A little-known plesiosaur, probably either an elasmosaurid or a late-surviving plesiosaurid. Offspring most likely spent their early lives in brackish rivers and estuaries.
  • Mauisaurus haasti
80-69 Ma, Campanian to Maastrichtian Canterbury, South Island, New Zealand The largest plesiosaur, and perhaps the largest marine reptile in New Zealand waters at the time.
  • Zarafasaura oceanis
Ouled Abdoun Basin, Morocco

Pterosaurs[edit]

Pterosaurs of the Maastrichtian
Taxa Presence Location Description Images
  1. Aerotitan sudamericanus
Allen Formation, Argentina
  1. Arambourgiania philadelphiae
Jordan
  1. Eurazhdarcho langendorfensis
Sebes Formation, Romania A medium-sized azhdarchid (having an estimated wingspan of three meters) with some distinctive traits, all present in the cervical vertebrae.
  1. Hatzegopteryx thambema
70-66 Ma Densus-Ciula Formation, Romania An azhdarchid, indicated to be among the largest of pterosaurs.
  1. P. mauritanicus
66 Ma Oulad (or Qualad) Abdoun Phosphatic Basin, Grand Doui, near Khouribga, central Morocco The first azhdarchid found in North Africa, as well as being unusual among azhdarchids for having elongate vertebrae at the base of the neck (also with neural spines), interpreted as modified dorsal vertebrae.
  1. Quetzalcoatlus northropi
68-66 Ma Hell Creek Formation, Montana, USA

Javelina Formation, Texas, USA

An azhdarchid from North America that was one of the largest pterosaurs to ever live.

Squamates[edit]

Squamates of the Maastrichtian
Taxa Presence Location Description Images
  • Carinodens belgicus
100-66 Ma, Cenomanian to Maastrichtian Slovenia
  1. Ectenosaurus clidastoides
100-66 Ma, Cenomanian to Maastrichtian Kansas, Texas
  1. Eidolosaurus trauthi
100-66 Ma, Cenomanian to Maastrichtian Slovenia
  1. Eremiasaurus heterodontus
Morocco
  1. Goronyosaurus nigeriensis
  1. Hainosaurus bernardi
70.6-66 Ma
  1. Halisaurus platyspondylus
With a length of 3-4 m (10-13 ft), this species of halisaurine is small compared to most other mosasaurs.
  1. Igdamanosaurus aegyptiacus
  1. Kelyophis hechti
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar
  1. Komensaurus carrolli
100-66 Ma, Cenomanian to Maastrichtian Slovenia
  1. Liodon sectorius
  1. Madtsoia madagascariensis
  2. Madtsoia pisdurensis
Campanian to Maastrichtian Madagascar

India

  1. Menarana nosymena
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar
  1. Moanasaurus mangahouangae
North Island, New Zealand A mosasaurine that was one of the largest of the mosasaurs.
  1. Mosasaurus dekayi
  2. Mosasaurus hoffmanni
  3. Mosasaurus mokoroa
70-66 Ma
  1. Nedophis insularis
Romania
  1. Plesiotylosaurus crassidens
  1. Plotosaurus tuckeri
A mosasaurine that was probably a faster swimmer than most other mosasaurs.
  1. Prognathodon waiparaensis
  1. Sanajeh indicus
68 Ma Lameta Formation, India A snake that is known to eat the eggs and hatchlings of dinosaurs.
  1. Vallecillosaurus donrobertoi
100-66 Ma, Cenomanian to Maastrichtian Nuevo Leon, Mexico

Turtles[edit]

Testudines of the Maastrichtian
Taxa Presence Location Description Images
USA
Jordan A sea turtle that was one of the largest sea turtles ever.
  • Kurmademys kallamedensis
70.6-66 Ma Kallamedu Formation, India
  • Palatobaena bairdi
  • Palatobaena cohen
70.6-66 MA Fort Union Formation, Wyoming, USA

Hell Creek Formation, North Dakota, USA

  • Patagoniaemys gasparinae
Campanian to Maastrichtian La Colonia Formation, Chubut Province, Argentina A little-known basal turtle.
  • Peckemys brinkman
Hell Creek Formation, USA
  • Pneumatoarthrus peloreus
Kansas, USA A protostegid sea turtle that was at first mistakenly believed to be a hadrosaur by Edward Drinker Cope.

References[edit]

  1. ^ Henderson (2005). "Nano No More: The death of the pygmy tyrant." In "The origin, systematics, and paleobiology of Tyrannosauridae”, a symposium hosted jointly by Burpee Museum of Natural History and Northern Illinois University.

See also[edit]

Cretaceous Period
Lower/Early Cretaceous Upper/Late Cretaceous
Berriasian | Valanginian | Hauterivian
Barremian| Aptian | Albian
Cenomanian | Turonian | Coniacian
Santonian |Campanian | Maastrichtian