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 Selandian 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

An ankylosaurine ankylosaurid that was the largest known ankylosaur.
  • Anodontosaurus lambei
72.8-67 Ma, Campanian to Maastrichtian Horseshoe Canyon Formation, Alberta, Canada
  • Antarctopelta oliveroi
74-70 Ma, Campanian to Maastrichtian Santa Marta Formation, James Ross Island, Antarctica An ankylosaur with characteristics of both polacanthids and nodosaurs, making its precise classification difficult. It was the first dinosaur to be discovered in Antarctica, although it is the second dinosaur from the continent to be formally named.
  • 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 nodosaur at roughly 6.6 meters (22 ft) long and 2 meters (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 A struthiosaurine nodosaur that is one of the smallest known and most basal genera of nodosaurs from the Late Cretaceous. Although estimates of its length vary, it may have been as small as 2.2 meters (7.2 ft) long.
  • Tarchia kailanae
84.9-70.6 Ma, Santonian to Maastrichtian Barun Goyot Formation, Mongolia An ankylosaurine ankylosaurid that is currently the geologically youngest known of all Asian ankylosaurs.

Ceratopsians[edit]

Ceratopsians of the Maastrichtian
Taxa Presence Location Description Images
  1. Agathaumas sylvestris
66 Ma Lance Formation, Wyoming, USA A chasmosaurine ceratopsid that was the first ceratopsian known to science, though relatively little is known about it. The original specimen consisted only of the animal's hip bones, hip vertebrae and ribs, and because these bones vary little between ceratopsid species, it is usually considered a nomen dubium. It is provisionally considered a synonym of Triceratops, but is difficult to compare to that genus because it is only known from post-cranial remains.
  1. Anchiceratops ornatus
72-71 Ma St. Mary River Formation, Alberta, Canada A chasmosaurine ceratopsid with a very distinctive frill. Rectangular in shape, the frill is edged by large epoccipitals. These are exceptionally wide and coarse.
  1. Arrhinoceratops brachyops
70.6-70 Ma Horseshoe Canyon Formation, Alberta, Canada A chasmosaurine ceratopsid known only from its skull. The skull, as restored, features a broad, square, neck frill with two oval shaped openings. The frill is deeply veined on both the top and the underside by arterial grooves. The sides of the frill are adorned by about nine osteoderms. The rear edge of the frill is lightly scalloped. Its brow horns were moderately long, but its nose horn was shorter and blunter than most other ceratopsids. The snout is short and high.
  1. Bravoceratops polyphemus
70 Ma Javelina Formation, Texas, USA A rare chasmosaurine ceratopsid that analysis suggests may be the sister species of Coahuilaceratops, however this relationship is not well supported as there are very few elements available for a direct comparison of these two species.
  1. Coahuilaceratops magnacuerna
72.5-71.4 Ma, Campanian to Maastrichtian Cerro del Pueblo Formation, Coahuila, Mexico A chasmosaurine ceratopsid 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 ceratopsid 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. Lamaceratops tereschenkoi
84.9-70.6 Ma, Santonian to Maastrichtian Barun Goyot Formation, Omnogovi Province, Mongolia It is debated whether this is a bagaceratopsid or a protoceratopsid.
  1. Leptoceratops gracilis
66.8-66 Ma Hell Creek Formation, Montana, USA

Lance Formation, Alberta, Canada

  • Scollard Formation, Alberta, Canada
A leptoceratopsid that could probably stand and run on its hind legs. Analysis of forelimb function indicates that even though it could not pronate its hands, it could also walk on all four legs.
  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 chasmosaurine 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 chasmosaurine 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 A widespread, migratory centrosaurine ceratopsid. Instead of horns, their skulls bore massive, flattened bosses; a large boss over the nose and a smaller one over the eyes. A prominent pair of horns grew from the frill and extended upwards. The skull also bore several smaller horns or ornaments that varied between individuals and between species. In P. canadensis and P. perotorum, the bosses over the nose and eyes nearly grew together, and were separated only by a narrow groove. In P. lakustai, the two bosses were separated by a wide gap. In P. canadensis and P. lakustai, the frill bore two additional small, curved, backward-pointed horns. These were not present in P. perotorum, and in fact some specimens of P. lakustai also lack them, which may indicate that the presence of these horns varied by age and/or sex.
  1. Platyceratops tatarinovi
75-71 Ma, Campanian to Maastrichtian Barun Goyot Formation, Omnogovi Province, Mongolia A bagaceratopsid with a larger skull than Bagaceratops. Few believe that they were the same species.
  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

A protoceratopsid partially characterized by its distinctive neck frill. The frill itself contained two large parietal fenestra, while its cheeks had large jugal bones. The exact size and shape of the neck frill varied by individual; some specimens had short, compact frills, while others had frills nearly half the length of the skull. The frill consists mostly of the parietal bone and partially of the squamosal. This is attributed to both sexual dimorphism and age of the specimen. Ancient Scythian nomads once mistook some of the species remains for those of a griffin.
  1. Sinoceratops zhuchengensis
72-66 Ma Xingezhuang Formation, Shandong, China The first 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 ceratopsid, 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 A lambeosaurine hadrosaur characterized by many unique features of the skull, as well as the sigmoidal shape of the ulna when viewed from the front or side. Most other known lambeosaurines have hollow crests on the top of their skulls, and although the bones that would make up such a crest are unknown in this dinosaur, the bones of the roof of the skull are modified to support one, so it can be assumed that Amurosaurus was crested as well.
  1. Arenysaurus ardevoli
66 Ma Spain A lambeosaurine hadrosaur that is one of the most complete and best dated ever found in the Late Cretaceous period.
  1. Bactrosaurus johnsoni
70 Ma Iren Dabasu Formation, Inner Mongolia, China One of the best known early hadrosauroids from the Late Cretaceous.
  1. Barsboldia sicinskii
70 Ma Nemegt Formation, Omnogovi Province, Mongolia A hadrosaur originally described as a lambeosaurine, now believed to instead be a saurolophine.
  1. Blasisaurus canudoi
66 Ma Aren Formation, Spain A medium-sized lambeosaurine hadrosaur with two distinct features: the cheekbone has a rear projection with a hook-shaped upper edge, and the lower sleep window is narrow and D-shaped. From the same formation is the related Arenysaurus. They are not identical, distinguished by the shape of the teeth and missing secondary ridges. It also differs from Koutalisaurus by a downwardly bent front edge of the lower jaws.
  1. Canardia garonnensis
67.5-66 Ma Marnes d'Auzas Formation, France
  1. Charonosaurus jiayinensis
66 Ma Yuliangze Formation, Heilongjiang, China A lambeosaurine hadrosaur appearing similar in skull shape to Parasaurolophus
  1. Edmontosaurus regalis
  2. Edmontosaurus annectens
73-66 Ma, Campanian to Maastrichtian USA, Canada A well-known genus of saurolophine hadrosaur. 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. Huaxiaosaurus aigahtens
70 Ma Xingzhuang Formation, Shandong, China A large saurolophine hadrosaur, some of its estimated dimensions include a length of 18.7 meters (61 ft) and a height of 11.3 meters (37 ft) (in a tripodal posture) makes it one of the largest ornithopods known.
  1. Hypacrosaurus altispinus
75-67 Ma, Campanian to Maastrichtian Horseshoe Canyon Formation, Alberta, Canada A lambeosaurine hadrosaur 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 hadrosaur 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
Maastricht Formation, Limburg, Netherlands

Belgium

An obscure genus of hadrosaur. In the past it was conflated with the much better known Telmatosaurus.
  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 Romania, Spain, France, Czech Republic A rhabdodontid that was probably an important herbivore in Cretaceous Europe. Its predators may include potentially dubious northern abelisaurids, and young may have been prey for Pyroraptor.
  1. Sahaliyania elunchunorum
68-66 Ma
  1. Saurolophus angustirostris
  2. Saurolophus osborni
70-68.5 Nemegt Formation, Mongolia

Horseshoe Canyon Formation, Alberta, Canada

A saurolophine hadrosaur distinguished by a spike-like crest which projects up and back from the skull.
  1. Secernosaurus koerneri
Argentina A saurolophine hadrosaur that is one of the few hadrosaurs to live in Gondwana and not Laurasia.
  1. Shantungosaurus giganteus
70 Ma Wangshi Group, Shandong, China A saurolophine hadrosaur that is, 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. Goyocephale lattimorei
85.8-66 Ma, Santonian to Maastrichtian Mongolia Formally described from an incomplete skull, mandibles, and fragmentary postcranial material. The skull is nearly the same size as that of Prenocephale and Homalocephale.
  1. Pachycephalosaurus wyomingensis
70-66 Ma Hell Creek Formation, Montana, USA

Lance Formation, Montana, USA

The largest known pachycephalosaur.
  1. Prenocephale prenes
  2. Prenocephale brevis
  3. Prenocephale edmontonensis
  4. Prenocephale goodwini
83-66 Ma, Campanian to Maastrichtian Nemegt Formation, Mongolia A similar species to Homalocephale. However, unlike the flattened wedge-shaped skull of Homalocephale (a possible juvenile trait also potentially seen in early growth stages of Pachycephalosaurus), the head of Prenocephale was rounded and sloping. The dome had a row of small bony spikes and bumps. It lived in high upland forests.
  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 A unenlagiine that was 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 Maastricht Formation, Limburg, Netherlands One of the three abelisaurs to be found in the Northern Hemisphere, the others being Tarascosaurus and Arcovenator.
  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. Diplotomodon horrificus
70 Ma Navesink Formation, New Jersey, USA A dubious tyrannosauroid that was originally mistaken for a fish because of its teeth. It might be a synonym of Dryptosaurus.
  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, Guangdong, 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, Madhya Pradesh, 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, Madhya Pradesh, India A poorly-known theropod that may have been a ceratosaur.
  1. Laevisuchus indicus
70 Ma Lameta Formation, Madhya Pradesh, 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, Madhya Pradesh, India A possibly dubious carnotaurine abelisaurid, originally indicated as a possible chimera.
  1. Luanchuanraptor henanensis
99.7-66.043 Ma, Cenomanian to Maastrichtian Qiupa Formation, Henan, China A moderately-sized dromaeosaur, and the first Asian dromaeosaurid described from outside the Gobi Desert or northeastern China.
  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 abelisaurid 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 A caenagnathoid oviraptorosaur that had relatively short dentary and non-downturned mandibular symphysis. This suggests that it may have been a mostly herbivorous omnivore.
  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 It is debated whether this is a tyrannosaur or a late surviving allosaur.
  1. Ornithomimoides barasimlensis
  2. Ornithomimoides mobilis
70-66 Ma A dubious theropod that was probably a small variety of abelisaur.
  1. Ornithomimus edmontonicus
  2. Ornithomimus velox
75.5-66, Campanian to Maastrichtian
  1. Orthogoniosaurus matleyi
66 Ma Lameta Formation, Madhya Pradesh, India A poorly-known theropod, possibly an abelisaur.
  1. Paronychodon caperatus
66 Ma
  1. Pectinodon bakkeri
66 Ma Lance Formation, Wyoming, USA A troodontid that has been historically considered synonymous with Troodon, now a valid genus.
  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. Qiupalong henanensis
99.7-66.043 Ma, Cenomanian to Maastrichtian Qiupa Formation, Henan, China The first definitive Asian ornithomimid from outside of the Gobi Desert and is the southern-most occurrence of Late Cretaceous ornithomimidae from eastern Asia.
  1. Quilmesaurus curriei
Campanian to Maastrichtian Allen Formation, Neuquén Province, Argentina A carnotaurine abelisaurid that was originally found to be distinguished by unique features of the leg: a well developed mesiodistal crest on the femur; a hooked cnemial crest on the tibia; a asymmetrical distal tibia end; and possessing a later maleolus two times larger than the medial malleolus.
  1. Rahiolisaurus gujaratensis
72.1-66 Ma Lameta Formation, Gujarat, India
  1. Rahonavis ostromi
70 Ma Maevarano Formation, Mahajanga Province, Madagascar A small unenlagiine dromaeosaur that probably glided a bit like Microraptor. It was once believed to be a type of bird, but it was later found to be a dromaeosaur closely related to Unenlagia and Buitreraptor.
  1. Rajasaurus narmadensis
69 Ma Lameta Formation, Gujarat, India A majungasaurine abelisaurid with an unusual head crest.
  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
75-66 Ma, Campanian to Maastrichtian Lance Formation, Wyoming, USA

Hell Creek Formation, Montana, USA

  • Horseshoe Canyon Formation, Alberta, Canada
An ornithomimid that differs from close relatives only in subtle aspects of anatomy. The edge of the upper beak was concave, unlike Ornithomimus, which had straight beak edges. It had longer hands relative to the humerus than other ornithomimids, with particularly long claws. Their forelimbs were more robust than in the similar Ornithomimus.
  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 A widespread troodontine troodontid that had one of the largest known brains of any dinosaur group, relative to their body mass (comparable to modern birds).
  1. Tyrannosaurus rex
68-66 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. Yulong mini
99.7-66.043 Ma, Cenomanian to Maastrichtian Qiupa Formation, Henan, China One of the smallest known oviraptorids.
  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
84-66 Ma, Santonian 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 An aeolosaurid titanosaur that had elongated centra in the vertebrae from the middle part of its tail. It had vertebral lateral fossae that resembled shallow depressions, similar to Saltasaurus, Alamosaurus, Malawisaurus and Aeolosaurus.
  • Hypselosaurus priscus
70-66 Ma Grès à Reptiles Formation, France
  • Isisaurus colberti
70 Ma Lameta Formation, Maharashtra, India An antarctosaurid that had a "bizarre" appearance with a short, vertically directed neck and long forelimbs, making it considerably different from other sauropods.
  • Jainosaurus septentrionalis
68 Ma Lameta Formation, Madhya Pradesh, India
  • Loricosaurus noricus
71 Ma Allen Formation, Neuquén Province, Argentina A saltasaurine saltasaurid that, due to the presence of armor, was first thought to be an ankylosaur.
  • Magyarosaurus dacus
70-66 Ma Romania
  • Nemegtosaurus mongoliensis
  • Nemegtosaurus pachi
70 Ma Nemegt Formation, Mongolia A nemegtosaurid with a skull resembling that of a diplodocoid in being long and low, with pencil-shaped teeth.
  • Neuquensaurus australis
  • Neuquensaurus robustus
71 Ma Anacleto Formation, Neuquén Province, Argentina

Uruguay

  • Opisthocoelocaudia skarzynskii
70 Ma Nemegt Formation, Mongolia
  • Puertasaurus reuili
70 Ma 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).
  • Quaesitosaurus orientalis
85-70 Ma, Santonian to Maastrichtian Barun Goyot Formation, Omnogovi Province, Mongolia A little-known nemegtosaurid. Its fossils consist solely of a partial skull. Long, low and horse-like with frontally located peg-like teeth, it is similar enough to the skulls of Diplodocus and its kin to have prompted informed speculation that the missing body was formed like those of diplodocids. It is possible that Nemegtosaurus, also known from only skull material, is a very close relative of Quaesitosaurus, if not indeed a variation of the same animal.
  • 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.
  • Asiahesperornis bazhanovi
70 Ma Kazakhstan A hesperornithine that lived on the shores of the shallow Turgai Sea.
  • Avisaurus archibaldi
  • Avisaurus gloriae
70.6-66 Ma Hell Creek Formation, 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

A fairly small charadriiform, with a maximum size about equal to that of a small gull.
  • 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 euenantiornithine with uncertain evolutionary affinities, it had legs resembling and a body approximately the size of a modern curlew.
75-70 Ma, Campanian to Maastrichtian
  • 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
68-66 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.
  • Yungavolucris brevipedalis
70.6-66 Ma Lecho Formation, Salta Province, Argentina A little-known euenantiornithine that is sometimes considered to be closely related to Avisaurus. This is quite unlikely however; it certainly lacks the backwards-projecting growth of the trochlea where the middle toe attaches that is typical for avisaurids. Moreover, as opposed to the undisputed avisaurids which apparently all were fairly large carnivores, it was a much smaller animal and almost certainly did not hunt other vertebrates.

Cartilaginous fish[edit]

Cartilaginous Fish of the Maastrichtian
Taxa Presence Location Description Images
  1. Coupatezia trempina
A genus of myliobatiform ray that survived into the Lutetian.
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 A medium-sized crocodilian genus that lived into the Eocene.
  1. Chenanisuchus lateroculi
Maastrichtian to Danian Mali, Morocco A dyrosaurid with the shortest snout relative to the dorsal skull length among all dyrosaurids.
Maastrichtian to Danian New Jersey, Alabama, South Carolina
  1. Itasuchus jesuinoi
70.6-66 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
  1. Rhabdognathus aslerensis
  2. Rhabdognathus keiniensis
70.6-55.8 Ma, Maastritchtian to Ypresian Nigeria, Mali
  1. Shamosuchus ancestralis
  2. Shamosuchus djadochtaensis
  3. Shamosuchus tersus
  4. Shamosuchus ulanicus
85-66 Ma, Santonian to Maastrichtian Mongolia, China A paralligatorid with teeth adapted to crush bivalves, gastropods and other smaller animals with a hard shell or exoskeleton. The eye and nasal openings were not raised above the skull as in modern crocodilians, so that the animal would have to raise its head completely out of the water to breathe. As this cranial morphology does not suit an ambush predator, it lends support to the idea of a diet of aquatic invertebrates.
  1. Simosuchus clarki
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar A ziphosuchian 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. Thoracosaurus borissiaki
  2. Thoracosaurus isorhynchus
  3. Thoracosaurus macrorhynchus
  4. Thoracosaurus neocesariensis
  5. Thoracosaurus pneumaticus
70.6-50.3 Ma, Maastrichtian to Ypresian
  1. Uberabasuchus terrificus
85-66 Ma, Santonian to Maastrichtian Marilia Formation, Minas Gerais, Brazil A peirosaurid that was about 2.5 m long and appears to have a high skull like that of the sebecosuchians, but differs from them in having teeth with circular cross-section. Thus, rather than slicing flesh and blood vessels, it is likely to have inflicted powerful crushing bites. It lived in an arid climate, indicating that it was likely a terrestrial predator.

Bony fish[edit]

Bony Fish of the Maastrichtian
Taxa Presence Location Description Images
  • Coriops amnicolus
Hell Creek Formation, Montana, USA
  • Xiphactinus audax
  • Xiphactinus vetus
94.3-66 Ma, Cenomanian to Maastrichtian

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. Barbatodon oardaensis
  2. Barbatodon transylvanicum
  3. Barbatodon ungureanui
Sanpetru Formation, Hunedoara County, Romania A small and very rare kogaionid multituberculate.
  1. Bharattherium jederi
Intertrappean Beds, Telangana, India
  1. Cimolestes incisus
75-56 Ma, Campanian to Thanetian
  1. Deccanolestes hislopi
  2. Deccanolestes robustus
Intertrappean Beds, Andhra Pradesh, India Previously referred to as a palaeoryctid, but recent evidence has shown the it is either the most basal euarchontan, probably more specifically an adapisoriculid.
  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. Gondwanatherium patagonicum
84.9-66 Ma, Santonian to Maastrichtian Los Alamitos Formation, Rio Negro Province, Argentina A sudamericid that, even though it lived earlier than Sudamerica, is considered more anatomically advanced. Thus, an ancestral lineage outlived their later, more specialized descendants.
  1. Kharmerungulatum vanvaleni
Intertrappean Beds, Andhra Pradesh, India One of the earliest known condylarths.
  1. Kimbetohia campi
66-63 Ma, Maastrichtian to Danian Nacimiento Formation, New Mexico, USA
  1. Kogaionon ungureanui
Sanpetru Formation, Hunedoara County, Romania A kogaionid that was a micro-mammal, based on a well-preserved skull.
  1. Lavanify miolaka
71-66 Ma Maevarano Formation, Mahajanga Province, Madagascar
  1. Nanocuris improvida
Saskatchewan, Canada

Wyoming, USA

  1. Purgatorius janisae
  2. Purgatorius titusi
  3. Purgatorius unio
66.043-63.3 Ma, Maastrichtian to Danian Hell Creek Formation, Montana, USA

Tullock Formation, Montana, USA

An early plesiadapiform, closely related to true primates.
  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. Sahnitherium rangapurensis
Intertrappean Beds, Andhra Pradesh, India
  1. Trapalcotherium matuastensis
Allen Formation, Argentina
  1. Vintana sertichi
66 Ma Madagascar A caviomorph-like sudamericid with supersensory capabilities.
  1. Zalambdalestes lechei
Mongolia A shrew-like eutherian that was perhaps placental.

Plesiosaurs[edit]

Plesiosaurs of the Maastrichtian
Taxa Presence Location Description Images
  • Aristonectes parvidens
  • Aristonectes quiriquiensis
70-66 Ma Quiriquina Formation, Quiriquina Island, Chile

Antarctica

  • Dolichorhynchops herschelensis
73-70.6 Ma, Campanian to Maastrichtian Bearpaw Formation, Saskatchewan, Canada
  • Fresnosaurus drescheri
70.6-66 Ma 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
84-66 Ma, Campanian to Maastrichtian Allen Formation, Argentina Known to be the first unambiguous azhdarchid from South America.
  1. Arambourgiania philadelphiae
70.6-66 Ma Jordan
  1. Eurazhdarcho langendorfensis
70-66 Ma 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
  1. Eremiasaurus heterodontus
Morocco
  1. Globidens alabamaensis
  2. Globidens dakotensis
  3. Globidens phosphaticus
  4. Globidens schurmanni
  5. Globidens timorensis
84.9-70.6 Ma, Santonian to Maastrichtian USA, East Timor A mosasaurine mosasaur with teeth vastly different from other mosasaurs, as they were globular, as suggested in its generic name. While many other mosasaurs were capable of crushing the shells of ammonites, none were as specialized in dealing with armored prey like Globidens. Globidens, unlike most other mosasaurs, had semispherical teeth with rounded nubbin-like points, which were much better suited for crushing tough armored prey like smaller reptiles and mollusks.
  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 mosasaur is small compared to most other mosasaurs.
  1. Igdamanosaurus aegyptiacus
  1. Kelyophis hechti
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar
  1. Liodon anceps
  2. Liodon compressidens
  3. Liodon mosasauroides
  4. Liodon sectorius
99.7-66 Ma, Cenomanian to Maastrichtian
  1. Madtsoia madagascariensis
  2. Madtsoia pisdurensis
Campanian to Maastrichtian Madagascar

India

  1. Menarana nosymena
70-66 Ma Maevarano Formation, Mahajanga Province, Madagascar A madtsoiid that was probably fossorial, borrowing with its head.
  1. Moanasaurus mangahouangae
North Island, New Zealand A mosasaurine mosasaur 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 mosasaur that was probably a faster swimmer than most other mosasaurs.
  1. Prognathodon currii
  2. Prognathodon giganteus
  3. Prognathodon kianda
  4. Prognathodon overtoni
  5. Prognathodon rapax
  6. Prognathodon saturator
  7. Prognathodon solvayi
  8. Prognathodon waiparaensis
84.9-66 Ma, Santonian to Maastrichtian A mosasaurine mosasaur that had protective bony rings surrounding its eye sockets, indicating it lived in deep water. Its teeth are similar to those of some Triassic placodonts, so it may have lived a similar lifestyle, feeding on shellfish, large fish and sea turtles.
  1. Sanajeh indicus
68 Ma Lameta Formation, India A madtsoiid snake that is known to eat the eggs and hatchlings of dinosaurs.
  1. Socognathus unicuspis
Campanian to Maastrichtian Lance Formation, Wyoming, USA

Alberta, Canada

  1. Taniwhasaurus antarcticus
  2. Taniwhasaurus mikasaensis
  3. Taniwhasaurus oweni
85.8-66.043 Ma, Santonian to Maastrichtian Santa Marta Formation, James Ross Island, Antarctica

Conway Formation, Canterbury, South Island, New Zealand

  • Japan
A tylosaurine mosasaur closely related to Tylosaurus and Hainosaurus. T. owni was the first species discovered and the two other species (T. antarcticus and T. mikasaensis) were at first assigned to two different genera: Lakumasaurus and Yezosaurus.

Turtles[edit]

Testudines of the Maastrichtian
Taxa Presence Location Description Images
USA
  • Compsemys victa
Hell Creek Formation, Montana, USA A dermatemydid that was a moderately-sized turtle up to 30 cm (12 in) long, with a carapace covered with raised, flattened tubercles, which are not seen in any other turtle. Similar to an alligator snapping turtle, with its sharply hooked beak; this relative of the Central American river turtle must have been a semiaquatic carnivore.
Jordan A sea turtle that was one of the largest sea turtles ever.
  • Gilmoremys lancensis
Hell Creek Formation, North Dakota, USA

Lance Formation, Wyoming, USA

A softshell turtle that is known from five skulls, a mandible and an incomplete postcranial skeleton. One find consists of a nearly complete carapace and an isolated hyoplastral fragment.
  • 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.

Choristoderes[edit]

Choristoderes of the Maastrichtian
Taxa Presence Location Description Images
  • Champsosaurus albertensis
  • Champsosaurus annectens
  • Champsosaurus laramiensis
  • Champsosaurus lindoei
  • Champsosaurus natator
84.9-66 Ma, Santonian to Maastirchtian Canada, USA A gharial-like champsosaurid that hunted in rivers and swamps, catching fish with its long, tooth-lined jaws. The genus survived until the Ypresian.
  • Cteniogenys antiquus
167.7-70.6 Ma, Bathonian to Maastrichtian USA, Canada A cteniogenid originally believed to be either a lizard or a frog. It lived from the Jurassic to the Cretaceous.
  • Eotomistoma multidentata
99.7-66 Ma, Cenomanian to Maastrichtian China

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