Paleo 419 Final

Who discovered Chasmosaurus (Ceratopsidae)

Russel

Ceratopsidae Stance

Slightly sprawling based on footprints but not as much as the proposed “Russell Sprawl”

Chasmosaurinae Synapomorphies

• long squamosals and squamosal-parietal frill

• enlarged rostral with deeply concave posterior margin

• interpremaxillary fossa

• keyhole shaped frontal fontanelle

• triangular SQ epoccipitals

Purpose of the keyhole shaped frontal fontanelle in Chasmosaurinae

Adds strength because supraorbital horns are long and heavy

What group is Regaliceratops peterhewsi in?

Chasmosaurinae

Chasmosaurus belli (Chasmosaurinae)

• found at edge of hill with its arms lost in a sinkhole

• Dinosaur Park Formation

• Upper Cretaceous

Eotriceratops xerinsularis (Chasmosaurinae)

• Dry Island Park, Alberta

• Horseshoe Canyon Formation

• Triceratops ancestor

• Destroyed by acidic water

Centrosaurinae Synapomorphies

• PM extends below alveolar margin

• postorbital horns less than 15% length of skull

• jugal intratemporal flange

• short squamosal and squamosal-parietal frill

• 6-8 parietal epoccipitals on each side

• parietal epoccipital 2 medially directed

• parietal epoccipital 3 can become a large horn

• Frills too thin for self defence

Monoclonius (Centrosaurinae)

• first described by E.D. Cope

• Montana

What group is Centrosaurus apertus, Centrosaurus nasicornis, Xenoceratops foremostensis, Albertaceratops nesmoi, Coronosaurus brinkmani in?

Centrosaurinae

• Centrosaurus nasicornis - DPP

• Xenoceratops foremostensis - distinctive frills

• Albertaceratops nesmoi - type from AB

Styracosaurus albertensis (Centrosaurinae)

• Tyrell museum

• Scott Pearsons found weathered horn with a skull underneath

• Had bosses as well

Pachyrhinosaurus (Centrosaurinae)

• Wann Langston collected at Scabby Butte

• Bonebed from Pipestone Creek with 300 bones per cubic meter

• Abbasid’s look like Triceratops

• Boss instead of horns

• Wapiti river

Achelosaurus (Centrosaurinae)

New Pachyrhinosaurus species

• Campanian - Upper Cretaceous

• DPP

Pachyrhinosaurus from Alaska (Centrosaurinae)

Pachyrhinosaurus peretorum

• Maastrichtian

Hovasaurus + Centrosauru death assemblages

Hovasaurus young and old specimens found suggesting natural deaths. Centrosaurus deaths mostly found in one age suggesting catastrophic death

Scelidosaurus (Thyreophora)

• Lower Jurassi

• England

• named in 1860 by Owen

• Marine deposits

• Predentary lost

• Cingulum

• Teeth with cylindrical, tall roots

Stegosaurs (Thyreophora)

• low tubular skulls

• flattened dorsal surface of p

• Originally thought to have 2 brains

Huyangasaurus taibaii (Thyreophora)

• late Jurassic

• China

• sister group to Stegosauridae

• retains, premaxillary teeth, and ossified tendons in tail

• Double series of plates on back

• preacetabular process 35 degrees outward

• Ilia diverged at the front

• Broad abdomen

• Only 1st digit is a hoof

• Plates with blood vessel canals to help cool down

Tuojiangosaurus multispinus (Thyreophora)

• late Jurassic

• China

• Different plates to Stegoceras

Stegoceras (Thyreophora) similarities to Sauropods

pedal digit I lost III and IV with 3 phalanges verts with small neural canal & tall neural arch

Liaoningosaurus paradoxus (Thyreophora)

• Primitive Ankylosaur

• Size of a fist

• Aquatic deposits

• Fish gut contents

Nodosauridae (Thyreophora)

• supraorbital boss rounded

• only bocc in occipital condyle

• ornamentation on pm

• Heavily ornamented premaxillary

Sauropelta edwardsi (Nodosauridae)

• Complete set of scutes found

• Early Cretaceous, Montana

Edmontonia and Panoplosaurus (Nodosauridae)

• Same species

• No tail club

• Shoulder spikes

• Footprints found

• Teeth way smaller than ankylosaur

• Cingulum

Borealopelta markmitchelli (Nodosauridae)

• Brown, Henderson, Vinther, Sistiaga, Herrera, Summons

• Soft tissue found

• Stomach contents

• Had countershading

• Antarctica

• Vertebrae with fused tendons

Ankylosauridae (Nodosauridae)

• Late Cretaceous, North America

• pyramidal sq boss

• tail club

• Tail club bigger than skull

• Advanced lineage

• Osteoderms fused to dermal bones

• Scutes cover external mandibular fenestrae

• Antorbital fenestrae closed

• Skate covers eye like a eyelid

• Ilia spread to make room for plant fermentation vat

What group is Struthiosaurus and Euocephalus in?

Ankylosauridae (Nodosauridae)

Pinacosaurus quarry

• Bayan Mandahu

• China

• Suggest gregarious ankylosaurs

• Babies found

Alag Teg formation

• Mongolia

• Baby anklosaurs found but no adults

• Lots of limbs

What group is Pinacosaurus, Tsagantegia, Saichania, Tarchia and Zaraapelta nomadis in?

Advanced Ankylosauridae (Nodosauridae)

Sauropodomorpha synapomorphies

• transversely compressed internarial bar

• diameter of external naris at least 60% orbit diameter

• infratemporal fenestra extends forward to point below orbit

• tooth crowns overlap in lateral view

• ventral deflection of anterior end of dentary

Prosauropoda (Sauropodomorpha)

• late Triassic

• Europe, Greenland, Sauriermuseum Frick

• Posteriorly inset first dentary tooth

• Large pubic obturator foramen

Anchisaurus (Sauropodomorpha)

• McCoy Brook Fm.

• Lower Jurassic of Nova Scotia

Lufengosaurus (Sauropodomorpha)

• Lower Jurassic of Lufeng Basin

• Yunnan, China

• 30+ skeletons found

Massospondylus (Sauropodomorpha)

• early Jurassic

• South Africa

• Argentina, Arizona

• Embryos found

Mussaurus (Sauropodomorpha)

• tiny

• Late Triassic

• Argentina

Sauropoda (Sauropodomorpha) synapomorphies

• pneumatic vertebrae in neck and trunk

• External sculpturing by pneumatic tissue

• Massive columnar limbs

• Short lower legs, hands, feet

• Pneumatic entrance in the centrum

• I-beam shaped bones - strength, least weight

Shunosaurus (Sauropoda)

• Late Jurassic, China

• snout broadly rounded in dorsal view

• posterior margin of external naris is posterior to posterior margin of antorbital fenestra

What group is Mamenchisaurus and Omeisaurus in

Sauropoda (Sauropodomorpha)

Nigersaurus (Sauropoda)

• Early Cretaceous, Niger

• part of Rebacchisauridae

• Primitive skulls

Dicraeosaurus (Diplodocoidea, Sauropoda)

• Late Jurassic, Tanzania

• Tall neural spines, bifurcated

• Posterodorsally placed external nares

Amargasaurus and Pilmatueia faundezi (Sauropoda)

• tall spines on neck

• Argentina

Diplodocus longus (Sauropoda)

• Elongated dentary, tiny mouth

• Late Jurassic

• Tall neural spines

• Long neck and tail

Barosaurus lentus (Sauropoda)

Thought to have stood on hind legs to get leaves like elephants

Supersaurus (Sauropoda)

• very long neck

• Late Jurassic

• Dry Mesa, Colorado

Macronaria groups (Sauropoda)

Includes camarasaurids, brachiosaurids, titanosaurids

Brachiosauridae (Macronaria, Sauropoda) synapomorphy

• enlarged deltopectoral crest

• H/F length ratio of almost 1.0

Brachiosauridae (Macronaria, Sauropoda) species

• Brachiosaurus - Late Jurassic USA

• Giraffatitan - Tanzania

• Europasaurus - Late Jurassic Germany

Kent Stevens

showed that the osteological neutral pose in Berlin Brachiosaurus specimens put the head just over 6 m above the ground

Titanosauria (Macronaria, Sauropoda) synapomorphy and species

• robust radius and ulna (proximal width of radius at least a third of its length)

• Alamosaurus, Argentinosaurus, Saltasaurus

Argentinosaurus (Titanosauria, Macronaria, Sauropoda)

• largest dinosaur ever found

• Plaza Huincul, Argentina

Los Barrealis

Neuquen, Argentina, bone bed at the end of a lake

Fuglognkosaurus (Titanosauria, Macronaria, Sauropoda)

• Portezuelo Formation

• Cretaceous, Argentina

Auca Mahuida

• bone bed

• Has lots of sauropod eggshells

• Skin impressions on eggshells

• Embryo skull found

Opisthocoelicaudia and Nemegtosaurus (Titanosauria, Macronaria, Sauropoda)

• Mongolia

• Large femur found

• Footprints found

Theropoda synapomorphies

• reduced number of fingers

• Pneumatic skull

• most diverse (successful) clade of dinosaurs

• Late Triassic (Carnian) to Recent, and on all continents

What group is Eoraptor and Herrerasauridae in

basal saurischians outside of Theropoda

Tawa

• Part of Neotheropoda

• Ghost ranch

• Very basal

Ceratosauria (Neotheropoda) synapomorphies

• Shares characteristics as Coelophsis

• axial neural spine extends anteriorly beyond prezygapophysis

• dorsoventrally low postaxial neural spines

• transverse processes on dorsals triangular and backswept

• supracetabular crest overhangs most of front of acetabulum

• pubis bows anteriorly

• astragalocalcaneum

• 4th finger remanent

Coelophysoidea (Neotheropoda)

• PM-Max articulation

• subnarial diastema

• premax teeth do not extend beneath external naris

• maxillary alveolar margin curves sharply anteriorly

• Chinle Formation

• Ghost Ranch, New Mexico

• Upper Triassic

• Bone assemblage found shows pack behaviour and drought death

What bone forms the crest in Dilophosaurus? (Ceratosauria, Neotheropoda)

Formed by nasal + lacrimal

Dilophosaurus and Sinosaurus (Ceratosauria, Neotheropoda)

• early Jurassic

• Premaxilla/maxilla separation

• Sinosaurus had pits on the side of its face - poison gland?

Neoceratosauria (Neotheropoda) synapomorphies

• derived Ceratosauria

• 6 sacral vertebrae

• narrow, reduced mid-sacral centra

• cnemial crest anteroposteriorly long

• Brevis canal wider than theropoda

Quilmesaurus curriei (Neoceratosauria, Neotherpoda)

• Late Cretaceous

• Argentina

• Large cnemial crest

• Named after prof

Carnotaurus (Neoceratosauria, Neotheropoda)

• Argentina

• Skin impressions

• Medium sized

• Small teeth

• Broad nasal

• Short skull

How long did Neoceratosauria (Neotheropoda) survive?

survive until end of Cretaceous in southern hemisphere

• before Cretaceous was the dominant carnivores

Aucasaurus (Neoceratosauria, Neotheropoda)

• late Cretaceous

• Argentina

• Very tiny arms - has tibiotarsus

• Big ball joint links to scapula coracoid

• 4 fingers

Majungatholus, Masiakasaurus and Noasaurus (Neoceratosauria, Neotheropoda)

• late Cretaceous

• Argentina

• Tiny phalanx preserved

Cryolophosaurus synapomorphies (Neoceratosauria, Neotheropoda)

• Antarctica

• Big lacrimal crest

• Squamosal contacts jugal to derived temporal fenestra (like advanced allosaurs)

• Primitive ankle

Tetanurans traits

• sharp rim defining antorbital fossa

• prominent scapular acromian

• fibular condyle of proximal head of Tibia distinctly inset from cnemial crest

Allosaurus (Tetanurans) traits

• MC II 180% > MC I

• shaft width of MC III < 50% shaft width of MC II

• triangular proximal end of MC III on palmar surface of base of MC II

• Knob on the femur

Groups in Carnosauria (Tetanurans)

Allosaurids, Carcharodontosaurids, Megaraptorids, Monolophosaurus, Neovenatorids, Sinraptorids

Carnosauria traits (Tetanurans)

• long axis of naris more than half length of long axis of orbit

• lateral surface of nasal participates in edge of antorbital fossa + pneumatic nasal recesses

• paroccipital processes directed posterolaterally from occiput so distal ends below level of foramen magnum

Important localities to Carnosauria (Tetanurans)

Jiangjunmiao and Wucaiwan ‘color rock’ formations in China

Monolophosaurus jiangi (Carnosauria, Tetanurans)

• Xinjiang

• China Middle Jurassic

• Skull like Creatosaurus

• Post cranial like allosaurides

• Crest

Spinosauroidea (Tetanurans)

• includes first dinosaur found - megalosaur

• Late Cretaceous

• Skull like crocs

• Non serrate teeth

• Northern Africa

Spinosaurus (Spinosauroidea, Tetanurans) traits

• Late Cretaceous

• Northern Africa

• PM ant to external naris longer

• anterior ramus maxilla longer than high

• Elongate premaxilla with diastema

• Thin swimming tail

• Long neural spines

• Legs like allosaurs

Baryonyx walkeri and Irritator challengeri (Spinosauroidea subfamily, Tetanurans)

• distinctive braincase

• Serrated theropod teeth

• Long legs

• Africa

Asfaltovenator vialidadi

• Chubut

• Argentina Lower Jurassic

• Spinosauroidea, Tetanurans

Sinraptor dongi (Spinosauroidea, Tetanurans)

• Late Jurassic

• Northwestern China

• Very open skull

• extra openings in antorbital fossa

• 4 premaxillary teeth instead of 5

Fukuiraptor kitadani (Spinosauroidea, Tetanurans)

• Fukui Prefectural Museum, Japan

• Currie

• Early Cretaceous

• astragalus found in Japan and Australia

• Katsuyama Quarry - Fukui Prefecture with many individuals found with altricial death

Megaraptor namunhuiquii (Spinosauroidea, Tetanurans)

• huge claws

• Originally thought to be a dromeosaur

• Skull found in a wall of a canyon

• ilium like tyrannosaur with penumatosars or pneumatic vertebrae through sacral ribs

• First dinosaur ever found by Owen

Neovenator salerii (Megaraptoridae, Tetanurans)

• Early Cretaceous

• Isle of Wight

Cleveland-Lloyd Quarry

• Utah Late Jurassic

• Has huge bonebed

• Quicksand killed lots of prey which attracts predators to die

• Allosaurus (Megaraptoridae, Tetanurans)

Acrocanthosaurus (Megaraptoridae, Tetanurans)

• found during WWI

• North Carolina

• Very big, similar to tyrannosaurus

• 5 premaxillary teeth like allosaurs

• Lower Cretaceous

Carcharodontosaurus vs Tyrannosaurus teeth (Megaraptoridae, Tetanurans)

• Tyrannosaurus teeth were better for breaking bones

• Carcharodontosaurus teeth were better for shearing with serrations and flatter

Giganotosaurus (Megaraptoridae, Tetanurans)

• longer skull than Tyrannosaurus

• Slicing teeth

• Northern Patagonia

• Argentina

• Huge

Mapusaurus roseae (Megaraptoridae, Tetanurans)

• 10 individuals found together

• Bigger than gigantosaurus

Where was a holotype of Tyrannosaurus rex found (Coelurosaurs)

Quarry of in Dawson County, Montana

• Barnum Brown

Tyrannosauroidea (Coelurosaurs)

• U. Jurassic (Asia) to U. Cretaceous, N. Hemisphere

• D-shaped PM teeth

• fused nasals

• large posterior surangular foramen

• median vertical ridge on lateral surface of ilium

• elongate metatarsals (arctometatarsalian)

Dilong paradoxis (Tyrannosauroidea, Coelurosaurs)

• feathered tyrannosaur - insulation

Gorgosaurus libratus (Tyrannosauroidea, Coelurosaurs)

• 2/3rds grown

• No feathers

• Skin impression

• Lawrence Lambe

What group is Daspletosaurus, Gorgosaurus, Albertosaurus sarcophagus in?

Tyrannosauroidea, Coelurosaurs

• in the same paper as T-Rex

Important Tyrannosauroidea (Coelurosaurs) limb bone bed

Dry Island Buffalo Jump Provincial Park

• found by Barnum Brown

• Can see age differences, Tyrannosaurs have a huge growth spurt in their teens

Alioramus remotus (Tyrannosauroidea, Coelurosaurs)

• Natural History Museum of Mongolia

• Smaller

• Lower skull

• Less bite force

Tyrannosaurus Rex (Tyrannosauroidea, Coelurosaurs)

• huge bite force

• Ears face forward 50% bigger brain

• Good smell and hearing

• Teens hunt because they are more agile

• Live in packs

Medullary bone

• Seen in Tyrannosauroidea (Coelurosaurs) and modern birds

• Builds eggshells

• Only in females that are ready to lay eggs

• Spongy bone inside femur

• Helps to not lose calcium from bones

Compsognathidae (Coelurosaurs)

• Scipionyx, Compsognathus, Sinosauropteryx

• fan-shaped dorsal spines

• more than 60 caudal vertebrae

• digit I longest in hand

• manual ungual of digit I more than 2/3 length of radius

Sinosauropteryx (Compsognathidae, Coelurosaurs)

• found in bone bed with Compsognathus

• China split fossil in half to make more money

• First feathered theropod

• Arms short, long claws

Ornithomimus (Compsognathidae, Coelurosaurs)

• late Cretaceous

• Alberta

• “Bird mimic”

• Phalanges missing due to a river

• Keratinous beak

• Feather tracks on arm

• melanosomes found