Dinosaurs

Dinosauria
3+ sacral vertebraeGlenoid faces rearOpen acetabulumBall-shaped femoral head
Theropoda
pes longer than widePes digit III longest, digit I short & elevatedmanus digit IV greatly reduced & V absent5+ sacral vertebraelots of axial skeleton pneumaticityintramandibular jointfurcula
Ceratosauria
Earliest and most primitive Theropodsproximal tarsals fusedsynsacrumtwo pneumatic foramina (holes) on cervical vertebra
Coelophysoidea
Ceratosaurs with:kinked snoutpaired head crests
Neoceratosauria
Type of ceratosaursInclude Abelisauridae and Ceratosaurus
Abelisaurs
NeoceratosaursCretaceous predatorsShort, deep skulls w/ large “horns” over eyes
Tetanurae
Theropodsteeth in jaws all rostral (forward) of orbitmanus digit IV lostcranial zygapophyses on caudal vertebrae elongate
Spinosaurids
CretaceousGondwana only (South America & Africa)Huge!Probably piscivorous (fish-eating)very long skulls with crocodilian-like teethconical teeth without serrations
Ernst Stromer von Reichenbach
Discovered first Spinosaurid (was destroyed in WWII)
Spinosauridea includes
Spinosaurids and Megalosaurs
Rev William Buckland
Discovered Megalosaurus
Sir Richard Owen
Used fossils of Megalosaurus, Iguanodon, and Hylaeosaurus as the basis for defining the order Dinosauria in 1842
Avetheropoda
Derived from Tetanuraeextra fenestrae between antorbital fenestra and narescaudal vertebrae in distal half of tail lack transverse processespubic boot
Avetheropoda consists of
Carnosaurs, Coelurosauria
Coelurosauria
Avetheropods withonly first ~15 caudal vertebrae have transverse processessemilunate carpalischium < pubisbranched integumentary (skin) structures
Ornithomimids
Coelurosaur with long forelimbs”bird mimics”
Therizinosaurs
Plant-eating Theropods
Deinonychosauria
Coeluosaurian Theropodsshoulder blade horizontalglenoid faces laterallycoracoid elongate
Sauropodomorph
Saurischian dinosaurs 10 or more cervical vertebrae, usually very elongatedteeth serrated (in most groups), with denticles oriented 45° to tooth axisbone between nares flattenedLarge digit I on manus (claw)cranium small compared to body
Sauropodomorpha consists of
Prosauropoda, Sauropoda
Prosauropods
first common dinosaurian herbivoresfirst large vertebrates to exploit niche of tall plantsknown from every continent except Australialots of small teeth in long jawsfacultative bipedsSlowhave enlarged claw on thum
Sauropods
Obligate quadrapedscervicalized thoracic vertebrae (? 11+ cervicals)laminae & fossae on vertebrae cervical vertebrae opisthocoelous4+ sacral vertebraelots of caudal vertebraereduced # carpals to 3 or fewerreduced # phalanges on manus digits IV & Vfemur very long (longer than humerus + radius)nares retracted caudally
Lamina
Thin ridge or sheet of bone
Fossa
Dead-end depression or excavation on bone surface
Amphiplatyan
Vertebrae flat on both ends
Amphicoelous
Vertebrae concave both ends
Procoelous
Vertebrae concave front, convex back
Opisthocoelous
Vertebrae convex front, concave back
Titanosaurs
Peg-toothed Sauropods
Diplodocoids
Neosauropods with:extremely long necks and tailspeg-toothedextreme narial retractionvery tall spinous processes on caudal thoracic, sacral, and proximal caudal vertebrae
Flagellicaudata
Neosauropods with:distal tail composed of long, rod-like vertebrae (whip tail)spinous processes on cervical and thoracic vertebrae forked
Diplodocidae
family of Sauropods associated with Morrison FormationEdward Cope & Othniel Marsh”Great Dinosaur Rush”
Flagellicaudata consists of
Diplodocidae, Dicraeosauridae
Macronaria
Neosauropods with nares > orbit
Camarasaurus
MacronariaMost common dinosaur found in Morrison Formation
Brachiosauridae
Macronaria w/ arm > leg
Brachiosauridae + Titanosauria
Macronaria w/kinked femurvertebrae made of spongy bone
Sauropod hiatus
N. America: no sauropods between beginning & end of Late Cretaceous!
Titanosauria
Macronaria withproximal and middle caudal vertebrae strongly procoelous
Includes smallest sauropods
Titanosauria
Gastroliths
Found in Sauropod gizzardsprobably related to gut fermentation
Thyreophora
Name means “shield bearer”basal ornithischians
Thyreophora
osteoderms (called “scutes”) in rows parallel to midline on both lateral and dorsal surfaces of torsowell-developed postorbital processsquat statue – short legs compared to bodyall but the earliest forms were quadrupedal
Thyreophora consists of
Stegosauria and AnkylosauriaBoth have toothless keratinous beak
Ankylosauria
broad compressed skullarmor covering cranial structures andloss of all temporal fenestraefused sacral vertebrae, a synsacrumclosed acetabulumhorizontal iliumlots of body armor
Two families of Ankylosauria
Nodosauridae, Ankylosauridae
Nodosauridae
Ankylosaur with skull with no horns large spikes on side(small spikes or no spikes on back) no tail club
Ankylosauridae
Ankylosaur with skull with horns large spikes on back(small spikes or no spikes on sides) tail club
Stegosauria
Member of Ankylosauriaparasagittal platesA few had parascapular spines
Ornithopods
Ornithischian dinosaurs w/teeth in maxilla more dorsal (higher) than those in premaxilla (i.e tooth rows at different heights)Occlusal surface more dorsal than jaw jointPremaxilla with elongate processCrescent-shaped paroccipital process
Hypsilophodontida
Type of Ornithopodssmall-medium sizedBipedalNorth America & Eurasiaoriginally thought to be monophyletic; is now known to be paraphyletic
Pleurokinesis
ability of maxilla to swing laterally (outward) when mouth is closing
First Ornithischians to evolve Pleurokinesis, opposable pinky
Hypsilophodontidae
Leaellynasaura
Small hypsilophodontid with enormous eyes
Iguanodontia
Ornithopods w/ a beakpremaxilla expanded and toothlessFacultative bipeds
Dr. Gideon Mantell
Discovered teeth of Iguanodon
Iguanodontoidea
Ornithopod w/diastema between beak and maxillary teethnarrowed handshoof-like pedal unguals
Hadrosauridae
“duck-billed” ornithopodsFacultative bipedswell-developed dental batteriesloss of antorbital fenestra8 sacral vertebraeloss of digit I on manusarms elongate (~ legs)
Hadrosaurine
Crestless and solid-crested hadrosaurs
Lambeosaurine
Hollow-crested hadrosaur
Marginocephalia
Shelf of bone extending back over occipital portion of skullShortened pubisWidely-spaced acetabula (hip sockets)
Pachycephalosauria
“Bonehead” group of Marginocephalia
Homocephalidae
PachycephalosaursGenerally smallFlat, very bony heads
Pachycephalosauridae
Pachycephalosaur w/Domed headsExtremely thick, boney skull
Ceratopsia
Marginocephalids w/keratinous beakfrill formed by parietalstriangular shaped skull(when viewed dorsally)”vaulted” or high palate
Two groups of Ceratopsia
Psittacosauridae, Neoceratopsia
Psittacosauridae
Member of CeratopsiaParrot-like, toothless beak
Neoceratopsia consists of
Proceratopsidae, Ceratopsidae
Aves
Theropods w/ arms > legs anisodactyly streptostylic quadrate
Evidence of Bolide Impact
cratershocked mineralstektitesimpact-induced sedimentary depositsenrichment of rare elements