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Cladogram of the Ornithischians

Master Ornithischian Cladogram


TAXA, CHARACTERS, FORMATIONS AND LOCATIONS

(most important genera in red)


I. Ornithischia

1. Dinosauria: open acetabulum
2. Ornithischia: process of pelvis points backward
3. Saurischia: metacarpal of digit I robust and twisted
4. Genasauria: cheeks
5. ?no shared derived characters

Lesothosaurus, Early Jurassic, Stormberg Group, South Africa
6. Thyreophora: armor
7. Cerapoda: uneven enamel on teeth
8. ?no shared derived characters
Scelidosaurus, Early Jurassic, Lias, England
Scutellosaurus, Early Jurassic, Glen Canyon Group, Arizona, USA
9. Stegosauria: armor as plates or spines on back
10. Ankylosauria: armor or small plates over back
11. Ankylosauridae: club on tail
Ankylosaurus, Late Cretaceous, Judith River beds, Alberta, Canada
Pinacosaurus, Late Cretaceous, Mongolia
Euplocephalus, Late Cretaceous, Judith River beds, Alberta, Canada
12. Nodosauridae: complex palate and large armor plate on top of center of skull
Nodosaurus, Early Cretaceous, Cloverly Formation, Montana
Edmontonia, Late Cretaceous, Judith River beds, Alberta, Canada
13. Kentrosauridae: armor as spines on most of back
Kentrosaurus, Late Jurassic, Tendaguru Formation, Tanzania
14. Stegosauridae: armor as plates on back
Stegosaurus, Late Jurassic, Morrison Formation, western USA
15. Marginocephalia: bony shelf on back of head
16. Pachycephalosauria: dome-like thickening on skull
Prenalocephale, Late Cretaceous, Mongolia
Pachycephalosaurus, Late Cretaceous, Judith River beds, Alberta, Canada
17. Ceratopsia: rostral bone on snout
18. Psittacosauridae: reduction in manus
Psittacosaurus, Early Cretaceous, Mongolia
19. Neoceratopsia: long frill
Protoceratops, Late Cretaceous, Mongolia
Triceratops, Late Cretaceous, Hell Creek beds, Western USA
20. Ornithopoda: jaw joint below tooth rows
21. elongate hands with large claws
Heterodontosaurus, Early Jurassic, Stormberg Group, South Africa
22. no name (Hypsilophodontidae + Iguanodontidae + Hadrosauridae): prepubic process well developed
23. Hypsilophodontidae: strong ridge on side of teeth
Hypsilophodon, Early Cretaceous, England
24. no name (Iguanodontidae + Hadrosauridae): reduction in digit I of hand
25. Iguanodontidae: spike-like digit I on hand
Iguanodon, Early Cretaceous, Wealden beds, England and Belgium
Camptosaurus, Late Jurassic, Morrison Formation, western USA
Ouranosaurus, Early Cretaceous, Niger
26. Hadrosauria: loss of digit 1 and duck-like snout
Hadrosaurus, Late Cretaceous, New Jersey, USA
Saurolophus, Late Cretaceous, Mongolia
Anatotitan, Late Cretaceous, Hell Creek beds, Montana, USA
Maiasaura, Late Cretaceous, Two Medicine Formation, Montana, USA
Parasaurolophus, Late Cretaceous, Judith River beds, Alberta, Canada
Corythosaurus, Late Cretaceous, Judith River beds, Alberta, Canada

Cladogram of the Saurischians

Master Saurischian Cladogram


TAXA, CHARACTERS, FORMATIONS AND LOCATIONS

(most important genera in red)


II. Saurischia

1. Dinosauria: open acetabulum
2. Saurischia: metacarpal of digit I robust and twisted
3. Ornithischia: process of pelvis points backward
4. ? no shared derived characters

Herrerasaurus, Ischigualasto Formation, Argentina
5. Sauropodomorpha: small head and long neck
6. Sauropoda: dorsal vertebrae converted to cervicals, elongating neck
7. Prosauropoda: apron-shaped pubis
Plateosaurus, Late Triassic, Keuper, Germany
8. Brachiosauridae: forelimbs as long as, or longer than, hind limbs
Brachiosaurus, Late Jurassic, Morrison Formation, Western USA; Tendaguru Formation, Tanzania
Ultrasaurus, Late Jurassic, Morrison Formation, Western USA
Camarasaurus, Late Jurassic, Morrison Formation, Western USA
9. Diplodocidae: teeth restricted to front of mouth
Diplodocus, Late Jurassic, Morrison Formation, Western USA
Seismosaurus, Late Jurassic, Morrison Formation, Western USA
Apatosaurus, Late Jurassic, Morrison Formation, Western USA
Dicraeosaurus, Late Jurassic, Tendaguru, Tanzania
Barosaurus, Late Jurassic, Morrison Formation, Western USA
10. Titanosauridae: Armor
Saltosaurus, Cretaceous, Argentina
Amagarosaurus, Cretaceous, Argentina
11. Theropoda: furcula, 1st toe does not contact the ankle

CLADOGRAM OF THE THEROPODA

THEROPOD CLADOGRAM

1. Theropoda – furcula, 1st toe does not contact the ankle
2. Promaxillary fenestra present in maxilla*
3. Tetanuran - loss of 4th finger
4. Coelurosauria - long grasping arms
5. Orbit round in lateral view
6. Semilunate carpal
7. Tail with distinct flexion point*
8. Parietals fused*
9. Maniraptora - true feathers
10. Rounded premaxillary symphysis*
11. Shoulder with scapula and coracoid L-shaped*
12. Deinonychosauria - modified 2nd toe as "killing claw"
13. Troodontidae- small closely spaced teeth
Troodon, Late Cretaceous, Judith River beds, Alberta, Canada
14. Coelophysoidea – downturned premaxilla
Coelophysis, Late Triassic, Chinle Group, Late Cretaceous, W. North America
Dilophosaurus, Early Jurassic, Glen Canyon Group, Late Cretaceous, W. North America
15. Neoceratosauria - 6 vertebrae in the sacrum
Ceratosaurus, Late Jurassic, Morrison Formation, Western USA
Carnotarus, Cretaceous, Argentina
Giganotosaurus, Cretaceous, Argentina
16. Carnosauria – elongate nasals (many times bearing a crest)
Allosaurus, Late Jurassic, Morrison Formation, Western USA
17. Tyrannosauridae - fused nasals
Dilong, Early Cretaceous, Yixian Formation, China
Tyrannosaurus, Late Cretaceous, Hell Creek Formation, Western, USA
18. Ornithomimosauria - elongated hands, each finger is subequal
Gallimimus, Late Cretaceous, Mongolia
Deinocheirus, Late Cretaceous, Mongolia
19. No significant unique derived characters
Ornitholestes, Late Jurassic, Morrison Formation, Western USA
20. Compsognathidae - more than 60 caudal vertebrae
Compsognathus, Late Jurassic, Solenhofen Limestone, Germany
Sinosauropteryx, Early Cretaceous, Liaoning lake beds, China
21. Alvarezsauridae - highly reduced forelimbs
Mononykus, Late Cretaceous, Mongolia
22. Therizinosauroidea - enormous claws
Therizinosaurus, Late Cretaceous, Mongolia
Segnosaurus, Late Cretaceous, Mongolia
23. Oviraptorosauria - Loss of teeth
Oviraptor, Late Cretaceous, Mongolia
Caudipteryx, Early Cretaceous, Yixian Formation, China
24. Avialae - asymmetrical feathers, metatarsals are fused at the ankle
Archaeopteryx, Late Jurassic, Sohlnofen Limestone, Germany
25. Dromaeosauridae - T-shaped frontals
Dromeosaurus, Late Cretaceous, Judith River beds, Alberta, Canada
Deinonychus,
Early Cretacoeus, Cloverly Formation
Velociraptor, Late Cretaceous, Mongolia



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