Dinosaur taxonomy, Wikipedia

Dinosauria

Saurischia ("lizard-hipped"; includes Theropoda and Sauropodomorpha)

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Theropoda (all bipedal; most were carnivorous)

 Herrerasauria (early bipedal carnivores)

 Coelophysoidea (small, early theropods; includes Coelophysis and close relatives)

 Dilophosauridae (early crested and carnivorous theropods)

 Ceratosauria (generally elaborately horned, the dominant southern carnivores of the Cretaceous)

 Tetanurae ("stiff tails"; includes most theropods)

 Megalosauroidea (early group of large carnivores including the semi-aquatic spinosaurids)

 Carnosauria (Allosaurus and close relatives, like Carcharodontosaurus)

 Coelurosauria (feathered theropods, with a range of body sizes and niches)

 Compsognathidae (common early coelurosaurs with reduced forelimbs)

 Tyrannosauridae (Tyrannosaurus and close relatives; had reduced forelimbs)

 Ornithomimosauria ("ostrich-mimics"; mostly toothless; carnivores to possible herbivores)

 Alvarezsauroidea (small insectivores with reduced forelimbs each bearing one enlarged claw)

 Maniraptora ("hand snatchers"; had long, slender arms and fingers)

 Therizinosauria (bipedal herbivores with large hand claws and small heads)

 Oviraptorosauria (mostly toothless; their diet and lifestyle are uncertain)

 Archaeopterygidae (small, winged theropods or primitive birds)

 Deinonychosauria (small- to medium-sized; bird-like, with a distinctive toe claw)

 Avialae (modern birds and extinct relatives)

 Scansoriopterygidae (small primitive avialans with long third fingers)

 Omnivoropterygidae (large, early short-tailed avialans)

 Confuciusornithidae (small toothless avialans)

 Enantiornithes (primitive tree-dwelling, flying avialans)

 Euornithes (advanced flying birds)

 Yanornithiformes (toothed Cretaceous Chinese birds)

 Hesperornithes (specialized aquatic diving birds)

 Aves (modern, beaked birds and their extinct relatives)

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Sauropodomorpha (herbivores with small heads, long necks, long tails)

 Guaibasauridae (small, primitive, omnivorous sauropodomorphs)

 Plateosauridae (primitive, strictly bipedal "prosauropods")

 Riojasauridae (small, primitive sauropodomorphs)

 Massospondylidae (small, primitive sauropodomorphs)

 Sauropoda (very large and heavy, usually over 15 meters (49 feet) long; quadrupedal)

 Vulcanodontidae (primitive sauropods with pillar-like limbs)

 Eusauropoda ("true sauropods")

 Cetiosauridae ("whale reptiles")

 Turiasauria (European group of Jurassic and Cretaceous sauropods)

 Neosauropoda ("new sauropods")

 Diplodocoidea (skulls and tails elongated; teeth typically narrow and pencil-like)

 Macronaria (boxy skulls; spoon- or pencil-shaped teeth)

 Brachiosauridae (long-necked, long-armed macronarians)

 Titanosauria (diverse; stocky, with wide hips; most common in the Late Cretaceous of southern continents)

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Ornithischia ("bird-hipped"; diverse bipedal and quadrupedal herbivores)

 Heterodontosauridae (small basal ornithopod herbivores/omnivores with prominent canine-like teeth)

 Thyreophora (armored dinosaurs; mostly quadrupeds)

 Ankylosauria (scutes as primary armor; some had club-like tails)

 Stegosauria (spikes and plates as primary armor)

 Neornithischia ("new ornithischians")

 Ornithopoda (various sizes; bipeds and quadrupeds; evolved a method of chewing using skull flexibility and numerous teeth)

 Marginocephalia (characterized by a cranial growth)

 Pachycephalosauria (bipeds with domed or knobby growth on skulls)

 Ceratopsia (quadrupeds with frills; many also had horns)

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