Dinosoor - Classification - Taxonomy

Taxonomy

The following is a simplified classification of dinosaur groups based on their evolutionary relationships, and organized based on the list of Mesozoic dinosaur species provided by Holtz (2008). A more detailed version can be found at Dinosaur classification. The cross (†) is used to signify groups with no living members.

• Dinosauria

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

• 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)

• †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)

• †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)