TETRAPODA
CLASSIFICATION
Animalia: Vertebrata
CLADOGRAM:
—Tetrapoda “four feet”
|–Elginerpetonidae *
`–+–+?-Metaxygnathus *
| `–Ventistega *
`–+–Acanthostega *
`–+–Ichthyostega *
`–+?-Antlerpeton *
|–Hynerpeton *
`–+–Tulerpeton *
`–+–Crassigyrinus *
`–+–Temnospondyli *
`–+–Whatcheeria *
`–+–Embolomeri *
`–+–Gephyrostegida *
`–+?-Solenodonsaurus *
|?-Chroniosuchidae *
|?-Limnoscelidae *
|–Seymouriamorpha *
|?-Nycteroleteridae *
|?-Tokosauridae *
|?-Tseajaiidae *
`–+ =Tetrapoda sensu stricto
|–Amphibia “double lives” (frogs, salamanders, blindworms, etc.)
`–Amniotomorpha “Amniota forms”
|?-Lysorophia *
`–+–Westlothiana *
`–“Amniotiformes” “Amniota forms”
|–Diadectomorpha *
`–Amniota (possess amniotic sac in egg)
|?-Acleistorhinidae *
|—->Synapsida
`—->Sauropsida
ESSAY
Among terrestrial vertebrates, dinosaurs belong to Amniota, a clade characterized by the ability to procreate on land. Of the two main branches of amniotes, dinosaurs belong to Sauropsida, which includes other reptiles as well. The sister clade to Sauropsida, Synapsida, includes mammals. |
IMAGES
Triadobatrachus massinoti, a Triassic amphibian closely related to frog |