noun
- Any of an extinct group of early reptiles from the Carboniferous and Permian periods, characterized by a cup-shaped socket in the vertebra.
Usage: paleontology; technical
Examples
- Cotylosaurs are considered the ancestors of modern reptiles, amphibians, and mammals.
- The cotylosaur skeleton revealed features intermediate between amphibians and true reptiles.
- Paleontologists study cotylosaur fossils to understand the evolution of early amniotes.
- The name cotylosaur comes from the cup-shaped vertebral socket characteristic of these creatures.