Archaeothyris
Oldest undisputed synapsid, known from Late Carboniferous Nova Scotia.
Archaeothyris is an extinct genus of ophiacodontid synapsid from the Late Carboniferous of Nova Scotia, dated to 306 million years ago. Along with the less completely known Echinerpeton, it represents the oldest undisputed synapsid. Its name, meaning ancient window, refers to the temporal fenestra in the skull that marks it as an early synapsid.
Quick Facts
- Type species
- Archaeothyris florensis
Facts from the source article.
Did You Know?
- Archaeothyris had strong jaws that could open wider than those of early reptiles.
- It possessed a pair of enlarged canines, though its other sharp teeth were uniform in size and shape.
- The first toe of Archaeothyris is smaller than the second.
Discovery and paleoecology
Fossils of Archaeothyris were first described in 1972 from the Joggins Fossil Cliffs, the same site that yielded the early reptiles Hylonomus and Petrolacosaurus. It lived about 306 million years ago in a coal forest dominated by giant club mosses such as Lepidodendron, which reached 50 m in height. Archaeothyris and other early amniotes inhabited the moist forest floor alongside terrestrially adapted labyrinthodont amphibians.
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