arenasid
Arenasids are a group of extinct marine reptiles that lived during the Mesozoic era, primarily in the Late Triassic and Early Jurassic periods. They are characterized by their distinctive, armored bodies and are believed to have been semi-aquatic or fully aquatic. Arenasids are known for their unique body structure, which includes a series of bony plates or scutes that covered their bodies, providing protection and possibly aiding in buoyancy.
The most well-known genus of arenasids is Arenysaurus, which was discovered in Spain. Other genera include Arenysaurus,
Arenasids are significant in the study of marine reptile evolution, as they represent an early stage in