aetosaur

fossil reptile

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July 20, 2026

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Aetosaurs were a group of extinct, armored reptiles that lived during the late Triassic period. These chiefly herbivorous animals were archosaurs, closely related to modern crocodilians. Aetosaurs had long, narrow bodies, small heads, and flat, pig-like snouts, and ranged from 1 to 5 meters in length. They are compared to ankylosaurs and extinct armadillos due to their armored bodies. The genus Aetosaurus is a specific example of these small, extinct aetosaurs. While most pseudosuchians, a branch of archosaurs that includes aetosaurs, were carnivorous, aetosaurs were an exception due to their herbivorous diet and armor.123

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Other lineages include the aetosaurs (“eagle lizards”), a group of herbivorous quadrupedal species that lived during the Late Triassic (229 million to 200 million years ago), the ornithosuchians (“bird crocodiles”), the rauisuchids (“Rau’s crocodiles”), and several single, ungrouped taxa. There is much disagreement concerning the evolutionary position of the…
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Other lineages include the aetosaurs (“eagle lizards”), a group of herbivorous quadrupedal species that lived during the Late Triassic (229 million to 200 million years ago), the ornithosuchians (“bird crocodiles”), the rauisuchids (“Rau’s crocodiles”), and several single, ungrouped taxa. There is much disagreement concerning the evolutionary position of the…
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