Formerly a suborder of Stegocephalia

• Amphibia having vertebrae whose component elements are fused into a single piece

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The Stereospondyli are a group of extinct temnospondyl amphibians . Relative to other early tetrapods ( labyrinthodonts ), they had simplified backbones, where the whole vertebra was made of a single intercentrum , topped by a neural arch . The whole vertebral ...