Labyrinthodont

Large and varied group of primitive Palaeozoic amphibians, with characteristic ‘arch vertebrae’ and labyrinthine (convoluted) teeth, probably descended from crossopterygian fishes. Many were large, with heavy flattened skulls, and a straddling gait. They range from the Devonian to Triassic periods, but are predominantly found in Carboniferous and Permian strata.