text:  Temnospondyls first appeared in the Early Carboniferous around 330 million years ago ( Mya ) . During the Carboniferous , temnospondyls included basal medium @-@ sized forms such as Dendrerpeton or large semiaquatic forms such as Cochleosaurus . Other , more derived temnospondyls , such as the amphibamids , were smaller and more terrestrial . They resembled salamanders , and some taxa , such as the genus Branchiosaurus , even retained external gills like the modern @-@ day axolotl . During the latest Carboniferous and Early Permian around 300 Mya , several groups , such as the dissorophids and trematopids evolved strong , robust limbs and vertebrae and became adapted to life on land while others such as the eryopids , developed into large semiaquatic predators . The dvinosaurs , a group of small aquatic temnospondyls , evolved from terrestrial ancestors in the Late Carboniferous . 
  