Diplocaulus ("double caul") is a genus of prehistoric amphibian from the Permian period of North America. It is one of the largest of its group, the lemnospondyls, and is well known for its boomerang-like head. The tips of this head were attached to the body by flaps of skin. The head is theorized to have acted like a fin, helping it glide through the water. Another theory states that the head had more defensive purpose, making it harder for predators to swallow it due to the width of the head. Remains that may belong to Diplocaulus have been found from the Late Permian period of Morocco, which may indicate that it is the youngest known occurrence of any species of lemnospondyl.
In The Land Before Time
Diplocaulus briefly appears in one of the minigames in the game The Land Before Time Animated Moviebook.