Diplocaulus

Diplocaulus Temporal range: 299–251 Ma PreЄ Є O S D C P T J K Pg N Early to Late Permian
Diplocaulus magnicornus
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subclass:	†Lepospondyli
Order:	†Nectridea
Family:	†Diplocaulidae
Genus:	†Diplocaulus Cope, 1877
Species
†D. salamandroides Cope, 1877(type) †D. magnicornis Cope, 1882  ?†D. brevirostris Olson, 1951  ?†D. recurvatus Olson, 1952  ?†D. minimus Dutuit, 1988
Synonyms
Genus-level: Permoplatyops Case, 1946 Species-level: Diplocaulus limbatus Cope, 1895 Diplocaulus copei Broili, 1902 Diplocaulus pusillus Broili, 1904 Permoplatyops parvus (Williston, 1918 [originally Platyops parvus]) Diplocaulus parvus Olson, 1972

Genus-level:

Species-level:

Diplocaulus (meaning "double caul") is an extinct genus of lepospondyl amphibians from the Permian period of North America. It is one of the largest lepospondyls, with a distinctive boomerang-shaped skull. Remains attributed to Diplocaulus have been found from the Late Permian of Morocco and represent the youngest known occurrence of a lepospondyl.

Diplocaulus had a stocky, salamander-like body, but was relatively large, reaching up to 1 m (3.3 ft) in length. Its most distinctive features were the long protrusions on the sides of its skull, giving the head a boomerang shape. Judging from its weak limbs and relatively short tail, it is presumed to have swum with an up-and-down movement of its body, similar to modern whales and dolphins. The wide head could have acted like a fin, helping the creature glide through the water. Another possibility is that the shape was defensive, since even a large predator would have a hard time trying to swallow a creature with such a wide head. Rare trace fossils of Diplocaulus-like amphibians show that the tips of the boomerang-shaped head were connected to the body by flaps of skin.

A close relative of Diplocaulus is Diploceraspis.

Skull of Diplocaulus magnicornis at the Museum für Naturkunde Berlin

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