Kotlassia

a genus of extinct amphibians of the subclass Batrachosauria, which existed during the late Permian. The body was approximately 125 cm long. The skull was flat, broad, and shortened, and the teeth had plicated dentin, as did those of the labyrinthodonts. Members of the genus Kotlassia were similar in the structure of their limbs, girdles, and spine (with its well-developed cervical region) to reptiles and were formerly considered to be reptiles. The back of Kotlassia, like that of crocodiles, was covered by an armor of bony plates. They fed mainly on fish. Skeletons of Kotlassia have been found along the Severnaia Dvina River, near the city of Kotlas (hence the name).