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a genus of fossil amphibians of the subclass Ba-trachosauria. Remains have been found in Lower Permian deposits near the city of Seymour, Texas, USA. The small amphibians measured about 1 m long and had a flat, broad head and a rounded snout. Seymouria were terrestrial animals. The structure of the calvaria, palate, jaws, and teeth closely relates the Seymouria to the amphibian labyrinthodonts. The limbs, cingu-la, and spine are structurally similar to those of the Cotylosau-ria, that is, the reptile group to which the Seymouria were earlier ascribed. Remains of the genus and other genera closely related to the Seymouria have been found in the USSR. Together with the Seymouria, they are combined in the group Seymouri-amorpha—the probable ancestors of reptiles.