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a suborder of extinct reptiles of the subclass Synaptosauria. They have been traced back to Triassic deposits, predominantly in Europe. Their body proportions and the structure of their limbs and girdle suggest that these reptiles were ancestors of the Plesiosauria. The Nothosauria, however, had comparatively small and flat skulls and webbed limbs that were not flipperlike. They were less adapted to aquatic life than the Plesiosauria. The Nothosauria were small, measuring up to 3 m long. They were predators and probably, in contrast to the Plesiosauria, fed on fish and other aquatic animals. Nevertheless, they were able to emerge onto dry land.