First aquatic reptile

According to Official Guinness Records,

The earliest predominantly aquatic reptile was Mesosaurus, which lived in South African and South American freshwater during the early Permian Period (320 to 280 million years ago).
Less than 2 m (6.56 m) long at most, it possessed a pair of slender jaws brimming with needle-like teeth, a long tail that was possibly finned, and webbed feet.

For a complete list of Unknown date records, please visit Unknown date Guinness Records in South Africa.

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