What is "seymouria"

Seymouria was a reptile-like tetrapod from the early Permian of North America and Europe (approximately 280 to 270 million years ago). It was small, only 2 ft (60 cm) long. Seymouria was well adapted to life on land, with many reptilian features—so many, in fact, that it was first thought to be a primitive reptile.