A fossil called Lizzie was thought to be an early reptile

For more than 30 years, a Scottish fossil called Lizzie was considered one of the earliest known reptiles. The 345-million-year-old fossil, known as Westlothiana lizziae, was discovered in Scotland in 1984. Its claw-like digits and reptile-like legs led scientists to describe it in 1990 as the earliest land-adapted amniote, a group that includes reptiles, birds and mammals.Researchers have looked inside the crushed fossil using X-ray scans and found features that could not be seen from its surface. According to the American Museum of Natural History, the scans revealed a primitive skull, internal gills, and a fish-like mouth filled with thousands of tiny teeth. These findings show that Lizzie was not a reptile and likely lived in or around water.Why was Lizzie once considered one of the earliest reptilesFor decades, Lizzie was treated as one of the earliest known reptiles.