Tuatara are reptiles endemic to New Zealand. Although resembling most lizards, they are part of a distinct lineage, the order Rhynchocephalia. The single species of tuatara is the only surviving member of its order, which flourished around 200 million years ago. Their name derives from the Māori language, and means “peaks on the back”. Their most recent common ancestor with any other extant group is with the squamates (lizards and snakes). The average lifespan is about 60 years, but they can live to be well over 100 years old. Some experts believe that captive tuatara could live as long as 200 years.