Tuatara means 'peaks on the back' in Māori, referring to the distinctive ridge of spines down their backs.
Once widespread, tuatara have been wiped out on the mainland by introduced predators. They have survived in the wild only on isolated pest-free offshore islands.
Tuatara grow very slowly and can live for 100 years or more.
Their teeth are part of the jaw bone and can't grow back when they wear down.