Do tuataras have teeth

The tuatara of New Zealand has a third eye, but it does not have vision capabilities. The third eye is called the parietal eye. Although it has a lens, retina and nerve connection, it is not functional as an eye. it grows on top of the reptile's head, under the skin, and is not visible.

Scientists have not been able to determine the function of this third eye, but it is thought that light falling on this third eye may influence certain biological functions such as sleep and hibernation.