The tuatara is classified as a reptile, not a lizard.
They are one of the slowest growing reptiles and can reach an age of 100+ years.
Tuataras are different from other reptiles as they possess a third eye. Some scientists believe that this third eye is used to absorb ultraviolet rays to manufacture vitamin D.
Tuatara are able to maintain normal activities at temperatures as low as 7 Celcius and tempertatures over 28 Celcius the tuatara will usually die.
The body temperature of tuatara is lower than other reptiles, between 5.2-11.2 Celcius during the day. Most reptiles have body temperatures around 20 Celcius.