The reptiles and amphibians of New Zealand are almost completely endemic. All amphibians are unique to the country and 99% of the reptiles are as well.
There are many unique and interesting creatures to be found, such as the tuatara. The tuatara is considered to be a "living fossil" because it is the only surviving species of the order RHYNCHOCEPHALIA. Althought it may resemble a lizard, the tuatara differs from these by having a complete lower temporal arch on its skull, behind the eye. It also has a third eye on the top of its head, which serves as a light detector. They can grow to be 60cm in length, with spines on it's back. The tuatara idealy lives in temperatures ranging from 12 to 17 degrees celcius. This is by far the coldest temperature for any reptile to reach its peak of activity. This may account for the slow bodily processes and growth rates. Tuatara take 20 years to mature and may live to be more than 100 years old.
The frogs of New Zealand are another example of a "living fossil". These frogs are thought to be the most primitive frogs in the world. They lack many features found in other frogs such as ear drums, vocal sacks, webbing between toes and hind feet, as well as no tadpole stage. They also have "tail wagging muscles", but no tail.