On another episode, we talked about species that are the last of their family tree. Well, here’s one that’s the last in its genus, in its family, even in its order.

The tuatara is a 2-ft-long resident of New Zealand. It may look like a lizard, but it diverged from modern lizards and snakes 250 million years ago, and it’s quite a different animal.

To start, it’s adapted to cold weather. The tuatara can thrive when its body temperature is just 40 degrees Fahrenheit.

It hibernates through winter, breathing as seldom as once per hour.

And it does everything else slowly, as well. The tuatara doesn’t reach sexual maturity till the ripe age of 35. Females produce eggs only once every 4 years.

Their babies hatch with a third eye on top of their heads, able to register light but not images. Its exact purpose is unknown, and after 5 years, the tuatara’s skin grows over it.

Its teeth are unusual, too. Two top rows overlap a single bottom row and saw together to eat their food. However, they’re not really teeth but bony projections from the jaw.

When the tuatara reaches old age, which could be well over 100 years, its teeth have completely worn off. And it has to switch to a soft food diet of worms and larvae.

The tuatara, sometimes called a living fossil, has even appeared on New Zealand’s money.

In nearly every way, this remarkably persistent animal is a “one of a kind.”