According to a report by Sky News, the reptile known as a baby 'Tuatara,' has three eyes, but is said to mostly resemble a lizard.
It was found by staff at the Karori Wildlife Sanctuary, but until then had not been spotted in the country for around 200 years.
Tuatara measure up to 80cm when fully grown and can live for up to 60 years.
They are the last lizard-like species to have walked the earth with dinosaurs 225 million years ago, according to zoologists.
They are said to live off insects and lizards, but also shockingly eat their own young.
They are a mainly nocturnal species, and are able to regrow their tales if they become shredded.
They are sometimes referred to as "living fossils", as their appearance has not changed since the dinosaur age.
There are an estimated 50,000 of them living in the wild, but this is the first time one has been found on the mainland for 200 years.
Evolutionists are particularly interested in the species as they are related to snake and lizard families.
According to Conservation Manager, Raewyn Empson, "We are all absolutely thrilled with this discovery."