The first tuatara to hatch in the wild on mainland New Zealand in two centuries has been found in Wellington.
The hatchling, now about a month old and eight centimetres long, was found during routine maintenance work in the Karori Wildlife Sanctuary.
Sanctuary staff suspect the new arrival was probably one of a clutch of eggs laid 16 months ago.
Conservation manager Raewyn Empson was "absolutely thrilled" by the discovery tuatara were breeding in the wild on the mainland.
"This is an extremely significant discovery," she said.
"It means we have successfully re-established a breeding population back on the mainland, which is a massive breakthrough for New Zealand conservation."
Though the tuatara was the only one of his generation found so far, he probably wasn't alone, she said.
"He is unlikely to be the only baby to have hatched this season, but seeing him was an incredible fluke.
"We certainly didn't expect to see them so soon - perhaps not until they were adults," she said.
The hatchling came from one of the 200 tuatara moved to the sanctuary in the last four years from Takapourewa/Stephens Island in Cook Strait.
To live to adulthood, the lizard and his kin must avoid being eaten by other, bigger tuatara, as well as birds such as the morepork, kingfisher and weka.