only extant member of the order Rhynchocephalia of large spiny lizard-like diapsid reptiles of coastal islands off New Zealand
source: WordNet 3.0
A large iguanalike reptile (Sphenodon punctatum) formerly common in New Zealand, but now confined to certain islets near the coast. It reaches a length of two and a half feet, is dark olive-green with small white or yellowish specks on the sides, and has yellow spines along the back, except on the neck.