New Zealand: When isn’t a “lizard” a lizard?

A “lizard” isn’t a lizard when it’s a tuatara (a Māori term meaning ‘peaks on the back’). According to the relevant Wikipedia article: “Tuatara are reptiles endemic to New Zealand… which, although resembling most lizards, are part of a distinct lineage, the order Rhynchocephalia. The two species of tuatara are the only surviving members of their order, which flourished around 200 million years ago.”

What distinguishes tuatara from reptiles? “Their dentition, in which two rows of teeth in the upper jaw overlap one row on the lower jaw, is unique among living species. They are further unusual in having a pronounced photoreceptive eye, the ‘third eye’, which is thought to be involved in setting circadian and seasonal cycles. They are able to hear, although no external ear is present, and have a number of unique features in their skeleton, some of them apparently evolutionarily retained from fish.”

While the members of Sphenodon punctatus don’t normally adorn themselves with colored beads—that’s in the domain of Homo sapiens and especially Femina sapiens—the one in today’s photograph is so identified as part of the breeding and study program being carried out at the Zealandia Sanctuary in Wellington, which I visited on February 21st.

© 2015 Steven Schwartzman