Tuatara from the Maori to mean “spiny back," and/or “peaks on the back” and its latin name Sphenodon punctatus, Sphenodon meaning horny beak, and punctatus being marked with minute spots or depressions, this referring to the skin texture.
Tuatara though once widespread throughout mainland New Zealand had their population numbers reduced to that of near extinction. Recent conservation and artificial rearing methods along with their release on to offshore islands have resulted in their return from near extinction.
Tuatara live for 120-150 years, grow to 600 mm, are carnivorous, their main foods being weta and land snails. For shelter, they share the burrows of Dove petrels and Buller’s shearwaters. Eggs of which 8-14 may be laid in a shallow depression about 100-125 mm deep, are covered by the female, eggs are 30-36 mm in length and have an incubation of 13-14 months.
Tuatara (200 million years) are the oldest surviving reptile and therefore
displays many primitive features. The skull displaying two complete temporal fossae (ditch), two complete fenestra (openings) one above the other just above, and behind the orbit (eye sockets). The large orbits enclosing the eyes, indicate they are highly visual predators, also the pineal eye, complete palate, and a specialised character being the teeth. that of the horny beak, and teeth being fixed to edge of jaw with the upper teeth being well developed and occurring in two parallel rows on each side between which the single row of the lower jaw teeth fit.
Of special interests are the ribs, having small hook like appendage named unicinates, that are also found on birds ribs, a further possible clue relating the theory of birds having evolved from dinosaurs.