Kingdom: Animalia
Phylum: Chordata
Order: Rhynchocephalia
Family: Sphenodontidae
Subfamily: Sphenodontinae
Genus: Sphenodon
Species: Sphenodon guntheri
Common name:  Brothers Island tuatara, Gunther's tuatara

The tuatara is a reptile that is endemic to New Zealand which, though it resembles most lizards, is part of a distinct lineage, order Rhynchocephalia. There are three different species of Tuatara in New Zealand:

Northern Tuatara (Sphenodon punctatus punctatus)
Cook Strait Tuatara (Sphenodon punctatus)
Brothers Island Tuatara (Sphenodon guntheri)

Sphenodon guntheri (Brother Islands tuatara)  was not recognised until 1989. Sphenodon guntheri (Brothers Island tuatara) are characteristically smaller and have longer reproductive cycles than Sphenodon punctatus (Spotted tuatara).
Sphenodon guntheri inhabits the North Brother Island and Matiu/Somes Islands in Cook Strait, New Zealand (41°06? S, 174°26? E). Only a few hundred individuals remain on North Brother Island.

Sphenodon guntheri is one of the few reptiles with the ability to thrive in cooler conditions. They are nocturnal and physically capable of withstanding temperatures as low as 9°C, with humidity in the range of 70 to 80%. High humidity and low temperatures allow tuataras to maintain healthy shed cycles and live longer life spans, due to their effects on the heart and metabolic rates. During the day, most individuals inhabit burrows along cliff faces. Their burrows can measure about 5 meters in length and 30 centimetres in depth and are sometimes taken over by previous inhabitants. Burrows are typically found in open areas featuring low coastal vegetation, and usually, offer both shade and sunlight to aid in heat regulation. Certain cliffs and other areas of the island that provide different types of terrain are often inhabited by birds or other animals that can compete with the tuatara for territory. (Cree, 1994; Lutz, 2005; Mitchell, et al., 2008; Nelson, et al., 2002a; Ramstad, et al., 2007)

Photographed at Southland's museum breeding enclosure.
Sphenodon guntheri Tuatara-002 1 .JPG

Sphenodon guntheri Tuatara-002.JPG

Photographed at EcoWorld Aquarium, Picton
Sphenodon guntheri Brothers Island tuatara.JPG

Sphenodon guntheri Brothers Island tuatara-001.JPG

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Sphenodon guntheri Brother Islands tuatara .JPG  
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