Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Sphenodontia
Family: Sphenodontidae
Genus: Sphenodon
Species: punctatus
The Tuatara has:
- Scales
- Claws
- Spines
- Tale
- 4 appandages with slightly webbed feet
- No open ear holes, do have a middle ear cavity
Skull: The tip of the upper jaw is beak-like and separated from the remainder of the jaw
by a notch. They have a single row of teeth on bottom jaw and double rows in the upper
jaw. This tooth arrangement is specific to the Tuatara because it is not found in other reptiles. The spine is made up of hourglass-shaped amphicoelous vertebrae. This is unique to the Tuatara within the amniotes. The Tuatara has gastralias, or rib-like bones.
The males do not have a penis but an organ that is like it. The female reproductive organ is called a cloaca. It takes 10-20 years for them to reach sexual maturity. Mating occurs in midsummer, but the females only mate and lay eggs once every 4 years. During courtship, a male makes his skin darker, raises his crest, and parades over toward the female. She then will allow him to mount her, or invite him into her burrow. It will take between 1 and 3 years to provide eggs with yolk and up to 7 months to form the shell. It then takes 12-15 months from copulation to hatching.
The lungs are spongy like, but helps with gas exchange. The Tuatara has 2 lungs and the
respitory system like that of a human.
They have a 3 chambered heart and a double loop circulatory system. One loop brings
blood to and from the rest of body.
Tuatara are a carnivorous species, eating bugs and smaller animals. Otherwise they have
the normal reptilian digestive system.
The third eye that is special to the Tuatara is a complex organ at the top of the brain. It
senses the level of sunlight. They have great senses and a normal nervous system of a reptile.
In the first six months of a Tuatara's life, it has a visible parietal eye that is light sensitive, drawing in ultraviolet rays. Believed that this occurs because the Tuatara uses the ultraviolet rays to make vitamin D for growth. After six months, scales cover eye.
They are a living fossil and excellent swimmers.
Adults are nocturnal and live on ground because they are known to eat their babies.
Young live in trees and are diurnal 9active during the day).
In the wild, they are known to stop reproducing around 60 years. However, in captivity they are known to continually reproduce much older. For example, Henry, a 111-year-old Tuatara, became a father in 2009 for the first time.
