Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Iguania
Family: Iguanidae
Genus: Iguana
Species: I. iguana
Binomial name: Iguana iguana
Synonyms: Iguana iguana rhinolopha, Lacerta Igvana, Hypsilophus tuberculatus, Iguana hernandessi, Iguana iguana rhinolopha, Hypsilophus Rhinolophus, Iguana rhinolopha, Iguana rhinolophus
Common names: Green Iguana, American iguana 

Iguana iguana is a large, diurnal, arboreal, mostly herbivorous species of lizard native to Central and South America. 
In New Zealand (2018) they are currently at Wellington Zoo, Ti Point Reptile Park (Leigh), Willowbank Wildlife Reserve (Christchurch, Natureland Wild Life Trust (Nelson) and the Auckland Zoo. 

The green iguana is a large lizard. Despite their name, green iguanas can come in different colours. Adults typically grow to >1.7 m in length from head to tail. As in all iguanas, the tail comprises much of this length, and the snout-to-vent length of most green iguanas are >42 cm. An average adult male will weigh around 4 kg while the smaller adult female will typically weigh >3 kg. A few large males can reach or exceed 6 to 8 kg in weight and 2 m long.
Green iguanas possess a row of spines along their backs and along their tails, which helps to protect them from predators. Their whip-like tails can be used to deliver painful strikes and like many other lizards, when grabbed by the tail, the iguana can allow it to break, so it can escape and eventually regenerate a new one. In addition, iguanas have a well-developed dewlap, which helps regulate their body temperature. This dewlap is used in courtships and territorial displays. 
Green iguanas have a white photosensory organ on the top of their heads called the parietal eye, in contrast to most other lizards that have lost this primitive feature. This "eye" has only a rudimentary retina and lens and cannot form images but is sensitive to changes in light and dark and can detect movement. This helps the iguana detect predators stalking it from above.
The Green Iguana is classed as an invasive species in the Caribbean, Fuji, United States and Hawaii.

1-Iguana iguana 04.jpg

Green iguanas can come in different colours
1-Green Iguana 010.jpg 

lizard guanas have a well-developed dewlap, which helps regulate their body temperature. 
1-green iguana Male with spines and dewlap.JPG


Thanks to Wikipedia for text and information:

https://creativecommons.org/licenses/by-sa/3.0/ http://www.terrain.net.nz/uploads/images/Te%20Henui/Faunatwo/1-green%20iguana%20Male%20with%20spines%20and%20dewlap.JPG