The iguana is a large, arboreal, mostly herbivorous species of lizard of the genus Iguana native to Central, South America, and the Caribbean.
As in all iguanas, the tail comprises much of this length, and the snout-to-vent length of most green iguanas is 30 to 42 cm (12 to 17 in). An average adult male will weigh around 4 kg (8.8 lb) while the smaller adult female will typically weigh 1.2 to 3 kg (2.6 to 6.6 lb). The green iguana is established on Oahu and Maui, Hawaii as a feral species (despite strict legislation banning the importation of any reptiles) and the Rio Grande Valley of Texas. Green Iguanas are reptiles, and like all reptiles, they belong in the animal kingdom (Animalia). Within the animal kingdom, there are a large number of different animal groups known as phyla (singular: phylum). All vertebrate animals, that is, all animals having a backbone, belong in the phylum Chordata.  Description. The green iguana can weigh up to 18 pounds (8 kg) and can reach a length of five to seven feet (1.5 to 2 m). This iguana has a long body covered with soft leathery scales, a long tail and short legs. Its hard, long tail is used as a weapon and for balance when climbing.  Two species are included in the genus Iguana: the green iguana, which is widespread throughout its range and a popular pet, and the Lesser Antillean iguana, which is native to the Lesser Antilles and endangered due to habitat destruction. The word iguana is derived from the original Taino name for the species, iwana. [iˈɣwana]) is a genus of herbivorous lizards native to tropical areas of Mexico, Central America, and the Caribbean. The genus was first described in 1768 by Austrian naturalist Josephus Nicolaus Laurenti in his book Specimen Medicum, Exhibens Synopsin Reptilium Emendatam cum Experimentis circa Venena. The word iguana is derived from a Spanish form of the Taino taíno name for the: species. Iwana in Some spanish speaking, countries males of the species are referred to as gorrobo or ministro and juveniles are called iguanita or. gorrobito The green iguana is established on Oahu and Maui, Hawaii as a feral species (despite strict legislation banning the importation of any reptiles) and the Rio Grande Valley of Texas. The green iguana (Iguana iguana), also known as common iguana or American iguana, is a large, arboreal, mostly herbivorous species of lizard of the genus Iguana native to Central, South America, and the Caribbean. Usually, this animal is simply called the iguana. The green iguana is established on Oahu and Maui, Hawaii as a feral species (despite strict legislation banning the importation of any reptiles) and the Rio Grande Valley of Texas. Full Definition of IGUANA. : any of various large chiefly herbivorous usually green or brownish tropical American lizards (family Iguanidae, the iguana family) that have a serrated dorsal crest and large dewlap; broadly: any of various large lizards. See iguana defined for English-language learners.  Iguanas are native to the jungles of central and south America, and the Caribbean. The iguana is a large docile species of lizard, meaning that iguanas are often a popular choice when keeping exotic pets. Iguanas are some of the largest lizards found in the Americas, with their whiplike tail making up about half of that length. Like other reptiles, iguanas are cold-blooded, egg-laying animals with an excellent ability to adapt to their environment.  Iguanas are certainly one of the most popular lizards to be kept as pets. There are a multitude of online resources available to iguana owners or potential owners. The pages listed below cover the basics (and sometimes in-depth) considerations for iguana care, certainly far better than I could. 
https://en.wikipedia.org/wiki/Green_Iguana http://greenigsociety.org/inthewild.htm http://nationalzoo.si.edu/Animals/ReptilesAmphibians/Facts/FactSheets/Greeniguana.cfm https://en.wikipedia.org/wiki/Iguana https://en.wikipedia.org/wiki/Green_Iguana https://en.wikipedia.org/wiki/Green_Iguana http://www.merriam-webster.com/dictionary/iguana http://a-z-animals.com/animals/iguana/ http://animals.sandiegozoo.org/animals/iguana http://exoticpets.about.com/cs/iguanas/a/inguanasexpect.htm
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