Iguana is a genus of lizard native to tropical areas of Central and South America and the Caribbean.The genus Iguana includes two species: the Green Iguana, which is widespread throughout its range and a popular pet, and the Lesser Antillean Iguana, which is endemic to the Lesser Antilles and endangered due to habitat destruction.
The two species of lizard within the genus Iguana possess a dewlap, a row of spines running down their back to their tail, and a third "eye" on their head. This eye is known as the parietal eye, visible as a pale scale on the top of the head. Behind their neck are small scales which resemble spikes, known as tuberculate scales. These scales may be a variety of colors and are not always visible from close distances. They have a large round scale on their cheek known as a subtympanic shield.
Iguanas have excellent vision and are able to see shapes, shadows, colors and movement at long distances.
They respond to visual stimulus of colors such as orange, yellow, pink, and in rare cases blue as food substances.
Source: en.wikipedia.org/wiki/Iguana - 26.03.2010
Interesting carapaces and scale-dresses are protection and also an especial ornament of many reptiles.
This Iguana is a beautiful example for this species.