The largest species from the tegu is found in Argentina which is commonly known as the Argentine Giant Tegu. Tegus are lizards belonging to the Teiidae family that are mainly endemic to the Central and South America. This black and white colored Argentine tegu is scientifically called as Tupinambis merianae which prefers to live in the tropical rainforests of Argentina. In the suitable environment, the Argentine black and white tegu can reach up to a size of 4-4.5ft including the tail in the male and the female reaching a smaller 3ft in length. Apart from the forests of the Eastern Argentina, Argentine giant tegus are also found in Uruguay, Bolivia and Southern Brazil.

Being an omnivorous lizard in nature, the Argentine black and white tegu loves to eat insects, spiders and wild fruits and seeds. This tegu becomes fully adult at the age of 3 years old and starts breeding. The female Argentine Giant Tegu builds a nest in which she lays a clutch of roughly 36-70 eggs.  Normal life span of the Argentine black and white tegu includes 15-20 years.

Argentine black and white tegu which is the largest tegu of the world is also kept under captivation and is considered as a good pet. It becomes attached to the owner and is generally quite docile as adults.