(Tupinambis), any of about seven large, carnivorous, tropical South American lizards of the family Teiidae. The background colour of most species is black. Some have yellow, reddish, or white bands across the back, whereas others have broad lines extending down the body with irregular markings on the top surface. The scales of the tegu are small, square, and arranged in regular rings around the body. This large lizard has a streamlined body shape with a long tail and powerful legs. Most species are roughly 1 metre (3 feet) long; however, one species, T. merianae, reaches 1.3 metres (about 4 feet) in total length. Like other teiids, the tegu uses its tongue and Jacobson's organ (a chemoreceptor organ located on the roof of its mouth) to detect and discriminate chemical cues associated with prey and other individual lizards.
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