Argentine giant tegu, Black and white tegu, Huge tegu, Lagarto overo (Spanish)
The Argentine black and white tegu (Salvator merianae) is a large species of lizard in the family Teiidae. The species is the largest of the "tegu lizards". This species is popular as pets because it has unusually high intelligence and can also be house-broken. It is the only known reptile to be partly endothermic.
As hatchlings, these tegus have an emerald green color from the tip of their snout to midway down their neck with black markings. The emerald green becomes black several months after shedding. As a young tegu, the tail is banded yellow and black; as it ages, the solid yellow bands nearest the body change to areas of weak speckling. Fewer solid bands indicate an older animal. A tegu can drop a section of its tail as a distraction if attacked. The tail is also used as a weapon to swipe at an aggressor; even a half-hearted swipe can leave a bruise. The females are usually much smaller than males. They have beaded skin and stripes running down their bodies.
Argentine black and white tegus are found in eastern and central South America. They live in tropical dry forests and rainforests, shrubland, and agricultural areas.
Argentine black and white tegus are generally solitary and diurnal reptiles. They are terrestrial but young tegus are more arboreal and often spend time in trees to stay safe from predators. Tegus usually spend their time foraging or basking in the sun to regulate their body temperature. During the winter months, they brumate (hibernation-like state), usually in groups. Tegus are capable of running at high speeds and can run bipedally for short distances. They often use this method in territorial defense, with their mouth open and front legs held wide to look more threatening. Tegus can be aggressive. Their bite can be painful and damaging due to their strong jaws and sharp teeth. They do not produce venom. They will perform a threat display if they are upset or stressed. The first stage is huffing, or very heavy breathing, which means be careful. Then the animal starts lashing its tail, somewhat like a moving snake. In the wild, after that tegus may stamp their front feet, this performance is also known as a "dance". If these hints are ignored, then the tegu can charge and may bite.
Argentine black and white tegus are omnivorous. Juveniles in the wild consume a wide range of invertebrates, including insects, spiders, and snails. They also eat fruits and seeds. As they grow they become more predatory. They may seek out eggs from other reptiles and from birds' nests and will eat small birds, vertebrates, insects, and wild fruits.
The breeding season for Argentine black and white tegus starts in spring, right after hibernation. After mating females start building nests in which they lay up to 30 eggs. Tegu females are very protective of their nests and will attack any predator. The incubation period usually lasts around 40 to 60 days. The young are fully developed at hatching and grow up very quickly. They usually stay with their mother for some time until they grow up enough to take care of themselves.
There are no major threats to Argentine black and white tegus at present. However, these lizards are hunted sometimes for their skin and meat. They are also collected for the commercial pet trade.
According to IUCN, the Argentine black and white tegu is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.
Argentine black and white tegus eat fruits and thus play an important role in dispersing seeds throughout the habitat they live in.
