Classification: Introduced Species. They are a consistently problematic invasive species in Florida counties, most likely as a result of escaped or released species from the early 2000s pet trade. Previous studies have found that the differing weather and climate patterns far outside of their natural habitat range do not prevent adult Argentine Black and White Tegus from surviving in diverse areas across the United States, furthering concerns about their invasive status. In the wild, tegus habitat both forested and open plain environments, widening their potential invasive range.

In Florida Argentine black and white tegus have escaped from the pet trade and are now an invasive species in Florida, Georgia, and South Carolina. The first sighting of S. merianae in Berkeley County, South Carolina was on 10 September 2020. Eight total sightings in South Carolina had been recorded as of 10 September 2020.

Description: As a hatchling, Salvator merianae has an emerald green color from the tip of its snout to midway down its 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 to the body change to areas of weak speckling. Fewer solid bands indicates 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. Adult males are much larger than the females and can reach 3 feet in length at maturity. They may continue to grow to lengths of 4 to 4.5 feet. The females are much smaller, but may grow up to 3 feet in length from nose to tail. They have beaded skin and stripes running down their bodies. Adult females can reach a weight of 5.5 to 15.4 lbs. The skull is heavily built with a large facial process of the maxilla, a single premaxilla, paired nasals, a single frontal bone and two parietal bones separated by the sagittal suture. Biomechanical analyses suggest the posterior processes of the parietal might be important for dealing with torsional loads due to posterior biting on one side. In the large adults, the posterior teeth are larger and more rounded than the anterior teeth.

Habitat: Tegus have also been found in scrub and wet habitats such as flooded savannas, canals, ponds, and streams. They largely seem indiscriminate of habitat type as long as they have the ability to burrow.

Range: Salvator merianae (once known as Tupinambis merianae) aka the Argentine Black and White Tegu is a large reptile native to South America. There are significant populations of Argentine Black and White Tegus in the southern United States and the Brazilian coast.

Found in these States: FL

Diet: Tegus are omnivorous. Juvenile tegus in the wild have been observed to eat a wide range of invertebrates including insects, annelids, crustaceans,[16] spiders and snails.[17] They also eat fruits and seeds. As they mature, their diet becomes more generalized, and plant consumption increases. They may seek out eggs from other reptiles' and from birds' nests and will eat small birds and other vertebrates such as fish, anurans, other lizards, snakes and small mammals (such as rodents). In adulthood, tegus continue to eat insects and wild fruits and it is assumed that such components include desirable or essential nutrients. They also can hunt larger prey such as armadillos.

As adults, they have blunted teeth and exaggerated lateral pterygoid muscles which allow them to be generalist feeders. Tegus are notorious egg predators which makes them a concerning rising predator of sea turtles, alligators, and crocodiles as their invasive populations spread across the United States. Tegus will eat anything from plants to hatchlings, but their diet varies by season. Small vertebrate prey is more common in the spring while plant life and invertebrates are more commonly consumed in the summer.

Reproduction: Squamate reptiles like snakes and lizards tend to rely on chemical cues to search for potential mates in their environments. The Argentine black and white tegu exhibits similar behavior, such as a marked "pausing and turning" as they trail in the spring. In particular, female tegus exhibit stronger trailing behavior than males, following scent trails more intensely and expressing a more sensitive response to mating specific chemical odors. They also exhibit more decisive behavior, demonstrating a common vertebrate trend of female reproduction being the defining factor in influencing population size. Knowledge of this behavior is currently being explored as a strategic avenue to inhibit the current rise of the tegu as an invasive species. Prioritizing the removal of female tegus from the environment can potentially be a more effective way to curb these invasive populations. Tegus are a burrowing species in both their native and invasive habitats, especially during the winter. They mate during the spring after hibernating when their mating hormones are at their peak. During the spring, male Argentine tegus exhibit scent-marking behaviors such as delineating territory with gland scents.

During maternal seasons, female Argentine black and white tegus build nests out of dry grass, small branches, and leaves in order to maintain optimal temperature and humidity levels. Egg incubation lasts for an average of sixty-four days, with a range of forty to seventy-five days depending on incubation temperature and other extenuating factors.

Status: The Black and White Tegu is listed as Least Concern in view of its wide distribution, tolerance of a broad range of habitats, large population, and because it is unlikely to be undergoing significant population declines to qualify for listing in a more threatened category. Since this species is hunted for its skins and for local consumption, it is recommended that research is undertaken to ensure that any population declines are noted, and trade and harvest management plans are put in place where needed.

Subspecies:
   Salvator merianae buzioensis
   Salvator merianae merianae
   Salvator merianae sebastiani

Taxonomy: