[9] As a hatchling, Salvator merianae has an emerald green color from the tip of its snout to midway down its neck, with black markings.

[citation needed] Adult males are much larger than the females and can reach 3 feet (91 cm) in length at maturity.

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.

Juvenile tegus in the wild have been observed to eat a wide range of invertebrates including insects, annelids, crustaceans,[20] spiders and snails.

[citation needed] In adulthood, tegus continue to eat insects and wild fruits and it is assumed that such components include desirable or essential nutrients.

[20] However, there is evidence that, as in most husbandry of carnivores, it is good practice to cook most of the egg in the diet, so as to denature the protein avidin that occurs in the albumen.

In captivity, they have been observed eating various feeder insects like mealworms, superworms, earthworms, silkworms, crickets and cockroaches, as well as vertebrate prey like mice, rats, fish, turkey (offered in a ground form), rabbit, quail and chicks.

Like all lizards, blue tegus need a properly balanced diet; incomplete prey items such as insects or ground meat require dusting with a mineral/multi-vitamin supplement.

A known predator of the Argentine black and white tegu is the lesser grison (Galictis cuja), a mustelid related to weasels.

Pigmentation of the ventral portion of the body occurs between days fifty-seven and sixty, characterized by individualized spot patterns.

Those with a higher bite force also exhibit less escape responses and tend to be slower, displaying a trade off of fight or flight abilities, but also have the advantage of minimizing risk of energy by reducing the threshold for engagement in an aggressive encounter.

This fight or flight trade off is more commonly observed in mammals rather than reptiles, and may be present in tegus because of an increase in head mass (correlated to stronger biting behavior) that makes it difficult to maneuver quickly.

In their home territory, Argentine tegus are generally less aggressive (less likely to display arching behavior) and are less likely to attempt escape regardless of size or bite force.

A study using skin lipids indicates chemical cues can be used to modify movements of invasive reptiles in their non-native range, which could be useful in management strategies.

[31] The Argentine black and white tegu exhibits similar behavior, such as a marked "pausing and turning" as they trail in the spring.

They also exhibit more decisive behavior, demonstrating a common vertebrate trend of female reproduction being the defining factor in influencing population size.

[citation needed] 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.

Notably, they mature early, reproduce annually, have large clutch sizes, and a relatively long life span compared to other competing species.

[17] Tegus in their native environment spend most of the colder months hibernating in their burrows without feeding but emerge in the spring for their mating season.

However, Argentine tegus only display this behavior for part of the year and behave as ectotherms for the rest (sunbathing, temperature reliant on environment).

They are highly active throughout the day during warmer months (such as participating in reproductive endothermy during the spring) and experience drastic metabolic suppression during the winter.

Because of its weight and heavy girth, it has unique modifications to its skeletal gait that help map the evolutionary history of the non-mammalian musculoskeletal structure.

Some believe it is a mutation of the Argentine black and white tegu, while others, including the original importer, believe it is sufficiently different to classified as its own species, or a subspecies.

[53] The Argentine black and white tegu has been a particular threat to native birds and reptiles that build nests or burrows on the ground.

Notably, they exhibit a particular type of both predatory and competitive behavior known as intraguild predation, which worsens their invasive effect on wildlife: Argentine tegus will pursue and kill – but not eat – other native reptiles.

Efforts such as placing traps or local hunting have been largely unsuccessful in reducing their bad effects in the non-native environments.

[32] Because of their invasive threat to native and imperiled species, population containment initiatives have been a priority in the past ten years, leading to the extraction of nearly 3,300 tegus from Miami-Dade County alone.

Unfortunately tegu culling efforts have had little effect: Historically, tegus survived brutal leather-trade harvests in their native environment, demonstrating that they are a remarkably resilient species.

As an alternative to killing them, the Florida Fish and Wildlife Conservation Commission (FWC) staff offer to take control and maintain this species by capturing and removing tegus from the environment.

[citation needed] S. merianae and T. teguixin can be distinguished by skin texture and scale count: In the ecotone between the arid Chaco and the Espinal of central Argentina, they are known to naturally hybridise with the red tegu (Salvator rufescens) with a stable hybrid zone.