Argentine black and white tegus are sometimes simply called black and white tegus, although this can lead to confusion as there is also a Colombian tegu (that looks similar, but is smaller and less docile). Sometimes Argentine tegus are also called giant tegus or big-headed tegus. As its common name implies, these lizards hail from Argentina and other parts of South America.
Scientific Name: Tupinambis (Salvator) merianae
Common Names: Argentine black and white tegu, black and white tegu
Adult Size: Up to 4 feet
Life Expectancy: Up to 15 years in captivity
Behavior and Temperament of Argentine Black and White Tegus
Female tegus are slightly smaller than their male counterparts, but both genders have a fairly distinctive pattern of white and black dots and stripes all over their bodies as adults. Their gender can be determined by examining the vent at the base of the tail; males have a bulge but the vent is flat in the female
Despite their large size compared to other tegus, Argentine black and white tegus enjoy a reputation for being more docile than their smaller counterparts. This is especially true of Argentine tegus that are handled regularly from a young age.
Housing Argentine Black and White Tegus
Argentine black and white tegus are big and need large and secure enclosures. Juvenile tegus can be kept in a large glass aquarium with a locking lid, but adults will need a larger specialty terrarium or a custom-built cage.
For adult Argentine tegus, plan on at least a 6-foot by 3-foot by 2-foot enclosure. Double that size for housing more than one. Unlike other lizards, taller cages are not necessary for tegus as they do not stand on their hind legs or climb trees.
A log or box for hiding should be provided and should contain slightly damp sphagnum moss, to aid with shedding and as a source of humidity for the animal's environment. Chances are your tegu will spend much of its time in this hiding spot.
Argentine tegus like to burrow, so they need a substrate that is not only absorbent and easy to clean but also allows their natural digging behavior. Cypress mulch, orchid bark, or eucalyptus mulch are the preferred substrates for tegus, although some people prefer the convenience of several layers of paper for ease of cleaning (although this can stymie the tegus' natural instinct to dig).
Avoid wood chips, ground corn cobs, or stone gravel due to the risk of ingestion. You should also avoid indoor/outdoor carpeting since it is likely to get shredded in your Argentine tegu's digging attempts and the stray threads can pose a risk of entangling its nails and toes.
Lighting and Heating
Argentine black and white tegus are diurnal (active during the day), so they need exposure to full-spectrum UVA, and UVB lighting like the sun provides. They also need a source of heat. While it is true that tegus can tolerate cooler temperatures, for proper health and digestion, daytime temperatures should be between 80 and 85 degrees Fahrenheit, with a basking spot between 100 and 110 degrees F.
Cooler nighttime temperatures are acceptable but don't allow a drastic change in temperature. Use a combination of reptile heat lamps, bulbs, ceramic heat emitters, and heat mats to reach these high temperatures but avoid hot rocks as they can cause severe burns.
Tegus have been shown to be one of the few partially endothermic (warm-blooded) lizards, having a body temperature higher than the ambient temperature at nighttime; however, unlike true endotherms such as mammals and birds, these lizards only display temperature control during their reproductive season (September to December).
Food and Water
Juvenile Argentine tegus can be fed a diet largely composed of gut-loaded crickets dusted with a calcium/vitamin supplement, along with some other feeder insects for variety, such as readily available mealworms and waxworms.
As your tegu gets older, it can be fed pinkie mice and eventually adult mice, pre-killed or frozen-thawed. But use caution if the mice you are feeding have fur as it may cause intestinal impaction (meaning the tegu can't digest the fur).
Adult Argentine black and white tegus also can have a variety of fruits and vegetables added to their diets. Canned dog food and eggs can be offered as a very occasional supplement, but be advised that too much protein will cause kidney failure. Be sure to feed your Argentine tegu their mice in a bowl or with tongs to prevent accidentally getting bitten by your hungry lizard.
Argentine black and white tegus enjoy soaking when they aren't burrowing, so be sure to provide a large shallow water dish that will fit your pet's entire body. Provide fresh water frequently, especially if your tegu defecates in its water.
Having this large water dish will also help you achieve the ideal 60 to 80 percent relative humidity in your tegu's environment (a hygrometer will help you monitor the humidity level). Misting the enclosure with water will also aid in keeping the environment the way your tegu likes it.
Choosing Your Argentine Black and White Tegu
These hardy lizards can become tame pets if handled correctly. But when you're deciding on one, there are a few things to watch out for. This is definitely a pet you want to acquire from a reputable breeder.
A sick tegu may have dry patchy skin, swelling around its nasal passages or nasal discharge, and unusual bumps in its limbs. If its eyes are cloudy or it seems lethargic, these may be signs of a sick lizard.
Common Health Problems
Calcium and phosphorous deficiencies can occur in tegus, and like other reptiles, they're susceptible to parasitic infections, which are usually only detected during a fecal exam.
They're also prone to respiratory infections, which usually happens when there is not enough humidity in the animal's enclosure. If your tegu is drooling or has swelling around its nasal passages and mouth, it may have a respiratory infection.
The most serious ailment that affects Argentine black and white tegus is a metabolic bone disease. This is the result of a lack of UVB lighting, or lack of calcium and vitamins in the diet. It's painful for the animal and can lead to swelling in the limbs and weakened bones.
If your pet stops eating, seems lethargic, shows any leg swelling, or continually has dry skin, consult a veterinarian who specializes in reptiles. These symptoms are all signs of illness, but are treatable if caught early.
Similar Species to the Argentine Black and White Tegu
If you're interested in tegus here are a few suggestions for other species you may like:
You also can check out our profiles of other lizard species.
Providing A Home for A Reptile. Merck Veterinary Manual.
Kidney Disease in Reptiles. Veterinary Information Network.
Marschang RE. Viruses infecting reptiles. Viruses. 2011;3(11):2087-2126. doi: 10.3390/v3112087
Parasitic Diseases of Reptiles. Merck Veterinary Manual.
Bacterial Disease of Reptiles. Merck Veterinary Manual.
Metabolic and Endocrine Disease of Reptiles. Merck Veterinary Manual.