Argentine black and white tegu
Salvator merianae
Photo: Argentine black and white tegu (Salvator merianae) male Vicente Lopez · Charles J. Sharp · CC BY-SA 4.0 · Changes and credits
These guides provide general husbandry information and do not replace veterinary assessment. If your animal shows symptoms or its condition worsens, contact a veterinarian experienced with exotic animals.
- Warm zone
- Basking surface: 52–57 °C
- Cool zone
- Cool air: 24–29 °C
These notices cover the cited provisions, not every possible national or local rule. Check additional requirements with the competent authority.
Description
Salvator merianae is a large South American lizard with a powerful body and black-and-white pattern. Mainly terrestrial, it digs and uses its forked tongue to investigate scents and locate food. Its natural diet is omnivorous and changes with age; populations in seasonal regions reduce activity during colder months.
Behaviour
Observe the individual’s behaviour and limit handling.
Housing together
House animals individually with their own water, food and retreats. Before a breeding introduction, prepare separate accommodation and watch the encounter. Stop persistent pursuit or exclusion from retreats and food; do not leave individuals together when they cannot withdraw from the partner.
Enclosure and climate
Provide ample usable floor space, deep digging substrate and a humid retreat. The basking area must warm the body evenly while leaving an accessible cool area.
Setup
Make the humid retreat openable so bedding can be checked without destroying the burrow.
Warm area, cool area and hides
If heating is specified, place it at one end and distribute hides between that area and the cool side. Choose openings and internal space suitable for the body; after adding bedding, check that entrances remain clear. Set the dish on a stable base and leave routes between retreats; use low supports only where suitable for the species.
Burrowing and furnishing stability
Secure rock and platform supports to the floor before adding substrate to the specified depth. Leave a continuous digging area and remove material beside bases as a test: furnishings must remain supported. Complete the digging layer before adjusting lamp heights, as it changes the height the animal can reach.
Testing and access
Connect specified heat sources to compatible thermostats and guard against contact. Secure probes according to device instructions; measure air at resting sites and heated surfaces separately with independent instruments. In housing with water, also check water temperature and quality: one zone’s thermostat does not control the others.
With the complete enclosure running, record day and night readings and compare them with the sheet. Test doors, cable openings and cleaning access, keeping vents clear. Change one variable at a time and recheck after each adjustment.
Lighting and UVB
Zone 3: open or partial sun exposure; ecological UVI band 1–2.6.
At the exposed position aim for approximately UVI 3–4, measured at the back or head. The animal must choose its exposure and reach UVI 0 retreats. This local target differs from the Ferguson ecological band and should not be maintained everywhere throughout the day.
UVB is essential in indoor housing. Outdoors, direct sunlight can provide it if shade is always accessible. Select the lamp to achieve the appropriate UVI at the positions the animal uses.
UVA is recommended as part of daytime lighting, including when UVB has not been shown to be indispensable. Check the UVB source’s spectrum, as it may already emit UVA: a second lamp is not automatically necessary.
Linear UVB tube with reflector. Indicative UVB percentage stated on the lamp: 5–7%; final selection depends on UVI achieved at the actual distance.
For maintenance, a cycle of approximately 12 hours of light and 12 hours of darkness can serve as an initial reference. Use a timer to switch lights off at night, and keep retreats available so the animal can withdraw from light during the day. Adapt day length to species and origin, following the specific guidance for seasonal care and breeding.
Light in the animal’s daily life
Size the usable patch for the adult: the tube centre alone does not establish coverage. Measure several positions along the body and retain a screened burrow.
An example layout in the enclosure
To make the layout concrete, take housing measuring 240 × 120 × 120 cm, using the first dimensional configuration in the sheet. This is a mounting example: retain the conditions and any alternatives attached to the stated minimum.
In a wooden enclosure with internal lighting, imagine the tube 115 cm above the floor and the back or head at 75 cm. The geometric distance is therefore 40 cm. The branch or platform lies below animal height, according to body size. Place lighting over one side, with a route to fully screened retreats.
In a glass enclosure with a mesh roof, retain the same animal height and imagine the tube 5 cm above the mesh: distance becomes 50 cm. Mesh attenuates UV variably; ordinary glass roofs block UVB. Increasing the percentage alone is insufficient: measure beneath the mesh and adjust height, output or layout as needed.
These distances describe the example, not a safe clearance for every lamp. Select the source and adjust mounting until approximately UVI 3–4 is measured at animal height in the exposed position. Also respect the minimum clearance specified for the model used. Recheck with furnishings, guards and mesh installed, including the highest reachable points and animal growth.
Choosing and checking lighting
First define the patch that should illuminate the whole body and the route to a screened retreat. For a broad patch, select a linear tube with reflector; consider a compact only if its useful patch covers the body and leaves an accessible gradient. Check model, output, reflector and mounting distance, then compare measured UVI with the species target. Label UVB percentage alone cannot determine distance and intensity.
The decisive check uses a UVI metre facing the source at animal height. Check the centre and edges of the exposed patch, the highest supports and retreats, which must allow withdrawal from UV. Repeat after moving equipment, changing lamps and plant growth. Without a metre, use the manufacturer’s instructions and measurements for the exact configuration, including safety clearances.
When UVB or UVA are absent
If the UVB source fails, restore the installation and recheck the exposed area. Oral D3 may be considered as temporary support but is not a complete or universally safe replacement. Consider calcium, D3, diet and animal condition together: avoid improvised extra doses.
UVA contributes to environmental perception and behaviour and cannot be replaced by vitamins or calcium. A reptile UVB source normally also emits UVA: check its declared spectrum. If the existing lighting lacks it, complete the installation with a suitable source; an ordinary white LED does not guarantee UVA and a UVA-only lamp does not provide UVB.
Humidity and ventilation
Maintain humidity at 70–80% and offer a retreat with higher humidity. Measure near hides without letting the hygrometer touch wet bedding, and also inspect substrate beneath retreats. If readings stay outside the specified values, check blocked vents and standing water before adjusting water input; recheck after the change.
Feeding
Salvator merianae is omnivorous: a varied diet includes whole prey, invertebrates and plants. Gradually increase plants with age; energy-dense food should not compensate for seasonally reduced activity.
Recommended foods
The tiers describe dietary use: rotate foods within each tier rather than treating them as an absolute nutritional score.
| Food | Dietary role | Benefits and limits | Preparation |
|---|---|---|---|
| Whole captive-bred thawed rodents | Main choices | Skeleton, organs and muscle together supply nutrients absent from meat alone; select prey size according to swallowing ability and the portion specified for the species. | Thaw completely in a refrigerator in a container separate from human food, then warm in a sealed bag in warm water. Do not microwave or refreeze. |
| Crickets and locusts | Main choices | Supply protein and encourage hunting; calcium is low relative to phosphorus, so preparation and supplementation are needed. | Use captive-bred insects and gut-load them as described below. Select suitably sized feeders, place the meal’s batch in a clean container and apply a thin calcium coating immediately before offering them. |
| Cultured earthworms, snails and varied proteins | Main choices | Provide animal-food variety; snails with swallowable shells also supply minerals. No single meat balances the plant component on its own. | Use controlled sources and small bites; meat and eggs, if used, should be well cooked and unseasoned, in rotation without replacing all variety. |
| Chicory, endive, dandelion and other edible leaves | Main choices | Supply fibre and varied minerals with lower energy density than fruit and seeds. Rotate plant species: no single leaf balances the whole diet. | Identify plants, wash and cut into manageable pieces. Avoid treated plants, unidentified ornamentals and iceberg lettuce as the only green. |
| Squash, courgette, edible flowers and varied vegetables | For rotation | Add variety, but soft vegetables should not replace all fibrous leaves. | Wash, remove hard seeds and chop; mix with leaves to discourage selective feeding. |
| Ripe fruit | For rotation | Rich in water and sugar and not a complete food; offer a small taste replacing part of the meal. | Wash and remove stones and large seeds; no syrup-preserved fruit, honey or added sugar. |
| Boneless meat and organs alone | Avoid / not a staple | Do not replace whole prey: muscle meat is calcium-poor and a liver-only diet can supply excessive vitamin A. | Do not use steak, boneless chicken or processed meats as the regular diet. |
Comparable nutritional values
Protein, fat, calcium and phosphorus are percentages of dry matter, excluding water; dry matter itself is a percentage of fresh weight. These are reference analytical values compiled in a clinical table, not guaranteed contents of your batch or a universal ranking. Age, rearing, feeding and supplementation change composition. Do not compare them directly with fresh-food percentages or already diluted prepared diets. Comparable numbers are not provided for other foods.
| Insect | Dry matter | Crude protein | Crude fat | Calcium / phosphorus | Ca:P |
|---|---|---|---|---|---|
| Adult house cricketAcheta domestica | 32% of fresh weight | 62.6% DM | 20.4% DM | 0.3 / 1% DM | 0.3:1 |
| Migratory locustLocusta migratoria | 31% of fresh weight | 67.5% DM | 14% DM | 0.1 / 0.7% DM | 0.14:1 |
DM = dry matter. Ca:P describes calcium relative to phosphorus before supplementation: a protein-rich feeder may still be calcium-poor. Offered portions remain those for this species and life stage.
Meals by age and size
| Stage and size | Frequency | Amount per meal |
|---|---|---|
| Young: about the first 6 months | Daily | Small prey and bites in one measured portion; start with a short 5-minute session and record intake. Offer chopped plants as well without removing the animal component. |
| Juveniles: about 6–24 months, still growing | Every other day | Serve one dish portion with an initial volume roughly equal to the head; include whole-prey volume in the total. Reduce bite count when increasing bite size. |
| Adults over about 2 years, during the active phase | About 2 meals weekly | Use a measured portion maintaining stable weight, starting with the head-volume method. Do not add rodents to an already full meat bowl or feed daily in response to the owner’s presence. |
Adjusting portions
To assess the portion, compare the amount and type of food eaten with growth and body condition. Weekly weighing of juveniles and monthly weighing of adults helps follow the trend. Adjust the ration gradually when growth or reserves require it; reduce it if body condition indicates excess weight or leftovers remain. Investigate unexpected weight loss or abnormal swelling rather than addressing it only with more or less food.
Preparing and offering meals
Prepare insects during the 24–48 hours before feeding: keep them in their culture container with a complete feeder diet and safe hydration. Check access to food and water and remove spoiled leftovers. Then select feeders of the specified size and prepare only the batch to be offered. This step, called gut-loading, improves prey quality; bran or potato alone do not correct deficiencies.
At feeding time the prey should be easy to swallow. As an initial guide, choose insects no wider than the space between the eyes, then adapt size to the mouth and the animal’s response. Offering them individually or in an escape-resistant dish lets you see actual intake and remove leftovers.
Thaw completely in a refrigerator in a container separate from human food, then warm in a sealed bag in warm water. Do not microwave or refreeze.
Trial amounts are a starting point for a healthy, active animal at correct temperatures: record intake and weight trend, then adjust the ration. Do not feed again merely because it continues striking at prey.
Calcium and vitamins
Immediately before feeding, lightly coat low-calcium insects with phosphorus-free calcium: they should remain visible, without clumps. Common insects often have an unfavourable calcium:phosphorus balance; rotating them alone does not correct it.
Meat alone is calcium-poor; a homemade diet needs formulation rather than guessed doses. Assess supplementation against actual foods: insects, whole prey and complete formulations are not treated the same way.
Choose one supplementation programme: plain calcium for ordinary meals and a species-appropriate multivitamin at its labelled feeding intervals. Record the product and its existing D3 and vitamin A; do not add a second dose to meals using a combined product. With measured UVB, agree the oral D3 provision; product concentrations are not interchangeable.
Daily care
First days
Keep retreats accessible and observe without opening them to look for the animal. Check climate readings from outside, offer scheduled food and record actual intake. Prepare the scales and container before weighing so the transfer stays brief; compare weight with earlier records rather than relying on appearance alone.
Cleaning
Keep animals and equipment away from kitchens and food areas, use tools dedicated to each enclosure and wash your hands with soap and running water after handling animals, food, tank water or furnishings. Quarantine new arrivals separately and agree the duration and checks with a veterinarian before introducing them to established animals.
Handling
Before a transfer, prepare an open container and an access route. Allow the animal to enter where possible; if support is necessary, support its body without gripping the tail and minimise time out of the enclosure. Stop repeated attempts to grasp it and allow withdrawal to a retreat.
Checks
Record weight, appetite and behaviour; consult a veterinarian experienced with the species if changes persist. For laboured breathing or wounds, contact them promptly without waiting for symptoms to persist.
Breeding
Sex, maturity and readiness
Confirm species, origin and sex in developed adults; large male jowls alone are no guarantee. Prepare dividable enclosures and a robust but non-obese female. Capacity for dozens of juveniles must precede pairing.
Start a record for each breeding animal with identity, origin, documented age and previous weights. Compare the weight trend with growth and body condition; delay introductions for animals still growing rapidly, losing weight or recently acquired. Use stated ages as guidance alongside these checks. If sex cannot be identified reliably, obtain assessment by qualified personnel before pairing.
Preparation and seasonal cycle
Breeding normally follows seasonal emergence. Gradually restore basking and meals and observe animals before pairing. Maintain a separation barrier operable from outside: males and females may become territorial.
Before encounters, prepare and test offspring enclosures and have first foods available. Check records for regular adult feeding and good body condition, then verify access from exposed areas to retreats. If the species protocol includes seasonal changes, adjust settings gradually and record the response. Record night-time air, surface and egg temperatures separately, noting where each is measured. Keep water available throughout preparation.
Courtship and mating
Introduce only identified, compatible adults, with another enclosure ready. Observe from a distance and end the encounter if you observe persistent pursuit, injuries or an animal unable to move away from its partner; do not forcibly separate animals during copulation. Record the date, both identities and what you actually saw: courtship, contact or mating alone does not prove fertilisation.
Before laying and the nest
Offer a large sheltered box with plant material and moist soil, deep and wide enough for nest construction and closure. Females may vigorously defend it; wait for her to leave and secure separation before collecting eggs.
Maintain a suitable laying site even without a male: females can produce unfertilised eggs. Persistent straining without laying, weakness or tissue protruding from the vent require prompt veterinary assessment. Do not wait for a predicted laying date if these signs appear. Do not squeeze the abdomen, pull eggs or give drugs to induce laying without veterinary direction.
Egg incubation
Use roomy containers with airy moist substrate and stationary eggs. Development around 60–75 days is reported, but no single temperature is assigned here because accounts differ. Do not transfer tropical Tupinambis timings, which can be much longer.
Test the system before laying with an independent probe at egg height. Use clean, labelled containers, closed but allowing air exchange, with room for eggs and hatchlings. Keep eggs in their original orientation and do not detach eggs glued to their support. The substrate should retain moisture without free water on the shell; check condensation and water loss, adding water at the edge of the substrate rather than onto eggs. Record temperature and events daily without needless opening. The stated times are approximate: do not increase heat to meet a date.
First meals and juvenile care
After yolk absorption offer small invertebrates and complete components of the species’ omnivorous diet in monitored meals. Provide shelters, UVB and shallow water; separate by size and aggression and do not feed youngsters muscle meat alone.
During the first weeks, monitor each youngster: a feeding group does not guarantee that every individual eats. Record intake, droppings and weight at regular intervals to follow growth and adapt housing and food size. Provide separate accommodation if competition prevents an individual from feeding or size differences become marked. Document repeated independent meals before transfer to another keeper.
Female recovery
After reproduction provide water and the usual balanced diet, initially in manageable portions; monitor weight, activity and return of appetite. Keep supplements and lighting consistent with the feeding guide. Avoid further introductions until the previous condition has recovered; later clutches may occur without another mating. Persistent straining, weakness or protruding tissue require veterinary attention, without squeezing the abdomen.
Equipment and example diary
Place the nest where it can be checked without dismantling the enclosure. Label containers with female identity and laying date and prepare the specified medium; for attached eggs, instead provide guards in place without detaching them. If using an incubator, install a thermostat and independent probe and test it before laying. Run offspring enclosures too and prepare scales and first food, reserving capacity for later clutches.
A consistent diary using actual dates helps follow reproduction in Salvator merianae. Start with adult identity, weight and condition, then record observed encounters, laying or birth and development conditions. After emergence record the first meal actually accepted and each youngster’s growth while continuing to follow female recovery. Over time these records help identify your lineage’s pattern without turning approximate durations into deadlines.