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Home > Spider > Brazilian Whiteknee Tarantula: Facts, Pictures, Lifespan, Behavior & Care Guide

Brazilian Whiteknee Tarantula: Facts, Pictures, Lifespan, Behavior & Care Guide

Brazilian Whiteknee Tarantula

While some of us panic and run away the second we spot a spider, others enjoy their simple nature and undeniable beauty. Tarantulas are nothing to be afraid of, and the Brazilian Whiteknee Tarantula is becoming a best-seller. They aren’t too large, and they have simple needs that make them the perfect choice for beginners or more experienced tarantula owners. Here are some informative facts and tips if you’re interested in owning one of these gentle and beautiful creatures.

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Quick Facts about Brazilian Whiteknee Tarantula

Species Name: Acanthoscurria geniculata
Family: Theraphosidae
Care Level: Moderate
Temperature: 76°F to 82°F
Temperament: Docile but skittish
Color Form: Black, white, red
Lifespan: Females- 20 years, Males- 4 years
Size: 7” – 8.5”
Diet: Insects, lizards, mice
Minimum Tank Size: 10” x 10” x 20”
Tank Set-Up: Plenty of ventilation with peat moss or Cocofiber substrate

Brazilian Whiteknee Tarantula Overview

The Brazilian Whiteknee Tarantula, also called Acanthoscurria geniculata, is a species native to Brazil’s rainforests. They get their name from the striking white patches on their legs. They are one of the most popular tarantula species in captivity and are great for all skill levels. Females reach up to 8 inches tall, with males only being an inch or two smaller. They are easy to handle but still a little skittish, though they aren’t known to bite very often.

As the Brazilian Whiteknee spiderlings grow, they become more confident. It’s as if they become aware of their size and are less likely to run away and hide as they would when they are younger. These tarantulas are aggressive eaters and become more confrontational when a meal is in front of them. They eat almost every single day unless they are molting. Regardless, Brazilian Whiteknee Tarantulas are a great place to start if this is your first time thinking about buying a tarantula. They are impressive to observe, and you may find that you want another soon after getting the first.

brazilian whiteknee tarantula
Image Credit: aappp, Shutterstock

How Much Do Brazilian Whiteknee Tarantula Cost?

The Brazilian Whiteknee Tarantula gained popularity in the 1990s and soon become one of the most sought-after tarantulas. Since then, the desire for them has remained consistent, but the prices have remained relatively cheap. Expect to pay prices anywhere from $50 to $100 dollars for a Brazilian Whiteknee Tarantula spiderling. Always try to purchase pets from a reputable breeder who makes the tarantula’s safety the top priority.

Typical Behavior & Temperament

The Brazilian Whiteknee is a New World Tarantula with urticating or stinging hairs. These tarantulas are more likely to hide than to face a fight, but they do tend to be a little nervous. They sometimes kick up some hairs while they retreat, which can be dangerous if you get them in your mouth, nose, or eyes. As long as you move slowly and with caution, they’ll soon become more comfortable with you.

Appearance & Varieties

There is a reason this tarantula gets the name Whiteknee. These large species reach up to 8.5 inches in length. They have a black body with bright white bands across each of their eight legs. They also have red abdominal hairs and velvety bodies.

Spiderlings don’t gain their adult colors very quickly, but that is part of the fun of owning a tarantula. It takes a few years, but once they have a 1-inch leg span, the spiderlings usually start to show their first signs of adult colors. Once they are a little larger, more adult coloring becomes more prominent. The spiderlings begin as small and brown and blossom into massive, striking tarantulas.

brazilian whiteknee tarantula
Image Credit: rmk2112, Shutterstock


How to Take Care of Brazilian Whiteknee Tarantula

Habitat, Tank Conditions & Setup

Brazilian Whiteknee Tarantulas are fast growers, and you’ll have to keep up with their basic requirements. They require certain sized enclosures, bedding, and heat sources that ensure they live comfortably.


For young spiderlings, using plastic cups or tubes as housing is acceptable. They won’t require a larger house until they have a ⅘-inch leg span. Once they are this size, you can move them to an adult enclosure. A 10 to 15-gallon tank is the ideal size for an adult Brazilian Whiteknee. You don’t want too much height in the tank or they may fall and hurt themselves.


Most adult tarantulas like to have a hide they can retreat to, but spiderlings prefer to burrow themselves under the tank’s substrate. Peat moss, potting soil, vermiculite, and Cocofiber are good substrate choices for this species. Try to choose organic or chemical-free products and refrain from using pebble, rocks, wood chips, or sand because they could injure the tarantula.

Temperature and Humidity

Room temperature is fine for most tarantulas, but these once thrive when the temperatures remain between 76°F and 82°F. If you live in an area with colder winters, heat mats are okay to use as long as you don’t put them directly under or on the sides of the enclosures. Tarantulas don’t feel heat and could cook alive. Instead, put the mat close by and use a thermostat inside the tank to ensure it is at the optimal temperature.

Because these tarantulas come from the rainforests of Brazil, they enjoy a really humid environment. Keep humidity levels around 65% to 75%. Spraying water into the tank once or twice a week usually suffices.

brazilian whiteknee tarantula
Image By: Dave Denby Photography, Shutterstock

Cleaning and Lighting

Tarantulas do not require any light and do not ever use heating lamps. Most tarantula tanks don’t require cleaning unless you see mold or smell funny odors coming from the enclosure.

Do Brazilian Whiteknee Tarantula Get Along with Other Pets?

If you have other pets already in the house, you might want to refrain from bringing home a tarantula. Tarantulas aren’t exactly known for getting along well with other animals. A bite probably won’t hurt your cat or dog too bad, but they are nervous, and you wouldn’t want to make either one uncomfortable.

As far as keeping tarantulas with other spiders, we wouldn’t recommend it. Always keep your tarantulas in separate enclosures, so they have their own territory. If you put them together, they’ll eventually confront one another, and the last thing you want is for one of them to get wounded.

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What to Feed Your Brazilian Whiteknee Tarantula

Adult Brazilian Whiteknee spiders eat every 5 to 10 days as spiderlings and less often as they mature. Adult tarantulas might eat once every 6 to 14 days. Adults enjoy eating cricket, roaches, or mealworms, though they have been known to eat lizards and mice as well. Spiderlings under ¾ inches only eat food that is small enough for them to overpower. Pinhead crickets, pinhead roaches, and flightless fruit flies are good choices for the smaller tarantulas.

Do not feed your tarantulas wild-caught food because they might contain parasites or pesticides, both of which could be fatal to them. Remove the food waste once they are don’t to prevent mold, mites, and mildew from making their way inside. It is safe to remove uneaten prey after 3 to 12 hours of being left untouched.

Give spiders a shallow dish to drink water from. Rinse out the bowl every time you go to refill it. Keep it in the corner of the enclosure.

brazilian whiteknee tarantula
Image By: aappp, Shutterstock

Keeping Your Brazilian Whiteknee Tarantula Healthy

Keeping a Brazilian Whiteknee Tarantula healthy is a matter of giving them their basic requirements. Make sure that their enclosure is always clean and free of mold and pests. Change out the substrate about once a month or more if you notice any strange smells coming from inside. Keep the tank moist and have a thermostat, so you always know what the temperature is. Give them a place to retreat and feel safe, and feed them regularly, especially while maturing into adults. Tarantulas might act strangely after a molt, so don’t be too worried about them during this time. If they are acting out of character two days after a molt, reassess to make sure they are getting everything they need out of their enclosure.


Female Brazilian Whiteknee tarantulas are a little more defensive around the males than when they’re alone, but the mating process goes relatively smooth compared to other Brazilian tarantula types.

Mate the tarantulas 4 to 6 weeks after a molt and make sure the female is well fed but not obese before introducing her to the male. Use long tweezers to separate the male and female immediately after they finish mating.

Females enjoy burrowing themselves after they finish mating, so don’t stop her from doing this and preparing for the cocooning process. After three months pass, drop the humidity to around 60% to 70%. She starts to make her cocoon 4 to 7 months after the mating took place, and it contains anywhere from 600 to 1,000 fertilized eggs.

Are Brazilian Whiteknee Tarantula Suitable for You?

The Brazilian Whiteknee Tarantula is a fascinating creature. Some people don’t describe them as the most interesting species to look at, but their force when they feed and gentle nature makes them a great choice for tarantula lovers regardless of their experience with them. As long as you can appreciate their subtle yet striking beauty and remain calm when working with them, you shouldn’t have too many issues when raising these tarantulas.


Final Thoughts

Don’t fret if you don’t have any experience with tarantulas. These aren’t one’s that you’ll want to handle without gloves because of their pokey hairs, but they are great if you want to learn the basic about tarantula care and observe the way they eat, burrow, and molt. The Brazilian Whiteknee tarantula is an impressive spider and one that most people enjoy having in their collection.

Featured Image Credit: Milan Zygmunt, Shutterstock

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