Mexican Red-Knee Tarantulas

a close up of a Mexican Red-Knee Tarantula

Are you considering getting a pet, but don’t know where to start? Mexican Red-Knee Tarantulas might be the perfect pet for you! These beautiful and unique spiders are becoming increasingly popular as family pets.

Mexican Red-Knee Tarantulas, also known as Brachypelma smithi, are native to Mexico and Central America. They have a distinctive black body with bright red or orange markings on their legs, hence the name. They’re a medium-sized tarantula, reaching up to 4 inches in length.

Mexican Red-Knee Tarantulas are native to the central Pacific coast of Mexico. They’re not venomous, and are harmless to humans. Mexican Red-Knees are large spiders, and have an average length of a little over 6 inches. They are also very beautiful, and are sometimes used as decorative items in art.

Mexican Red-Knee Tarantulas are very docile and gentle insects, and are usually only aggressive towards other spiders or their food. They are very territorial, and will defend their home.

These tarantulas make great pets for first time owners because they are relatively easy to care for and don’t require a lot of space. They can live in a 10-15 gallon tank with plenty of substrate and a few hiding places. They also don’t need to be fed very often, only once or twice a week.

Mexican Red-Knees are very docile and calm, and will make great pets for children. They are also very easy to care for and won’t require much maintenance. They don’t require much food, and will eat insects and smaller living food. Because they are native to Mexico, they will thrive in warm weather.

Mexican Red-Knee Tarantulas are known for the red on their knees. You can find them in a number of different pet stores near you. Red-Knees are one of the more expensive Tarantulas, expect one to cost between $80 and $150.

When it comes to handling your Mexican Red-Knee Tarantula, it is important to remember that they are still wild animals and can be skittish. It is best to handle them with care and respect, using slow movements so as not to startle them.

Many people are hesitant to get a tarantula as a pet because they think they will be difficult to care for, but that is not the case with Mexican Red-Knee Tarantulas. They are actually quite docile and can make great family pets. I have had my own Mexican Red-Knee Tarantula for over five years now and she has been a joy to have around.

In conclusion, Mexican Red-Knee Tarantulas are a great pet for first time owners. They are relatively easy to care for and don’t require a lot of space or food. Plus, they can make great family pets if handled with care and respect. If you’re looking for an interesting and unique pet, then the Mexican Red-Knee Tarantula might be the perfect choice for you!

Mexican Red-Knee Tarantula Information

  • Average Length: 6.5 inches
  • Average Weight: 0.5 ounces
  • Skin Appearance: Hairy with striped color patterns
  • Skin Colors: Black, Red, Orange and Tan 
  • Grooming Needs: Low
  • Shedding: Several times before adulthood
  • Sensitive to Touch: No
  • Biting Tendency: No
  • Tolerance to Heat and Cold: No 
  • Good Pet: Yes
  • Safe with Children: Yes
  • Good with Other Pets: No
  • Suitable to live in an Apartment: Yes
  • Good for Less Experienced Pet Owners: Yes
  • Weight Gain: Normal
  • Health Concerns: Abdominal Fractures, Dehydration, and Molting Problems
  • Average Life Span: Females – 25 years, Males – 6 years

Mexican Red-Knee Tarantulas are found on the Pacific Coast of Mexico. They live along the drier scrublands, deciduous forests, dry thorn forests and deserts.

Physical Appearance of Mexican Red-Knee Tarantulas

a Mexican Red-Knee Tarantula on the bottom of their enclosure

Mexican Red-Knee Tarantula is made up of two different tarantula species – Brachypelma hamorii and Brachypema smithi. Both species have bright red knees that contrast with their body, and that is how they get their name.

They have a black body with brown hair and a red ring around the edge of their body (thorax). Their carapace (the part that joins their head and body) is beige with a black square in the middle. Their legs have black stripes with bands of orange, red or tan.

They can grow up to 6.5 inches long and are one of the largest Tarantula species. Females are slightly longer than males, but males have longer legs.

These Tarantula species have hairs on their back legs called ‘urticating hairs.’ They can shed these hairs when threatened by a predator. The hair is not venomous but it can cause mild skin and eye irritations in people.

Temperament of Mexican Red-Knee Tarantulas

Mexican Red-knee Tarantulas are one of the most docile and easy to care tarantula species. Their peaceful temperament makes them popular pets. While most tarantula species should not be handled, because Mexican Red-knee Tarantulas are more even tempered they can be handled without any issues. They usually don’t bite their owners but may shed urticating hairs when they feel threatened. The hair causes discomfort and is the primary defense of western Tarantulas.

While many Tarantula species spend most of their time in hiding, the Mexican Red-Knees are more active. They don’t mind being out in the open and letting their owners watch them.

Mexican Red-knee Tarantulas are great pets for beginners.

Their Compatibility with Children

a Mexican Red-Knee Tarantula looking for food under some wood

While these Tarantulas don’t get aggressive, children still shouldn’t handle them. The skin irritation that can be caused by the Tarantula’s hair can irritate childrens skin or eyes. Children need to wash their hands if they interact with your Tarantula or their cage. Washing their hands should remove the urticating hair that children could have come in contact with.

Living Space for Mexican Red-Knee Tarantulas

Mexican Red-Knee Tarantulas should be kept alone. A small cage or glass tank are good enclosure options. Their living space should be well-ventilated and secured to keep them from escaping. A secure lid on top of their tank should keep them from escaping. 

Cage Size

The enclosures length and width should be 2 to 3 times their leg length. They are ground dwelling species and poor climbers. The height of the cage is not as important as the floor space is for Red-Knee Tarantulas.

A cage or tank with 12 inches length and width or a 20-gallon tank should be a good fit for an adult Tarantula.


Mexican Red-Knee Tarantulas need a substrate that will let them borrow. A 4 inch thick and loosely packed substrate mix of peat moss, soil and vermiculite will be great for them to burrow in.

a Mexican Red-Knee Tarantula walking over a piece of wood


Create a few hiding spots by adding a flowerpot or curved pieces of cork. These hides should be large enough to let your Tarantulas completely hide. 

A few plants can be added to mimic their natural environment.

Water Source

A shallow water bowl should be placed inside their tank. While Mexican Red-Knee Tarantulas don’t drink often, the water in the bowl should still be replaced every day. 

Best Climate for Mexican Red-Knee Tarantulas

Create a warm and hot area inside your Tarantula’s living space. Having different temperature areas will let your Tarantula cool down if their tank gets too hot for them.


Mexican Red-Knee Tarantulas need a temperature kept between 75°F and 80°F. If your home’s temperature is in this range then additional heating equipment won’t be needed. Otherwise using an under tank reptile heat mat under one third of their enclosure should keep the temperature in this range.


a close up of a Mexican Red-Knee Tarantula

The humidity should be kept between 60 and 70 percent. The water bowl kept inside their tank should help keep the humidity higher. Because they need a high humidity its likely that they’ll need their tank misted a couple of times during the day.


Tarantulas are nocturnal and don’t need any lighting equipment. Their cage should be kept at a location that doesn’t get direct sunlight because it can overheat them. If you want to add lights to see your spider while they’re active we suggest using some LED lights on a dim setting.

Because these spiders are nocturnal they don’t need UV light.

The Attention a Mexican Red-Knee Tarantulas Needs

Tarantulas in general don’t need a lot of attention. Most of their attention needs have to do with keeping the temperature and humidity high enough, and keeping their cage clean. A few thermometers and hygrometers in their enclosure will let you check the climate in your Tarantula’s tank.

While other Tarantulas should not be handled, because of their docile temperament the Red-Knee can be handled regularly.

Health Issues

Common health issues in Tarantulas are:

Abdominal Fractures

If your Tarantula falls, there is a chance that they could rupture their abdomen. If their abdomen has ruptured you’ll see a clear or yellow looking fluid leaking out of them. Essentially this is them bleeding.

There are a number of tricks that Tarantula owners will use to try to stop the bleeding. Flour and cornstarch are very popular as is super glue. Super glue dries fast and will help stop the external bleeding. Depending on how bad the internal injuries are, it might not matter though.

Make sure that your Tarantula has access to all the water they need, and depending on how they appear, you may want to wait to feed them. If they live beyond a few days they should recover. Just remember this is why it’s best not to handle Tarantulas.


Tarantulas need water to survive, but they don’t need to drink water everyday. Spiders can live for weeks, possibly months without food and for three weeks without water. 

Tarantula dehydration symptoms you’ll see: 

  • They’ll be lethargic 
  • Their body will look shriveled or shrunken 
  • Their body may look wrinkled.

A mildly dehydrated Tarantula will usually have a shrunken abdomen and be inactive. A severely dehydrated Tarantula will usually have some degree of leg curling underneath their body.

The treatment for dehydration is water. It’s best to keep a water dish in their enclosure to keep your Tarantula hydrated. A mildly dehydrated tarantula will usually recover within 24 hours, but if they’re very dehydrated a couple of days might be needed.

If you think that your Tarantula isn’t rehydrating contact your vet immediately.

Molting Problems

For insects that molt, molting is the most dangerous time for them. If the conditions are not right during the molting process they could die from being trapped in their old body.

Signs your Tarantula is having problems molting:

  • Stuck in the old carapace
  • One or more legs fail to release from the carapace

Humidity is very important to molting. If you know that your Tarantula is about to molt it’s always a good idea to raise the humidity level within their enclosure. If your Tarantula is dehydrated it can also make molting difficult.

If you notice that your Tarantula is stuck and unable to free themselves from their old carapace there are a few options. With a wet paint brush or Q-tip you can try to help moisten the area where the problem is.

If they have a leg that they can’t free and water isn’t helping get it out you can try to pull the old carapace off with tweezers. Be careful and don’t try to pull too hard because pulling too hard could damage or remove part of the leg. If the leg becomes damaged and doesn’t fall off on its own in a few days it should be removed. If left in place it’s very likely to cause problems in the next molt.

Oral Nematodes

Usually by the time nematodes are noticed it’ll be too late to save your Tarantula. By the time they’re coming out of your Tarantula’s mouth, they’ve already done a lot of damage inside of their digestive system.

Still some people have reported success using treatments to kill the nematodes, and a veterinarian can remove the nematodes while a Tarantula is under anesthesia. If you think your Tarantula has nematodes it’s very important to talk to your vet as soon as possible. Tarantulas that are born in captivity are less likely to be affected by this disease.

Tarantulas don’t need to eat very often. Because the nematodes don’t kill Tarantulas directly, death by starvation can take months.

Tarantula Oral Nematode symptoms you’ll see:

  • White material around mouth parts
  • Decreased or non-existent appetite

It’s important to remember that Tarantulas can fast for weeks at a time and this is normal. If you start to see anything white appearing near their mouth you’ll want to immediately contact your vet. Of the 2 medications that have reportedly been used to kill the nematodes, Cefotaxime will require a prescription from your vet. Pyrantel should be available over the counter, but used alone it doesn’t seem very effective at killing nematodes.

General Mexican Red-Knee Tarantulas Care

Tarantulas don’t need a lot of care. Spot clean their enclosure every other day. The entire enclosure should be cleaned thoroughly and the bedding changed about once every six months.

Feeding A Mexican Red-Knee Tarantula

Mexican Red-Knee Tarantulas should be fed insects like crickets, cockroaches, grasshoppers and larger bugs. They like to eat live crickets and depending on where you live, this may require you to raise and feed live insects. Before feeding them wild caught insects make sure the insects are pesticide-free.

Tarantulas will not eat insects if they are full and might get stressed watching insects inside of their enclosure. Remove any uneaten insects if your spider doesn’t have any interest in eating them.

Occasionally pinky mice can be fed to adult Tarantulas because they are a good source of protein. It’s a good idea not to feed them anything bigger than they are because it’s too much for them.

Mexican Red-Knee Tarantulas should be fed about twice a week. They may not eat anything when they are molting. During molting they are weak and feeding live insects could harm your Tarantulas. If you see that they are molting, or about to start its a good idea to wait a few days before trying to feed them.

Related Questions:

When do Mexican Red-Knee Tarantulas Molt?

Mexican Red-Knee Tarantulas can molt up to 20 times in a span of 4 years. This is when they become adults. After becoming adults they’ll never molt again.

Which is Better For My Family a Male or Female Red-Knee Tarantula?

Mexican Red-Knee Tarantulas have one of the longest life spans among all Tarantula species. Males only live for up to 6 years but females can live up to 30 years. Male Mexican Red-Knee Tarantulas usually die soon after reaching sexual maturity. If you want a longer living pet then a female Mexican Red-Knee is a great choice.