Mexican Red Rump as Pets: Lifespan, Size and Care Info

What You Need to Know About Mexican Red Rump as Pets

The Mexican red rump is an exciting spider famed for its fascinating coloration and docile nature. The red rump tarantula sports a dark brown body and reddish-orange leg joints. These legs are equipped enough to detect tastes and vibrations. This helps the red knee navigate around and also catch prey for food. For their docile nature, Mexican red-knee tarantulas are frequently paraded in Hollywood films.

The Mexican red rump can grow up to 6 inches and can live up to 20 or more years. They are venomous but generally docile. These spiders only show aggression when threatened and would display fangs or shoot hairs at the supposed predator. Nonetheless, this is not very harmful to humans. In sharp contrast to other spiders, Mexican red knees dig into the ground instead of building a home above the ground with webs.  

Mexican red knee tarantulas are exotic pets, and they require significant knowledge to raise. You need to know the appropriate conditions to rear your red rump like getting the befitting size of the terrarium, the right temperature, heating, and lighting conditions. You also need to know how these spiders molt and breed. These are the valuable pieces of information we will explore in this post.  

How Long Do Mexican Red Rump Tarantulas Live?

Mexican red knee tarantulas live pretty long. The female red knee particularly is long-lived, with a lifespan that stretches as long as 30 years. The male red rumps live much shorter around 5-10 years and are known to die a year after maturity. In some cases, the males get eaten up by the female.

Mexican Red Rump Size

Unlike other animals where the male outgrows the female, the female Mexican red rumps are bigger than the male. While the male can grow up to 5 inches, the female comes larger, growing up to 6 inches. This increased size allows the female red knees to prey on the male or generally molest it.

Mexican Red Rump Color

Adult Mexican red knees are famous for the red hairs adorning their abdomen. This color is replicated across male and female red kneed only that for females, the red color on the belly is brighter and appears more prominent due to its larger size. For the younger spiderlings, they tend to have this brown color.

Are Mexican Red Rump Spiders Poisonous?

Well, it is worthy to note that Mexican red rumps are venomous. Yet this doesn’t necessarily mean that these red rumps are poisonous to humans. It is rare for these spiders to attack and bite humans.

Even when they do – as in those rare cases where they feel stressed – these bites are not fatal. When a Mexican red rump bites you, you won’t fee more pain than you would when a bee stings you.   

Mexican red rumps find this venom very helpful when they prey on small lizards, frogs, mice, and insects. The red knee boasts two hollow fangs.

These are used for injecting the venom into the prey. This venom is produced in the red knee’s poison glands. These fangs have holes for dissemination. This causes paralysis of the prey, making it less mobile and aiding digestion. The red knee tarantula holds the victim with its front limbs for the injection of the venom.

Mexican Red Rump Molting

Mexican red knee tarantulas undergo molting too. When the red knee has grown enough, it becomes necessary for the red knee to change the skin under its exoskeleton. This is sort of the spider breaking of its previous exoskeleton – splitting it and wriggling out.

You will notice the new exoskeleton when the red knee tarantula molts. This new exoskeleton is usually soft and will harden over time. Within this time, your red knee could struggle to eat, being that its fangs and skin would be too tender.  

This is the molting process, and if you have a red knee, you will notice than within this molting interval, the red knee suffers a reduced appetite and also a decrease in activity level. You would see a sluggish demeanor in the spider with an increased tendency to lack on the back.

Typically for the first four months, spiderlings undergo molting biweekly. After this period, the frequency of molting reduces notably. For males, they will not molt after attaining their sexual prime (or maturity) when at 4 or 5 years. Females may only stop molting about 7 months after they attain sexual maturity. Mexican red-knee tarantulas mate don’t waste time, molting immediately after the male matures.

Are Red Rump Tarantulas Aggressive?

Red knee tarantulas are not aggressive; rather they are very docile. However, tarantulas may show a bit of aggression towards you when they feel threatened. In such cases, you could see the red knee parading its fangs via raising its front legs. This is expected to scare the intruder off.

Possibly, this might not work, prompting the red knee to resort to another defense mechanism. This is by kicking the hair on its abdomen at you. These are the urticating hairs. Thus mirrors the defense mechanism of porcupines shooting quills from its body. These hairs can irritate the eye or skin of the intruder as they are usually furnished with a hook at its end.

 These eyes, while they may not do significant damage to your skin, can penetrate your eyes, which can end up devastating. The way you handle a red knee tarantula determines to a large extent the way it would interpret you: as a friend or prey.

Care of Mexican Red Rump

Temperament of Mexican Red Rump

Red knee tarantulas are not very sociable beings. They fare better when they live in isolation. These spiders have a knack for burrowing into the ground, digging up solitary holes for shelter. This is unsurprising, given that red knees tarantulas are fossorial species.

In a notable deviation from the general culture of spiders, red knee tarantulas deploy webs in holding their eggs rather than in trapping prey. These holes can have a depth of 18 feet. Female red knees habitually lay eggs in these burrows and leave only to come back to these holes upon the hatching of the spider-lings.

The urticating hairs it kicks out in defense mode can only cause skin irritation (so long the hairs don’t get into your eyes), which would last a few hours, although there are cases where the irritations can last for more than 24 hours. These irritations can be allergic reactions in the form of itching, rash, or even inflammation.

Terrarium size

For one Mexican red knee, a tank of 5-10 gallons would do. This is what we regularly advise: make sure the width of your terrarium should be at least 2-3 times of your red knee’s leg span. As for the height, the tank should measure up to the length of the red knee’s leg span if it stands on its end.

Now, bear in mind that these spiders love hanging out on the top of the tank. It would be great if your tank has a side opening to prevent scenarios of the red knee rump falling – especially when servicing is needed. This is why the tank should be escape-proof.

Food & Water

The standard diet of red-knee tarantulas revolves around insects like cockroach and locusts, as well as on live crickets. You can readily fetch big bugs from your yard. In all, avoid feeding your red-knee rump with plants that have a significant composition of pesticides. This could end poisonous for your spider.

To spruce up the protein content of the tarantula diet, you can bring in some small lizards or even a mouse. However, this comes with the added need of cleaning off the remains to maintain high hygienic conditions in the tank.

Mexican red-knee rumps could be stressed with just the presence of uneaten insects when they have eaten to their fill. It, therefore, makes sense to religiously take off these insects once your spider has fed fully. Tarantulas are not really big eaters. They can survive with a diet of just 1-2 meals per day.

You also need a water dish in the terrarium. The water dish should be shallow. Ensure that the water is fresh to keep the red-knee tarantulas healthy. If you can, ensure to change the water at least once every day.

Yes, you can regulate the appetite of your tarantula. When they mature, you can feed it with one big cricket or cockroach every week. However, they eat more when younger and would need at least 2 cockroaches or crickets per week.


If you want to rear a Mexican red-knee tarantula, then it is essential to aim for temperature consistency in their terrariums. Strive to keep the temperature range perpetually at 75-80 degrees Fahrenheit. This is achievable when you equip the underneath of one portion of the terrarium with a heat mat.


If you are raising your tarantula in a North American climate, you should complement the heat from the heat mat. Heat mats are cheap, but they would struggle to give your tank all the heating it needs, especially when the winter comes in with all its freezing intensity.

Polystyrene tile can work excellently as a heat reflector when located between the cage and the tile. This would help transmit a sufficient quantity of heat into the terrarium, making it for comfy for your tarantula in extremely cold weather.

Also, note that your terrarium can get excessively hot, even threatening the life of your red-knee tarantula. This explains why you need an area without heating for the tarantula to let off heat when the temperature of the terrarium is unhealthily high.


Your red rump tarantula needs optimal humidity to survive. If the tank is too dry, your red-knee rump could end up not drinking from the water dish. In such scenarios, it would just hover around the water bowl.

Humidity levels of 60-70% are perfect for your spider. As explained, water evaporating from the water dish can help keep the tank humid. If your tank gets too humid, you will notice your spider frequenting the extremes of the tank as if trying to hide away.

Leaving fresh water in the water dish may not do if you are raising the spider in tropical regions. In such cases, you would need to spray the terrarium with water frequently to enhance the humidity.

This shouldn’t be difficult. You can fill lukewarm water into a houseplant spray gun and spray it around the terrarium. Make sure you don’t directly spray the tarantula when you do so.


While spiders don’t typically enjoy direct light, Mexican red-knee rumps have a curious habit of basking in light. Bearing this in mind, you may need to procure a basking destination for your tarantula. You should be mindful of the heat quota this lighting contributes to the tank.

The lighting shouldn’t be too daring. Set it in such a way that the interior of the terrarium is only mildly lighted. Most times, we recommend that you use LED lighting. If possible, get the type of LED lighting whose intensity of brightness can be regulated in accordance with the comfort of your tarantula.

If you can’t get LED lighting with controllable brightness, you can get a desk lamp for your terrarium. However, position it such that it beams down on the terrarium. Nevertheless, you can do without lighting. It all boils down to what you want.


Mexican red rump tarantulas are significantly sexually active. Typically, the male and the female mate within the period of early September to late October. This is common with all tarantulas. 

This is how it works. Following months of maturity, the male red rump will drop a substantial amount of sperm into its webbing ball.

After depositing the sperm in this ball, it takes it along with it via its pedipalps, transversing about looking for a female to mate. Within this period, the female red-knee tarantula waits patiently for the male. Most times, the female would attract the male red rump with a dance serving as a cultural mating call.

The male approaches the hide of the female cautiously. To attract the female out of its hide, the male would vibrate its legs, tapping it distinctly into the ground. Upon the female emerging, the male would push at the female, getting her in an upright posture.

This is to enable the male to access the epigyne of the female rump easily. This way, it can insert its sperm via its pedipalps. After this, the male disengages from the female red rump.

Now, the female red rump is quite antagonistic despite its efforts to attract the male for mating. Immediately, the male drops its sperm into the female red-rump, the mood changes, and the female red-rump could attempt to eat up the male. Therefore, the male would make haste to escape at once after mating. Isn’t this intriguing?

If the mating was successful, the female red rump would produce an eggs sac in about 14 days from the mating time. These eggs and the sperms are stored in its body till Spring. Females can lay up to 200 eggs (or even 400 eggs). For fertilization to occur, the female red rump covers the eggs with the sperm, which would be sticky. Fertilization doesn’t take more than minutes.

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