Let us introduce you to our Mexican red-knee tarantula, Xena.
FACTS ABOUT XENA
Xena is a five-year-old female, Mexican red-knee tarantula, and has called JMDC her home for three years. She gets her name from the 1990’s television series Xena: Warrior Princess. However, Xena, the tarantula, is not nearly as fierce as her namesake.
DOCILE YET VENOMOUS
Xena is, in fact, very docile. Of the 900 tarantula species globally, the Mexican red-knee tarantula is one of the most docile. While the Mexican red-knee tarantula is venomous, it rarely bites. And if it were to bite a human, the pain from the venom has been compared to that of a bee sting, causing mild discomfort unless the individual has an allergic reaction to the bite.
More than likely, the tarantula will defend itself by ejecting urticating hairs from its abdomen and legs if it thinks it is in danger. The hairs will cause a stinging or prickling sensation. These barbed and mildly toxic hairs act as a defense mechanism as they embed into a predator’s skin or eyes, causing discomfort and irritation.
In humans, the hair can also cause an allergic skin reaction resulting in inflammation, rash, and itching. While this is not serious, the reaction can last for several hours or days. So despite her docile nature and mild venom, great care is always taken when handling Xena.
HOW MANY SPECIES ARE THERE
There are two different species of Mexican red-knee tarantulas. One is the Brachypelma hamorii, and the second is the Brachypelma smithi. Both species are native to Mexico, and both have a defining similarity: orange-red “knees” that contrast with their dark body color. Although scientists have pointed out slight differences in color and shape between the two species, these differences are subtle, and both species are referred to as red-knee tarantulas.
MORE FACTS ABOUT XENA
Xena belongs to the species Brachypelma smithi. She is recognized by those distinctive red-orange patches on the joints (knees) of her legs.
THE TARANTULA’S BODY
As do all spiders, Xena has four pairs of legs attached to her carapace (the hard upper shell). Like all Mexican red-knee tarantulas, she is quite talented and can hold her prey with her first two legs while walking with her other legs. Each foot has two claws, enabling Xena to climb slippery surfaces. An adult Mexican red-knee tarantula will grow to have a leg span of five to six inches.
Xena has two pairs of spinnerets on the posterior (back) side of the abdomen.
What is a spinneret? Glad you asked.
Spinnerets are flexible, tube-like structures from which the spider exudes its silk. And speaking of their silk webs, tarantulas don’t usually create webs to catch prey like other spiders. Don’t get me wrong, they can use their webbing in the hunting process, as you’ll learn later, but they also use their web for structural support, more comfortable footing, and event molting mats.
Yes, Xena and all Mexican red-knee tarantulas have eight eyes located around their head to see both forward and backward. Shockingly, however, their vision is relatively poor. For that reason, they use the hair on their legs to sense vibrations.
Taste, smell, and feel
Xena’s ability to taste, smell, and feel is due to her palps, a pair of elongated segmented appendages on the end of her legs nearest her mouth.
Mexican red-knee tarantula’s grow very slowly, molting every two weeks for the first four months of life, and then less frequently as they age. Females, like Xena, will infrequently continue to molt after reaching adulthood.
So what is molting? Molting is a process that removes external parasites and provides new undamaged sensory and protective hairs.
Females, like Xena, can live between twenty to twenty-five years in captivity.
As their name implies, Mexican red-knee tarantulas are native to Mexico, primarily along the central Pacific coast. They live in dry areas with very little vegetation, such as in scrublands, deserts, or dry thorn forests.
In their natural habitat, the Mexican red-knee tarantula lives in a burrow in rocky areas, usually found at the base of thorny vegetation like cactus. Burrows will have one entrance that is a little wider than the tarantula itself. A carpet of web extends from the burrow out of the opening and is usually covered or coated in a substrate. These large spiders will use their web to catch prey as it walks in front of the shelter.
Xena is a carnivore. She eats a variety of insects, along with small frogs, rodents, and reptiles. Once these tarantulas catch their prey, they hold it between their front legs and use their two hollow fangs to inject venom into their capture. As the toxin enters their catch, the poison liquefies their prey’s body, and eventually, the spider consumes the prey by drinking the juices. After a large meal, the tarantula can go up to a month without food. However, here at JMDC, there is no need for Xena to go so long between meals. We feed her a meal of crickets every few days.
Due to their docile nature and beautiful colors, Mexican red-knee tarantulas have become very popular in the pet trade. Unfortunately, their popularity has resulted in the species being commercially exploited within their natural habitat over the years.
Today Mexican red-knee tarantulas are rarely found in the wild and are considered “near threatened” by the International Union for Conservation of Nature (IUCN). It is now illegal to catch and sell wild Mexican red-knee tarantulas. Those sold in the pet industry must be bred in captivity.
BRED IN CAPTIVITY
When bred in captivity, Mexican red-knee tarantulas have become one of the most popular arachnids used in movies because of their bright colors and docile nature. They are slow-moving and can be handled without causing the spider undue stress.
However, directors have learned that spider actors, like human actors, can be temperamental, requiring patience from both the spider handler and the director to get the perfect shot.
A fun example of this occurred during the filming of the 1981 blockbuster Raiders of the Lost Ark starring Harrison Ford as the infamous Indiana Jones.
Indy and his companion entered a cave looking for a hidden artifact in one of the earlier scenes. Inside the cave, Indiana Jones’ companion stops to remove a couple of large spiders crawling on Indy’s back. Do you remember that scene?
Indiana then checked his companion’s back, which had dozens of large Mexican red-knee tarantulas crawling over his jacket.
REFUSING TO LISTEN TO THE DIRECTOR
Director Steven Spielberg wanted the spiders to crawl all over the actor’s back, but at first, they remained perfectly still, refusing to move. Frustrated, the director had to figure out why the hairy actors refused to move. Finally, the crew realized that the spiders were all males, and once they introduced a female tarantula in the scene, the males became active, giving Spielberg the shot he had planned.
XENA MAY NOT BE FAMOUS
While our Xena is not a warrior princess or a famous spider actor, she is an interesting member of JMDC’s Critter Corner. She enjoys being held, and even the occasional tummy tickle. Xena, as with all of our Critters, is available for sponsorship.