Mastering the Care of the Colombian Lesser Black Tarantula
Introduction
If you are looking for a spider that "absorbs the cosmos," look no further than the Xenesthis immanis, commonly known as the Colombian Lesser Black Tarantula. While the name might suggest a simple black spider, the reality is far more spectacular. This species is famous for its incredible "starburst" pattern—a shimmering explosion of purple and pink on its carapace that glows against its velvety black legs. Native to the humid rainforests of Colombia, it is often considered one of the most beautiful large terrestrial spiders in the world. For the tarantula keeper, the X. immanis is a prestigious display animal that combines high-fashion aesthetics with a massive, prehistoric presence.
Size, Growth, and Longevity
The "Lesser Black" is only "lesser" in name; in size, it is a true heavyweight. Adult females can reach an impressive diagonal leg span of 19cm to 22cm (7 to 9 inches), putting them in the same size category as some birdeaters. They are known for a medium-to-fast growth rate, meaning they don't stay small for long. A well-fed spiderling can reach a substantial juvenile size within its first year. Longevity is a major plus for this new-world giant; while males live for about 3 to 4 years, females can thrive for 12 to 15 years or more. In the hobby, they are often seen as a "centerpiece" spider because they grow quickly enough to satisfy the impatient keeper while living long enough to be a staple of the collection.
Temperament and Suitability
The Xenesthis immanis is a fascinating study in new world temperament. While they are generally not aggressive, they are notoriously skittish and bolty, especially as juveniles. They possess urticating hairs and will not hesitate to flick them if they feel cornered. One of the most interesting traits of this species is its confidence; unlike many large spiders that hide away, an adult X. immanis is often quite visible, sitting out in the open to showcase its vibrant carapace.
Because of their speed, size, and specific humidity requirements, this species is best suited for intermediate keepers. They aren't as "moody" as some old-world spiders, but their "teleporting" speed during rehousing can be a challenge for a complete beginner. For those who have mastered basic terrestrial care and want to move into high-end, large-scale spiders, this is the perfect next step.
Enclosure Setup
As a large terrestrial, the X. immanis needs a spacious enclosure with plenty of floor room. For an adult, a minimum of 45cm to 50cm in length is recommended. They occasionally dig, so provide at least 15cm of deep, moisture retaining substrate. In their natural habitat, they are known for a unique mutualistic relationship with small frogs (which protect the spider's eggs from ants), highlighting their need for a complex, naturalistic environment.
Humidity is the most critical factor for this species. It should be kept high—around 75% to 80%. This is best managed by keeping the lower layers of substrate damp while providing excellent ventilation to prevent stagnant air. They are legendary eaters and will tackle almost any insect prey, from large crickets to dubia roaches, with a very enthusiastic feeding response. A large, shallow water dish is a must, as these giants can dehydrate quickly if the environment becomes too arid.
Conclusion
The Xenesthis immanis (Colombian Lesser Black) is a crown jewel for any tarantula enthusiast. Its blend of massive size, rapid growth, and that unmistakable purple starburst carapace makes it one of the most rewarding new world spiders to keep. While it requires a bit more attention to humidity than your average desert species, the visual payoff of seeing a 20cm iridescent giant sitting at the mouth of its burrow is worth every bit of effort.
