Colombian Lesserblack Tarantula

Xenesthis immanis Care Guide

Colombian Lesserblack Tarantula

Revision Date: March 2025

Introduction

Xenesthis immanis, commonly known as the Colombian Lesserblack Tarantula, is a large, tropical New World species renowned for its vibrant pink and purple hues, striking leg striping, and impressive size. Native to Colombia and Venezuela, this species is a terrestrial opportunistic burrower, preferring humid environments with ample space to roam and burrow. With a fast growth rate, aggressive feeding response, and bold temperament, this species is best suited for experienced keepers who can meet its moisture and space requirements.

One of the most visually stunning tarantulas in the hobby, X. immanis can reach an impressive leg span of up to 9 inches (23 cm), making it one of the largest species within the Theraphosidae family. While not excessively defensive, this species can be skittish and fast, making it more suitable as a display species rather than one for handling.

Quick Species Snapshot

• Scientific Name: Xenesthis immanis

• Common Names: Colombian Lesserblack Tarantula

• Type: Terrestrial, Opportunistic Burrower

• Category: New World

• Native Range: Colombia, Venezuela

• Size: Up to 9” (23 cm) DLS

• Growth Rate: Fast

• Life Expectancy: Females ~15–20 years; Males ~3–4 years

• Recommended Experience Level: Intermediate to Advanced

• Urticating Hairs: Yes, Types I and III

• Venom Potency: Mild to Moderate (typical for New World species)

What Makes Xenesthis immanis So Special?

The Colombian Lesserblack Tarantula stands out for its bold coloration, large size, and strong feeding response. While this species is primarily terrestrial, it is known to burrow if given the opportunity, making it an opportunistic burrower in captivity. Unlike some other large terrestrial species, X. immanis is highly active, often seen moving within its enclosure at night. Its stunning purple and pink hues make it an exceptional display species in any collection.

Natural Habitat & What That Means for Enclosure Setup

Native to the humid rainforests of Colombia and Venezuela, X. immanis thrives in an environment that provides moderate to high humidity with ample ventilation. In captivity, replicating this environment is crucial—substrate should be moist but never swampy, and the enclosure should allow for burrowing opportunities while minimizing fall risks. A secure hide is essential to help this species feel safe, and regular misting or a large, overflowing water dish can help maintain proper humidity levels.

Housing & Substrate

Spiderlings

• Enclosure Size: Sling Crib, 3" Tarantula Cube, Small Slider Crib, Small Cuboid, Terrestrial Sling Crib, Slider Crib Mini, or Cuboid Mini

• Substrate: Fill at least 2/3rds of the enclosure with Terra Aranea by The Bio Dude.

• Humidity: Maintain a slightly damp substrate (but not swampy) by offering a small water dish or gently dripping water on one corner about once a week.

Juveniles

• Enclosure Size: Medium Slider Crib, 6" Tarantula Cube, 8" Tarantula Cube, or Medium Cuboid

• Substrate: Fill the enclosure from half to 2/3rds full with Terra Aranea by The Bio Dude. This provides ample space for burrowing while minimizing the risk of fall damage.

• Humidity: Keep the substrate mostly dry with a full water dish; you can occasionally overflow one corner to create a slightly damp area.

• Additional Features: Provide a half cork bark round for a secure hide and include a shallow water dish sized appropriately for the tarantula’s leg span.

Adults

• Enclosure Size: Large Slider Crib, 12" Cube, 18" Cube, or Terrestrial XL

• Substrate: Fill the enclosure from half to 2/3rds full with Terra Aranea by The Bio Dude to allow for deep burrowing while minimizing fall risk.

• Additional Features: Include a secure hide (ideally a half cork bark round), a shallow water dish, and tasteful decorations. Ensure the enclosure is wider than it is deep and has a secure, tight lid to prevent escapes or injuries.

Note: Consider using this affiliate link or entering the affiliate code TTC10 at Tarantula Cribs to save 10% on your enclosure purchases.

Temperature & Humidity

• Temperature: Keep the ambient temperature between 74°F and 80°F (23-27°C) for optimal health.

• Humidity: Maintain moderate to high humidity. Ensure that the substrate is kept moist (for spiderlings) and allow the top layers to dry between waterings (for juveniles and adults) to prevent mold growth.

Feeding Schedule

Spiderlings

• Frequency:
  Feed twice a week.

• Prey:
  Offer small prey such as flightless fruit flies, confused flour beetles, or pre-killed tiny crickets/roach nymphs. Remove any uneaten prey after 24 hours. increase the size of the prey as the spider grows. Prekill any prey that is over 2/3 the size of the sling. For more detailed information on feeding spiderlings, watch this video: How To Feed Spiderlings & Scorplings (Baby Tarantulas & Scorpions)

• Post-Molt:
  Wait 24–48 hours after a molt before feeding. Ensure that the tarantula’s fangs are solid black and its exoskeleton is not soft or shiny.

Juveniles

• Frequency:
  Feed every 7–10 days.

• Prey:
  Provide 2–3 small to medium crickets or a medium Dubia roach.

• Feeding Guidelines:

  • If the abdomen is thinner than the widest part of the carapace, feed more prey more often.

  • If the abdomen is wider than the carapace, feed less prey, less often.
    This strategy helps prevent obesity, which can lead to molting complications or increase the risk of an abdomen rupture from even a small fall.

• Post-Molt:
  Wait 3–7 days after a molt before feeding, ensuring that the tarantula’s fangs are solid black and its exoskeleton is fully hardened.

Adults

• Frequency:
  Feed every 2–3 weeks (or as needed).

• Prey:
  Offer 4–5 large crickets or one large Dubia roach.

• Feeding Guidelines:

  • If the abdomen is thinner than the carapace’s widest part, increase feeding frequency.

  • If the abdomen is wider than the carapace, reduce feeding frequency.
    This is crucial to avoid obesity, which can interfere with proper molting or cause dangerous issues such as an abdomen rupture.

• Post-Molt:
  Wait 5–10 days after a molt before feeding, ensuring that the tarantula’s fangs are solid black and its exoskeleton is fully hardened.

Breeding Xenesthis immanis in Captivity

(general outline, specifics under revision)

Sexual Maturity & Pairing

• Males: Reach maturity in 2–3 years, developing longer legs and enlarged pedipalps for sperm transfer.

• Females: Reach reproductive maturity in 4–5 years, growing significantly larger than males.

• Pre-Pairing Preparation: The female should be well-fed prior to pairing to reduce aggression. Slightly increasing humidity in the weeks leading up to pairing may encourage receptiveness.

Mating Process

• Introduce the male into the female’s enclosure at night, when they are more active.

• Males typically initiate courtship with palp drumming and leg tapping.

• If receptive, the female may respond with drumming or remain still, allowing copulation.

• Once mating is complete, the male should be removed immediately, as X. immanis females have been known to cannibalize their mates.

Egg Sac Production

• If successful, the female will produce an egg sac within 4–6 months after mating.

• The egg sac can contain 100–300 eggs, depending on the female’s size and condition.

• Maintain temperatures between 75–80°F (24–27°C) and humidity levels of 70–80% to support proper egg sac development.

• The female will aggressively guard the egg sac, and disturbing her can lead to her eating or abandoning it.

Egg Sac Handling (Optional)

• Some breeders choose to pull the egg sac after 30–40 days for artificial incubation.

• If left with the mother, 1st instar spiderlings will emerge 6–8 weeks after egg sac production, molting into 2nd instar within 3–4 weeks.

Raising Spiderlings

• Xenesthis immanis spiderlings grow quickly and require consistent humidity and ventilation.

• Provide ample substrate for burrowing, as spiderlings may display fossorial tendencies early on.

• Feed pinhead crickets, fruit flies, or small roaches every 2–3 days for optimal growth.

Challenges & Considerations

• Male mortality rate: Males typically do not live beyond a year after reaching maturity, so breeding attempts should be made as soon as possible.

• Female selectiveness: Some females may reject males outright, requiring multiple introduction attempts.

• Egg sac viability: Maintaining stable humidity and temperature is crucial to ensuring a successful hatch rate.

• Ethical breeding: Due to their limited natural range, captive breeding is essential to maintain sustainable populations in the hobby.

Final Thoughts

Xenesthis immanis is a breathtakingly large and colorful tarantula that is highly sought after in the hobby. Its bold feeding response, rapid growth, and striking coloration make it a standout species for those prepared to meet its humidity and space requirements. While not overly aggressive, its speed and defensiveness make it better suited for experienced keepers who appreciate active, display-worthy tarantulas.

Due to its restricted natural range, captive breeding efforts are crucial for preserving this species in the hobby and reducing pressure on wild populations. If you're looking for a large, tropical terrestrial tarantula with an impressive presence, X. immanis is a rewarding choice for a well-maintained collection.

Additional Recommendations

For enclosures, consider Tarantula Cribs (TTC10 for 10% off), and use Terra Aranea by The Bio Dude for substrate. For legal captive-bred tarantulas, check out Spider Shoppe (TTC10 for 10% off).