Xenesthis immanis

🔤 Taxonomy

Xenesthis immanis (Ausserer, 1875) is the accepted name. It was originally described as Lasiodora immanis. Xenesthis colombiana was once synonymized with it but was restored as a separate species in 2022; older labels and photographs may therefore use X. immanis too broadly.

English common names used in the hobby:

• Colombian lesserblack tarantula
• Lesserblack tarantula

📌 Description

This is a very large New World terrestrial and opportunistic burrower from Colombia and Venezuela. Large females may reach 18-23 cm diagonal legspan, with a deep dark body, pale leg striping, and violet to magenta tones around the carapace and legs. Females may live 15-20 years; mature males are smaller-bodied and much shorter lived.

Its striking size comes with a strong feeding response, considerable speed, abundant urticating hairs, and moisture-sensitive husbandry. It is not a handling animal. The keeper must be comfortable moving a large spider with a catch container and maintaining deep humid substrate without producing stagnant conditions.

☠️ Venom

There is no good clinical evidence that X. immanis venom is medically significant, but the bite of a spider this size can produce deep punctures, pain, swelling, and infection risk. The venom itself is poorly characterized, and individual reactions cannot be predicted.

Urticating hairs are the more common hazard. Airborne hairs can cause severe itching and are particularly dangerous to eyes and airways. Never handle the spider, keep the enclosure below face height, wear gloves and eye protection when stripping a webbed enclosure, and wash tools separately. After a bite or hair exposure, seek urgent medical care for eye involvement, breathing trouble, faintness, severe or spreading pain, or systemic symptoms. Do not use a tourniquet.

🌍 Distribution

World Spider Catalog gives Colombia and Venezuela as the native range. The 2022-2023 revision of Xenesthis clarified that some material previously combined under X. immanis represents distinct species, so hobby locality labels deserve caution.

The species is associated in husbandry references with humid tropical forest floor and sheltered soil retreats. Captive care should provide a large shaded terrestrial footprint, a starter burrow beneath cork, deep moisture-buffering substrate, and clean airflow. High atmospheric humidity without a moist soil reservoir is unstable, while a sealed wet tank is hazardous.

🌡 Climate across the native range

Monthly climate normals from reviewed GBIF occurrence locations:

Weather data by WorldClim v2.1 · Monthly normals queried by Herpeton Academy from raster values; relative humidity is derived from vapor pressure and mean temperature.

Location references use GBIF.org occurrence data where available; original occurrence records retain their source dataset licenses.

⚖️ Legal status

The official CITES Appendices and current EU wildlife-trade annexes were checked on 2026-08-05; Xenesthis immanis was not found in them. The Bern Convention is not relevant. Local dangerous-animal rules may nevertheless restrict large venomous invertebrates, and building or rental agreements may impose additional conditions.

Prefer captive-produced stock. Keep the invoice, breeder identity, scientific name, locality or lineage label if claimed, photographs, and import or transfer documents. Current taxonomic separation within Xenesthis makes traceable labels valuable for both legal records and future breeding decisions.

🤌 Husbandry

Keep one spider per enclosure. A practical adult minimum is about 45 x 35 x 30 cm, with more floor area for an exceptionally large female. Fill at least 12-18 cm with substrate so the spider can excavate and the empty height remains low enough to prevent a damaging fall. Use a secure locking lid: a large spider can lift poorly fitted panels.

Mix unfertilized soil, coco fibre, and a clay-bearing component, press it firmly, and insert a broad cork half-round as a starter retreat. The lower layers should retain moisture without releasing water when squeezed. Leave enough open surface for the animal to turn and for prey to be retrieved.

Quarantine new stock for at least 8 weeks with separate long tongs, water container, and catch equipment. Record weight or abdomen condition, meals, refusals, molts, feces, mites, flies, and coordination. Large imported tarantulas can hide dehydration or transport injury beneath dense setae; give water and security before testing the feeding response.

Maintenance should happen inside a clear larger tub or closed room with a catch bucket ready. Touch prey with tongs before reaching in because the spider may strike at vibration. Never pin, grasp, or free-handle it. A sealed burrow is not permission to excavate; it normally indicates rest or premolt.

💡 Lighting

No UVB or dedicated basking light is needed. Give 10-12 hours of indirect ambient light and an uninterrupted dark period. A dim external plant light is acceptable only if temperatures remain stable at the surface and retreat.

Keep the enclosure away from direct sun. Large dark enclosures can absorb heat quickly even when the room feels comfortable.

🌡 Heating and temperature

Maintain about 23-27°C by day, with access to 20-23°C and a similar night range. A burrow lets the spider choose a cooler buffered layer, so do not heat the substrate from below.

Warm the room if possible. Otherwise use a thermostatically controlled low-power source on one side and verify it with digital probes. Temperatures above 28°C are unnecessary; combined with damp stagnant air they can cause rapid decline. A cool short period is safer than an unregulated hot lamp.

💧 Humidity and water

Keep lower substrate damp and allow the top layer to dry partially between waterings. Practical readings may fall around 70-85%, but the measurable goal is a moisture gradient with no standing water, condensation film, or sour smell. Cross-ventilation should continue near substrate level.

Provide a broad, heavy, shallow dish at all times. Pour water along the enclosure edge or overflow the dish periodically so it penetrates the lower layer without entering the burrow. Never spray the spider. If the enclosure dries completely, rehydrate in stages; flooding dry tunnels can collapse them and trap the animal.

🌿 Enclosure and decoration

Use a sturdy cork hide, leaf litter, and light artificial foliage. Secure anything that could shift when excavated. Avoid rocks, hard fall hazards, aromatic wood, sharp wire, and mesh lids that can trap tarsal claws.

This species produces much waste and prey debris. Remove boluses with long tongs, rinse the dish regularly, and improve airflow rather than adding cleanup chemicals. Springtails may assist but cannot make a waterlogged enclosure safe.

🪳 Feeding

Spiderlings may take small roach nymphs, pinhead crickets, or pre-killed pieces twice weekly. Juveniles often feed every 5-7 days during rapid growth. Adults should be offered one large roach, locust, or several appropriately sized crickets about every 10-21 days, adjusted to abdomen width.

Expect a powerful response and keep fingers and the water bottle outside striking range. Remove uneaten prey within 24 hours. Stop feeding after refusals, darkening, or retreat sealing. Wait until the fangs are completely black after molt—often 7-14 days for a large adult—before offering food. Vertebrate prey and vitamin or calcium powders are unnecessary.

🩺 Common problems

• A wrinkled abdomen or tucked posture can indicate dehydration; provide clean water and restore lower-layer moisture gradually.
• Constant wall climbing often reflects saturated substrate, insufficient usable floor area, or no acceptable retreat.
• Mold, mites, and phorid flies follow retained boluses, excessive feeding, stale air, or waterlogging.
• Extreme abdomen size increases the chance of rupture in a fall; reduce meals and remove hard hazards.
• A sealed retreat and long fast are normal around molt. Do not dig out the spider.
• A fall, hemolymph leak, severe hair exposure, poor coordination, or failed molt requires prompt help from an exotics veterinarian familiar with arachnids.

Household insecticides, flea products, aerosols, and essential oils can be fatal and must never be used nearby.

📌 Conclusion

Xenesthis immanis is an impressive advanced display tarantula, not simply a larger version of an easy terrestrial. It needs a spacious low enclosure, deep moisture-buffering earth, strict hair and escape precautions, and disciplined feeding throughout a potentially two-decade female lifespan.

📚 Sources and further reading

• World Spider Catalog entry for Xenesthis immanis — accepted taxonomy and Colombia/Venezuela range, accessed 2026-08-05
• GBIF species entry for Xenesthis immanis
• Sherwood et al. 2023: taxonomy of Xenesthis
• Tarantula Collective care sheet for Xenesthis immanis
• Tom’s Big Spiders: keeping moisture-dependent tarantulas
• CITES Appendices and EU wildlife-trade regulation — checked 2026-08-05