Megaphobema robustum

🔤 Taxonomy

Megaphobema robustum is usually sold as the Colombian giant redleg. It is distinctive, but imported or old-stock animals should still be labeled with source and date.

English common names used in the hobby:

• Colombian giant redleg
• Colombian giant tarantula

📌 Description

Megaphobema robustum is a New World tarantula kept mainly as a display invertebrate. Adult size is usually 7-9 cm body, 18-20 cm legspan, and lifespan is females 12-20 years; males shorter after maturity. It should not be handled routinely. Even species considered calm can bolt, fall, bite, or flick urticating hairs when stressed. The keeper’s job is to provide a secure enclosure, stable moisture gradient, safe fall height, and enough privacy for normal feeding and molting.

🌍 Distribution

Colombia, mainly humid forest and forest-edge ground habitats where it uses retreats and leaf litter.

For keepers, the range is mainly a reminder to provide shelter, moisture choice, warmth, water, and reliable security.

Distribution is a clue to habitat use, not a demand for unstable enclosure conditions. Focus on retreats, moisture choice, warmth, and reliable security.

⚖️ Legal status

As checked against current official sources in April 2026, Megaphobema robustum is not currently listed in the CITES Appendices, and no species-specific EU wildlife-trade Annex listing was found. It is not relevant to the Bern Convention unless a country applies separate native-wildlife rules. Local rules on ownership, import, sale, transport, breeding, invasive-species control, dangerous-animal licensing, and proof of lawful origin may still apply; keep purchase and breeding records.

🧭 Life stage differences

Babies or slings should start in smaller secure enclosures such as small ventilated cup for slings, upgraded to deeper juvenile boxes. Smaller starter housing makes feeding, molts, hydration, and waste easier to monitor. Adults need the full planned enclosure, stronger locks or lids, and more stable environmental zones. Do not buy a young animal unless the adult housing, food supply, and legal responsibilities are already realistic.

This species is famous for defensive displays, so the enclosure should reduce confrontation. Give a retreat that can be inspected indirectly, use side access when possible, and avoid deep maintenance while the spider is exposed.

Adult enclosures should be low, stable, and escape-proof, with modest open height, reliable ventilation, and no heavy decor that could cause a fall injury.

For spiderlings and juveniles, stability matters more than display. Keep the container small enough to locate prey and check molts, but include cover and a moisture choice so the animal is not forced to sit in the open.

🤌 Husbandry

House one animal per enclosure. A practical adult enclosure is 40 x 30 x 30 cm for one adult, with limited fall height. Larger is useful when it creates more usable movement, better gradients, and safer maintenance. Use secure ventilation and stable furnishings. Keep simple notes on feeding, molts, weight changes, and behaviour, and quarantine new animals before adding them to the collection.

💡 Lighting

A clear 10-12 hour day-night cycle is useful. Ordinary room light is enough for tarantulas; UVB and bright basking lamps are unnecessary. Avoid visible night lights and any lamp that dries the enclosure or overheats retreats.

🌡 Heating and temperature

Aim for 23-26 °C and avoid hot, dry enclosure conditions. Measure with digital probes and use an infrared thermometer for any warmed surfaces. Any supplemental heat should be controlled by a thermostat. Tarantulas are usually safer with warm room temperatures or gentle side heat rather than hot lamps or under-tank pads.

💧 Humidity and water

Humidity target: 65-80% with a water dish, moist lower substrate, and ventilation. Keep fresh water available in a stable dish sized for the animal. Keep moisture useful, not stagnant. Chronic dryness risks dehydration and bad molts; constantly wet substrate brings mold, mites, and poor air quality.

🌿 Enclosure and decoration

Provide a warm retreat, cooler retreat, water, safe texture for molting, and enough cover that the animal can move without feeling exposed. Juvenile setups should be simple enough to inspect but not bare. Adult enclosures must be built for strength, stable furniture, secure doors or lids, and safe cleaning access. Limit fall height for heavy terrestrial tarantulas. Use deep substrate, keep open space modest, and make sure lids, ventilation panels, and access points close securely.

🪳 Feeding

Feed roaches, crickets, locusts, and occasional worms sized conservatively. Let body condition set the feeding pace; eager feeders can still be overfed. Spiderlings eat smaller meals more often; adults usually eat less often and should stay lean rather than swollen. Remove uneaten prey promptly, especially before a molt.

🥚 Breeding

Pairing should be supervised because defensive behaviour and cannibalism risk are real. Keep offspring labels clear and avoid casual hybrid or uncertain-locality projects. Breeding should use healthy mature animals with known identity and lawful origin. Keep dates, pairings, offspring numbers, and transfer records, and do not produce more young than can be housed and placed responsibly.

🩺 Common problems

Common problems include dehydration, bad molts, overheating, mites, fall injuries, refusal to feed with visible weight loss, and stress from exposure or poor security. Warning signs include a shriveled abdomen, leaking injury, failed molt, swollen joints, twisting posture, sudden lethargy, or repeated frantic escape attempts. Consult an exotic-animal veterinarian for severe weakness, injury, swelling, failed molt, or prolonged refusal to feed with decline in body condition.

📌 Conclusion

Megaphobema robustum needs adult-sized planning from the start, not only interest in the juvenile stage. Secure housing, measured conditions, appropriate feeding, and basic records make long-term care predictable.

📚 Sources and further reading

• GBIF species backbone entry for taxonomy and distribution context
• CITES Appendices, checked April 2026
• EU wildlife-trade references, checked April 2026