Mexican Red Knee Tarantula Care Guide (Brachypelma hamorii)
The Mexican Red Knee Tarantula (Brachypelma hamorii) is the most iconic beginner tarantula in the hobby. Its striking orange-and-black coloration, calm temperament, and extreme longevity have made it the flagship species of tarantula keeping for decades. This guide covers everything you need to keep a Mexican Red Knee successfully.
Species Overview
- Scientific name: Brachypelma hamorii
- Common name: Mexican Red Knee Tarantula
- Adult leg span: 5–6 inches
- Lifespan: Females 20–30 years; males 5–8 years
- Origin: Pacific coast of Mexico (Jalisco, Colima, Michoacan)
- Type: Terrestrial, New World
- Difficulty: Beginner
Always purchase captive-bred Brachypelma hamorii from a reputable breeder. Brachypelma species are listed under CITES Appendix II, so captive-bred animals from reputable breeders are the preferred choice for both conservation and long-term success in captivity.
Enclosure
Mexican Red Knees are terrestrial burrowers that need floor space more than height. A standard adult enclosure is 12" x 12" x 10" or similar — wider than it is tall. Avoid enclosures that are excessively tall, as falls can be fatal to a heavy-bodied tarantula.
- Substrate depth: At least 4–6 inches for adults to allow burrowing. Use a mix of coconut fiber, peat moss, and topsoil.
- Hide: Provide one cork bark hide or similar retreat. The spider will use this as a base and may burrow beneath it.
- Ventilation: Cross-ventilation is important. Avoid fully sealed enclosures.
- Water dish: A shallow water dish should always be available for adults. Spiderlings can be misted lightly instead.
See our Best Tarantula Enclosures, Best Tarantula Substrate, and Best Tarantula Hides guides.
Temperature
Mexican Red Knees do well at normal room temperature — 68–80°F is ideal. They do not require supplemental heating in most homes. Avoid sustained temperatures above 85°F. Being from a seasonally dry, warm climate, they are tolerant of temperature fluctuation within the recommended range.
Humidity
As a species from a dry scrubland habitat, B. hamorii does not require high ambient humidity. Keep the enclosure dry overall, but lightly moisten one corner of the substrate every 2–3 weeks to provide a moisture gradient. Always keep a fresh water dish available for adults. Avoid consistently damp substrate, which promotes mold and bacterial growth. Good ventilation is generally more important than maintaining a specific humidity percentage.
Feeding
Mexican Red Knees are slow-growing and do not need to be fed as frequently as faster-growing species. Feed juveniles every 5–7 days and adults every 7–14 days. Offer prey no larger than the tarantula's abdomen.
- Spiderlings: Fruit flies, pinhead crickets
- Juveniles: Small crickets, small mealworms, small dubia roaches
- Adults: Crickets, dubia roaches, mealworms, superworms (occasional)
Remove uneaten prey within 24 hours. Never feed during or immediately after a molt. B. hamorii may fast for weeks or months, particularly before a molt or during seasonal slowdowns — this is normal. See our Best Tarantula Feeding Tongs guide.
Water
Always provide a shallow water dish for adults and sub-adults. Use a shallow water dish that the tarantula can easily enter and exit — bottle caps work for spiderlings, and a small reptile water dish is appropriate for adults. Refresh the water weekly or when soiled. See our Best Tarantula Water Dishes guide.
Handling
Brachypelma hamorii is often considered one of the more handleable tarantulas due to its calm temperament, although routine handling is not recommended because even a short fall can be fatal. Handle close to the ground and never over hard surfaces. B. hamorii possesses urticating hairs on the abdomen that it may flick when stressed. These cause skin and eye irritation — avoid touching your face after handling and wash hands thoroughly.
Urticating Hairs
As a New World species, B. hamorii relies primarily on urticating hairs as a defense mechanism rather than biting. A bald patch on the abdomen indicates the spider has been flicking hairs — a sign of stress. Reduce disturbance and handling frequency if this occurs. The hairs will grow back at the next molt.
Molting
Mexican Red Knees are slow-growing and molt infrequently compared to many other species — adults may only molt once every 1–2 years. Before a molt, the spider will refuse food, become less active, and may flip onto its back inside its hide or on the enclosure floor. Do not disturb the spider during this period. Remove all live prey immediately when pre-molt signs appear. After molting, wait at least 2 weeks before offering food to allow the new exoskeleton to fully harden. See our Tarantula Molting Guide for full details.
Lifespan
Female B. hamorii are among the longest-lived tarantulas in captivity, commonly reaching 20–30 years with good care. Males live significantly shorter lives — typically 5–8 years — and will die within 1–3 years of reaching sexual maturity. This lifespan difference is one reason female Mexican Red Knees are considerably more valuable and sought-after in the hobby. See our Tarantula Lifespan guide.
Health & Common Issues
- Dehydration: Ensure a water dish is always available and the substrate has a slight moisture gradient in one corner.
- Prolonged fasting: Normal before molts and during seasonal slowdowns. Do not force-feed. Offer prey every 2 weeks and remove if refused.
- Injuries from prey: Always remove uneaten prey within 24 hours. Crickets will bite a molting or post-molt tarantula.
- Abdomen rupture: Caused by falls. Always handle close to the ground.
See our Tarantula Diseases & Health guide for more detail.
Quick Reference
| Parameter | Recommended Range |
|---|---|
| Temperature | 68–80°F |
| Humidity | Low ambient; moisture gradient in one substrate corner |
| Enclosure (adult) | 12" x 12" x 10" minimum |
| Substrate depth | 4–6 inches minimum |
| Feeding frequency | Every 7–14 days (adults) |
| Lifespan (female) | 20–30 years |
| Lifespan (male) | 5–8 years |