The Complete Guide to Keeping Mexican Red Knee Tarantulas

The Mexican Red Knee Tarantula (Brachypelma hamorii, formerly Brachypelma smithi) is one of the most iconic and widely recognised tarantulas in the world. Known for its striking black body contrasted with vivid orange-red knee joints, this species is a staple in the hobby and often recommended for beginners.

Native to the Pacific coast of Mexico, these tarantulas inhabit dry scrublands and forests, where they live in burrows and emerge primarily at night. With their calm disposition and hardy nature, Mexican Red Knees are considered one of the best entry points into tarantula keeping.

What Is a Mexican Red Knee Tarantula?

The Mexican Red Knee is a terrestrial New World tarantula prized for its colouration and relatively docile temperament.

They are:

• Medium to large: Adults reach 12–15 cm leg span

• Terrestrial: Ground-dwelling with occasional burrowing

• Slow-growing: Especially compared to many other species

• Generally docile: Though still capable of defensive behaviour

As a New World species, they possess urticating hairs, which they may flick when threatened.

Enclosure Requirements

Tank Size

Mexican Red Knees require more floor space than height.

• Spiderlings: Small vials or tubs

• Juveniles: 15–20 cm enclosures

• Adults: Minimum 30 x 30 x 30 cm enclosure

A general guideline is 2–3 times the spider’s leg span in floor space.

Enclosure Type

A simple, well-ventilated terrestrial enclosure works best.

Suitable options include:

• Glass terrariums

• Plastic tubs with cross ventilation

• Acrylic enclosures

Ensure the enclosure is secure, as tarantulas can climb and push loose lids.

Substrate

Substrate should allow for comfort and light burrowing.

Recommended substrates:

• Coco fibre (coir)

• Topsoil (chemical-free)

• Soil mixes

Provide 8–12 cm depth for juveniles and adults.

Keep the substrate mostly dry with a slightly moist corner.

Temperature and Humidity

Mexican Red Knees prefer relatively dry conditions.

• Temperature: 22–26°C

• Humidity: 60–70%

Humidity can be maintained with a water dish and occasional light misting of one area.

Good ventilation is essential to prevent damp conditions.

Lighting

No special lighting is required.

• Ambient room light is sufficient

• Avoid direct sunlight

They are nocturnal and prefer subdued lighting.

Decor and Hiding Spots

Providing a hide helps reduce stress.

Include:

• Cork bark hide

• Half logs or artificial shelters

• Light leaf litter

While adults may spend time in the open, a hide should always be available.

Avoid tall structures to prevent injury from falls.

Diet and Feeding

Mexican Red Knees are reliable feeders.

Suitable Prey:

• Crickets

• Locusts

• Dubia roaches

• Mealworms (occasionally)

Feeding Schedule:

• Spiderlings: Every 3–5 days

• Juveniles: Once or twice weekly

• Adults: Every 7–10 days

Prey should be appropriately sized, no larger than the abdomen.

Remove uneaten prey after 24 hours, especially during premoult.

Provide a shallow water dish at all times.

Behaviour and Temperament

This species is known for its calm nature, though individual temperament can vary.

Typical behaviour:

• Slow movement

• Occasional hair flicking

• Periods of inactivity

They are often tolerant but should still be treated with respect.

Handling considerations:

• Handling is possible but not recommended

• Risk of urticating hair irritation

• Risk of injury from falls

Observation is always safer than handling.

Moulting

Moulting is essential for growth.

Signs of premoult:

• Refusal of food

• Darkening abdomen

• Reduced activity

During moulting:

• The spider may lie on its back

• Do not disturb

After moulting:

• Wait 7–14 days before feeding

• Fangs must harden fully

Stable conditions and access to water are key.

Breeding

Breeding Brachypelma hamorii is possible but requires patience.

• Males mature faster and live shorter lives

• Females can produce egg sacs with many spiderlings

• Growth is slow compared to many species

Due to their popularity, many individuals in the hobby are captive-bred.

Common Health Issues

Mexican Red Knees are hardy but can encounter problems.

Watch for:

• Dehydration

• Lethargy

• Failed moults

• Bald patches (from hair flicking)

Most issues arise from incorrect humidity, lack of water, or poor ventilation.

Lifespan and General Care

• Females: 20–30 years

• Males: 5–7 years

• Growth rate: Slow

They are long-lived and require a long-term commitment.

Tank Mates

Tarantulas should always be housed alone.

• Cannibalistic behaviour is common

• Cohabitation leads to stress or injury

This species is strictly solitary.

Legal Considerations

Mexican Red Knees are protected under CITES (Convention on International Trade in Endangered Species).

• Ensure your specimen is captive-bred

• Purchase from reputable sources

• Documentation may be required in some regions

Responsible sourcing helps protect wild populations.

Pros and Cons

Advantages:

• Striking appearance

• Generally calm temperament

• Hardy and beginner-friendly

• Long lifespan

Considerations:

• Slow growth

• Can flick irritating hairs

• Not a handleable pet

• Long-term commitment

Conclusion

The Mexican Red Knee Tarantula is a classic species that has earned its reputation as one of the best tarantulas for beginners and experienced keepers alike. Its stunning colouration, calm demeanour, and straightforward care make it a standout choice in the hobby.

While it may not be the fastest-growing or most active species, its longevity and ease of care more than make up for it. With proper setup and consistent care, Brachypelma hamorii can be a rewarding and enduring addition to any collection.