Not furry either, still lovely.
Mexican Red-knee Tarantula
Brachypelma hamorii
Also called Mexican Redknee Tarantula, Red-kneed Tarantula, Brachypelma smithi (name it was long sold under)
From Western Mexico: the states of Colima, Jalisco and Michoacan, on the western slopes of the Sierra Madre Occidental and Sierra Madre del Sur, in hilly dry deciduous tropical forest.1
A friendly guide, not veterinary advice. For anything about your pet's health, ask your vet.
At a glance the quick version
Body length: females about 5.2-5.4 cm, males about 4.6-5.2 cm with legs up to about 7.5 cm long. Adult leg span is about 14 cm per a keeper care sheet; Animal Diversity Web (written under the older name B. smithi) gives an overall size of 12.7-14 cm.
Females are very long-lived, typically 25-30 years. Males live much shorter lives, about 5 to 10 years depending on the source.
Looks how to spot one
Hairy, ground-dwelling burrowing spider
A heavy-bodied, velvety black tarantula with bold banding on the legs: each leg has rings of deep orange near the knee joints, followed by paler orange-yellow and creamy bands. The abdomen is dark with brownish hairs. The carapace is mostly black with a pinkish-brown edge, or the dark area can be broken into a starburst-like pattern. Females are noticeably larger than males.13
Personality what they are like
Known as a very docile, steady tarantula. Young spiders can be a little skittish but tend to retreat rather than stand their ground. When disturbed, adults usually flick fine hairs from the abdomen as a warning rather than biting, so it is best enjoyed as a display animal with minimal handling.12
Daily activity how busy a day looks
Low. A burrower that spends much of its life in or near its burrow, waiting for prey to pass. No exercise needed beyond a suitable enclosure.13
Grooming and care the hands-on bits
No grooming needed. Keep a full water dish for juveniles and adults, remove uneaten prey, and do not feed for about 5-10 days after an adult moults. Spot-clean as needed and otherwise leave it undisturbed.2
Home where they are happiest
A terrestrial enclosure with more floor space than height, about 3-4 times the spider's leg span across for adults, filled half to two thirds with substrate so it can dig a burrow, plus a hide. Room temperature of about 21-25 C and moderate humidity, keeping part of the substrate slightly damp with constant access to water.2
Food basics what goes in the bowl
Live insects such as crickets and roaches. Spiderlings feed twice a week, juveniles every 7-10 days and adults every 2-3 weeks (a few large crickets or one large roach). In the wild it ambushes large insects and the occasional small frog or mouse from its burrow.23
Company who they like around
Solitary and territorial. Keep one tarantula per enclosure.32
The story where it all began
The name Brachypelma smithi goes back to 1897, when Frederick Pickard-Cambridge described a red-kneed tarantula from Guerrero, Mexico. A very similar spider from further north-west was named Brachypelma hamorii by Tesmoingt, Cleton and Verdez in 1997, but for two decades the two were usually lumped together as 'the Mexican redknee', and most redknees in the pet hobby were sold as B. smithi. In 2017 Mendoza and Francke used body details and DNA barcoding to show the two are separate species, and it turned out that many of the familiar captive redknees are actually B. hamorii. Because of export pressure, red-knee tarantulas were placed on CITES Appendix II in 1985, followed by the rest of the genus in 1994. Today the species is bred successfully in captivity.14
Fun facts for the dinner table
- 1
For decades most pet 'Brachypelma smithi' were really this species; DNA barcoding in 2017 finally told the two apart.4
- 2
Females can live up to about 30 years, while males usually live only a fraction of that.1
- 3
Its burrow has a planned layout: one entrance, a tunnel about three times the spider's leg span long, a moulting chamber, and a bigger room below for resting and eating.1
- 4
Red-knee tarantulas were among the animals placed on CITES Appendix II as early as 1985.1
- 5
With rather poor eyesight from its eight eyes, it 'feels' the world through vibrations picked up by the hairs on its legs, and uses chemical sensors on its palps to smell and taste.3
- 6
A single egg sac can hold around 200 to 400 eggs (figure from an account written under the older name B. smithi).3
- 7
Females spend most of their lives at home in their burrows.1
Recognised by the official bits
- Scientific description
- Described as Brachypelma hamorii by Tesmoingt, Cleton and Verdez in 1997; separated clearly from B. smithi by Mendoza and Francke in 2017.1
- CITES
- Appendix II: Mexican red-knee tarantulas were listed in 1985 (under the name B. smithi) and all Brachypelma species were added in 1994.1
- IUCN Red List (as reported by Wikipedia)
- Assessed as Vulnerable.1
Popularity Long popular in the pet trade because of its calm nature and striking colours.31
The care rhythm Furry Diary remembers it for you
A typical home-care rhythm for a Mexican Red-knee Tarantula. It is our own starting plan, not a vet's advice, and you can change every line in the app.
- Humidity checkevery 2 days
- Water dishevery 2 days
- FeedingDepends on species, size and moult stagevaries
- Spot cleanRemove leftover foodevery week
- Moult noteLeave them in peace while moulting and note it in the diaryvaries
- Substrate changeevery 6 months
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Where this comes from
Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at support@furrydiary.app and we will fix it.
- Brachypelma hamorii - Wikipedia en.wikipedia.orgused for taxonomy, range, habitat, body size, colours, temperament, lifespan, burrow structure, CITES and IUCN status, captive breeding
- Brachypelma hamorii care sheet - The Tarantula Collective thetarantulacollective.comused for enclosure, temperature, humidity, feeding schedule, leg span, lifespan, temperament
- Brachypelma smithi - Animal Diversity Web (University of Michigan) animaldiversity.orgused for size, lifespan, colours, behaviour, diet, senses, egg numbers (account predates the 2017 split, so it covers redknees in general)
- Brachypelma smithi - Wikipedia en.wikipedia.orgused for naming history, confusion with B. hamorii, 2017 revision, CITES history
Checked 2026-09-30. Text is written in our own words from these sources.