Orange Baboon Tarantula (Pterinochilus murinus) Care Sheet
The Orange Baboon Tarantula (Pterinochilus murinus), commonly abbreviated to OBT, is a striking African Old World tarantula renowned for its vivid colouration, extensive webbing and extremely fast defensive responses.
It is an impressive species for experienced tarantula keepers, but it is not suitable as a first tarantula. P. murinus is exceptionally quick, can adopt defensive postures readily, and possesses medically significant venom compared with most commonly kept New World tarantulas.
This is a species to observe rather than handle.
Quick Facts
Scientific name: Pterinochilus murinus
Common names: Orange Baboon Tarantula, OBT, Mombasa Golden Starburst Tarantula
Family: Theraphosidae
Origin: Sub-Saharan Africa
Lifestyle: Terrestrial/semi-fossorial, heavy webber
Adult leg span: Approximately 10–15 cm (4–6 in)
Activity: Primarily nocturnal/crepuscular
Temperament: Highly defensive and extremely fast
Experience level: Advanced
Lifespan: Females commonly 10–15+ years; males considerably shorter-lived
Social behaviour: Solitary
UVB: Not required
Humidity: Moderate to relatively dry, with access to drinking water
Temperature: Approximately 22–27°C under normal captive conditions
Natural Distribution
Pterinochilus murinus has a very broad African distribution. Current taxonomic records include populations from:
- Democratic Republic of the Congo
- Burundi
- Kenya
- Tanzania
- Angola
- Zambia
- Mozambique
- Zimbabwe
- South Africa
This extensive range helps explain the considerable variation seen within the species.
Several geographic colour forms are recognised within the hobby, ranging from the famous intense orange form to darker brown, grey and reddish animals.
These colour forms should not automatically be treated as separate species or subspecies.
Natural History
Orange Baboon Tarantulas occupy a variety of relatively warm African habitats including dry woodland, savannah and scrub.
They are predominantly terrestrial spiders but may construct burrows beneath rocks, logs, vegetation and other sheltered features.
One of the defining characteristics of the species is its ability to produce large quantities of silk.
In captivity an established specimen may cover much of its enclosure with dense sheets and tunnels of webbing. These structures form retreats, feeding platforms and pathways throughout the enclosure.
Providing suitable anchor points allows this natural behaviour to develop.
Adult Size
Adult females generally attain a diagonal leg span of approximately:
10–15 cm (4–6 in)
Individual size varies according to sex, genetics, feeding history and geographical form.
Mature males are usually more lightly built and have proportionally longer legs than adult females.
Lifespan
As with most tarantulas, females live considerably longer than males.
Approximate captive expectations are:
Females: 10–15 years or potentially longer
Males: Commonly several years, with a much shorter lifespan following maturity
Growth rate can be relatively fast compared with many slower-growing terrestrial tarantulas.
Temperament and Defensive Behaviour
This species has a well-earned reputation for being highly defensive.
Individuals may:
- retreat rapidly
- bolt suddenly
- assume a threat posture
- slap the substrate
- strike repeatedly if sufficiently threatened
Not every individual behaves identically, and animals provided with secure retreats may choose escape rather than confrontation.
Nevertheless, the speed and defensive capability of the species mean keepers should always assume that a rapid defensive response is possible.
The objective during maintenance should be to avoid forcing the animal into defensive behaviour.
Old World Tarantula Considerations
Pterinochilus murinus is an Old World tarantula.
Unlike many New World tarantulas, it does not rely on urticating abdominal hairs as a primary defensive mechanism.
Instead, Old World species typically rely more heavily upon:
- speed
- escape
- threat displays
- biting
This is an important distinction for prospective keepers.
Venom and Bite Risk
All tarantulas possess venom used primarily to subdue prey.
Bites from Pterinochilus murinus should be regarded considerably more seriously than bites from many commonly kept New World species.
Reported effects from Old World tarantula bites can include:
- severe local pain
- swelling
- muscle cramping or spasms
- nausea
- sweating
- elevated heart rate
- prolonged discomfort
Severity varies between bites and individuals.
There is no justification for deliberately testing temperament or attempting to handle this species.
Anyone bitten who develops significant symptoms should obtain appropriate medical advice.
Handling
Handling is not recommended.
The combination of:
- extreme speed
- unpredictable movement
- defensive behaviour
- significant bite potential
makes free-hand interaction unnecessarily risky.
The spider also gains no welfare benefit from handling.
When relocation is necessary, use controlled methods such as:
- catch cups
- appropriately sized containers
- long tools
- secure transfer areas
Never attempt to restrain a tarantula with bare hands.
Enclosure
A secure terrestrial enclosure with excellent ventilation is suitable.
For an average adult female, an enclosure in the region of:
30 × 30 × 30 cm
provides a useful starting point, although dimensions can vary depending on the animal and enclosure design.
The enclosure should prioritise usable floor space over excessive height.
Important
Tarantulas can suffer serious or fatal injuries from falls.
Avoid tall enclosures with large unsupported distances between the substrate surface and enclosure roof.
A terrestrial tarantula should never be housed in a tall arboreal-style enclosure simply for display purposes.
Security
Escape prevention is particularly important with this species.
The enclosure should have:
- a secure lid or doors
- ventilation openings too small for the spider to pass through
- no loose panels
- no unnecessary gaps
Always verify that the enclosure is properly closed after maintenance.
Because P. murinus can move extremely rapidly, enclosure servicing should be planned before opening the enclosure.
Ventilation
Good ventilation is essential.
Cross-ventilation is preferable where possible.
Constantly wet, stagnant conditions increase the risk of:
- mould
- fungal growth
- mite proliferation
- poor substrate conditions
The goal is not to create an excessively humid tropical enclosure.
Substrate
Provide approximately:
8–15 cm of substrate
for adults, depending on enclosure depth and whether the individual shows strong burrowing behaviour.
Suitable substrates include mixtures based on:
- coco fibre
- pesticide-free topsoil
- excavator-style clay/soil mixtures
- other safe tarantula substrates
The substrate should be compact enough to support burrows.
Avoid substrates containing:
- fertilisers
- pesticides
- sharp material
- strongly scented additives
Burrowing Opportunities
Although often described simply as terrestrial, P. murinus frequently creates web-lined retreats and may excavate beneath enclosure furnishings.
A partially buried hide can provide an excellent starting point.
Suitable hides include:
- cork bark
- curved cork tubes
- securely positioned bark slabs
- artificial caves
The spider will often modify the area extensively with silk.
Webbing and Anchor Points
Heavy web production is one of the most interesting aspects of keeping this species.
Provide:
- cork bark
- artificial or safe dried plants
- twigs
- leaf litter
- textured enclosure furniture
These give the spider numerous anchor points for web construction.
Over time, a well-established enclosure may become almost completely transformed by the spider.
Avoid unnecessarily destroying established webbing during routine maintenance.
Temperature
A suitable general temperature range is approximately:
22–27°C
Normal heated indoor reptile/invertebrate rooms often fall within this range.
Brief natural fluctuations are generally preferable to maintaining an unnaturally fixed temperature.
Heating
Where additional heating is required, warm the room or enclosure environment indirectly rather than placing a tarantula directly over a heat source.
Avoid placing heat mats beneath the enclosure.
Tarantulas commonly retreat downward when seeking cooler conditions, so under-tank heating can create a dangerous situation.
Any external heating equipment should be thermostatically controlled.
Humidity
This species is frequently overwatered in captivity.
Adult P. murinus generally does well with:
- good ventilation
- mostly dry substrate
- continuous access to fresh water
- occasional slight moistening of part of the substrate if environmental conditions are exceptionally dry
The entire enclosure should not be kept continuously wet.
Rather than chasing a specific hygrometer percentage, concentrate on maintaining a dry-to-moderate, well-ventilated environment with reliable drinking water.
Spiderlings may benefit from slightly more substrate moisture than established adults because they dehydrate more rapidly.
Water
Adult and juvenile tarantulas should always have access to a shallow water dish.
The dish should be:
- stable
- clean
- easy for the spider to access
Refill whenever necessary.
If the spider webs over or fills the dish with substrate, simply clean and replace it.
A water dish is not dangerous to a healthy tarantula.
Lighting
Special lighting is not required.
Normal ambient room lighting providing a natural day/night cycle is sufficient.
Avoid:
- intense enclosure lighting
- direct sunlight
- lights that significantly overheat the enclosure
UVB lighting is not considered necessary for tarantula husbandry.
Feeding
Orange Baboon Tarantulas are enthusiastic predators.
Suitable captive prey includes:
- crickets
- locusts
- appropriately sized cockroaches
- mealworms
- superworms
- other responsibly sourced feeder insects
Prey should generally be no larger than approximately the spider’s abdomen/body size.
Adult tarantulas commonly eat approximately:
one or two appropriately sized prey items every 7–14 days
Juveniles and growing spiderlings can be offered smaller meals more frequently.
Feeding frequency should be adjusted according to:
- body condition
- growth
- prey size
- temperature
- moulting cycle
Tarantulas do not need constant access to prey.
Avoid Overfeeding
An abdomen that becomes excessively distended increases the risk of injury if the spider falls.
Reduce feeding if the abdomen becomes disproportionately large.
Adult females may refuse food for extended periods without this automatically indicating a health problem.
Uneaten Prey
Remove prey that remains uneaten for an extended period.
This is particularly important when a tarantula is approaching or undergoing a moult.
Crickets and certain other feeders can injure a vulnerable freshly moulted spider.
Moulting
Tarantulas grow by shedding their exoskeleton.
Signs that a moult may be approaching include:
- reduced appetite
- refusal of food
- reduced activity
- increased time inside the retreat
- changes in body colour
- sealing of the burrow or web retreat
A tarantula may stop feeding for days or weeks before moulting.
This is normal.
During a Moult
Never disturb or handle a moulting tarantula.
Do not attempt to turn over or reposition an animal lying on its back.
Tarantulas commonly moult while lying upside down.
Maintain access to water and leave the animal undisturbed.
After Moulting
The new exoskeleton and fangs require time to harden.
Wait approximately:
5–7 days for juveniles
7–14 days for large adults
before offering prey again.
Very large specimens may require longer.
Check that the fangs have darkened before resuming feeding.
Sexing
Sex can be determined most reliably through examination of a suitable moult.
Adult males eventually develop mature male characteristics including:
- elongated proportions
- emboli on the pedipalps
- tibial structures depending on species morphology
Ventral sexing can sometimes provide an indication but is less reliable than examination of a well-preserved exuvia.
Housing Multiple Individuals
House individually.
Orange Baboon Tarantulas should not normally be maintained communally.
Cannibalism can occur.
The presence of extensive webbing does not indicate social behaviour.
Reproduction
Breeding should only be attempted by experienced keepers capable of managing fast, defensive Old World tarantulas safely.
Introduce the mature male carefully into the female’s enclosure or use a controlled breeding setup.
Courtship may involve:
- web signalling
- vibration
- tapping
- drumming
The male attempts to elevate the female sufficiently to transfer sperm using his pedipalps.
Females may attack or consume males before, during or after mating.
Constant supervision is advisable.
Egg Sacs
A successfully bred female may construct a heavily webbed retreat before producing an egg sac.
Clutch size can be substantial and varies according to:
- female size
- age
- condition
- mating success
- geographic form
Breeding this species can produce large numbers of spiderlings and should therefore not be undertaken without a realistic plan for housing and distributing offspring.
Spiderling Care
Spiderlings can be maintained individually in small, securely ventilated containers.
Provide:
- suitable substrate depth
- a small retreat
- anchor points for webbing
- appropriate moisture without saturation
Very small spiderlings can be fed:
- pre-killed small prey
- sections of larger insects
- flightless fruit flies
- very small roach or cricket nymphs
Increase enclosure size gradually as the spider grows.
Rehousing
Rehousing an OBT requires preparation.
Before beginning:
- Work in a secure, uncluttered area.
- Close doors and windows.
- Remove pets and unnecessary people.
- Prepare the new enclosure completely.
- Have multiple catch cups available.
- Use long tools rather than hands.
- Move slowly and deliberately.
Never rely upon trying to outrun or grab the spider if it bolts.
A controlled cup-to-enclosure transfer is considerably safer.
Cleaning
Tarantula enclosures require relatively little intensive cleaning.
Routine maintenance consists primarily of:
- removing prey remains
- cleaning the water dish
- removing mould where necessary
- monitoring substrate condition
Complete substrate replacement should only be performed when genuinely necessary.
Constantly destroying and rebuilding the enclosure causes unnecessary disturbance and removes established retreats.
Signs of a Healthy Tarantula
A healthy animal generally has:
- normal coordination
- a reasonably rounded abdomen
- normal feeding behaviour for its individual cycle
- intact limbs
- access to a secure retreat
- regular moulting and growth in juveniles
Extended fasting alone is not necessarily abnormal.
Dehydration
Possible signs include:
- unusually shrunken abdomen
- lethargy
- poor coordination
- abnormal posture
Always provide clean drinking water.
A severely compromised tarantula requires specialist advice rather than repeated handling or home treatment.
The Death Curl
A tarantula with its legs tightly curled beneath its body and an inability to move normally may be severely dehydrated, injured or dying.
This is different from normal resting postures and from the upside-down position associated with moulting.
Injury Prevention
Falls are one of the most preventable causes of serious tarantula injury.
Reduce risk by:
- keeping excessive vertical space to a minimum
- using deep substrate
- avoiding sharp decorations
- securing heavy enclosure furniture
A ruptured abdomen can be fatal.
Quarantine
Newly acquired tarantulas should be kept separately from existing collections initially.
Use separate tools where practical and monitor for:
- mites
- unexplained mortality
- abnormal behaviour
- fungal problems
- other signs of disease or poor condition
Wild-caught animals may present additional parasite and acclimatisation concerns.
Captive-bred specimens are preferable wherever available.
Suitability as a Pet
The Orange Baboon Tarantula is hardy and visually spectacular, but ease of husbandry should not be confused with ease of management.
Advantages
- striking appearance
- fascinating web-building behaviour
- generally robust captive husbandry
- strong feeding response
- relatively fast growth
- impressive display species
Considerations
- extremely fast
- highly defensive
- medically significant bite potential
- unsuitable for handling
- requires confidence during maintenance
- poor choice for inexperienced keepers
For an experienced keeper who respects its capabilities, Pterinochilus murinus can be one of the most rewarding display tarantulas in the hobby.
For a beginner, numerous calmer species are much more appropriate.
Legal and Responsible Ownership
Before acquiring any exotic invertebrate, check current local laws, tenancy restrictions and animal-keeping regulations.
Never release captive tarantulas into the wild.
Buy captive-bred animals from reputable sources wherever possible.
Prospective keepers should also consider whether everyone who may encounter the enclosure understands the potential risks associated with keeping a fast Old World tarantula.
Secure housing is essential.
Summary
The Orange Baboon Tarantula is one of the most recognisable Old World tarantulas in captivity.
Successful husbandry centres on:
- a secure terrestrial enclosure
- deep, suitable substrate
- excellent ventilation
- abundant web anchor points
- a dry-to-moderate moisture regime
- permanent access to fresh water
- appropriately sized live prey
- minimal disturbance
- absolutely no routine handling
Its reputation should neither be exaggerated nor dismissed.
This is not an aggressive animal actively seeking confrontation, but it is a highly defensive, extremely fast species equipped with effective venom and should be maintained accordingly.
With appropriate respect, secure husbandry and experienced management, Pterinochilus murinus makes an exceptional observational display animal.
IMPORTANT INFORMATION
This care sheet provides general husbandry guidance and does not replace species-specific research or veterinary advice. Individual requirements may vary.
If you have concerns about an animal’s health or care, consult a suitably experienced exotic or invertebrate veterinarian.
Information correct at the date of publication.
reptilecommunity.com | Revised: August 2026