Asian Forest Scorpion (Heterometrus spp.) Care Sheet
Asian Forest Scorpions of the genus Heterometrus are among the largest and most commonly kept scorpions in the exotic invertebrate hobby.
They are heavy-bodied, dark-coloured tropical scorpions with powerful claws, comparatively modest venom potency and strong burrowing behaviour. Several Heterometrus species are sold under broad common names such as Asian Forest Scorpion, Giant Forest Scorpion or Malaysian Forest Scorpion, and misidentification in the pet trade is common.
For that reason, this care sheet covers Heterometrus** at genus level**. Exact adult size, colour, temperament and locality-specific requirements can vary between species, but the general captive husbandry principles are very similar.
Asian Forest Scorpions are primarily nocturnal, secretive and terrestrial. They spend much of the day inside burrows or beneath secure cover and usually become more active after dark.
Successful husbandry requires a secure terrestrial enclosure, deep moisture-retentive substrate, high humidity with good ventilation, warm stable temperatures, secure hides, access to clean water and appropriately sized captive-bred prey.
Quick Facts
Scientific name: Heterometrus spp.
Common names: Asian Forest Scorpion, Giant Forest Scorpion, Malaysian Forest Scorpion
Order: Scorpiones
Family: Scorpionidae
Origin: South and Southeast Asia, depending on species
Lifestyle: Terrestrial and burrowing
Activity: Primarily nocturnal
Adult size: Commonly around 10–15 cm, depending on species
Diet: Carnivorous
Temperature: Approximately 24–28°C
Night temperature: Approximately 22–24°C
Humidity: High, with good ventilation
Substrate: Deep, compactable, moisture-retentive substrate
Housing: Individual housing is safest
Handling: Not recommended
Experience level: Beginner to intermediate
Venom: Generally considered less medically significant than many Buthidae, but stings can still be painful
Major requirements: Deep substrate, humidity, secure hides, warmth and clean water
Species Identification
The genus Heterometrus contains multiple species that can appear very similar.
Commonly encountered names in the hobby may include animals labelled as:
- Heterometrus spinifer
- Heterometrus petersii
- Heterometrus laoticus
- Heterometrus silenus
- Other Heterometrus species
Dealer labels are not always reliable.
For breeding or species-specific record keeping, obtain animals from breeders who can provide:
- Scientific identification
- Locality information where known
- Captive-bred provenance
- Parentage where available
Appearance
Asian Forest Scorpions are generally:
- Glossy black to dark brown
- Heavy bodied
- Strongly built
- Equipped with large powerful pedipalps
The claws are one of the most distinctive features.
Compared with many highly venomous scorpions, Heterometrus species tend to rely heavily on:
their powerful pincers for prey capture and defence.
Adult Size
Adult size varies by species.
Many captive animals reach approximately:
10–15 cm in total length.
Some species may be somewhat smaller or larger.
Females are often broader and heavier than males.
Natural Distribution
Heterometrus species occur across parts of:
- India
- Sri Lanka
- Thailand
- Malaysia
- Indonesia
- Laos
- Vietnam
- Other areas of South and Southeast Asia
Exact distribution depends upon the species.
Natural Habitat
Asian Forest Scorpions are associated with:
- Tropical forest floors
- Moist soil
- Leaf litter
- Rotting wood
- Root systems
- Burrows beneath logs and stones
Their captive enclosure should reflect this humid, terrestrial lifestyle.
Burrowing Behaviour
Burrowing is a major part of natural behaviour.
A Heterometrus may:
- Dig beneath a hide
- Build a tunnel
- Create a chamber
- Block its burrow entrance
- Spend long periods underground
This is normal.
The substrate should be deep enough for genuine excavation.
Housing
Use a secure terrestrial enclosure.
Suitable housing includes:
- Glass terrariums
- Acrylic invertebrate enclosures
- Secure plastic tubs
- Purpose-built scorpion enclosures
Floor space is more important than height.
Adult Enclosure Size
For a single adult, approximately:
30 × 30 × 30 cm
is a good practical starting point.
Larger adults can be housed in:
45 × 30 × 30 cm or larger.
The enclosure should provide enough room for:
- Deep substrate
- A secure hide
- A water dish
- Some environmental variation
Juvenile Housing
Juveniles can be kept in smaller secure containers.
The enclosure should still provide:
- Deep substrate relative to body size
- A secure retreat
- Humidity
- Appropriate ventilation
Avoid enormous enclosures for tiny scorplings because they can make feeding and monitoring unnecessarily difficult.
Enclosure Security
Asian Forest Scorpions are not strong climbers on smooth glass, but enclosure security still matters.
Use a secure lid.
Check that:
- Ventilation openings are escape proof
- Decorations do not reach unsecured openings
- The lid cannot be pushed loose
- Juveniles cannot pass through mesh
Substrate
The substrate should be:
deep, compactable and moisture retentive.
Suitable components may include:
- Organic topsoil
- Coco fibre
- Soil/coco mixtures
- Excavator-style clay components in moderation
- Leaf mould
Substrate Depth
For an adult, provide approximately:
10–15 cm
of substrate.
Deeper areas can be created beneath hides.
A large adult should be able to dig a real burrow rather than merely scrape the surface.
Compact the Substrate
Lightly compact the substrate.
Very loose fluffy substrate tends to collapse and does not support stable burrows.
The substrate should remain firm enough to hold structure while still allowing excavation.
Moisture
Maintain the lower layers of substrate:
consistently moist but not waterlogged.
The surface can be slightly drier in places.
Moisture Gradient
A useful setup provides:
- One wetter side
- One slightly drier side
- Moist lower substrate throughout
This allows the scorpion to select its preferred microclimate.
Leaf Litter
A layer of pesticide-free hardwood leaf litter is highly beneficial.
It provides:
- Cover
- Naturalistic substrate structure
- Humidity retention
- Enrichment
Suitable leaves may include:
- Oak
- Beech
- Magnolia
- Other safe hardwood leaves
Hides
Provide at least one secure ground-level hide.
Suitable options include:
- Cork bark
- Half logs
- Cork tubes
- Artificial reptile hides
- Stable pieces of wood
Partially burying the hide encourages natural excavation.
Starter Burrow
A useful technique is to create a shallow cavity under a cork flat.
The scorpion can enlarge it into:
a permanent burrow.
Multiple Hides
In larger enclosures, provide more than one retreat.
Different hides can offer:
- Different moisture levels
- Different temperatures
- Different depths
Heavy Decorations
Any heavy rock or decoration must be securely supported.
Do not place heavy stones directly on loose substrate where burrowing could cause them to collapse.
Temperature
A useful captive range is approximately:
24–28°C.
Around:
25–27°C
works well for many species.
Night Temperature
A moderate nighttime drop is appropriate.
Approximately:
22–24°C
is generally suitable.
Excessive Heat
Avoid sustained temperatures around or above:
30°C.
Hot, poorly ventilated enclosures can dehydrate scorpions rapidly.
Heating
In many homes, room heating may be sufficient.
If additional heat is required, use:
thermostatically controlled external heating.
Heat Placement
Do not heat the entire base of a burrowing enclosure.
If a heat mat is used, position it on:
the side or rear of the enclosure, not underneath.
This allows the scorpion to move deeper into substrate without encountering increasing heat.
Thermostat
Any significant heat source should be controlled by:
a reliable thermostat.
Temperature Monitoring
Use a digital thermometer.
Measure temperatures at:
- Warm side
- Cooler side
- Substrate surface
Do not estimate temperatures by touch.
Humidity
Asian Forest Scorpions require:
high environmental humidity.
A useful general range is approximately:
70–85%.
However, substrate condition and ventilation are more important than chasing a single exact number.
Ventilation
High humidity must be combined with:
good ventilation.
A warm sealed container with no airflow can encourage:
- Mould
- Bacterial growth
- Stagnant conditions
- Mite outbreaks
Misting
Misting may be used to maintain humidity.
Mist:
- Substrate
- Enclosure walls
- Leaf litter
as required.
Avoid flooding the enclosure.
Drying
The enclosure should not dry completely.
At the same time, there should not be standing water throughout the substrate.
Water Dish
Always provide a:
shallow clean water dish.
Adult scorpions can drink directly from it.
Water Dish Size
The dish should be:
- Stable
- Easy to access
- Shallow enough to be safe
Avoid very deep bowls.
Water Maintenance
Replace water regularly.
Clean the dish if contaminated with:
- Substrate
- Prey remains
- Waste
Lighting
Specialised lighting is not required.
Provide a normal:
day/night cycle.
UVB
Dedicated UVB lighting is:
not required.
Nocturnal Behaviour
Asian Forest Scorpions are primarily active:
after dark.
During daylight, an established animal may remain completely hidden.
This is normal.
Feeding
Heterometrus species are:
carnivorous predators.
Suitable Prey
Appropriate captive-bred prey includes:
- Crickets
- Cockroach nymphs
- Locust nymphs
- Mealworms
- Superworms of appropriate size
Prey Size
Offer prey that the scorpion can overpower safely.
There is no need to offer very large prey.
Feeding Frequency
Healthy adults can generally be offered food approximately:
once every 7–10 days.
Juveniles can be fed somewhat more frequently.
Body Condition
Scorpions can go long periods without food.
Do not continuously add prey simply because the animal does not emerge.
Monitor:
- Body condition
- Activity
- Feeding response
Overfeeding
Excessive feeding can result in:
- Obesity
- Increased waste
- Mite problems
- Uneaten prey
Feed according to condition rather than schedule alone.
Uneaten Prey
Remove uneaten prey after a reasonable period.
This is especially important during:
premoult.
Wild-Caught Feeders
Avoid wild-caught insects.
They may introduce:
- Pesticides
- Parasites
- Pathogens
- Environmental contaminants
Use captive-bred feeder insects.
Moulting
Juvenile scorpions grow through repeated:
moults.
Adults no longer moult.
Premoult
A scorpion preparing to moult may:
- Refuse food
- Become less active
- Remain deep in the burrow
- Appear swollen
- Seal itself away
Do Not Dig It Up
If a juvenile seals itself inside a burrow:
leave it alone.
Do not excavate it simply because it has disappeared.
During the Moult
Do not:
- Handle the scorpion
- Disturb the burrow
- Introduce prey
- Flood the substrate
Freshly Moulted Scorpion
After moulting, the scorpion is:
- Pale
- Soft
- Vulnerable
The exoskeleton may take several days to harden.
Feeding After Moulting
Do not offer live prey until the new exoskeleton has:
fully hardened and darkened.
Exuvia
The discarded exoskeleton may remain inside the burrow.
It can be left in place unless easily accessible.
Handling
Routine handling is:
not recommended.
Why Avoid Handling?
Handling offers no welfare benefit and introduces risks including:
- Stings
- Pinches
- Falls
- Escape
- Stress
Pincer Strength
Asian Forest Scorpions possess:
very powerful pincers.
A pinch from a large adult can be painful and may break skin.
Sting
The sting is generally considered less medically significant than that of many Buthidae.
However, it can still cause:
- Pain
- Swelling
- Local irritation
Individual reactions vary.
Allergic Reactions
Any sting can potentially provoke a serious allergic response in a susceptible person.
If severe symptoms occur, seek medical attention.
Venom Risk
Do not describe any scorpion as:
completely harmless.
The sensible approach is:
avoid being stung.
Transfers
Use:
- A secure catch cup
- Long forceps
- A soft guiding tool
when moving the scorpion.
Catch Cup Method
Place a transparent container in front of the animal and gently guide it inside.
Never grab the scorpion by:
- Tail
- Legs
- Pincers
Individual Housing
Individual housing is the:
safest default.
Communal Housing
Some Heterometrus species are sometimes kept communally.
However, communal success is not guaranteed.
Potential problems include:
- Cannibalism
- Competition
- Feeding inequality
- Injury
- Moult disturbance
For normal home husbandry:
individual housing is recommended.
Sexing
Sexing varies between species.
Differences may involve:
- Pectine size
- Genital operculum
- Body proportions
- Shape of the chelae
Reliable sexing is easiest with experience and species-specific reference material.
Pectines
The comb-like structures on the underside of a scorpion are called:
pectines.
They are sensory organs and can also assist with sexing.
Breeding
Breeding Heterometrus is well established in captivity.
Both animals should be:
- Mature
- Healthy
- Correctly identified
- Correctly sexed
Pair Introduction
Breeding introductions should be:
closely supervised.
Do not simply place two adults together permanently.
Courtship
Scorpion courtship involves a distinctive behaviour known as:
the promenade à deux.
The male grasps the female’s pedipalps and guides her while searching for a suitable surface on which to deposit a spermatophore.
Spermatophore
The male deposits a:
spermatophore
on the substrate.
He then guides the female over it so sperm can be transferred.
After Mating
The pair should generally be separated after successful breeding.
Gestation
Scorpions do not lay eggs externally like many other arachnids.
The developing young are retained internally.
Gestation can be:
many months long.
Exact duration varies according to:
- Species
- Temperature
- Female condition
Birth
Females give birth to:
live young.
Newborn scorplings climb onto the mother’s back.
Maternal Care
The mother carries her offspring until:
their first moult.
This is normal and extremely important.
Do Not Remove Newborns
Do not remove newborn scorplings from the female immediately.
They depend upon her for support before the first moult.
First Moult
After their first moult, young scorpions gradually leave the mother’s back.
This is the point at which individual rearing can begin.
Scorpling Housing
Young scorpions can be housed in small individual containers containing:
- Moist substrate
- Fine ventilation
- A tiny hide
- Appropriate warmth
- Small prey
Scorpling Feeding
Suitable prey can include:
- Small cricket nymphs
- Small roach nymphs
- Sections of freshly killed prey for very small young where appropriate
Scorpling Humidity
Young scorpions are particularly vulnerable to:
dehydration.
Maintain stable humidity without waterlogging their small containers.
Scorpling Ventilation
Ventilation openings must be:
fine enough to prevent escape.
Growth
Juveniles grow through repeated moults.
Growth rate depends upon:
- Temperature
- Food
- Species
- Sex
- General husbandry
Cleaning
Routine maintenance should be relatively minimal.
Remove:
- Uneaten prey
- Food remains
- Excess waste
- Mouldy material
Spot Cleaning
Spot cleaning is preferable to constantly replacing the entire substrate.
Full Substrate Replacement
Complete substrate replacement should only be performed when genuinely necessary.
Unnecessary full cleaning destroys:
- Burrows
- Stable microclimates
- Established substrate structure
Springtails
Springtails can be useful in humid scorpion setups.
They help consume:
- Mould
- Small organic debris
Mites
Small numbers of harmless detritivore mites may occur.
Large mite populations often indicate:
- Excess food
- Excess moisture
- Poor hygiene
Correct the underlying cause.
Household Chemicals
Scorpions are highly sensitive to pesticides.
Keep the enclosure away from:
- Fly sprays
- Ant treatments
- Flea products
- Garden pesticides
- Cockroach killers
Aerosols
Avoid spraying near the enclosure:
- Air freshener
- Perfume
- Cleaning sprays
- Deodorising aerosols
Common Husbandry Mistakes
Common mistakes include:
- Keeping the substrate too shallow
- Using loose substrate that cannot support burrows
- Allowing the enclosure to dry completely
- Keeping the substrate permanently waterlogged
- Poor ventilation
- Providing no secure hide
- Using uncontrolled heating
- Heating from underneath
- Overfeeding
- Leaving prey with a moulting scorpion
- Digging up a sealed burrow
- Handling unnecessarily
- Grabbing the tail
- Assuming communal housing is always safe
- Breeding misidentified species
- Separating newborn scorplings from the mother too early
Are Asian Forest Scorpions Suitable for Beginners?
For a keeper comfortable with invertebrates:
yes, generally.
Asian Forest Scorpions are among the more approachable large scorpions in captivity because they have:
- Straightforward environmental requirements
- Large adult size
- Strong captive availability
- Relatively manageable venom risk compared with many Buthidae
However, they still require:
- Respectful handling procedures
- Secure housing
- Humidity management
- Understanding of moulting
They are best considered:
beginner to intermediate.
Captive Availability
Heterometrus species are:
well established within the exotic invertebrate hobby.
Captive-bred juveniles and adults are regularly available from:
- Invertebrate breeders
- Reptile expos
- Specialist exotic-pet shops
- Hobbyist collections
Captive-Bred Animals
Captive-bred animals should be strongly preferred.
Benefits include:
- Better feeding history
- Better health history
- Reduced wild collection
- More reliable species information
- Known captive husbandry
Wild-Caught Animals
Wild-caught Asian Forest Scorpions have historically been common in trade.
Potential problems include:
- Parasites
- Poor condition
- Dehydration
- Unknown age
- Misidentification
- Conservation concerns
There is little reason for the ordinary hobby keeper to prefer wild-caught animals where good captive-bred stock is available.
Correct Identification
The pet trade has a long history of selling different Heterometrus species under the same common name.
Do not assume that:
“Asian Forest Scorpion”
identifies the species.
For breeding, keep animals with reliable scientific identification separate.
Do Not Cross Species
Do not intentionally breed different Heterometrus species together.
Maintain separate labelled lines.
Legal Considerations
Regulations concerning scorpion ownership vary between jurisdictions.
Check current rules before:
- Purchasing
- Selling
- Transporting
- Importing
- Exporting
live scorpions.
Never Release Captive Scorpions
Never release captive:
- Adults
- Juveniles
- Scorplings
into the environment.
Responsible Ownership
Before obtaining a Heterometrus, make sure you can provide:
- Secure terrestrial housing
- Deep compactable substrate
- High humidity
- Good ventilation
- Stable warmth
- Secure hides
- Clean drinking water
- Captive-bred prey
- Safe transfer equipment
- Long-term care
Educational Value
Asian Forest Scorpions provide excellent opportunities to observe:
- Burrowing
- Nocturnal hunting
- Prey capture with pedipalps
- Moulting
- Pectine use
- Courtship
- Live birth
- Maternal care
- Juvenile development
Display Value
A naturalistic enclosure containing:
- Deep soil
- Cork
- Leaf litter
- Plants
- Low light
can create an excellent forest-floor display.
However, remember that an established scorpion may spend much of the day:
inside its burrow.
Summary
Asian Forest Scorpions of the genus Heterometrus are large tropical scorpions widely maintained within the captive invertebrate hobby.
They are primarily terrestrial and burrowing animals, so enclosure design should emphasise:
deep substrate, secure hides, high humidity and good ventilation.
For a single adult, an enclosure around 30 × 30 × 30 cm provides a useful starting point, with larger animals benefiting from 45 × 30 × 30 cm or greater.
Provide approximately 10–15 cm of compactable substrate, ideally with a partially buried cork hide to encourage natural burrowing.
Maintain temperatures around:
24–28°C, with approximately 22–24°C at night.
Humidity should generally remain around:
70–85%, but good ventilation is essential.
Provide a clean shallow water dish at all times.
Adults can generally be fed appropriately sized captive-bred insects approximately:
once every 7–10 days.
Juveniles can be fed somewhat more frequently.
A scorpion that seals itself inside a burrow may be preparing to moult and should not be disturbed.
Routine handling is not recommended. Asian Forest Scorpions possess powerful pincers and can sting, even though their venom is generally considered less medically significant than that of many more dangerous scorpion groups.
Individual housing is the safest default.
Breeding involves the characteristic scorpion promenade à deux, followed by internal development and live birth. Newborn scorplings remain on the mother’s back until completing their first moult and should not be removed prematurely.
Because multiple similar-looking Heterometrus species occur in the hobby, reliable identification and accurate breeding records are important.
For keepers seeking a large, impressive and well-established captive scorpion, Heterometrus can be an excellent choice.
IMPORTANT INFORMATION
This care sheet covers Heterometrus** at genus level** because multiple similar species are commonly sold under the name Asian Forest Scorpion.
Exact adult size, colour, behaviour and some husbandry details vary between species.
Provide a terrestrial enclosure with deep compactable substrate, ideally around 10–15 cm for adults.
Maintain the substrate moist enough to support burrowing and high humidity, but never permanently waterlogged.
Provide good ventilation.
Maintain temperatures approximately 24–28°C and avoid prolonged temperatures around or above 30°C.
Do not heat the enclosure from underneath.
Always provide a clean shallow water dish.
Feed appropriately sized captive-bred insects and remove uneaten prey when moulting is suspected.
Do not disturb a scorpion that has sealed itself inside a burrow.
Routine handling is not recommended. Large Heterometrus have powerful pincers and can sting.
Individual housing is the safest approach.
During breeding, supervise introductions and separate adults after mating.
Do not remove newborn scorplings from the mother’s back before their first moult.
Prefer captive-bred animals and avoid purchasing poorly identified wild-caught stock where captive-bred alternatives are available.
Maintain correctly identified species separately and do not intentionally cross species.
Check current legislation concerning possession, transport, import and export.
Never release captive adults, juveniles or scorplings into the environment.
Information correct at the date of publication.
reptilecommunity.com | Revised: August 2026