Giant Huntsman (Heteropoda maxima)
Measured from foot to foot, no spider on Earth is longer. The giant huntsman spans about 30 centimetres — a dinner plate — yet it was unknown to science until 2001, when it was found in the limestone caves of central Laos. It remains one of the most geographically restricted large spiders in the world, and one of the least dangerous.
By Dr Richard J. Pearce (PhD)Published July 24, 2019Updated September 13, 2026✓ Reviewed by Dr. James Watuwa
In this guide
Physical description and identification
The giant huntsman is built on the same plan as every other member of the huntsman family — a flat body and laterigrade legs that swing out sideways and rotate forward like a crab's — but stretched to an extreme. Almost all of its record-breaking size is leg. The body itself would sit comfortably in a matchbox; it is the span that makes people stare.
Adults
- Size: the leg span reaches about 30 cm (12 inches), the longest measured for any spider. Body length is far more modest: roughly 3 cm in males and up to about 4.6 cm in females, which are the larger sex.
- Color: pale yellowish brown to ochre overall, with dark spots and blotches scattered irregularly across the carapace and abdomen. A darker band usually runs behind the eye region, and the legs are banded with brown or grey.
- Legs: extremely long and slender in proportion to the body, held out and angled forward. The spider can run across rock and squeeze its flattened body into narrow crevices, and the long limbs give it an unusually wide sensory reach in total darkness.
- Distinguishing the sexes: apart from size, the reliable characters are genital. In the mature male, the cymbium — the cup that holds the palpal organ — is roughly three times as long as the tegulum beneath it, and this proportion is one of the features used to separate the species from its relatives.
Eggs
The female lays around 200 eggs and encloses them in a tough, oval silk sac. She guards it in a sheltered spot on the cave wall or under rock and does not abandon it, and, like other Heteropoda species, opens the sac to help the spiderlings out when they are ready.
Spiderlings
Newly emerged young are pale and translucent and darken with every molt. They disperse into the cracks and the rubble of the cave floor, where they grow slowly on a diet of small cave invertebrates. Reaching full adult size takes a considerable time — a spider with a 30 cm span is an old animal.
Hunting instead of a web
No web is built. The giant huntsman hunts on foot in near-total darkness, using vibration and the touch-sensitive hairs on its long legs rather than sight, and runs down cave crickets, cockroaches and other invertebrates. Silk is reserved for the egg sac, a dragline and a thin retreat.
Where the giant huntsman lives
This is a genuinely rare situation for a famous spider: Heteropoda maxima is known only from the limestone karst of Khammouan Province in central Laos and the caves immediately around it. Claims that it also occurs in Australia, Africa or the southern United States are a persistent error — those records belong to the widespread pantropical cane spider, a completely different member of the same genus. Nothing with a 30 cm leg span lives in Thailand, Texas or Queensland.
Its habitat is the caves themselves and the shaded rock, dead wood and stumps at their entrances. It is a cave dweller rather than a true cave-adapted animal: its eyes are normal and pigmented and it has none of the extreme adaptations of blind cave species, so it is best described as living in the twilight zone and the dark passages just beyond. Because that habitat is confined to a small band of karst, the total world range of the species is tiny — a point covered in more detail in our guide to where spiders live.
Are giant huntsman spiders venomous?
Yes, and like every huntsman it uses that venom on insects. It is not considered dangerous to humans. No medically significant envenomation has been reported from Heteropoda maxima or from any member of the genus, and the venom of the better-studied cane spider — its close relative — is built around peptides that target insect ion channels rather than mammalian ones.
Size is not a guide to danger in spiders. The giant huntsman is larger than a black widow by an enormous margin and vastly less harmful, because the widow's venom contains a neurotoxin aimed at vertebrate nerve endings and the huntsman's does not.
Can giant huntsman spiders bite?
It can, but human encounters are very rare — the species lives in remote caves, not in houses. A frightened giant huntsman runs first; biting requires the spider to be cornered, handled or pressed against skin. When a bite does happen the fangs are large, so it hurts: reports compare it to a bee or wasp sting, with local redness, itching and swelling that settle over a few hours.
Wash the bite with soap and water, apply a cold pack and use a simple painkiller if needed. Watch for spreading swelling or signs of infection, and seek medical care if either appears or if you feel generally unwell. There is no antivenom because none is required, and no home remedy is appropriate — cutting, sucking or burning a spider bite causes more damage than any huntsman ever will.
Perspective: the giant huntsman is frequently listed among the world's scariest spiders purely on size. By the measure that matters — medical outcome — it sits with the harmless species, alongside the Avondale spider and the other large huntsman spiders that appear in films precisely because they look alarming and are safe to work with.
Ecological importance and behavior of the giant huntsman
Cave ecosystems run on imported energy — bat guano, flood debris and organic matter washed in from outside — and they support dense populations of crickets, cockroaches and other scavenging invertebrates. The giant huntsman sits at the top of that invertebrate food chain. As the largest free-running predator in these passages, it exerts real control over the insect populations that process the cave's organic input, and its presence is a useful indicator of an intact cave system.
Diet: cave crickets and cockroaches make up the staple, alongside beetles, moths and other invertebrates. Near cave entrances large individuals will take small geckos and skinks, a habit shared with other big huntsman spiders.
Natural predators: birds and lizards hunting at the cave mouth, large centipedes, and spider-hunting wasps that paralyse a spider and seal it in a nest chamber with a single egg. Egg sacs are vulnerable to parasitoid wasps.
Conservation: a species confined to one small karst region is inherently fragile. Limestone quarrying, hydropower development and heavy, unmanaged cave tourism are the main pressures, and collection for the pet trade adds to them. The species has not been assessed by the IUCN, which reflects a lack of survey data rather than a lack of concern.
Relationship with humans: essentially none. Most people will only ever see this spider in a photograph, and the sensible response to meeting one in a cave is to let it walk away.
Similar spiders and how to tell them apart
| Spider | How it differs from the giant huntsman |
|---|---|
| Cane spider (Heteropoda venatoria) | The same genus and the source of most misidentifications. Far smaller at a 7–10 cm span, more evenly brown, and pantropical rather than confined to Laos. It carries a pale cream band above the jaws. |
| Other Heteropoda species | Dozens of Asian species share the build. Size, the dark band behind the eyes and the proportions of the male palp separate H. maxima; most relatives have spans under 15 cm. |
| Avondale spider (Delena cancerides) | A large Australasian huntsman that lives in social colonies under bark. Greyer, with a span around 15 cm, and never found in caves. |
| Goliath birdeater | A South American tarantula. Heavier and far bulkier, with thick hairy legs and a similar or slightly smaller span. It is the heaviest spider; the giant huntsman is the longest. |
| Rain spider (Palystes superciliosus) | A southern African huntsman with an 11 cm span and black-and-yellow banded leg undersides. |
| Green huntsman (Micrommata virescens) | The same family at the opposite extreme: a bright green European species barely 16 mm long that hunts in grass by day. |
Quick facts
| Distribution | Endemic to Laos; known only from the limestone karst of Khammouan Province and its immediate surroundings. |
|---|---|
| Habitat | Limestone caves and cave entrances, on rock walls, dead wood and stumps in the twilight and dark zones. |
| Diet | Cave crickets, cockroaches, beetles, moths and other invertebrates; occasionally small geckos and skinks near entrances. |
| Predators | Birds and lizards at cave entrances, large centipedes and spider-hunting wasps; parasitoids attack the egg sac. |
| Lifespan | Estimated at around two years, possibly longer for large females. |
| Web | None. Silk is used only for the egg sac, the dragline and a thin retreat. |
| IUCN status | Not evaluated. The restricted karst range makes it vulnerable to quarrying, development and cave tourism. |
Did you know?
- The species was described in 2001 by the German arachnologist Peter Jäger, of the Senckenberg Research Institute, from material collected in a Laotian cave. Its name, maxima, simply means "the largest".
- Before its discovery the Australian Beregama aurea was generally regarded as the largest member of the huntsman family.
- It holds the record for leg span, not for bulk: the Goliath birdeater is much heavier, and comparisons between the two appear in almost every list of the biggest spiders in the world.
- A cave animal with normal, pigmented eyes is unusual. The giant huntsman navigates by touch and vibration, so its eyes matter far less than the sensory hairs along its legs.
- Individuals have turned up in the pet trade, which is a real concern for a species with a world range measured in a few dozen kilometres of karst.
In summary, the giant huntsman is a record holder with an unusually small footprint: the longest-legged spider known, restricted to one cave system in Laos, harmless to people, and dependent on a limestone landscape that is being quarried and developed faster than it is being surveyed.
Frequently asked questions about the giant huntsman
What is the leg span of a giant huntsman spider?
About 30 cm, or 12 inches, from the tip of one leg to the tip of the opposite leg — the longest measured for any spider. The body is far smaller, roughly 3 cm in males and up to about 4.6 cm in females, so almost all of that record-breaking size is leg.
Are giant huntsman spiders dangerous to humans?
No. They are venomous in the way almost all spiders are, using venom to subdue insects, but no medically significant envenomation has ever been reported from this species or its genus. They are not aggressive, live in remote caves, and bite only if cornered or handled.
What does a giant huntsman spider look like?
It has a pale yellowish-brown body with irregular dark spots and a darker band behind the eye region. The legs are extremely long and slender in proportion to the body, banded with brown or grey, and angled forward in a crab-like posture. Females are larger than males.
Where are giant huntsman spiders found?
Only in Laos, in the limestone caves of Khammouan Province and the karst immediately around it. Reports placing the species in Australia, Africa, Texas or Florida are misidentifications of the pantropical cane spider, a much smaller relative in the same genus.
How does a giant huntsman spider hunt?
On foot and in the dark. It builds no web at all, and instead runs down cave crickets, cockroaches and other invertebrates using vibration and the touch-sensitive hairs along its long legs rather than eyesight. Silk is reserved for the egg sac, a dragline and a thin retreat.
What happens if a giant huntsman spider bites you?
The fangs are large, so it hurts — most descriptions compare it to a bee or wasp sting — and the site typically reddens, itches and swells for a few hours. Wash it, apply a cold pack and take a painkiller if needed. Seek care if swelling spreads or the wound becomes infected.
How many eggs does a female giant huntsman lay?
Around 200, enclosed in a tough oval silk sac. The female guards the sac in a sheltered spot on the cave wall or under rock rather than abandoning it, and she opens it with her fangs when the spiderlings are ready to emerge.
Is the giant huntsman the biggest spider in the world?
It is the largest by leg span. By weight and bulk the Goliath birdeater of South America is considerably bigger, with a much heavier body and thicker legs. The two are regularly compared, and which one counts as the biggest depends entirely on how you measure.
When was the giant huntsman spider discovered?
It was described in 2001 by the German arachnologist Peter Jäger, working at the Senckenberg Research Institute, from specimens collected in a cave in Laos. Before that the Australian Beregama aurea was generally considered the largest member of the huntsman family.
Is the giant huntsman spider endangered?
It has not been formally assessed by the IUCN, largely because survey data are scarce. Its world range is confined to a small area of limestone karst, which makes it inherently vulnerable to quarrying, hydropower development, unmanaged cave tourism and collection for the pet trade.
References
- World Spider Catalog (2026). Heteropoda maxima Jäger, 2001. Natural History Museum Bern. wsc.nmbe.ch/spec-data/41261/taxon
