The Sydney funnel-web spider (Atrax robustus) is a large, glossy black ground spider that lives in silk-lined burrows in and around Sydney, New South Wales. It is one of the few spiders anywhere whose bite can be life-threatening to people, which is why it has such a strong reputation. That reputation needs context, though: bites are uncommon, an effective antivenom has been used since 1981, and no deaths have been recorded since it became available.
Quick facts
- Scientific name: Atrax robustus O. Pickard-Cambridge, 1877
- Family: Atracidae (Australian funnel-web spiders), a group within the mygalomorph spiders
- Range: the Sydney region of New South Wales, Australia, mainly from the Central Coast south to the Georges River
- Size: about 2–4 cm (0.8–1.6 in) in body length, according to the Australian Museum
- Lives in: silk-lined burrows in cool, damp, sheltered ground
- Most often seen: wandering males in the warmer months, roughly November to April
- Medical significance: a suspected bite is a medical emergency in Australia — call 000
One name, three species: the 2025 split
For decades, “Sydney funnel-web” was used for funnel-webs found across a wide area, from the Newcastle region down to the Southern Highlands. A 2025 study led by researchers at the Leibniz Institute for the Analysis of Biodiversity Change and the Australian Museum used genetic data and male and female reproductive anatomy to show that this broad “species” was actually three:
| Species | Common name | Where it occurs |
|---|---|---|
| Atrax robustus | Sydney funnel-web | Central Coast (around Tuggerah Lake) south to the Georges River and west to about Baulkham Hills, with some records from the Blue Mountains and Wollongong |
| Atrax montanus | Southern Sydney funnel-web | Mainly south and west of Sydney, from the Watagans to Bowral and into the upper Blue Mountains; overlaps with A. robustus in places |
| Atrax christenseni | Newcastle funnel-web | Only known from within about 25 km of Newcastle |
These three look extremely similar. The researchers separated them using features of the male palps and female reproductive organs, so you should not expect to tell them apart from a photo of a spider in your garden. For safety purposes the split changes nothing: a large black spider in any of these areas should be treated as a possible funnel-web.
The split also means that older venom and medical research described as “Atrax robustus” may include spiders now placed in the other two species. Figures quoted below from earlier studies use the older, broader meaning of the name.
How to recognize a Sydney funnel-web
No single feature identifies a funnel-web, and color certainly doesn’t — many unrelated Australian spiders are dark brown or black. Look for several of these clues together, and remember that location matters first. Funnel-webs of the genus Atrax are found only in south-eastern Australia.
- Glossy, dark body: the carapace (head-and-thorax shield) is shiny and almost hairless-looking, dark brown to black, with no clear pattern.
- Finger-like spinnerets: the silk-spinning organs at the rear of the abdomen are long and visible from above.
- Closely grouped eyes: the eyes sit together in a small cluster near the front of the carapace.
- Heavy, forward-pointing fangs: like other mygalomorphs, funnel-webs strike downward with fangs that are parallel to each other.
- Male leg spur: adult males have a distinct spur on the second pair of legs.
- Defensive pose: when disturbed, a funnel-web often rears up on its back legs and raises its front legs, showing its fangs.
Males and females
Females are heavier-bodied and spend most of their long lives in or near their burrows. Males are slimmer, have relatively longer legs and a shorter lifespan, and leave their burrows once mature to search for females. Because males are the ones that wander, they are the funnel-webs most likely to turn up in gardens, garages, swimming pools, or occasionally inside a house.
Spiders often mistaken for funnel-webs
The Australian Museum notes that mouse spiders, trapdoor spiders, and black house spiders are frequently confused with funnel-webs. The clues below can help, but they are a guide rather than a guarantee. If a large black spider has bitten someone, skip identification and follow the first aid steps further down. For a general method, see our spider identification guide.
| Spider | Helpful clues | How it differs from a funnel-web |
|---|---|---|
| Sydney funnel-web (Atrax robustus) | Shiny black or dark brown; long finger-like spinnerets; eyes closely grouped; males have a spur on leg 2; silk trip-lines around the burrow entrance | — |
| Mouse spiders (Missulena) | Stout and black; very high, bulging head and jaws; some males have a red head or a bluish abdomen | Eyes spread across the front of the head; short spinnerets; males have no leg spurs |
| Trapdoor spiders (several families) | Ground-dwelling burrowers, often brown or dark; burrow may have a door or a small, neat silk collar | In males, the modified leg is the first leg, not the second |
| Black house spider (Badumna insignis) | Smaller (about 0.9–1.8 cm body length); grey hairs on the carapace; lacy, matted webs around window frames and wall cracks | Not a mygalomorph or a close relative; webs are on walls and windows rather than in ground burrows |
Mouse spider bites are also treated with the same first aid as funnel-web bites in Australia, so the practical response to a bite is the same for both.
Where Sydney funnel-webs live
Under the 2025 definition, Atrax robustus is centered on the northern suburbs of Sydney. Its main range runs from the Central Coast south to the Georges River and west to about Baulkham Hills. The Australian Museum notes that its southern range has shrunk, with recent southern records limited to the Bankstown–Mortdale area.
Within that range, it prefers bushy suburbs and both open and closed eucalypt forest and woodland, often on south- or east-facing slopes or in shady gullies — places that stay cool and humid.
Its burrow is a silk-lined tube dug into moist ground, typically under logs and rocks or in other sheltered crevices. Lines of silk spread out from the entrance across the ground. These act as trip-lines: when a beetle, cockroach, millipede, or small lizard touches one, the spider rushes out, grabs the prey, and drags it back inside. Funnel-webs do not build sticky catching webs. For more on how different spiders choose their homes, see our spider habitat section.
Behavior and seasonal activity
Most Sydney funnel-web encounters follow a seasonal pattern. In the warmer months — mainly summer and autumn, roughly November to April — mature males leave their burrows at night to look for females. Many funnel-web bites are recorded during this period.
A wandering male needs to find dark, damp cover before the day warms up, or it risks drying out and being eaten by birds or lizards. That is why males sometimes shelter in odd places, such as a gap under a rock, a garage, or a shoe left outside overnight. Houses built on concrete slabs seem to be entered more often.
Males also regularly fall into swimming pools. A funnel-web sitting motionless at the bottom of a pool may still be alive: the Australian Museum reports they can survive at least 30 hours underwater.
Funnel-webs belong to the mygalomorph spiders, the same broad group as tarantulas and trapdoor spiders. You can read more about this ancient lineage in our overview of mygalomorph spiders.
How dangerous is a Sydney funnel-web bite?
The Sydney funnel-web is venomous, not poisonous: it injects venom with its fangs. Its reputation comes mainly from one component of the male’s venom, a neurotoxin known as robustoxin (δ-atracotoxin-Ar1). This toxin strongly affects the nervous system of humans and other primates, while most other mammals are much less affected. Female Sydney funnel-web venom lacks this component.
The real-world picture is more measured than the headlines suggest:
- Deaths: 13 deaths from funnel-web bites were recorded in Australia before antivenom became available in 1981, seven of them children. The male Sydney funnel-web was linked to most of them. No deaths have been recorded since 1981.
- Not every bite causes serious illness: a 2005 review of expertly identified funnel-web bites found severe envenoming in about 17% of bites attributed to the Sydney funnel-web. The rate was higher for some tree-dwelling funnel-webs in the genus Hadronyche.
- Males caused the severe cases: the same review recorded no severe envenoming from female funnel-webs. The Australian Museum still advises that female bites should not be assumed safe, because not all funnel-web species show this difference.
- Antivenom works: the 2005 review found funnel-web antivenom effective and safe, including in children.
Severe symptoms usually begin within the first hour. In the 2005 review, the median time to onset in severe cases was 28 minutes, and the authors recommend observing anyone with a suspected funnel-web bite for at least four hours. Symptoms can include:
- severe pain at the bite site;
- tingling or numbness around the mouth and tongue;
- heavy sweating, drooling, and watery eyes;
- muscle twitching or spasms;
- nausea, vomiting, abdominal pain, and headache;
- a fast or slow heart rate and high or low blood pressure;
- difficulty breathing, confusion, or reduced consciousness.
A funnel-web bite is a nervous-system emergency, not a skin-wound problem. Spreading skin ulcers or “bull’s-eye” lesions are not typical of funnel-web envenoming, and an unexplained skin wound should not be assumed to be a spider bite. For an overview of how spider bites are assessed more generally, see our spider bite and danger section.
First aid for a suspected funnel-web bite in Australia
If someone is bitten by a big black spider in eastern Australia, treat it as a medical emergency. Call 000 and ask for an ambulance, even if there are no symptoms yet.
Australian health services recommend pressure immobilization for suspected funnel-web and mouse spider bites:
- Move the person away from the spider, lie them down, and keep them as still as possible.
- Apply a firm, wide elastic bandage over the bite.
- Apply a second bandage over the whole limb, starting at the fingers or toes and working toward the body. It should be firm, like a sprained-ankle bandage, but not cut off circulation.
- Splint the limb to stop it moving, and keep the person still.
- Mark the bite site on the bandage or skin, note the time of the bite, and wait for the ambulance.
Do not try to catch the spider. If it has already been killed or is safely trapped, it can help hospital staff confirm what it was, but treatment should never wait for identification. Pressure immobilization is not recommended for most other Australian spider bites, including redback bites. For advice on a bite that is not an emergency, the Poisons Information Centre can be reached on 13 11 26 from anywhere in Australia.
This page is general information for readers, not medical advice. Follow the instructions of emergency services and your doctor.
Reducing the chance of an encounter
Most people living in funnel-web areas never have a problem, and these spiders play a normal part in local bushland ecosystems. A few simple habits lower the odds of a bite during the wandering season:
- Bring shoes, gloves, and clothing inside at night, or shake them out before use.
- Wear gloves and closed shoes when gardening, moving rocks or logs, or clearing leaf litter.
- Check the pool before swimming, and remove spiders with a pool scoop rather than by hand.
- Seal gaps under doors and around garage entries if spiders often find their way in.
Common questions
Is the Sydney funnel-web the most venomous spider in the world?
It is often described that way, and the male’s venom is exceptionally potent to primates. But “most venomous” depends on how venom is measured and on which animal. What matters more for people is that bites are uncommon, only a minority cause severe illness, and antivenom is highly effective.
Are Sydney funnel-webs found outside Sydney?
Under the current definition, Atrax robustus is limited to the Sydney region. Other funnel-web species in the genera Atrax and Hadronyche occur elsewhere in eastern Australia, from Tasmania to north Queensland. Australian funnel-webs are not native anywhere outside Australia.
Do funnel-webs chase people?
No. A funnel-web will rear up and may bite if it is handled, trapped against skin, or cornered, but it does not hunt people. Bites typically happen when a spider is handled or accidentally pressed against skin, for example inside a shoe or glove.
Looking for other spiders? Browse our spider types section.
References
- World Spider Catalog. Atrax robustus O. Pickard-Cambridge, 1877. Natural History Museum Bern. wsc.nmbe.ch/spec-data/19755 (accessed November 2026).
- Loria, S.F., Frank, S.-C., Dupérré, N., Smith, H.M., Jones, B., Buzatto, B.A. & Harms, D. (2025). The world’s most venomous spider is a species complex. BMC Ecology and Evolution 25: 7. doi.org/10.1186/s12862-024-02332-0
- Australian Museum. Sydney’s famous funnel-web spider splits into three! (13 January 2025). australian.museum
- Australian Museum. Sydney Funnel-web Spider. australian.museum
- Australian Museum. Funnel-web Spiders. australian.museum
- Australian Museum. Mouse Spiders. australian.museum
- Australian Museum. Black House Spider, Badumna insignis. australian.museum
- Isbister, G.K. et al. (2005). Funnel-web spider bite: a systematic review of recorded clinical cases. Medical Journal of Australia 182(8). mja.com.au
- healthdirect Australia. Spider bites (reviewed October 2024). healthdirect.gov.au
- NSW Poisons Information Centre. Pressure immobilisation. poisonsinfo.nsw.gov.au
- NSW Poisons Information Centre. Have I been bitten by something poisonous? Spiders. poisonsinfo.nsw.gov.au
