White-tailed spiders are slim, dark grey, night-hunting spiders with a pale spot at the tip of the abdomen. The name covers two closely related Australian species, Lampona cylindrata and Lampona murina (family Lamponidae). Both also live in New Zealand, where they were introduced from Australia. They don’t build webs to catch prey, they feed mostly on other spiders, and they often wander into houses in the warmer months.
Their reputation for causing “flesh-eating” ulcers is not supported by the best available evidence. A study of 130 confirmed bites found pain and a red mark were common, but no necrotic ulcers.
White-tailed spider quick facts
| Feature | Details |
|---|---|
| Scientific names | Lampona cylindrata (L. Koch, 1866) and Lampona murina L. Koch, 1873 |
| Family | Lamponidae |
| Native range | Australia |
| Introduced range | New Zealand (both species) |
| Body length | Males about 12 mm, females about 18 mm (body only, not including legs) |
| Web | No prey-catching web; makes only temporary silk retreats |
| Activity | Mostly at night |
| Main prey | Other spiders |
| Medical significance | Bites are usually minor and short-lived; no confirmed link to necrotic ulcers |
How to recognise a white-tailed spider
The white tip is the feature everyone remembers, but it should never be the only clue. Several other dark ground-hunting spiders have a similar slim shape, and the pale markings can be faint on older adults. Look for a combination of features:
- Body shape: a long, narrow, cylindrical abdomen, often described as cigar-shaped.
- Colour: dark reddish-brown to grey overall. The upper side of the abdomen is grey, usually with a white spot at the tip and two pairs of faint pale spots further forward. These forward spots tend to be less obvious in adults.
- Legs: dark orange-brown with banding.
- Size: a body length of roughly 12 mm in males and up to about 18 mm in females.
- Males: a hard, narrow plate (scutum) on the front part of the abdomen.
- Behaviour: a fast, roaming hunter seen on floors, walls and ceilings at night, not sitting in a web.
- Location: Australia or New Zealand. A “white-tailed spider” reported anywhere else is almost certainly a different spider.
L. cylindrata and L. murina look very alike, and their ranges overlap in south-eastern Australia. Telling them apart reliably usually requires a specialist looking at the spider’s reproductive structures under magnification. For most purposes, “white-tailed spider” or “Lampona species” is an accurate answer.
If you have found a dark spider with pale markings and you’re not sure what it is, our guide to narrowing down a black spider with white spots walks through the clues that matter most. The general spider identification guide explains how to combine body shape, eyes, habitat and behaviour.
Where white-tailed spiders live
Distribution
| Species | Australia | New Zealand |
|---|---|---|
| Lampona cylindrata | Southern Australia, including south-east Queensland, New South Wales, Victoria, South Australia, Tasmania and Western Australia | Introduced; widespread in the South Island since about 1980 |
| Lampona murina | Eastern Australia, from north-east Queensland to Victoria | Introduced; present in the North Island for more than 100 years |
Both species arrived in New Zealand accidentally from Australia. The genus Lampona also contains many other Australian species, but these two are the ones people usually mean when they say “white-tailed spider.”
Habitat
Outdoors, white-tailed spiders shelter under bark and rocks, in leaf litter, logs and garden debris. They live in bushland as well as suburban gardens.
In summer and autumn they are often found in and around houses. Indoors they tend to hide in sheltered spots during the day: inside clothing, towels and bedding, in shoes, under items left on the floor, and in cool tiled areas. They come indoors partly for shelter and partly because houses hold the spiders they eat. Seeing one inside does not mean a house has an “infestation”; they are wanderers rather than colony-forming spiders.
What white-tailed spiders eat
White-tailed spiders are specialist hunters of other spiders. Instead of waiting in a web, they roam at night and attack spiders they find. Recorded prey includes:
- black house spiders (family Desidae);
- daddy-long-legs spiders (family Pholcidae);
- redback spiders (family Theridiidae);
- curtain-web spiders (family Dipluridae).
This diet explains why they turn up near the webs of other spiders around homes, sheds and windows. It also means that a house with a lot of web-building spiders can attract more white-tailed spiders. For a wider look at how spiders find food indoors, see what house spiders eat.
Behaviour and life cycle
White-tailed spiders are vagrant hunters. They are mostly active at night and spend the day tucked into a temporary silk retreat or any tight, dark space they can find. Dense tufts of fine hairs (scopulae) at the tips of their legs let them walk easily across smooth or sloping surfaces, which is why they are sometimes seen on walls and ceilings.
Females spin flat, disc-shaped egg sacs, each holding up to about 90 eggs. The young spiderlings disperse and grow through a series of moults before reaching adult size.
Are white-tailed spiders dangerous?
White-tailed spiders are venomous, like almost all spiders, and their bite can hurt. But the evidence shows that bites are usually minor.
What a confirmed bite usually looks like
The most useful evidence comes from an Australian study published in the Medical Journal of Australia in 2003. Researchers followed 130 bites where the spider was caught at the time and identified by an expert as a Lampona species. Of these bites:
- all caused pain or discomfort, which was severe in about a quarter of cases;
- 83% caused a red mark and 44% caused itchiness;
- only 8% caused swelling, and 9% caused mild general symptoms such as nausea or headache;
- effects typically lasted about a day, although some people had a painful or itchy red patch that persisted longer;
- none caused a necrotic ulcer, and no infections were confirmed.
The same study found that most bites happened indoors, at night, during the warmer months, and usually when the spider was trapped against the skin by clothing or bedding.
Where the “flesh-eating” reputation came from
From the 1980s onward, white-tailed spiders were blamed in medical reports and the media for serious skin ulcers, a condition sometimes called necrotising arachnidism. In most of those cases, nobody saw or caught the spider, so there was no direct evidence that a white-tailed spider was involved. Victoria’s Better Health Channel notes that medical studies have not been able to confirm the link.
This matters because skin ulcers have many other causes, including bacterial and fungal infections, poor circulation, diabetes and burns. Blaming a spider can delay the right diagnosis. Anyone with a wound that is spreading, ulcerating or not healing should see a doctor rather than assume it is a spider bite.
What to do if you are bitten
This section is general information, not medical advice. If you are unsure what bit you, or symptoms are severe or getting worse, contact a doctor or your local poisons centre.
For a bite you are confident came from a white-tailed spider, Australian and New Zealand health services give similar first-aid advice:
- Wash the bite with soap and water, or clean it with antiseptic.
- Apply a cold pack or ice wrapped in cloth (not directly on the skin) to ease pain and swelling.
- Seek medical advice if the area becomes very red or painful, blisters, looks infected, forms an ulcer, or you feel generally unwell.
If the spider could have been a funnel-web or mouse spider (in Australia), the first aid is different: apply a pressure immobilisation bandage, keep the person still, and call 000. Health authorities also advise against cutting the bite or applying a tourniquet.
Who to contact:
- Australia: Poisons Information Centre, 13 11 26 (24 hours). For an emergency, call 000.
- New Zealand: National Poisons Centre, 0800 POISON (0800 764 766). For an emergency, call 111.
Any severe allergic reaction, such as difficulty breathing or swelling of the face or throat, is an emergency regardless of the spider involved. For more general background, see the Spider Bite & Danger section.
How to reduce indoor encounters
Because most bites happen when a spider is pressed against skin by fabric, a few simple habits make a real difference:
- Shake out clothes, towels and shoes that have been left on the floor, especially in summer and autumn.
- Keep clothing and bedding off the floor where possible.
- Check bedding before getting in if you have seen white-tailed spiders in the house.
- Reduce the number of web-building spiders around windows, eaves and indoor corners, since these are the white-tailed spider’s food supply.
- To remove a white-tailed spider, trap it under a jar or container, slide a piece of card underneath, and release it outdoors. Avoid picking it up by hand.
White-tailed spiders also help keep other spider numbers down, which is one example of the wider role spiders play in ecosystems. Read more in why spiders are important.
Frequently asked questions
Do white-tailed spiders build webs?
No. They don’t build webs to catch prey. They hunt by roaming at night and only spin small, temporary silk retreats to rest in.
Are white-tailed spiders found in New Zealand?
Yes. Both Lampona murina and Lampona cylindrata were introduced from Australia. L. murina has been in the North Island for over a century, and L. cylindrata has been widespread in the South Island since about 1980.
Do white-tailed spider bites cause flesh-eating ulcers?
The best evidence says this is very unlikely. In a study of 130 confirmed bites, none led to a necrotic ulcer. Persistent or worsening skin wounds should be checked by a doctor, because other causes are far more likely.
Are white-tailed spiders aggressive?
There is no good evidence that they seek out people. Most bites happen when a spider is accidentally trapped against the skin, for example inside clothing or bedding.
Why do I see white-tailed spiders inside in summer?
They are most active in the warmer months and wander widely at night looking for prey. Houses offer both shelter and the other spiders they eat.
Is a white-tailed spider the same as a white-tail in other countries?
In everyday use, “white-tailed spider” refers to the Australian Lampona species described here. If you are outside Australia and New Zealand, a spider with a pale rear end is very likely something else, so use location along with other features to identify it.
Browse more species profiles in Spider Types, or learn how spiders find and catch food in Spider Diet.
References
- World Spider Catalog. Lampona cylindrata (L. Koch, 1866). Natural History Museum Bern. wsc.nmbe.ch/spec-data/20275
- World Spider Catalog. Lampona murina L. Koch, 1873. Natural History Museum Bern. wsc.nmbe.ch/species/13676
- Australian Museum. White-tailed Spider. australian.museum/learn/animals/spiders/white-tailed-spider/
- Isbister GK, Gray MR. White-tail spider bite: a prospective study of 130 definite bites by Lampona species. Medical Journal of Australia. 2003;179(4). mja.com.au
- Australasian Arachnological Society. Myths: White-tailed spider. australasian-arachnology.org/myths/white-tailed-spider/
- Better Health Channel (Victoria State Government). Spiders. betterhealth.vic.gov.au
- HealthEd, Health New Zealand. Spiders in New Zealand. healthed.govt.nz/resource/spiders-new-zealand
- Te Ara – The Encyclopedia of New Zealand. Spiders and other arachnids. teara.govt.nz
