Noble False Widow Spider - What You Need to Know 2025

A new venomous pest has quietly crept into the corners of New Zealand homes and gardens. The noble false widow spider (Steatoda nobilis), one of the world’s most invasive arachnids, has now been officially confirmed in Aotearoa — and it’s spreading fast.

First detected in Porirua in late 2024, this spider is already making itself at home across Christchurch, Nelson, Waikato, and Northland. While it’s not aggressive and bites are rare, experts are raising concerns over its venomous bite and potential links to antibiotic-resistant infections.

If you're a homeowner, tenant, or property manager, here's what you need to know about this uninvited guest — including how to spot it, where it hides, and how to respond if you think you've found one.

What Is the Noble False Widow Spider?

Originally from the Canary Islands and Madeira, the noble false widow spider has successfully colonised large parts of Europe, the Americas, and now New Zealand. It gets its name from its resemblance to the more dangerous black widow spider, though it’s generally less harmful.

However, this spider isn't harmless.

According to Professor Steven Trewick, evolutionary ecologist at Massey University, the venom of S. nobilis contains similar neurotoxins to the black widow. "It’s not an aggressive spider," he says, "but it will bite in defence." Most bites cause minor symptoms like swelling, redness, and pain, but some have been linked to:

• Tissue necrosis
• Nausea
• Low blood pressure
• Mobility issues
• Secondary infections resistant to antibiotics

This last point is particularly worrying — infections caused by bites may not respond to standard treatment.

Similar Looking Spiders (and How to Tell Them Apart)

Because the noble false widow looks similar to other spiders already common in New Zealand, it’s easy to confuse it with harmless species. Here are a few spiders it resembles — and how to spot the difference:

Black Cobweb Spider (Steatoda capensis)

• Already established in NZ
• Looks similar, but smaller and darker
• Less potent venom than S. nobilis
• Common in sheds and garages

Katipō Spider (Latrodectus katipo)

• Native and endangered
• Black with a distinct red stripe on the back
• Very rare and mostly found near sandy coastal areas

Common House Spider (Badumna insignis)

• Slightly fuzzier appearance
• Builds messy webs in corners and eaves
• Not considered dangerous

Differences Between Male and Female Noble False Widow Spiders

Size & Appearance

• Females are larger, with a more rounded, bulbous abdomen.
  • Body length: approx. 7–15mm
  • More prominently marked with a pale cream/beige pattern on a dark brown body.
• Males are smaller and more slender.
  • Body length: approx. 5–10mm
  • Often have longer legs relative to body size and are a bit more agile.

Colouration

• Both sexes have a shiny, dark brown to purplish-black appearance, but:
  • Females usually have more distinct markings on the back of the abdomen (a pattern that looks like a skull or shield).
  • Males may appear more faded and less glossy.

Behavior

• Females tend to stay in one place — usually within their web, often under pots, crevices, or sheltered spaces.
• Males are more active and mobile, especially during mating season.
  • You’ll often see them wandering at night, on walls or footpaths, looking for females to mate with.

Lifespan

• Females live longer, sometimes up to 2–3 years.
• Males usually die shortly after mating and rarely live beyond a year.

Bite Risk

• Females are more likely to bite if disturbed because they stay put in one location.
• Males are less likely to bite, simply because they roam more and are less defensive of a fixed territory.

Tip: The noble false widow has a shiny, bulbous body, usually dark brown to black with cream or beige markings, and relatively long legs. If you’re unsure, take a clear photo and send it through to us - office@totalpestcontrol.co.nz

How Did It Get Here?

The spread of the noble false widow reflects larger patterns of globalisation and climate change. Increased trade, warmer temperatures, and shifting ecosystems are making it easier for invasive species to establish themselves in new regions.

In fact, a 2019 ecological model predicted this spider could survive in parts of New Zealand — and that prediction is now becoming reality.

What Should You Do If You See One?

If you think you’ve spotted a noble false widow spider, don’t panic — but don’t ignore it either. Here’s what you should do:

1. Take a photo: Get a clear image of the spider (ideally from above).
2. Report it: Upload your sighting to iNaturalist NZ — this helps researchers track its spread.
3. Avoid touching it: If possible, trap it using a container and slide a card underneath, but don’t handle it with bare hands.
4. Call a professional: If you’ve seen more than one, or you’re concerned about a growing population, it’s time to bring in pest control.

Where You’ll Find the Spider

The noble false widow spider is thriving in urban environments, especially in places where people spend time outside. They prefer dark, sheltered areas and are excellent at hiding in everyday places around your property.

Here’s where you’re most likely to find them:

• Under pot plants
• Beneath tarpaulin or garden covers
• In fence crevices
• Around outdoor furniture
• Along garden beds and compost bins
• Crawling on exterior walls at night
• On the ground near sheds, garages, or wood piles

The males are more mobile, and can often be seen wandering at night in search of mates.

Why You Should Act Now

While the noble false widow isn’t out to get you, it’s a venomous and invasive species with the potential to disrupt local ecosystems and pose health risks to pets and people. Left unchecked, it may become a permanent fixture in New Zealand — especially in warmer regions.

If you’re in Wellington or surrounding areas, and think your home, garden, or rental property may be harbouring unwanted spiders, our team at Total Pest Control is here to help. We use eco-friendly, low-toxicity treatments that are safe for families, pets, and the planet.

Final Thoughts

The arrival of the noble false widow is more than just a creepy headline — it’s a signal that our local environments are changing. Whether you’re a homeowner, a landlord, or a tenant, staying informed and acting early is the best way to stay ahead of this pest.

Seen something suspicious?
Upload it to iNaturalist NZ
Or contact us for professional advice and treatment