The Australian Funnel Web Spider Loves Rotting Logs

Those sharp, scary-looking appendages aren't fangs; they're mating spurs that only males possess. But don't relax yet! This spider's venom toxicity is still through the roof. Ken Griffiths / Shutterstock

Let's talk about the funnel web spider, one of the most notorious arachnids in the world. Known for their fast-acting venom, funnel web spiders are both fascinating and intimidating.

The family of Australian funnel web spiders includes the Sydney funnel web spider (Atrax robustus), a species with venom so toxic that it's made headlines worldwide.

That said, thanks to modern science, funnel web spider antivenom has prevented any fatalities, making encounters with these eight-legged critters far less dangerous. Those sharp, scary-looking appendages aren't fangs; they're mating spurs that only males possess.

How to Identify the Funnel Web Spider

Funnel web spiders are medium to large spiders, with body lengths ranging from 0.4 to 2 inches (1 to 5 centimeters), depending on the species.

It has a glossy black or dark brown body, with a sturdy, robust appearance. Male spiders can be distinguished by a large mating spur projecting from their second pair of legs, a feature not found on females.

Sydney funnel-web spider.
Image Created by James van den B / Getty Images

Funnel web spiders build their homes in burrows or crevices lined with silk, often featuring irregular silk trip lines radiating from the entrance.

They are sometimes confused with mouse spiders, which are also (mostly) shiny black spiders with large fangs, but mouse spiders lack the distinctive funnel-shaped web.

Is the Funnel Web Spider Dangerous?

Australian funnel web spiders, particularly the Sydney funnel web spider, are considered some of the most venomous spiders in the world. Their venom appears to be highly toxic to humans and primates, though not to most other animals.

Funnel web bites can cause severe symptoms, including pain, muscle spasms and difficulty breathing. Thank goodness for modern antivenom!

Male Sydney funnel web spider bites are more dangerous than females, due to the increased potency of their venom. However, these spiders are generally not aggressive unless threatened, so bites are uncommon and often occur when a spider feels cornered.

Where Are Funnel Web Spiders Commonly Found?

Funnel web spiders are native to eastern Australia, with several species distributed across New South Wales, Victoria and parts of South Australia. Sydney funnel webs, as their name suggests, are commonly found in and around Sydney. Northern New South Wales is another hot spot for these spiders.

Funnel web spiders often create burrows in moist, shaded environments like under rocks, rotting logs or leaf litter. During hot, dry weather, male spiders may wander into homes or even fall into swimming pools, where they can survive underwater for hours by trapping air around their bodies.

If you wanted to see a funnel web spider up close, you could visit an Australian zoo in the Sydney area, where one or two will likely be on display.

What Attracts and Deters Funnel Web Spiders?

Funnel web spiders are attracted to environments with high humidity, shelter and access to prey. Shady gardens, dense vegetation and piles of debris make excellent habitats for these spiders.

They also gravitate toward areas with toxic plants or rotting logs, where insects — an essential part of their diet — are plentiful.

To deter funnel web spiders, clear away debris and rotting wood, seal cracks around your home, and install mesh screens over drains and vents. Spider donations to antivenom programs, where experts safely collect spiders for venom research, can also help manage populations in a controlled way.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.