The Trapdoor Spider Builds Silk-lined Burrow Traps

Trapdoor spiders are closely related to tarantulas. You can probably see the resemblance. nokkaew / Shutterstock

The trapdoor spider is one of the sneakiest hunters in the arachnid world. These clever spiders are named for their unique hunting strategy: They build burrows with hinged "doors" made of soil and twigs that they use to ambush and capture prey. These burrows are lined with silk for stability.

However, according to the Australian Musuem, most trapdoor spiders don't actually prey like this and are misleadingly named. Trapdoor spiders are part of the family Ctenizidae or the family Idiopidae. They're relatives of tarantulas and share some of their burrowing habits of that spider species.

How to Identify the Trapdoor Spider

Trapdoor spiders are medium-sized arachnids with sturdy bodies and thick legs built for digging. They have a dark brown or black coloration and a shiny, rounded abdomen.

Females are usually larger than males and spend most of their lives in their burrows, while males venture out in search of mates.

Are Trapdoor Spiders Dangerous?

Trapdoor spiders look intimidating, but they are not considered dangerous to humans. While their bites can cause mild pain and swelling, they are not venomous enough to pose a serious threat.

The spider feeds on insects, small arthropods and even other predators like centipedes and scorpions, but it generally has no interest in humans.

Where Are Trapdoor Spiders Commonly Found?

a large black spider's legs peek out from a burrow — A trapdoor spider emerges from its burrow. Pong Wira / Shutterstock

Found mostly in the Southern Hemisphere, these spiders are common in places like Australia and parts of Africa and South America. The species thrive in warm, dry environments. The Australian spiders construct their burrows in soil with good drainage, often near vegetation or under rocks.

The spider's burrow serves as both a hunting ground and a safe haven from predators like birds and larger arthropods. Females may spend their entire lives — which can span several years — in the same burrow, while males roam the ground in search of mates during the mating season.

You can also see these spiders at the American Museum of Natural History in New York.

What Attracts and Deters Trapdoor Spiders?

Trapdoor spiders are attracted to areas with soft, loose soil that's easy to dig into and abundant prey. The entrance to their burrow is camouflaged with soil, twigs and vegetation, making it nearly invisible to unsuspecting prey.

They're most active at night, using their sensitive legs to detect vibrations near the entrance of their burrows, allowing them to ambush insects or small arthropods that wander too close.

To deter trapdoor spiders, reduce clutter in your yard and remove leaf litter, twigs and other debris that might provide cover for burrows. These spiders are reclusive and prefer to stay hidden, so sealing cracks and gaps around your home can also keep them outdoors where they belong.

Parasitic wasps such as the tarantula hawk also pose a significant danger to trapdoor spiders. These wasps seek out trapdoor spiders and lay their eggs on the trapdoor spider's abdomen. The wasp larvae, upon hatching, feed off the spider, eventually leading to the trapdoor spider's demise.

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