Cellar Spider

Natural Habitat

Cellar spiders are commonly found in dark, damp, and undisturbed areas. This includes cellars, basements, crawl spaces, garages, sheds, and sometimes corners of rooms inside homes. They are often found in every continent except Antarctica, adapting well to human-made structures.

Diet & Feeding

Insects and other spiders. They are opportunistic predators, catching whatever gets caught in their webs, including flies, mosquitoes, and even other spiders.

Behavior Patterns

Cellar spiders are typically reclusive, usually found hanging upside down in their irregular, tangled webs in dark, undisturbed areas. When disturbed, they often vibrate their web rapidly to deter predators or make themselves harder to see, an act often called 'whirling'. They are known to catch and eat other spiders, including more venomous ones like the black widow, proving their effectiveness as pest controllers.

Risks & Benefits

Risks: Generally considered harmless to humans. Their fangs are too small and their venom too weak to cause significant harm to humans. Bites are extremely rare and typically result in no more than a mild, temporary irritation. Potential benefits: They are natural predators of other common household pests, including other spiders, mosquitoes, and flies, helping to control insect populations indoors. This makes them beneficial inhabitants of homes.

Identified on: 8/31/2025