Crevice Weavers (specifically the Southern House Spider) are the ultimate masters of disguise. In Utah, they are the #1 spider responsible for "False Brown Recluse" sightings and panic calls.
Crevice weavers are unique because the males and females look like two completely different species.
The Male (The "False Recluse")They are light brown with long legs and a similar body shape to a recluse. However, they have long mouthparts (pedipalps) that stick out in front of their heads like tiny tusks or horns.
The FemaleThey are large, charcoal-black or dark gray, and velvety. They look like a miniature version of a tarantula.
The EyesUnlike the Brown Recluse (which has 6 eyes in pairs), Crevice Weavers have 8 eyes all crowded together in one tight cluster.
Crevice weavers are named for their habit of building webs in—you guessed it—crevices.
The Woolly WebThey build a very specific "starburst" web that radiates out from a hole in a brick wall or siding. The silk is fuzzy and "velcro-like" rather than sticky.
LongevityFemale crevice weavers are incredibly long-lived, often staying in the same hole or crack for up to eight years.
The WandererLike Hobo spiders, the males wander in late summer looking for mates. This is when they fall into sinks or scurry across floors, leading to "Brown Recluse" scares.
I found a brown spider with a violin shape—is it a Recluse or a Crevice Weaver?In Utah, it is almost certainly a Crevice Weaver. Crevice weavers often have a faint line on their backs that can look like a violin to the untrained eye, but their long "tusk" mouthparts are the giveaway that they are harmless.
Why is there a black 'smudge' around the holes in my brick?This is the thick, woolly web of a female crevice weaver. Over time, these webs collect dust and debris, making them look like dark stains on your home's exterior.
Do they bite?They are very reluctant to bite. Even if they do, their venom is mild and comparable to a bee sting.
