Can bite, and it stings for a while, but it is not medically significant and there is no lasting harm. It is a widow relative, which is where the name and most of the alarm come from.
We identify, we don't diagnose. If you've been bitten or stung and symptoms develop, or you're worried, seek medical attention.
Size6–10 mm body
MarkingsPurplish-brown to near-black, glossy but not jet black · No hourglass — sometimes a pale crescent across the front of the abdomen
WhereGarages, sheds, under sinks and behind furniture.
What it is not
A false widow is most often confused with species that are medically significant. If you are trying to rule those out, check these:
Purplish-brown to near-black, glossy but not jet black
No hourglass — sometimes a pale crescent across the front of the abdomen
Rounded abdomen, similar shape to a widow
Tangled web in a low, dark corner
Where you’ll find it
Widespread across the United States, particularly in the west and along both coasts. It is a European species that has travelled well.
Garages, sheds, under sinks and behind furniture.
How it behaves
It builds a tangled web in a low, dark, undisturbed place and stays in it. Like a true widow it hangs upside-down, which is part of why the two get confused. It is a slow, retiring spider that will retreat rather than defend, and it also preys on other spiders, including widows.
What a bite looks like
A red mark with local swelling that fades within a day or two. It does not ulcerate.
A sharp sting at the time, with soreness for a few hours. Some people report a dull ache in the limb, but the widespread cramping of a true widow bite does not occur.
We identify, we don't diagnose. See a doctor if the site becomes infected or the reaction is unusually strong.
A skin mark cannot confirm which animal caused it. Read the bug bite and sting guide for the limits and the symptoms that should end an online search.
You’ve found one indoors
Nothing needed. If you would rather it were gone, a vacuum removes web and spider together. Reducing clutter in garages and under sinks removes the harbourage it prefers.
Common questions
Why is it called a false widow?
Because it is a close relative of the true widows and looks broadly similar — round glossy abdomen, tangled web, hangs upside-down. What it lacks is the red hourglass and the medically significant venom.
How do I tell it from a black widow?
Colour and marking. A false widow is purplish-brown rather than jet black, often with a faint pale crescent across the front of the abdomen, and it has no hourglass underneath.
Is a false widow bite dangerous?
No. It stings and can ache for a few hours, but it is not medically significant and causes no lasting harm.
Анатолий Озерной /Anatoly Ozernoy · CC-BY-SA