Brown Recluse Spiders: What to Know

What Is a Brown Recluse Spider?

Brown recluse spiders (Loxosceles reclusa) are the most common brown spider in the U.S. As their name suggests, these spiders prefer to be left alone. They tend to live in indoor and outdoor spaces where people don’t go most of the time.

If the spider feels trapped, especially when it’s pressed between your skin and clothing or bedding, it may bite you.

Brown recluse spiders are one of two spiders found in the U.S. that can cause real trouble if they bite you. They make harmful venom that may cause a painful sore at the site of the bite. It may cause even more severe symptoms in some people. If you have a run-in with a brown recluse, it’s wise to have a doctor check you out, just in case.

What does a brown recluse spider look like?

Brown recluse spiders are light brown. A mature spider has a dark violin-shaped area on its back, right behind the eyes (but young spiders don’t have this mark yet).

It may be bigger than other spiders that you’re used to seeing. Its body can range in size from 1/4 to 1/2 inch, and its long legs make it appear even larger. Its legs aren’t spiny or banded, which can help you tell it apart from similar spiders.

Also, most spiders have eight eyes, but a brown recluse spider has six. Two are in the front, and there are two more on each side of its head.

Where do brown recluse spiders live?

Brown recluses are found mostly in the Midwest and the South. The spider favors indoor spaces, such as attics, garages, or dark closets. In particular, they settle in old furniture, cardboard boxes, shoes, empty spaces between walls, and wood framing. Outdoors, it hides in out-of-the-way places — under logs, beneath porches, or within piles of rocks.

Females make flat webs to catch food, but male spiders go out to hunt. Brown recluse spiders are nocturnal, which means they’re active at nighttime.