How to Identify a Brown Recluse Spider

When it comes to poisonous spiders, people in North America have it pretty easy. No redbacks, brown widows or funnel web spiders roam the attics and bedrooms, and there are no tarantulas to fuel arachnophobic nightmares – unless someone happens to be keeping one as a pet. Two venomous species native to North America do occasionally send people to the hospital, although few of these people actually die. The black widow is responsible for about four deaths a year and the brown recluse probably isn't responsible for any. That isn't to say the brown recluse isn't dangerous. It is.

Brown recluse spider, Arizona, America, USA
credit: DeepDesertPhoto/RooM/GettyImages
How to Identify a Brown Recluse Spider

Is the Brown Recluse Deadly?

Some deaths have been attributed to brown recluse bites, but none of these has ever been proven. That doesn't mean the brown recluse (Loxosceles reclusa) is benign. Its bite, although not particularly painful at first, can cause necrosis that may require surgery. In very rare cases, it can result in coma or death, particularly if the bite recipient is very young or very old. But according to spider expert Richard S. Vetter, that has never happened. Still, the brown recluse is a spider to be avoided, although it feels the same way about humans.

True to its name, this spider is shy and non-aggressive. It isn't easy to come across one, especially if you don't live in its native habitat. However, you should know how to identify a brown recluse spider just in case you do happen to spot one hiding in a corner somewhere.

What Does the Brown Recluse Look Like?

The brown recluse is a small arachnid with a total body length – not including the legs – of less than half an inch. The legs are uniformly light in color, with no stripes or bands, and the body is a uniform light-to-somewhat dark brown. The most distinctive marking a violin shape on the cephalothorax, which is the part of the body attached to the legs. The neck of the violin points toward the abdomen and away from the head. Because of this feature, the brown recluse is also known as the fiddleback spider. Juvenile spiders often haven't developed this feature yet and have to be identified primarily by color.

There is one more distinguishing feature, although you'll need a microscope to see it. Instead of eight eyes arranged in pairs, as most spiders have, the brown recluse has only six. These are also arranged in pairs, with a pair on either side of the head and one pair in the middle, just above the mandibles.

The Likelihood of Encountering a Brown Recluse

The habitat of the brown recluse is the southeastern portion of the United States, from the Gulf Coast to as far north as Missouri and from Texas to the western border of South Carolina. The spiders can hitch rides to other parts of the country in fruit crates and luggage, but that is rare. In other parts of the United States, it's more common to misidentify a wolf spider or another species of Loxosceles, such as Loxosceles deserta, than it is to actually encounter a brown recluse.

Within its natural habitat, the brown recluse is most likely to be found hiding in crevices, in basements or behind furniture. The best way to avoid encountering one is to keep clutter to a minimum. If you find a spider you suspect is a brown recluse, consider consulting a spider identification chart online for verification.