Behold, the brown recluse!
Brown recluses aren’t often out during the day. Instead they hide, at times inside houses—in an attic, basement or behind a piece of furniture. In South America, the tendency has earned them a nickname: la araña detrás de los cuadros, or “the spider behind the picture.”
The bite of a brown recluse isn’t terribly painful, so why does the spider have such a fearsome reputation? The short answer is: its venom.
Brown recluse venom can cause a deep wound that takes weeks or even months to heal and can produce symptoms like nausea and a fever. If you are unlucky enough to be bitten, hope the culprit was male. A female’s venom can be twice as concentrated as a male’s.
Living things can respond very differently to venoms. Though toxic to humans, guinea pigs and rabbits, brown recluse venom (Loxosceles reclusa) has little effect on mice and rats. Scientists aren’t sure exactly why.
See the brown recluse and 16 other arachnids in Spiders Alive! now open.