Neuroscience For Kids

Brown Widow Spiders Arrive in Louisiana
May 11, 2007

Scientists at the Louisiana State University Agriculture Center (LSU AgCenter) are warning people in Louisiana to be on the lookout for a new, potentially dangerous invader: the brown widow spider (Latrodectus geometricus). The brown widow spider is a close relative of the more well-known black widow spider (Latrodectus mactans).

The brown widow spider apparently has traveled from Florida to Louisiana. Both the brown widow spider and black widow spider are venomous and kill their prey using a neurotoxin. The neurotoxin (latrotoxin) causes a massive release of the neurotransmitter called acetylcholine.

According to experts at the LSU AgCenter, brown widow spiders can be found in brush piles, crawl spaces, and under chairs, flower pots, eaves and porch railing. However, brown widow spiders are shy, less likely to bite and deliver less venom in their bites than black widow spiders.

Did you know?

• A black widow spider bite usually first feels like a pinprick and then causes swelling. A few hours after a bite, a person may feel pain and stiffness and have chills, fever, nausea and stomach pain. However, these spider bites are rarely deadly.
• No one in the United States has died of a black widow spider bite in the last 10 years. (Source: California Poison Control System)
• According to the National Institutes of Health, a person bitten by a black widow spider should seek immediate emergency medical treatment and then "wrap ice in a washcloth or similar material and place it on the bite area. Leave it on for 10 minutes and then off for 10 minutes. Repeat this process."
• The scientific name of the black widow spider, Latrodectus mactans comes from a mixture of Latin and Greek words, meaning "deadly biting robber." (Source: Rohou, A., Nield, J., and Ushkaryov, Y.A., Insecticidal toxins from black widow spider venom, Toxicon, 49:531–549, 2007.) The brown widow spider, Latrodectus geometricus, comes from words meaning "geometric biting robber."

References and more information:

1. Expert Says Louisianans Should Watch Out For Brown Widow Spiders - LSU AgCenter Press Release
2. Brown Widow Spiders
3. Neurotoxins - Neuroscience for Kids
4. The Synapse - Neuroscience for Kids

Copyright © 1996-2007, Eric H. Chudler, University of Washington