How to Identify Louisiana Spiders

Brown Widow

There are many different types of spiders living in the southern regions of the United States, and some are even native to Louisiana. Some of them are poisonous, some of them are harmless and some of them help to keep the number of insect pests living around our houses low. However, if you get a visit from one of these eight-legged guardians, it is important to know how to identify different types of spiders so that we can tell which ones are dangerous and which ones can be calmly moved outside.

Instructions

1. Judge how large the spider is by looking at the length of its body and the length of its legs.

2. Check to see if the spider has a body that is one inch or more in length without including the leg span. If it does, then the spider is most likely a golden silk spider, dark fishing spider or a black and yellow garden spider. If the spider has a body that is less than one inch long without including the leg span, then you should skip to Step 6.

3. 

   Check the spider's web, if it has one. If the web has a golden-yellow color to it and the spider is yellow and black with red bands across its legs, then it is most likely a golden silk spider. These spiders are also referred to as "banana spiders" and their bite is poisonous enough to cause blistering and redness.

4. 

   Estimate how long the spider's leg span is. If the leg span is around three inches long, and the spider is a dark brown color with light and dark gray markings, then it could be a dark fishing spider. These spiders enjoy living near water or dark, damp places. They can run across water to hunt for prey, they do not maintain a web and they are just poisonous enough to cause minor redness and necrosis near their bites.

5. 

   Check to see if the leg span of the spider is about 2 1/2 inches long, and look for yellow and black markings with a white area near the head. If your spider fits this description, it is likely to be a black and yellow garden spider. Bites result in only mild itching and swelling for a couple days, though it is believed their bites could inject a very small amount of neurotoxin as well.

6. Do not attempt to measure the leg span for smaller spiders. It is much easier to tell these spiders apart by looking for distinct traits or markings. In Louisiana, these spiders could be brown recluse spiders, Hentz’s orbweavers, bold jumping spiders, black widows or brown widows.

7. 

   Check to see if the spider is brown and smooth with a violin-shaped pattern on its back. If it fits this description, then the spider is most likely a brown recluse spider. These spiders are very poisonous and aggressive, and they enjoy hiding in soft places like the arms and legs of clothing, bedding, or pillows more than any other spider in Louisiana.

8. If the spider has a leg span of about an inch and a half long with a very round body, then the spider is most likely a Hentz's orbweaver spider. It is easier to tell when these spiders are around, because they weave huge webs up to six feet in diameter to catch flying insects outside. These spiders are not toxic to humans.

9. 

   Look carefully at the spider to see if it is black with a white marking on its back. Also, if the spider is jumping around this is another big sign that the spider you are looking at is a bold jumping spider. These spiders are aggressive and spunky, with a bite that hurts but lacks any dangerous poison.

10. 

    Look at the coloration of the spider and see if it is black with a red hourglass-shaped pattern on its underbelly. If it is, then it is almost certainly a black widow. These spiders have extremely poisonous venom, and commonly hang upside down from their rough, messy webs.

11. 

    Check to see if the coloration of the spider is brown with yellow-orange dots on its back and a yellow-orange hourglass shape on its underbelly. If it is, then the spider you are looking at is a brown widow. These spiders have even more toxic venom than their black widow relatives, but they inject less of it in their bites. All the same, keep your distance.

12. If none of these steps led you to an identification of the spider in question, try sending a picture to a biologist in the area, or contact a poison control center if bitten. You may also try an online resource, such as the one listed under additional resources below this article.

Tips & Warnings

• Spider identification is tricky business if you squish your eight-legged visitor. Try to avoid pounding a spider to death if you would like to know what it was later.

• Always seek medical attention if bitten by a poisonous spider. Serious symptoms may not start appearing for as long as eight hours after the initial bite. If you can, try to catch the spider that bit you so that you can present it to medical officials for identification.

Resources

• Helpful database to look up spider information