How to Identify Spider Types

There are over 50,000 known species of spiders, so being able to identify one particular specimen is a difficult chore. Even experts use microscopes in many instances to examine some of the organs of a spider to identify it correctly. But there are some things a layman can look for in a spider to at least group it into its right family and perhaps identify it accurately. The most important thing that you can purchase to identify different types of spiders is a field guide to spiders with pictures and facts about many species.

Things You'll Need

• Magnifying glass

Instructions

1. Purchase a field guide such as the "National Wildlife Federation Field Guide to Insects and Spiders of North America" by Arthur V. Evans or the "National Audubon Society Field Guide to North American Insects and Spiders" by Lorus Milne.

2. Carefully examine a spider's eyes. The arrangement of the eyes is often a giveaway as to what type of spider it may be. For example, a wolf spider has eight eyes, with one on the left, one on the right, two in the middle of those a little lower and then four in a row below those. You will probably need a magnifying glass to clearly see all of the eyes of most spiders.

3. Note the size of the spider. You can narrow down which type of spider it is simply by looking at how big it is. Observe and record the length of the spider's legs, the length of its abdomen and the overall size of its body to use as an identifying tool.

4. Check for any specific markings on the body of the spider. While many species are one shade of color, there are some with distinctive markings such as the female black widow spider, which has a red hourglass-shaped marking on its lower abdomen, or the yellow garden spider, which has a yellow-and-black back with four white dots in the center.

5. Take into account where you find the spider. The habitat of a spider can help to identify it. If you find the spider in its web, then determine which type of web it is. Webs are constructed in different ways and in different places. The garden spider, for instance, builds an elaborate web in tall grass looking to trap the multitude of insects that live in fields and meadows.

6. Use your field guide to eliminate possible spiders. Field guides come complete with maps that show the range of different types of spiders across the U.S. If you happen to live in the east and a spider that you are trying to identify looks like one that is found only in the western states, then you know it cannot be that type of spider.

Tips & Warnings

• There is no need to kill a spider to identify it. Take a picture of the spider to use for future reference if need be.

Resources

• Read this Article in Spanish
• Burke Museum of Natural History: Spider Myths site