Spider identify

Asked November 2, 2016, 10:16 AM EDT

My friends daughter lives in Idaho and she sent me these pictures, can you identify what spider it is. I do not believe it's a brown recluse. I have included the actual text message I got with the picture, plus I did a screenshot of it a little larger so hopefully we can better identify it But obviously her mother is quite upset until we can know what it is.

Florida

3 Responses

Thank you for your question. Unfortunately, the text message you attached didn't make it through. The spider in your photograph is definitely not a brown recluse (Loxosceles reclusa).

Without having the spider to examine and compare to an identification key, it's can be very difficult to determine a positive identification. I'm checking with some other contacts to get their opinion, and I'll be back in touch as soon as I get some additional information.

Jim

Pretty sure it is a Hobo Spider,
we went into the U of Idaho and compared pics. We knew it was not a brown recluse.

Hello again. I sent your photos to Rod Crawford, who curates the Arachnid collection at the Burke Museum in Seattle. Based on what he can make out on the eye arrangement of your spider, he said it's "probably a hobo spider." Again, you really need to have the spider in-hand to examine it under magnification to be more sure of the identification. According to Rod, the hobo spider (Eratigena agrestis) is very common in Idaho.

At one time, hobo spiders were considered to pose a significant health risk to humans, and their bites were thought to result in necrotic, slow-healing wounds. More recent research has found this is not the case, and their bites are no longer considered to pose a medically significant risk to people, unless you just happen to be overly sensitive to their venom in much the same way that a small percentage of people are allergic to bee stings.

Here are some links that provide additional information, including information furnished by Rod, that may reassure the folks who found the spider:

Insects in the City - Texas A&M University:
http://insectsinthecity.blogspot.com/2015/09/one-less-pest-to-worry-about.html

Barrier Pest Control interview with Rod Crawford:
http://barrierpestcontrol.com/hobo-spider-q-a-with-rod-crawford/

Hope this information helps, and thank you for contacting Ask an Expert.

Jim