Hobo Spider Identification Project
by Rick Vetter, M.S.
If you think you have a hobo spider, I am willing to identify it for you!!!!!
The hobo spider, Tegenaria agrestis, (top photo left) is a native of Europe and has been implicated as a medically important spider since 1987. It is found from British Columbia to southern Oregon and west to mid-Montana, western Wyoming and northern Utah. It has not yet been verified in California.
The black widow is easily identifiable by its shiny black body and ventral red hourglass and to a lesser extent the brown recluse is identifiable by its pattern of 6 eyes yet many harmless spiders throughout the U.S. are often misidentified as recluses by overzealous non-arachnologists including medical personnel. In contrast, the hobo spider is a large, generic looking brown spider that is easily mistaken for other large brown spiders such as wolf spiders, amaurobiid spiders and closely related funnel web spiders. In addition, in the Pacific Northwest, the gigantic house spider is a species in the same genus as the hobo spider, and looks very similar (top right photo: hobo spider on left, gigantic house spider on right). Also throughout the U.S., another closely related but smaller spider, the domestic house spider, Tegenaria domestica, is commonly found and to a lesser extent in California through Texas, Tegenaria pagana sometimes shows up. To confuse the matter even more, there are dozens of additional funnel weaving spiders, mostly in the genera Agelenopsis and Hololena that are mistaken for hobos.
Although it is sometimes possible to identify a hobo spider from its coloration, this takes lots of practice and experience with dozens of determined spiders before one can be accurate. The only way to be 100% sure you have a hobo spider is to compare its genitalia to the original scientific drawings because these structures are specific to each species whereas coloration can vary greatly within one species and overlap with several other species.
Therefore, I am willing to identify for you any spider that you think is a hobo spider. Currently I am coordinating a massive distribution study involving 8 states and British Columbia. I would appreciate as much data as possible from as many places as possible. This project should finish around March 2002. Do not send photos over the internet as you probably will not be able to photograph the salient features that will allow me to identify it for sure.
If you would like to send a spider to me for examination, you must follow the directions below because you cannot legally mail live spiders to me unless you already live in California and you should not mail flammable liquids like alcohol unless you follow the severely strict regulations.
Kill the spider by freezing or if you have smashed it, just take it in the smashed form. Even though you may think a smashed spider is useless, I will be able to find the necessary anatomical features necessary for species identification
Either 1) preserve the spider in alcohol for a week and on the day of shipping, pour off the alcohol and send the spider damp inside a small vial or 2) let the spider air-dry for a few days in order that it doesn't rot and smell up the package on the trip to southern California. Pack the spiders in a small container so that they don't get crushed in the mail. Some people just drop a spider in a baggie and mail it. The resultant splooge, nicely preserved in between plastic for me to see, is disgusting.
Part of my study, you will need to supply me with the following information for each spider unless they were all collected in the same city on the same date:
1. State
2. County
3. City/town
4. Date of collection
5. Your email address, LEGIBLY WRITTEN in block letters or regular postal address
Send it to
Rick Vetter
Hobo ID project
Entomology
Univ. Calif. Riverside
Riverside, CA 92521
I will respond to you with the identification of your spider if it is a hobo spider or related one as soon as I get it. Send as many as you wish to have identified because in places where they have the gigantic house spider, the hobo spider still does exist but at a lower frequency so if you only send one or two, that doesn't mean that you don't have hobo spiders.