KENNEWICK -- Things have slowed down a bit, so in the spirit of the upcoming haunting holiday, I thought I'd take the opportunity to interview a hobo spider.
I must admit that meeting with this rather large and hairy arachnid was a bit disconcerting, but garden journalists like me are willing to forge ahead in the face of danger.
Mr. Hobo Spider, you used to be known as the Aggressive House Spider, but then you changed your name. How come?
A: Actually I was misnamed the "Agressive House Spider" because uninformed people translated my scientific name, Tegenaria agrestis, to mean "aggressive." A correct translation of my Latin name means "mat weaver of the fields." I was given the name of "hobo spider" by Rebecca J. Vest who worked with her husband Darwin Vest, the researcher who performed the original research on me and my reportedly poisonous bite. Despite this earlier defamation of my character, I am not an aggressive spider!
Q: Why hobo spider?
A: You'd have to ask Rebecca, but I suspect it's because my family is reported to have migrated here from Western Europe through the Port of Seattle sometime before the Great Depression, most likely hitchhiking as egg cases on cargo from the rural areas of Europe. In Europe, my family tends to only be found outdoors in the fields, not indoors or close to homes. I'm now found in Washington, Oregon, Idaho, Utah, Wyoming, Montana and Colorado. I'm often encountered around the foundations of homes and beneath objects in the garden and landscape. I'm also found inside Tri-City homes in late summer.
Q: Why come inside if you aren't aggressive?
A: Late summer to early fall is mating time for hobo spiders. As a male, I search far and wide for a female mate and that includes coming indoors.
You have a rather large family. How many types of you are there?
You're right, my family, Agelenidae, known as the funnel-web weaver family is large. There are more than 500 species of funnel-web weavers around the world with 300 species in North America. We make a web that resembles a funnel.
Q: Do you all look alike?
A: Some of us are quite similar in appearance, especially my closer cousins in the Tegenaria genus. I'm embarrassed to admit that experts have to compare our genitalia to tell us apart. If you want to know more, you can go to this link to determine the difference between me and other look-a-like spiders: PLS 116 at www.puyallup.wsu.edu/plantclinic/resources/pls-res.html.
Q: You are reported to cause a bite that resembles that of a brown recluse. Is this true?
A: For years now, we hobo spiders have been blamed for biting humans and causing a necrotic wound with our venom. Our bites are supposedly similar to those caused by the bite of the brown recluse spider. However, the brown recluse doesn't reside anywhere in the Northwest. A recent research study of the venom of both U.S, and European Tegenaria agrestis showed that neither of our venoms causes skin lesions in rabbits, contrary to a much earlier study of our U.S. venom.
A review of medical literature reveals that there is only one verified hobo spider bite case that caused a necrotic skin lesion in a patient. There is doubt that my bite was the cause in this case because the patient also had a pre-existing medical condition that could have caused the lesion. So at this point, it's unclear if my bite causes necrotic skin lesions in humans or not.
Q: If not, what or who do researchers think might be responsible for such skin lesions?
A: It could be one of the insects that commonly bite humans for their blood. This includes ticks, fleas, bed bugs and others. There are also medical conditions that can cause similar necrotic wounds, such as a Staphylococcus bacterial skin infection or Lyme disease. I don't like to be blamed for something that's not my fault.
I wouldn't either.Thank you for your time.
* Marianne C. Ophardt is a horticulturist for the Washington State University Benton County Extension Office.