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How to identify (or misidentify) the hobo spider Rick Vetter 1 and Art Antonelli 2
Since the late 1980s, many people in Washington have been concerned about the hobo spider because it has been blamed as the cause of dermatologic wounds. We offer here a guide to help identify some medium-sized Washington spiders found in homes. However, keep in mind that without a microscope you may not be able to identify hobo spiders and may have to settle for determining that your spider is NOT a hobo spider. This may be frustrating and not the goal you had in mind, however, quite often the question is not "What spider do I have?" but "Do I have a hobo spider?" You should be able to learn enough to eliminate many spiders from consideration without a microscope and sometimes with just the naked eye. Most people want a world with simple black/white answers but you must realize that there many shades of gray in between and this is the reality of spider identification. This publication was initiated because there is no currently available guide to spider identification for the person with limited arachnological skills. Most of the previous guides for hobo spider identification try to give a simplistic way to discern hobo spiders. We have found that many well- intentioned people misconstrue the information and confidently misidentify their non-hobo spider as a hobo. The other references actually are reliable if you already know something about spider identification similar to the fact that a dictionary is a book that helps you spell words if you already know how to spell words. However, the misidentification of harmless spiders as hobo spiders can result in inappropriate anxiety and/or the unnecessary spraying of insecticides to kill off spider populations which are actually beneficial species
show you that the answers are not easy to obtain but if you are interested in taking your discriminatory skills up a notch, with a little practice, you should be able to confidently determine the characteristics of spiders that are NOT hobo spiders, which will be the majority of the medium-sized spiders you will encounter.
because of the insects they eat. What this publication tries to do is Fig. 1 Hobo spider Photo by P. K. Visscher © 1 Dept. Entomology, Univ. Calif. Riverside, CA 92521 2 Extension Specialist, Wash. St. Univ., Puyallup, WA 98371
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A general warning Most non-arachnologists try to use coloration as a diagnostic identifying feature. This is one of the least reliable characteristics for identification of hobo spiders because of the great variation amongst specimens within a species and because similar species sometimes overlap in their appearance with hobos. If you try to identify them by size, you will also be mistaken because the variation is tremendous. Many other species look the same to the non-arachnologist who lumps them all together as hobo spiders and often is wrong. If you continue to try to determine spiders with...