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The Spider Myths Site
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House Spider Myths

Myth: Those large, hairy spiders I find in my house are wolf spiders.

Thumbnail of wolf spider Thumnail of giant house spider with 10 cm ruler
Wolf spider
Pardosa vancouveri
    (from a photo by
            Rod Crawford)
Click image to enlarge
Giant house spider
Tegenaria gigantea
  (from a photo by
         Chad Marsh)
Click image to enlarge

Fact: Many people have heard the term "wolf spider" but very few know what it really means. There is a natural tendency to equate "wolf" with "big and hairy." However, true wolf spiders (species of the family Lycosidae) are placed in that family by the arrangement of their eyes, and not by general appearance.

Most wolf spider species are relatively small, their bodies around 1 centimeter long or less. What's more, in North America no member of the wolf spider family is part of the house spider fauna. Evidently their type of prey capture (active pursuit) works better outdoors.

Large, conspicuously hairy, active spiders found indoors are most often males of the European House Spider group (genus Tegenaria). Incidentally, North American wolf spiders are not dangerous to humans.

Myth: Spiders in the home are a danger to children and pets.

Fact: House spiders prey on insects and other small creatures. They are not bloodsuckers, and have no reason to bite a human or any other animal too large for them to eat. In any interaction between spiders and larger creatures like humans, the spiders are almost always the ones to suffer. It is so rare for spiders to bite humans that in a 30-year career of handling tens of thousands of live spiders, I personally have been bitten twice. Both bites had only trivial effects.

A person who is not an arachnologist would not likely be bitten more than once or twice in a lifetime. ("Mystery bites" which people thoughtlessly blame on spiders, don't count! There are no invisible spiders...).

Very, very few spider species have venom that can harm humans, dogs, or cats. In most parts of the world, no spiders with medically significant venom have much chance of being found in houses. In the few areas that are an exception to this rule, the harmless house spider species still greatly outnumber the more toxic ones. And spiders whose venom happens to be more toxic to us, are no more likely to bite us on that account; they are unaware of our existence.

Why, why do people waste their time worrying about spiders? It is not spiders that are dangerous to your children; the dangerous ones are other humans!



Text © 2003, Burke Museum of Natural History & Culture,
University of Washington, Box 353010, Seattle, WA 98195, USA
Phone: 206-543-5590
Photos © as credited
Queries to Spider Myths author, Rod Crawford

This page last updated 2 September, 2010

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