Other Common Names
Greater European House Spider
Pronunciation
Téh-juh-NARR-ee-uh jy-GAN-tee-ah
Synonyms and other taxonomic changes
Tegenaria duellica
Size
All measurements are for only the body, and do not include the legs.
Females: approximately 16-18 mm.
Males: smaller, approximately 10-12 mm.
Identification
No banding on the legs, but proportionally longer legs than its cousins T. agrestis or T. domestica.
Range
Tegenaria gigantea is mostly restricted to the Georgia Lowlands / Puget Trough area west of the Coastal (BC) and Cascade (US) mountain ranges from south coastal BC to mid-coastal Oregon. Isolated outlier populations are found in towns across southern BC and in Edmonton (Leech & Steiner 1992) and Lethbridge AB (Dan Johnson and Robb Bennett pers. obs.) and in Saskatoon SK (Buckle & Randell 1995). Although at least on the BC south coast T. gigantea may be very common around beaches and other open, natural areas, populations in the BC interior are apparently always isolated. (Taken from: Internet Link #2, See Internet Reference section below.)
Habitat
In comparing the ranges of the T. gigantea and T. agrestis, T. gigantea is more common in coastal locations and T. agrestis dominating the interior. Anecdotal evidence suggests that, where the two species are sympatric, T. gigantea “out-competes” T. agrestis although the nature of their relationship is unclear. (Link #2, See Internet Reference section below.)
In an unpublished study (1980s) by
Rod Crawford, Curator of Arachnids at the Burke Museum, gigantea was found to outnumber agrestis by about 50 to 1 in Seattle-area house properties that had been occupied largely by agrestis 20 years before.
"Natural" populations found on cliff faces and rocky areas. ~ Rod Crawford
When found around human structures, it is often located in darker areas, such as flower beds, wood piles, and areas where it can weave a funnel-web. When it is found in homes, it often is found in the darker recesses of the basement, such as corners. It is a nocturnal spider, so generally it is discovered when the lights are turned on and the spider darts for cover (and/or its web).
Food
Insects, possibly other spiders
Life Cycle
Life cycle images:
(spiderling, juvenile, molted skin, adult female & male)
Remarks
This spider (like its cousins
T. domestica and
T. agrestis) was imported from Europe into the ports of the Pacific Northwest. The first known N. American record was from Vancouver Island in 1929. It did not reach Seattle until 1960.
The greater European house spider (T. gigantea) is not dangerous to people. Some people may be intimidated by their size as male legspans can reach 4 inches (100 mm). However, Rod Crawford has never known one to bite a human (though they certainly could if they tried); they are so docile he uses them as hands-on demonstrators for school children.
The Hobo Spider (
T. agrestis) is often confused with this spider. If you are unsure of the exact species, just be mindful of this confusion, and use caution when dealing with the spider. (See
T. agrestis for more information about the hobo spider).
The presence of giant house spiders is a deterrent to the establishment of hobo spiders indoors. It out-competes and displaces the hobo spider indoors and male giant house spiders often kill male hobo spiders (without necessarily eating them)!
Explanation on use of T. gigantea vs. duellica:
In 1975, this species was discovered to be distinct from the close European relatives, T. saeva and T. atrica. It was described as new (T. propinqua). In 1976, T. propinqua was compared with the type specimens of T. gigantea (described from an introduced population in Victoria, BC) and found to be the same.
In 1978, the Italian arachnologist Paolo Brignoli, apparently feeling offended that a European species had a North American name, resurrected the long-unused name T. duellica for this species. But there are several things wrong with that conclusion.
1) The original description of duellica is not really good enough to be certain what species it is.
2) The type specimens of duellica cannot be found and therefore its identify cannot be confirmed. This type of uncertain name is known as a "nomen dubium."
3) duellica was described from Spain in 1875. The species gigantea is not known to have spread outside of its native England before the 20th century. So there is good reason to believe that the two actually are not the same, though we'll never know for sure unless the type specimens are found.
There is still no consensus on this issue. Lots of people besides me use the name gigantea. The Platnick online catalogue uses duellica on the grounds, apparently, that any new change must be for the better. Robb Bennett, the Canadian funnel-weaver speciaist, is on the duellica side though he's never said why. I say, why not use an appropriate name that is well-founded on existing type specimens? ~ Rod Crawford
Internet References
1)
zoo.org: A good fact sheet about the Giant House Spider (Greater European House Spider)
2)
Newsletter of the Entomological Society of British Columbia, Volume 22, Number 1 July 2002 (an article by Robb Bennett:
Hyperbole and Hysteria on the Path to Enlightenment – a Review of Current Tegenaria Projects of Relevance to Canadian Arachnologists)
