madasyernan's picture

House Spider (Tegenaria domestica)

Observed: 9th December 2009 By: madasyernanmadasyernan’s reputation in Invertebrates
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A tentative guess as to what kind of spider this maybe and an even more nervous guess as to the species.

Species interactions

No interactions present.


Jonathan's picture

I think you are right about

I think you are right about the genus and it is a male because of the large palps, but could it be T. gigantea rather than T.domestica? The latter is paler than your specimen according to my book. THe sternum pattern also fits T.gigantea.

Is it just me, or is this spider at a '70s disco, with its front and hind legs stretched out like that? I'd swear its going 'Y-M-C-A'. Maybe a candidate for the iSpot Xmas caption competition?

University of Edinburgh and Biodiversity Observatory (OU)

Martin Harvey's picture


You're spot on with this being a house spider in genus Tegenaria, but despite their size these spiders are very hard to confirm to species level. The abdominal patterns are variable, and you really need to have a specimen under a microscope (and even then it's down to some quite subtle differences in the structure of the genitalia!). It's possible to do this with live specimens if they can be held still under a microscope, see my attempt at this:

The 'sternum' that Jonathan refers to is on the underside of the thorax, and although the pattern on the sternum can be helpful in narrowing down the possibilities I don't think it is conclusive proof of species.

The British Arachnological Society currently has 9 species of Tegenaria on its checklist. Of these, five are associated with buildings and are reasonably widespread, see:

Given your location I think the most likely choices are T. domestica, T. saeva or T. gigantea, but I can't be sure of that.

Entomologist and biological recorder

Tuisku's picture

They run fast!

I saw a couple of these in my place in the autumn, wandering around and looking for a mate. When I went to identify it, I found some interesting trivia: it has had a Guinnes World Record on being the fastest spider (until 1987). So if you see one, no worth running, just stay still and play dead and it will walk away.

Here is the entry (assuming it is T.gigantea)

Dick_Jones's picture

All the T. domestica I've

All the T. domestica I've ever seen (around 4!) have been rather pale. The adults are very much smaller than those of T. gigantea (hence the name!) and T. atrica which is just as big.
However, I don't think this one is a male; the female palps tend to look slightly enlarged when the tips are seen from this angle; also the legs would be much longer in the male of any of the species.
A pity our most frequently met spider is so difficult to ID! A reminder that the Earth was not designed solely for H. sapiens!