Spider Identification

[Robin Leech]

Hi Lynn,

Funny that someone from Washington would send the picture abroad when the
guys who know about it are right next door.

The spider is Family Agelenidae, species: Tegenaria agrestis, female.
Common name: Hobo spider.  The specific epithet means "rural" or "agrarian"
or "of the country".

Though this species has been implicated in cases of necrotic lesions after a
bite, no consistency has been observed.  Thus, if 10 spiders of this species
bit 10 different people, there would be no problem. However, the 11th bite
may cause necrotic lesions.

We are not sure of the cause or causes.  It could be that the 11th spider
had bacteria on its fangs, or it could be that in the first 10 bites the
spiders did not emit venom, and that the 11th did.  The venom itself is
essentially the same that for others of the genus Tegenaria.  All I can
advise is use caution when dealing with any unfamiliar spider.

There are two other species of Tegenaria, both imports from Europe, in the
Washington and British Columbia area: Tegenaria domestica (cosmopolitan);
and Tegenaria duellica (a junior synonym name is Tegenaria gigantea).
Tegenaria domestica is called the house spider, and with legs spread is
rarely much larger than 25 mm.  Members of the species Tegenaria duellica
can often have a leg span over 10 cm, and move very swiftly.

I am "Bcc"ing a copy to my friend Robb Bennett of Victoria, BC (I am in
Edmonton, Alberta).  This is one of Robb's specialties.

Robin Leech

----- Original Message -----
From: "Lynn Raw" <lynn.raw at VIRGIN.NET>
To: <TAXACOM at USOBI.ORG>
Sent: Saturday, June 14, 2003 1:57 AM
Subject: Spider Identification


> I have been sent a photograph of a spider from North America (WA, USA). It
> was found inside a house by someone who is concerned that it could be a
> danger to her chameleons or even perhaps herself.
>
> The photograph can be viewed at www.afriherp.org/spider.htm
>
> It may be possible to get more photographs if necessary.
>
> Any assistance will be much appreciated.
>
> Lynn Raw
> London, UK