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I find these in forests in Oregon, western half, though they're probably on the eastern half as well. They live under pieces of wood and bark, and have a small web across the ground. Mine will eat crickets, but I think they eat carpenter ants, termites, and maybe pillbugs/sowbugs. It seems about an inch long, red on the thorax and legs, and dark grey and slightly hairy on the abdomen. The closest to this spider I've found is sowbug killers -- they're in my backyard, but they're smaller then this spider and also are a light tan on a hairless abdomen, with lighter colored legs. The fangs also seem different shapes but I'm not sure about that.

Spider 1 Spider 2 Spider 3 Spider 4

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  • $\begingroup$ Thanks for getting the images up there, I still can't figure out how to do it. Is there a way on mobile? $\endgroup$ – Tzacol Dec 27 '13 at 23:36
  • $\begingroup$ There is on iPhone at least, I'm not sure on other platforms. You can always type up the markup manually (though it is a little cumbersome on mobile): ![an image](http://example.com/image) $\endgroup$ – Rory M Dec 27 '13 at 23:57
  • $\begingroup$ I thought it was the woodlouse spider too which is why I posted an answer but I am unsure now since you already suggested it. It should belong to the genus Dysdera though $\endgroup$ – The Last Word May 28 '14 at 5:52
  • $\begingroup$ Oregon has over 500 spiders so its hard to identify which one this is $\endgroup$ – Sonic Splasher Apr 21 '18 at 20:06
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This is very likely a species in the Amaurobiidae superfamily, and I agree appears to be Callobius severus (the hackled-band weaver or the hackledmesh weaver).

enter image description here

Source: Bugguide.net

enter image description here

Source: Kyron Basu 2012

Moldenke et al. 1987 provide a key to spiders of the Pacific Northwest. Importantly, they note:

adult genitalia are necessary for identifying species and separating Callobius from Amaurobius.

  • For example, here is a picture of Amaurobius ferox (Hackledmesh Weaver)

    Amaurobius ferox

    © Danny Steaven 2008

  • I've seen numerous sites conflate this species with C severus and actually I've seen sources that identify them both as the "Hackledmesh Weaver".

So although the OP's specimen strongly resembles Callobius severus, a scope is necessary to truly identify to species. This Penn State page provides good information regarding these similar looking species in the superfamily.

Callobius and Amaurobius species have similar life histories and behaviors. They are most often found in damp locations under bark, leaf litter, and stones, as well as in woodpiles and other protected areas.

Stephen Ellis Lew (2011) produced an atlas to the genitalic morphology of the Callobius genus, and he proposed a morphological diagnosis that is more consistent with principles of homology than those previously in use. [See the link for his dissertaiton on the subject].

Callobius severus

Description:

  • Cephalothorax and legs = reddish to dark brown [Source].
  • Abdomen = dark to light grey with fine hairs; often with large, bilaterally mirrored paler spots.

Ecology:

  • Nesting woodland species commonly seen in the Pacific Northwest

  • McIver et al. (1990) suggests that this species of spider is one of many that is characteristic of young forests.

Is it Dangerous?:

  • Not according to this Penn state website:

    The one verified record of a bite by an immature Callobius species resulted in pain, itching, swelling, redness, and nausea.

  • Vetter & Antonelli provide evidence for how to differentiate this species from the "more dangerous" hobo spider.

    enter image description here

    in the side view, the palp of Callobius males has large, conspicuous, pointed projections (Fig. 7).

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It look like Callobius severus to me.

enter image description here

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