Most other spiders, if they are able to penetrate the skin, produce only a mild reaction varying from none, to that of a mosquito bite or wasp sting, unless the individual has an allergy to that particular venom. Consult a physician if pain and discomfort follow a spider bite. The only dangerously venomous spider known to occur in Washington is the western black widow, Latrodoctus hesperus . It is not native to Snohomish County, though it is common in eastern Washington. Specimens are sometimes introduced here but apparently cannot establish a permanent population in our climate.
Widows are shy, retiring spiders and bite only reluctantly, usually only when molested.
A common local house species is often mistaken for a black widow but has no red mark. The much feared brown recluse spider, Loxosceles reclusa is not known to be established anywhere west of the Rocky mountains. Occasional news reports of bites by brown recluse spiders have never been verified with an actual spider specimen. More common in the Puget Sound Area is Tegenaria agrestis, the aggressive house spider. This spider is so named as it bites with little provocation when cornered or threatened.