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Black Widow

The Southern black widow spider is distributed from southern New England to Florida west to eastern Oklahoma, Texas and Kansas. They are more common in the southern part of their geographical range, hence their name "southern black widow". The jet black color, rounded abdomen, and red hourglass marking on abdomen is distinctive for this spider. Adult spiders average 1.5 inches long. The female black widow spider is the one usually seen, as the male is often eaten by the female after mating. The widow spiders characteristically spin tangled webs, which look similar to spun cotton candy. Their webs are usually built in or beneath objects close to the ground such as under porches, under foundations of buildings, the lose bark of trees, and in basements. The bite of the black widow is painful and may cause death if medical attention is not sought immediately. The venom of this spider is highly neurotoxic and respiratory failure can occur if appropriate medications are not administered at once. Fortunately, the black widow is shy and does not bite without great provocation. The spider normally resides in a coarse, irregular web. The adult female spider will bite if she feels her young are threatened.

Brown Recluse

A brown recluse has a dark brown violin shape on the cephalothorax (the portion of the body to which the legs attach). The neck of the violin points backward toward the abdomen. However, what you should look at instead is the eye pattern of 6 eyes in pairs with a space separating the pairs. Most spiders have 8 eyes in two rows of four. The brown recluse spider's bite is necrotizing and the site of the bite is very slow to heal.

Aggressive House Spider

Aggressive house spider (Tegenaria agrestis) is common in the PNW in and around houses, barns and sheds. It is a member of the funnel-web spider group. This is a relatively large spider (body size, excluding legs 3/8" - 5/8"; 1" - 1-3/4" including legs) with long, hairy legs and chevron-shaped abdominal markings. The venom is necrotic, causing open, localized wounds that may be slow to heal. Males may be more venomous than females and become quite common in mid-summer through the fall during the mating season. Despite its aggressive nature, however, reported bites from this spider are relatively rare. There are several closely related species that look very similar but whose venom is not as toxic.





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