Black Widow Spider:

Not all adult female black widows exhibit the red hourglass on their abdomen—some may have a pair of red spots or have no marking at all. Adult male black widows are a quarter the size of the female, and are usually gray or brown rather than black and red; while they may sometimes have an hourglass marking on their abdomen, it is usually yellow or white, not red. The female black widow’s venom is particularly harmful to humans. Black widows build their webs in sheltered, dimly lit places such as garages and sheds.

Wolf Spider:

Some wolf spiders build burrows which can be opened or have a trapdoor, but most are wanderers without permanent homes. Wolf spiders will inject venom freely if continually provoked. Symptoms of their venomous bite include swelling, mild pain and itching. Wolf spiders are nocturnal so they hunt during the evening.

Brown Recluse Spider:

These spiders usually have markings on their dorsal side with a black line coming from it that looks like a violin with the neck of the violin pointing to the rear of the spider. They frequently build their webs in woodpiles and sheds, closets, garages, cellars and other places that are dry and generally undisturbed. Many human victims of brown recluse bites report having been bitten after putting on clothes that had not recently been worn or were lying undisturbed on the floor. The initial brown recluse bite frequently is not felt and may not be immediately painful, yet such a bite can be serious
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