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Which Spiders Are Actually Poisonous?


There are a lot of spiders in the world. A ton more than you might think. In fact, from where you're sitting you could be as close as a few yards from a spider, according to famous arachnologist Norman Platnick. Some scientists and media reporters have stretched this too, "You are never more than three feet from a spider.” While that may not always be true, we think the more important question is, how many of them are poisonous? And how, close are those poisonous spiders to me?

It is believed that there could be between 75,000 and 100,000 species of spiders on the planet. Scientists aren't entirely sure because there are vast areas, like the rain forest, that have not been fully explored. As of this writing, there have been over 34,000 species identified. That is a lot of spiders. And, the news gets worse; all of them are poisonous! What? All of them? Yes. Spiders are a predatory insect and they use their poisons to subdue their prey. But you can relax. The vast majority of spiders have a poison that is only harmful to the creatures they prey upon. In the entire world, only about a dozen species of spider can hurt humans. And of these, only a couple are poisonous spiders found in St. Louis and elsewhere in Missouri and Illinois.

The brown recluse: These spiders are often identified by the fiddle-shaped markings found on their abdomen. The word recluse is the key to understanding this spider. They are reclusive by nature, only leaving their nest to hunt. You are most likely to find it hiding inside a box in the attic or in the back of your garage. However, this frail-looking brown spider is typically not going to attack you. That vast majority of brown recluse bites happen when this spider is brought in contact with the body: putting on a shirt, sliding into bed, slipping into shoes, etc. Their bite is venomous to humans and can cause extreme tissue damage if not treated.

The black widow: These spiders are typically identified by the red/orange hourglass shape on their abdomen. We've all heard of this lady, who is known for eating her mate after he is no longer needed. Despite the rumors, this is rarely the case in most of these species and most often seen in labs where the male is unable to get away. Regardless, their bite is venomous to humans and while, most times, it is not deadly, it is still cause for concern.

How do you avoid these creepy crawlers, you ask? Be vigilant about looking before you put on clothes or shoes or slip into bed. Remove any webbing found in corners of your home. If they re-appear, this could be the sign of a problem. If you see anything suspicious, have an inspection done to determine if you have a problem. You may need to see about scheduling year round pest treatments to help curb any ongoing infestations. Since spiders are predators, the fewer pests you have in and around your house, the less food you'll have for creepy spiders to feed on.

For help getting rid of spiders and other pests in Missouri and Illinois, Rottler Pest & Lawn Solutions is your local pest control company and we are here to help. Contact us today to schedule a free inspection!

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