How To Identify Common Jacksonville Spiders And Tell If They're Dangerous

All spiders have venom and fangs. But, as you're probably aware, not all spiders will bite you. Some have fangs that are too weak to break through human skin. You also know that some spiders can bite you but that they'll only leave a red, itchy welt. This is because these spiders don't have a venom that is strong enough to cause you any harm. In fact, you may have more of a reaction from their saliva than you do from their venom. Most of the spiders you'll run into are not going to present much of a threat, particularly if you find them inside your Jacksonville home. The spiders that commonly inhabit human dwellings are spiders that survive on tiny insects. They don't tend to have strong venom. There are two exceptions. Let's take a closer look at how this works.  

brown recluse spider on a wall

Two Spiders To Watch Out For

While there are a few spiders that can cause painful bites, only two are considered a medical threat. This is to say, you could find yourself running to the hospital if you're bitten by one. You probably already know their names. They are widow spiders and recluse spiders. There are several species of each, but they all present the same basic threat to human health within their categories. Widows spiders, both black and brown, have potent venom that can cause severe flu-like symptoms. The venom of a recluse spider can cause spreading necrosis and result in a disfiguring wound. Of the two, only brown recluse spiders prefer to be indoor spiders. This makes them more of a concern.

The Good News

Before we get into identification, it is important to point out that no one in the United States has died from a black widow bite in the United States in over ten years. While it can certainly be unpleasant to get bitten by a widow spider, and it is a pretty good idea to seek medical attention, you need not live in fear. You should also know that widows sometimes cause a dry bite. While painful, it won't lead to flu-like symptoms because no venom is injected into the wound.

Brown recluse spiders are also misunderstood. Over 80 percent of brown recluse bites do not lead to spreading necrosis. They'll only result in an ulcer or lesion at the center of the wound. Along with this, brown recluse spiders are not predisposed to bite humans. Most necrotic spider bites blamed on brown recluse spiders are yellow sac spider bites—or not even spider bites at all.


It can be easy to recognize one of these spiders when you see it. But, in certain circumstances, it can be difficult. We can't help you with the difficult because it's, well—difficult. Juvenile spiders do not look like the adults, and male spiders do not look like the females. There is also a variety of appearances based on species. We're going to focus on the primary, adult female characteristics.

Black Widow Spiders — These spiders are shiny black with a red hourglass marking on the bottom of the abdomen.

Brown Widow Spiders — These spiders are shiny brown with an orangish-red hourglass marking on the bottom of the abdomen. 

Brown Recluse Spiders — These spiders have a brown coloration with a dark brown violin marking on the back, just below the head. 


You may not see dangerous spiders when they establish themselves in your yard or in your home. It is good to know what their webs look like. This can give you advance warning.

Widow Webs — The web of a widow spider has strong, tangled strands that make a sound when you snap them. You'll find these webs in low locations. They're also likely to be in exterior areas where there is dampness or high humidity. Widow webs are not pretty to look at.

Recluse Webs — The web of a recluse spider is very tangled and the threads are thin. You'll find them low to the floor inside your home, or in front of a dark hole or hiding place. Outside, you're likely to see this webbing around a ground hole or in sheltered locations.

How To Prevent Bites From Dangerous Spiders

There are many ways you can reduce your chances of one of these spiders biting you in your Jacksonville yard, or inside your home, but the best way to prevent a bite is to get rid of them and deter them from returning. This can be done by investing in year-round pest control for your property. Dangerous spiders are far from the only harmful pests we have in Jacksonville. No family should be without an effective pest control plan. Let our team help set you up with one. Reach out to Lindsey Pest Services today for spider control and year-round pest control service. We'll help you find the right solutions for your pest concerns.


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