How to Tell If a Spider Is Poisonous

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Can you tell if a spider is poisonous just by looking at it? Unfortunately, no, there aren’t any markings or physical features that can tell you that. The best way to know if a spider is poisonous is to learn which spiders in your area are poisonous and how to correctly identify them. So, what poisonous spiders are in the southeastern United States? 

Keep reading and we’ll show you, so you can know how to tell if a spider you’re looking at is poisonous. 

Which Spiders in the Southeast are Poisonous?

Let’s backtrack for a second. No spider is poisonous – because “poisonous” isn’t the right word. Instead, they’re “venomous.” People sometimes use these two words interchangeably because whether you’ve been poisoned or envenomated, the outcome is similar: you feel sick. However, for the sake of accuracy, let’s note that spiders are not poisonous – they’re venomous.

Not sure about the difference between “poisonous” and “venomous”? Here’s a simple way to look at it:

• Venomous: You may start feeling sick if something that’s venomous bites or stings you. Examples include various species of spiders and snakes.
• Poisonous: You may start feeling sick if you eat something that’s poisonous. Examples include poisonous mushrooms and berries.

Which Spiders in the Southeast are Venomous?

Now that we’ve gone over the difference between poisonous and venomous, let’s talk about these potentially harmful spiders in our region. 

It’s estimated there are more than one thousand spider species in the United States – and the vast majority are not venomous. However, we do have some harmful spiders in the southeast that can be very dangerous to have around your home. The bites of these spiders can cause severe reactions and may even require hospitalization. The three most common are brown recluses, black widows, and hobo spiders.

Brown Recluse Spider

Most brown recluse bites are accidental. For example, many people get bit after a brown recluse wanders into some clothing or towels, and then is pressed against the skin. Brown recluses are not aggressive, but they may bite if they feel threatened.

These bites may appear minor at first, but the pain will rapidly increase over several hours. Some people describe the pain as unbearable, and you may also feel sick – like you’ve been poisoned – with fever, body aches, and chills. The bite mark will have a light-colored center with purple or blue around it and a red perimeter. The venom injected into the skin from a brown recluse bite can cause the skin around the bite to die and create an open wound that can take months to heal.

Brown Recluse Characteristics:

• Tan to dark brown coloring
• Has a violin-shaped marking on its back to its head
• Approximately ¼” – ½” long
• Semicircle pattern of three pairs of eyes

Should you seek medical attention for a brown recluse bite? Monitor your condition closely. Seek immediate medical attention if the pain becomes severe or you experience breathing difficulty, chest pain, or other serious symptoms.

Black Widow Spider

Black widows look fearsome, but they are not aggressive. Like brown recluses, they usually only bite when they feel threatened. When you picture a black widow, it’s most likely the female you’re picturing – males are much smaller and do not have the red hourglass marking. Females also have the venom that causes painful reactions in people – males do not.

Symptoms of a black widow bite include nausea, chills, sweating, swelling, pain, and abdominal cramping. 

• Shiny black coloring on almost its entire body
• Red hourglass shape on the abdomen. May also have white or red spots on the abdomen.
• Approximately 1 ½” – 1 ⅜” long
• Eight eyes

Should you seek medical attention for a black widow bite? Monitor your symptoms closely. If pain, chills, nausea, or abdominal cramping become severe, seek immediate medical attention.

Hobo Spider

Hobo spiders are easily mistaken for brown recluse spiders because of their similar size and coloring. This has led to a debate on how dangerous these spiders actually are to humans.

Hobo spider bite symptoms are fairly minor. Usually, it’s some redness, pain, and swelling. However, because hobo spiders are easily mistaken for brown recluses and vice-versa, it’s important to closely monitor your symptoms.

• Light to medium brown blended coloring
• One dark line between two lighter lines on its head with a yellow and gray pattern on its abdomen
• Approximately 1” – 1 ¾” long
• Eight eyes in two straight rows

Should you seek medical attention for a hobo spider bite? If it was a hobo spider bite and not a brown recluse, you probably don’t need medical attention. However, if you feel like you’re experiencing significant symptoms or an allergic reaction, seek immediate medical attention.

Keep Your Home Safe from “Poisonous” Spiders

You never want to allow a harmful spider infestation to grow out of control. These “poisonous spiders” – or, to be more accurate, venomous spiders – can pose hazards to you and your family. 

Rocket Pest Control’s spider exterminators can quickly locate any spider infestation and eliminate it so you have peace of mind. Contact us today for a free quote to keep your home a safe place to be!