What Are the Most Dangerous Types of Spiders?

Identifying Symptoms of Dangerous Spider Bites

There are more than 43,000 species worldwide. With such a large number you might think spiders are a mighty hazard to humans, but less than 30 have been responsible for human deaths. Effective antivenoms have been developed, but still, on average, 7 people in the United States die each year as a result of a spider bite. Small children, the elderly, and those with a compromised immune system are the most susceptible.

What Is the Most Venomous Spider in the World?

What is the most dangerous type of spider in the world? The Guinness World Record holder for the most venomous spider to humans is the Sydney funnel-web spider. However, unless you are spending time on the east coast and highlands of Australia, you are unlikely to encounter this creature. In North America, the brown recluse is considered the most dangerous spider.

How Many Species of Spiders Are in North Carolina?

There are over 1,500 spider species in North Carolina, and the brown recluse and black widow are among them. While it is wise for everyone to take precautions against the most dangerous types of spiders, keep in mind that though they may be creepy and even scary to some, spiders are an extremely valuable part of our ecosystem. They are vital in taking care of other creepy crawlies by eating 400-800 million metric tons of insects each year!

List of Most Dangerous Spiders

What are the most dangerous types of spiders? Let’s concentrate on spiders that are found in the United States.

Yellow Sac Spider

If you wake up with a spot that is red, itchy, and inflamed, you may have been bitten by a yellow sac spider. Some people do not react to their venom at all, while others have an allergy-like reaction. While yellow sac spiders are not harmful to most if you have a severe allergy they can be dangerous.

Facts About Yellow Sac Spiders

  • Yellow sac spiders like to hide in clothing or laundry, and sometimes bites occur when you put on clothes they are hiding in.
  • Also known as a black-footed spider, black-footed yellow sac spider, or American yellow sac spider, its body is pale in color and is believed to reflect what they have most recently eaten.
  • They can sometimes be identified when their black “feet” are seen against a light-colored surface.


Their size (4.5-11 inches), thick legs and body, and almost mammalian-like hairiness have resulted in tarantulas getting a bad reputation. Their bites can be painful for days, but research indicates that there are no documented deaths by tarantula. There is a report of 2 deaths in a remote part of India, Churulia, but may have been the result of gangrene and rashes that were not treated.

Facts About Tarantulas

  • Tarantulas are mostly found in dry, arid regions of the United States.
  • They primarily eat insects but are known to eat small rodents, reptiles, and amphibians when necessary.
  • Female tarantulas can live up to 30 years, while males have a much shorter average lifespan at about 7 years.

Hobo Spider

Hobo spider bites can be a bit more serious, as their venom has the potential to cause deterioration of body tissue around the bite. Usually, a bite will blister after about 24 hours, then turn dark. These bites can take a long time to heal and may need medical attention. Severe headache, fatigue, and nausea are other symptoms that may follow a hobo spider bite.

Facts About Hobo Spiders

  • This species of arachnid is found primarily in the western United States, with a concentration in the pacific northwest.
  • The hobo spider is about half an inch long with hairy legs and is brownish in color.
  • It will usually have V-shaped markings on its abdomen, much like a chevron pattern, and the mouthparts of the male resemble boxing gloves.

Brown Widow Spider

The brown widow spider’s venom is actually twice as potent as the black widow, but it is not considered quite as dangerous because it does not inject as much venom as the black widow. Brown widow spider bites are painful and may turn red.

Facts About Brown Widow Spiders

  • Similar in body type to the black widow, it is brown in color and the hourglass shape on its back is orange, instead of the red found on a black widow.
  • Brown widows are mostly found in nooks and crannies in the southern U.S., such as under furniture or in boxes in storage areas.

Black Widow Spider

A black widow bite can kill a small animal, such as cats and dogs. In the past, about 5 percent of black widow bites in the U.S. were fatal, but thanks to its antivenin, fatalities are now rare. The bites are still serious though, and may result in:

  • Pain
  • Vomiting
  • Chills
  • Fever
  • Respiratory issues
  • Delirium
  • Muscle spasms
  • Spike in blood pressure
  • Partial paralysis

Facts About Black Widow Spiders

Brown Recluse

The brown recluse is one of the most venomous spiders in the United States. One of the complicating issues with a brown recluse spider bite is that it is usually not felt, so treatment is not even a thought until the venom has already started its destruction.

There is a protein in the brown recluse venom that will cause a dark spot and inflammation at the site of the bite. At-home treatment can work for adults if it is done immediately upon identifying the bite. Small children often cannot fight the toxin, so they should see a medical professional right away.

If the tissue starts to break down from the venom, surgery may be required to cut out the infected area. If left untreated completely, a brown recluse bite can lead to kidney failure, seizures, and even death, although there are no verifiable reports of deaths due to brown recluse bites in North America.

Facts About Brown Recluse Spiders

  • The brown recluse can be found in the southern and central United States.
  • It’s about an inch in length, brown in color, and has a fiddle shape on its back (sometimes called a fiddleback spider).
  • It is also identifiable because it has 6 eyes instead of the usual 8.

They are called a recluse because they keep to themselves. You can try to avoid bites by not sticking your hand, or any other body parts, into areas into which you cannot see.

What Does a Spider Bite Look Like?

When someone asks “What does a spider bite look like?” the answers can vary greatly. Most commonly, spider bites will appear as small red bumps that are itchy. Some may be a little larger in size, particularly if a person is allergic to their venom.

Because spider bites are usually just small red bumps, they are sometimes rashes that are misidentified as spider bites.

Can You Tell What Kind of Spider Bit You by the Bite?

  • A brown recluse bite will usually turn red first, and then turn a dark blue or purple. It will sometimes have a ring around it, and the spider bite will look like a bullseye.
  • Hobo spider bites usually blister and may discharge fluid.
  • A black widow bite may have double fang marks.

If you know you have been bitten by one of these three spiders, very carefully try to catch the spider in case you need to seek medical treatment, but do not risk getting bitten again.

What Symptoms Come from a Spider Bite?

The symptoms that come from a spider bite vary as much as the spiders themselves, and each person’s reaction will be different.

In addition to redness, pain, swelling, burning, and itching, other symptoms that come from a spider bite can include:

  • Abdominal pain/stiffness (black widow)
  • Tissue necrosis
  • Sweating
  • Fever
  • Chills
  • Body Aches
  • Ulcerated skin (brown recluse, black widow, hobo spider)
  • Trouble breathing
  • Headache
  • Vomiting/Nausea
  • General malaise
  • Fatigue
  • Muscle cramps
  • Facial swelling
  • Seizures
  • Coma
  • Jaundice
  • Blood in urine
  • Kidney failure
  • Change in blood pressure (elevated by hobo spider, lowered by tarantula bite)
  • Numbness
  • Restlessness
  • Eyelid puffiness (tarantula)
  • Visual or aural disruption
  • Increased heart rate

Environmentally Friendly Spider Control

Spider control can be a tricky business. Chemicals are not very effective against spiders, so pesticides can merely create an unnecessarily toxic environment. That is just one of the reasons that Sage Pest Control uses environmentally friendly methods for your spider and other pest control needs.

For nearly a decade, our 3 locations in Charlotte, Raleigh, and Greensboro have been serving the pest control needs of their surrounding areas. As a family-run business, we place great importance on supporting our community, and we pride ourselves on the fact that we are one of the few companies that are both QualityPro and GreenPro certified.

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