Florida is home to 59 different species of arachnid. Many of the spiders are not dangerous, however, there are venomous species. This article lists the 6 most venomous spiders in Florida, describing what they look like, where they live, and how dangerous they are.
Most Venomous Spider in Florida
1. Red Widow
Credit: Florida Division of Plant Industry by CC 3.0
Scientific Name: Latrodectus bishop
The red widow spider is identified by its red-orange cephalothorax and legs. Its abdomen is jet black and adorned with vibrant red spots, which are outlined in bright yellow.
Widow spiders got their name due to the fact females often kill and consume their male mate after copulation.
Where Will They Be Hiding?
The red widow is endemic to Central and South Florida. They are restricted to terrestrial areas of dry sand dunes with plenty of sand pine.
Most of this spider’s life is spent hidden among short palmetto bushes, where they make their webs.
Red widows actively avoid human contact, and due to their limited habitat range, you are unlikely to find one near your home.
Are They Dangerous?
Like all true widows, the red widow is venomous. Their jaws are strong enough to puncture human skin. The bite itself is similar to a sharp pinprick, followed by a numbing pain surrounding the wounded area. Cramping, nausea, muscle aches, and mild diaphragm paralysis can occur.
A rather small amount of venom is injected through red widow bites, meaning the likelihood of death as a result is rare. Very young children, the elderly, and the vulnerable are at the most risk.
Red widows tend to avoid humans and are not known to be aggressive toward them. In medical literature, there have been no recorded bites by this species of spider.
Venomous Spiders in Florida Identification
2. Southern Black Widow
Credit: Steve Jurvetson by CC 2.0
Scientific Name: Latrodectus mactans
The Southern black widow is glossy, jet black in color. They are distinguished by their characteristics, bright red hourglass shape that is located on the underside of the globular abdomen.
Females often have a small, red patch just above the spinnerets on the abdomen.
Where Will They Be Hiding?
The Southern widow spider is indigenous to the Southeast United States. Typically, they build their webs in low-lying areas that are well hidden. Habitats include log and rock piles, rodent burrows and sheds, garages, and basements.
Are They Dangerous?
The strong fangs of black widows can easily puncture human skin, sometimes leaving puncture marks. Mature females have larger jaws than males and can inject much higher amounts of venom.
The venom of black widows is neurotoxic. It can inhibit the normal functioning of the nervous system.
The bitten area often becomes red and swollen. Symptoms include muscle cramping, nausea, headaches, sweating, and stomach pain.
In healthy people, fatalities from Southern black widow bites are extremely rare. There are over two thousand reported black widow bites every year in the United States. Over the past several decades, there have been no recorded fatalities from black widows.
Antivenom can be issued but is rarely provided unless necessary. The symptoms should go away on their own after a few days.
3. Northern Black Widow
Credit: Judy Gallagher by CC 2.0
Scientific Name: Latrodectus variolus
The Northern black widow spider is glossy, and jet black overall. The iconic red hourglass marking on the underside of a black widow’s abdomen is split in the middle. Northern widows also have a series of red spots along the dorsal midline of their abdomen. Additionally, they often have multiple, horizontal white lines running along their abdomen.
Where Will They Be Hiding?
The Northern black widow is found throughout the Eastern United States, from Southern Canada to South Florida. They inhabit crevices and gaps in old logs, brush piles, abandoned animal burrows, and corners of outbuildings.
Are They Dangerous?
Black widow’s venom is 15 times for toxic than that of a rattlesnake.
Only a small amount of venom is injected by widows, but it can still cause nasty effects. Neurotoxic venom affects the functioning of the central nervous system. Pain, muscle spasms, and vomiting are some of the symptoms.
Although there are over two thousand reported black widow bites per year in America, there is a less than 1% mortality rate. The deaths are mainly in very young children.
4. Brown Widow
Credit: JMK by CC 4.0
Scientific Name: Latrodectus geometricus
Brown widow spiders range from tan to dark brown in color and their legs have black stripes. The dorsal side of their abdomen is covered with geometric brown patterns. The underside of their abdomen boasts the iconic hourglass shape, but it is vivid orange or yellow in color.
The brown widow is also called the brown button spider, house button spider, and geometric button spider.
Where Will They Be Hiding?
The brown widow has a very large geographical range. Native to Africa, they are now found across the Americas, Eurasia, and Australia.
Brown widows build their webs in dark and protected areas and are common residents in urban environments, including houses. They inhabit woody vegetation, dark corners, storage closets, mailboxes, and virtually any suitable crevice they can find.
Are They Dangerous?
Some scientists believe brown widow venom is just as toxic as black widow venom, but they inject much less so the damage is not as severe.
Symptoms of a brown widow bite include muscle pain and discomfort around the wounded area. No bite victims have shown symptoms of responses to neurotoxins.
5. Brown Recluse
Scientific Name: Loxosceles reclusa
Brown recluse spiders range from tan to dark brown in color. They have a black or dark brown pattern on their cephalothorax that resembles the shape of a violin. Due to this, they are also called fiddle back spiders, brown fiddlers, and violin spiders.
Where Will They Be Hiding?
The brown recluse spider is distributed mainly throughout Southeast America, from Texas to Georgia. When outside, these spiders inhabit debris and woodpiles. Brown recluse spiders are often found in houses. They make their home in cardboard because it mimics rotting tree bark.
Clothing, shoes, bedding, and storage areas also make great habitats for this species. Often, hundreds or thousands of them can be found in a single area, meaning infestations are not uncommon.
Are They Dangerous?
The brown recluse, as its name suggests, is not an aggressive species. However, their bite can be dangerous and medical attention should be sought. Their venomous bite causes necrotic (rotting) skin lesions. In rare cases, hemolysis can occur.
Hundreds of brown recluse bites are reported every year in America. Children, the elderly, and the seriously ill are at the most risk. There have been no documented fatalities as a result of a brown recluse bite.
6. Chilean Recluse
Credit: Sergiosan by CC 3.0
Scientific Name: Loxosceles laeta
Like other recluse spiders, the Chilean recluse is brown overall with a dark patch on its dorsal thorax that resembles a violin. It is a fairly large species, reaching 40mm in size.
Where Will They Be Hiding?
The Chilean recluse spider is native to South America. They build irregular webs in woodpiles and outbuildings such as sheds and garages. They commonly frequent human habituates areas and can be found in clothing, bedding, and under furniture.
Are They Dangerous?
The venom possessed by a Chilean recluse is more potent than that of a brown recluse. They have a necrotic bite, meaning the skin and surrounding tissues of the bite form a large, open sore. This can take months to heal and leaves deep scars. Fatalities are rare but can occur.
Common House Spiders Native to Florida
- Wolf Spiders
- Spiny-Backed Orb Weavers
- Southern House Spiders
- Cellar Spiders
- Banana Spiders
- Yellow Garden Spiders
- Daddy Long Legs Spiders
- Jumping Spiders
Symptoms of Envenomation
Envenomation is the induction of poison by a living organism, in this case, a spider. Visible signs of envenomation are puncture marks as a result of the bite as well as redness, swelling, bruising, blistering, or bleeding around the wounded area.
Systemic symptoms include pain around the bite wound, nausea, vomiting, diarrhea, difficulty breathing, increased heart rate, perspiration, muscle cramps, and numbness.
First Aid for Spider Bite Victims
For spider bites, there are a few first-aid measures that can be taken. Firstly, the wound should be thoroughly cleaned, and ice should be applied to the wound to reduce pain and swelling. Antibiotics should be applied during the healing process to help prevent infection. If the bite is serious, antivenom can be issued by a doctor.
Venomous or Poisonous?
Something that can be referred to as poisonous is the toxin enters your body through inhalation, swallowing, or absorption. The term venomous is used when the toxin is injected into the body.
If you bite it and you die, it’s poisonous. If it bites you and you die, it’s venomous.
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