Black Widow Spider

Quick Overview

Size: 1.5” x .5-.6” 

Characteristics 

The Black widow spider, or Latrodectus spp, is best known for its dark coloration, black hair, and distinctive red hourglass pattern on the back. It is highly venomous with a neurotic venom that acts quickly on specific nerve cells.

Habitat 

It can be found all around the world in both rural and urban areas. These spiders nest near the ground in dark, undisturbed areas with different species inhabiting different continents and countries (including the United States, much of Europe Oceania, and more).  

Behavior 

Black widow spiders are known for being shy and reclusive. They spin their webs in dark, undisturbed areas like holes and woodpiles, not biting unless they are disturbed or threatened. 

What does a black widow spider look like?

A black widow spider has a round body that is a deep, shiny black in color. It is easiest to identify by the bright red hourglass found on the underside of the belly. Sometimes, black widow spiders also have pale red or white spots on their backs or abdomens. 

What is the habitat of a black widow spider in Florida?

In Florida, black widow spiders tend to live in quiet, dark areas that are likely to be mostly undisturbed. That might include piles of wood or rocks or even beneath patio furniture. These spiders can also be found in places like outdoor sheds, garages, and even playground equipment. 

Sometimes black widow spiders prefer to live in holes that were produced by other small animals or insects. You might find them under furniture or desks indoors or even in undisturbed basement areas and crawl spaces. Their nests are loosely formed, looking like mesh. 

What are the behaviors of a black widow spider?

Black widow spiders are reclusive, shy creatures. They aren’t ordinarily aggressive, something that might surprise you given their venomous nature. Black widows only bite when provoked – usually, when they’re pinched or squeezed. 

These spiders build webs and will remain in those webs for most of their lives, with males traveling to females to mate. These spiders usually hang upside down in the center of the web, waiting for their prey to come to them. 

How dangerous is a black widow spider?

Although they aren’t aggressive, black widow spiders are nonetheless quite dangerous. Most of the time, people are bitten when they accidentally brush their hand against the spider or attempt to pick it up. 

Within about 20 minutes to half an hour of being bitten, symptoms begin. These can include stiffness, pain, chills, nausea, and fever. The bites aren’t usually fatal, but they can be extremely painful and lead to anaphylactic shock in some people. 

What should I do if I’m bitten by a black widow spider?

If you’re bitten by a black widow spider, seek medical attention immediately. While you’re awaiting medical help, put a cold washcloth or an ice pack (wrapped in cloth) on the area that was bitten. You can take an over-the-counter pain reliever, like acetaminophen, to relieve the pain, but you should elevate the bite if possible to relieve swelling. 

In some cases, it may also make sense to apply an antibiotic lotion or cream to the bite to prevent secondary infection. Again, it’s important to consult a doctor for full treatment.

Taxonomy:

Kingdom: Animalia

Subkingdom: Bilateria

Infrakingdom: Protostomia 

Superphylum: Ecdysozoa

Phylum: Arthropoda

Subphylum: Chelicerata

Class: Arachnida

Order: Araneae

Family: Theridiidae

Genus & species: Latrodectus mactans

Black Widow Spider Facts and Myths

1. Myth: Female spiders always eat the male after mating. 

Although this is where the name “widow” comes from in the name “black widow spider,” it’s actually not true. Males are seldom eaten by the females, instead lingering near the female for the rest of its life and eating the prey that she captures in her web. 

2. Fact: Black widow spiders are usually found outdoors.

While there’s a chance that you might stumble upon an errant black widow spider indoors, these spiders prefer to hang out in their natural environment. 

3. Myth: A bite from a black widow is comparable to that of a rattlesnake. 

Again, also a myth. It is true that black widow spider venom is about 15 times as toxic as that of the prairie rattlesnake, but black widow bites aren’t nearly as dangerous because a smaller amount of toxin is injected. 

4. Fact: Black widow spiders are more aggressive when protecting their eggs.

This one’s true! Although these spiders aren’t normally aggressive, they might be more aggressive when they feel as though their young are being threatened. 

5: Myth: Only adult female black widows have toxic venom; both juveniles and males are harmless.

Only females can bite and inject venom, but young spiders still have poisonous venom and can be equally toxic in some cases. 

Photo credit: Ken-ichi Ueda, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons