Black Widow Spider (Latrodectus)

Black Widow Spider (Latrodectus)

What is Black Spider Widow? Latrodectus genus of spider get common name due to belief that female spider eats the male after mating. And this phenomenon which rarely happens in nature. This spider most recognized for the red hourglass shape in abdomen. A black widow’s venom reported to be 15 times stronger than a rattlesnake’s (one of the most venomous spiders in North America). It may cause muscle ache, nausea and also make breathing difficult.

Kingdom Animalia
Phylum Arthropoda
Class Arachnida
Oder Araneae
Family Theridiidae
Genus  Latrodectus
Common Location North America

Common Name – Black Widow Spider

Diet – Carnivore

Size – (0.5 to 1.5 inches) 1.3 cm to 3.8 cm

Average lifespan – Up to 3 years

Predators – Wasps, Birds, Other widows.

Color – Black, Red, Brown, Yellow

Skin Type – Shell

Habitat – Woodland, Temperate Forest, Urban

Black Widow Spider

Black widows very numerous in most of the parts of US but cases of reported bites are rare. Both male & female venomous but no reports of bites from male have been recorded.

Female black widow about 1.5 inches long and males about half the size. Female Latrodectus can eat male after mating.

A Latrodectus Hesperus (black widow) known as one of the few species harmful to people in North America. Both male and female black widows look different and different appearance.


Species wise scientific names

  • Red Widow – Latrodectus bishopi
  • Brown Widow Latrodectus geometricus
  • Western Black Widow – L. hesperus
  • Southern Black Widow – L.  mactans
  • Northern Black Widow – L. variolus


Female looks most distinctive with shiny black bodies and red hourglass shaped marking on underside of their round abdomen. While males are lighter in color along with pink to red spots on their back side according to NCSU (North Carolina State University). Widow spiders have eight eyes arranges in two rows of four and vision is quite poor.

Where Black Widows live?

Black Widows or Latrodectus found in temperate zone or mild temperature areas throughout the world including United States, Southern Europe, Asia, Australia, Africa and South America. Reproduction – Black Widow Egg Sac contain lots of egg.

These spiders found in dry and dark shelters like brans, basements, gerages, toilet, hollow stumps, rodent holes, brush, dense vegetation.


Three main species – Northern Black Widow spider, Western Black Widow Spider, Southern Black Widow Spider.

Species Scientific Name
Northern Black Widow Spider Latrodectus variolus
Southern Black Widow Spider Latrodectus mactans
Western Black Widow Spider Latrodectus hesperus

Interesting facts about black widow

Male eater spider – Popular belief that all black widow spider feast upon mates after mating. But species varies in their post coital behavior. In few cases some the male escape in majority of cases. But in some cases they actually allow themselves to be cannibalized.

Liquid diet – Many spiders including Black Widows spin a silk cocoon around prey. When food bundled lectrodactus & other species inject digestive enzymes which responsible or creating bug milkshake of sorts. This type of food easy for spider to eat or digest.


Vile Venom – A black widow’s venom reported to be 15 times stronger than a rattlesnake’s. Black Widow Venom cause various health issues to humans especially to child and who have weaker immune system.

Secluded Abodes – Widow spider prefer to spin it’s web in protected and dark places. These spiders humans only when directly disturbed or harmed. Normally when a person is moving object black widow hide to safe place.

How Black Widow Spider Venom works – Venom acts by destabilization of cell membrane and degranulation of nerve terminals. It resulting releasing of neurotransmitters. Which result muscle spasm and hypertension.

Black Widow Spider Habitat Latrodectus species are reclusive or shy nature. Due to this behavior they tend to spin web in dark area away from light as well as undisturbed area. Widows spider frequently found in woodpile, in holes, under old furniture. Also use space like basements, sheds and attics. 31 known species of widow spiders and different species found at different regions of world.

Widow Spider

Other name black widows – Brown widow spider, False Widow Spider, Brown Recluse spider

Latrodectus or Widow Spider broadly distributed genus of spiders and composed of both Black Spiders and Brown Widow Spiders. They found in temperate regions around the world. Latrodectus also known as most venomous spiders in North America.

Widow Spider Food – Widow spiders prey on various insects like mosquitoes, caterpillars, grasshoppers, flies, beetles.

Latrodectus a member of Theridiidae family and genus contain thirty one species. Black Widow Spiders bites can cause serious health problems including severe pain, abdominal pain, muscle cramping, back pain and others. How to protect from bites – Wear long sleeve shirt, hat, gloves, boot when you handling things like lumber, firewood, handling boxes (outside from houses or during night out). Inspect cloths and shake properly clothes and shoes before getting dressed. Use insect repellents such as picaridin, DEET.

Black Spider Widow

Black Widow Spider Care – Widow spiders are venomous in nature. So should not kept as pets. They does not require huge space, she typically remains in her web once it built. It also require plenty of ventilation and use sticks, branches, pipes, plants and stones. These spiders build web and spent majority of life in their web. These spiders tends to hang upside down in centre of web and waiting of prey. Male spider travel to web of female for mating.

Black Widow bite treatment Clean bite area properly with soap and water. Apply ice on bite area (to slow absorption of venom). If you are a Heart patient you may need hospitalization.

Shape, Size and Body parts – Black Widow Pictures There is size widely varies in female spiders mainly gravid females (egg carrying). The abdomen of such females can be greater than 1/2 inch in diameter. Widow Spider have two main body parts i.e cephalothorax and abdomen. Cephalothorax bears head and legs. Abdomen much larger than Cephalothorax & spinnerets or silk and web making appendages attached to rear part of abdomen. The spinnerets look like a cluster of small cones in widow spiders.