Black widow spiders are known for their striking appearance and their tendency to eat their mates, as well as their unique and striking appearance. The most venomous spiders in North America are not always fatal to humans.
Male and female black widows look different from each other. The females of black widow species have shiny black bodies and a red marking on the underside of their round abdomen. The female's mark on the hourglass can be orange-yellow.
The University of California's Division of Agriculture and Natural Resources says that males are lighter in color with smaller abdomens that may have red or pink markings. Black widows have a body length of up to 13 millimeter, and males are typically half the size of females.
Where do black widows live?
Latrodectus spiders are found in a number of regions around the world, including North America, southern Europe and Asia, Australia, Africa and much of South America. Black widows are found mostly in the South and West of the United States.
What do black widows eat?
A venomous black widow spider is native to Arizona. Steven Love has a stock photo.
The black widow eats arthropods that get caught in their webs. According to the Burke Museum of Natural History and Culture in Seattle, Washington, females do not usually eat their mates.
The only Latrodectus species that mate cannibalism in nature is the rule, not the exception, and most black widow males "survive to mate another day," according to the museum. The Nature Conservancy of Canada says that black widow newborns eat their siblings as they emerge from their eggs.
Black widows eat insects and arachnids, but they can also trap and eat small animals such as snakes and lizards. The Department of Entomology at Iowa State University says that after the spider releases its food, it carries it away to be eaten.
How many black widow species are there?
The spider was found in the leaves of a maple tree. The image was taken by NajaShots.
Black widows are the only species of widow spiders in the Latrodectus genera. The western, Latrodectus hesperus, the northern, Latrodectus variolus, and the southern, Latrodectus mactans, are the three North American spider species.
"Black widow spiders are members of the family Theridiidae, which is also known as comb-footed spiders, because they have a series of stiff, short hairs on the last segment of their fourth pair of legs that resemble a spider," Sewlal said. This is used to drape the silk over the prey.
The Latrodectus genus has red and brown widows.
Kingdom: Animalia.
Bilateria is a subkingdom.
Protostomia is a part of the kingdom.
Superphylum: ecdysozoa.
The phylum is called the Arthropoda.
The subphylum is called Chelicerata.
Arachnida is a class.
Araneae.
Theridiidae is a family.
Latrodectus is a Genus.
ITIS is the source.
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How do black widows reproduce?
A spider is spinning an egg. The Biology Department of the University of California, Riverside has this image.
Black widows are mostly solitary, with the exception of late spring when they are in love. Males that are ready to mate begin by spinning silk that they soak with sperm and then wrap around appendages called palps near their heads. Live Science previously reported that when they find a receptive female, they insert their sperm-coated palps into her reproductive opening.
The female creates papery egg sacs that may contain hundreds of eggs, which hatch after about 30 days. Spiderlings are pale yellow after hatching and live for 180 days, while males mature after 70 days and then live for another 30 days, according to ISU.
According to the University of Michigan's Animal Diversity Web, the Latrodectus mactans black widows can live up to four years in captivity.
The black widow's bite is toxic.
Female black widows are more likely to bite people than males. Black widow venom is 15 times stronger than a rattlesnake's, but because spiders deliver less venom than snakes, their bites are a serious risk only to the very young and the very old.
"Bites from this spider are very rare," said Sewlal.
The black widow's bite feels like a pinprick to most people, but it's caused by a chemical called alpha-latrotoxin that quickly overwhelms nerve cells, causing swelling and intense pain.
The effects of a bite by a member of this group can include nausea, sweating, pain in the abdomen and back, muscle aches, hypertension and paralysis of the diaphragm, which can cause difficulty in breathing.
According to the Occupational Safety and Health Administration, pain can last for up to 12 hours. Black widow antivenom is available to help minimize damage, and the antivenom is effective for bites from all black widow species, and pain is usually gone within 30 minutes.
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