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Northern Black Widow (Latrodectus variolus)

The Northern Black Widow is a typically North American ‘East Coast’ spider and is the most common in the northern regions of its range. The species is closely related to the southern and the western black widows. The females of the species are sexual predators and live in very strongly-built, typically three-dimensional webs in the wild.

Northern Black Widow

Scientific Classification

Physical Description and Identification

Adults

Size: Adult females are approximately 9-11 mm in length, and the males are 4-5 mm – that is, almost half the size of the former (both excluding legs).

Color: The characteristic hourglass mark in the Northern Black Widow is rather broken (unlike the female Southern Black Widow’s that has the hourglass mark distinct). Males have four diagonal whitish bands on each side of the abdomen.

Other Characteristic Features: Male black widows are not black, but are rather gray or brown with small red spots. Also, the males play their roles only for reproduction purposes and are mostly consumed by the females after mating or copulation.

Northern Black Widow Spider Size

Eggs

The females lay approximately up to 200 eggs that they incubate for around three weeks in a small, round, brown, papery sac that remains attached to the mother’s web.

Northern Black Widow Spider Egg Sac

Spiderlings

Like the males, the juveniles and immature specimens have two pairs of diagonal whitish bands on both sides of the abdomen. After hatching, the baby spiders remain in the cocoon for around four weeks. They are taken care of by the mother until they are matured enough to forage for themselves.

How Poisonous is the Northern Widow Spider

Surprisingly, the bite of these spiders is not frequent since they are actually sky and timid, and usually choose to flee if threatened. Though the toxin of a widow spider is 15 times more potent than the rattlesnakes’, because of the negligible amount of the venom injected through the bite, they are much less serious. In fact, there is as less as 1% mortality rate (usually children) of humans bitten by these creatures. Pain is felt immediately after the bite is inflicted, apart from other symptoms like local redness, and usually increases for 1 to 3 hours, but might last for 24 hours.

Northern Black Widow Spider Range

Quick Facts

Other Names Northern widow
Lifespan 1 to 3 years
Distribution Ranges from northern Florida to south-eastern Canada
Habitat Mostly prefer undisturbed woods, stumps, and stone walls
Common predators Birds of prey, larger spiders
Diet Mostly insectivorous, but might prey upon other smaller spider species and non-insect arthropods as well
Northern Black Widow Male
Northern Black Widow Spider Web

Did You Know

  • These arachnids have been compared to widows mourning in ‘black’ cloak for the unique appearance of the females, and tendency to eat their mates.
Northern Black Widow Spider

Image Credits: I.pinimg.com, Ctvnews.ca, Usaspiders.com, Spiderid.com, Venombyte.com, Media.mnn.com, I2.wp.com

The Northern Black Widow is a typically North American ‘East Coast’ spider and is the most common in the northern regions of its range. The species is closely related to the southern and the western black widows. The females of the species are sexual predators and live in very strongly-built, typically three-dimensional webs in the wild.

Northern Black Widow

Physical Description and Identification

Adults

Size: Adult females are approximately 9-11 mm in length, and the males are 4-5 mm – that is, almost half the size of the former (both excluding legs).

Color: The characteristic hourglass mark in the Northern Black Widow is rather broken (unlike the female Southern Black Widow’s that has the hourglass mark distinct). Males have four diagonal whitish bands on each side of the abdomen.

Other Characteristic Features: Male black widows are not black, but are rather gray or brown with small red spots. Also, the males play their roles only for reproduction purposes and are mostly consumed by the females after mating or copulation.

Northern Black Widow Spider Size

Eggs

The females lay approximately up to 200 eggs that they incubate for around three weeks in a small, round, brown, papery sac that remains attached to the mother’s web.

Northern Black Widow Spider Egg Sac

Spiderlings

Like the males, the juveniles and immature specimens have two pairs of diagonal whitish bands on both sides of the abdomen. After hatching, the baby spiders remain in the cocoon for around four weeks. They are taken care of by the mother until they are matured enough to forage for themselves.

How Poisonous is the Northern Widow Spider

Surprisingly, the bite of these spiders is not frequent since they are actually sky and timid, and usually choose to flee if threatened. Though the toxin of a widow spider is 15 times more potent than the rattlesnakes’, because of the negligible amount of the venom injected through the bite, they are much less serious. In fact, there is as less as 1% mortality rate (usually children) of humans bitten by these creatures. Pain is felt immediately after the bite is inflicted, apart from other symptoms like local redness, and usually increases for 1 to 3 hours, but might last for 24 hours.

Northern Black Widow Spider Range

Quick Facts

Other Names Northern widow
Lifespan 1 to 3 years
Distribution Ranges from northern Florida to south-eastern Canada
Habitat Mostly prefer undisturbed woods, stumps, and stone walls
Common predators Birds of prey, larger spiders
Diet Mostly insectivorous, but might prey upon other smaller spider species and non-insect arthropods as well
Northern Black Widow Male
Northern Black Widow Spider Web

Did You Know

  • These arachnids have been compared to widows mourning in ‘black’ cloak for the unique appearance of the females, and tendency to eat their mates.
Northern Black Widow Spider

Image Credits: I.pinimg.com, Ctvnews.ca, Usaspiders.com, Spiderid.com, Venombyte.com, Media.mnn.com, I2.wp.com

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