Western Black Widow
Near the ground beneath ledges, rocks, plants, and different types of debris
Warmer regions of the United States including all four deserts (Great Basin, Mojave, Chihuahuan, and Sonoran)
No listed status
This species is
to the Truckee Meadows.
Western black widows are venomous spiders most recognizable by the females' black bodies with red markings, sometimes in the shape of an hourglass. Western black widows are sexually dimorphic, meaning that males and females appear different. Males are brown or gray and feature a small red spot on their abdomens instead of an hourglass. Males and females also differ in size, with females being 1.5 inches long and males only half that size. Western black widow webs aren't built in any specific shape or form, often looking erratic. These spiders build their webs in dark, secluded places close to the ground such as log stacks and drain pipes.
There are three black widow species that can be found in the United States: southern black widows (Latrodectus mactans), northern black widows (Latrodectus variolus), and western black widows (Latrodectus hesperus).
Black widow webs are sticky in order to trap other insect prey in their webs. The spiders produce a type of oil on their legs which prevents them from getting stuck.
These spiders are known as black widows as females sometimes ingest the males after mating.
Black widows inject their prey with digestive enzymes that liquefy the prey and allow them to drink up their dinner.
National Geographic, Black Widow Spiders, 2021, https://www.nationalgeographic.com/animals/invertebrates/group/black-widow-spiders/
Animal Diversity Web, Latrodectus hesperus, 2001, https://animaldiversity.org/accounts/Latrodectus_hesperus/
Image: Konrad Summers, https://www.flickr.com/photos/tkksummers/2800388371, license https://creativecommons.org/licenses/by-sa/2.0/, cropped from original.
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