Latrodectus is a genus of spider, which contains 32 recognized species. The common name, widow spiders, is sometimes applied to members of the genus due to a behavior seen in some species in which the female eats the male after mating.
The black widow spider is perhaps the best-known member of the Latrodectus genus. Its bite is dangerous because of the neurotoxin latrotoxin which causes the condition latrodectism, both named for the genus. The female black widow has unusually large venom glands and its bite is particularly harmful to humans; however, Latrodectus bites rarely kill humans if proper medical treatment is provided.
The prevalence of sexual cannibalism in female Latrodectus has inspired the common name black widow spider. The females frequently eat their male Latrodectus partners after mating. The female’s venom is at least three times more potent than that of the males making a male’s self defense bite ineffective.
