BLACK WIDOW

any member of a genus (Latrodectus) of spiders of the family Theridiidae (order Araneida), especially the species L. mactans. Other species, found around the world, are known variously as widow spiders, or black widow spiders, or by other names. About six species are known. All are venomous, but their bite is rarely fatal to humans. Latrodectus geometricus is found in Africa; L. curacaviensis in the Americas; L. hystrix, L. dahli, and L. pallidus in southern Europe, northern Africa, and southwestern Asia; and L. mactans in most warm areas of the world. L. mactans, L. curacaviensis, and L. geometricus are found in the United States. In the northern part of its range, L. mactans is found most often in trash and near dwellings; L. curacaviensis lives under logs and stones and in woods and fields. In the southeastern United States L. curacaviensis lives in trees and shrubs above the ground; L. mactans lives on the ground. The female of L. mactans, the most common North American species, is shiny black, usually with a reddish hourglass-shaped design on the underside of the spherical abdomen. Sometimes two small spots, instead of an hourglass, are present. The body is about 2.5 centimetres (1 inch) long. The male, seldom seen because it is often killed and eaten by the female after mating, is about one fourth the size of the female. In addition to the hourglass design the male often has four pairs of reddish stripes on the sides of the abdomen. The large web of black widows has a funnel-shaped centre. The female may lay several masses of eggs during one summer. The egg case, suspended in the web, is white or tan, papery in texture, and up to 12 millimetres (1/2 inch) in diameter. It contains 250750 eggs. The young spiders, which are orange and white, emerge in 14 to 30 days. Females may live for more than 1 1/2 years. Like most spiders, the black widow preys on insects. It makes small punctures in the victim's body and sucks the liquid contents. It, in turn, is attacked by mud-dauber wasps and other insect parasites and predators. The bite of the black widow often produces severe pain, nausea, and mild paralysis of the diaphragm. Most bite victims, however, recover without serious complications.