These spiders get their common name from the popular belief that the female eats the male after mating a phenomenon which rarely happens in nature. The genus Latrodectus is worldwide in distribution with 4 species occurring in the United State. Recognition of the genus is sufficient for PCO purpose.
Adult female body length about 12-13mm including an almost spherical abdomen about 1/2"-3/8" (7.2-9.6 mm) in diameter with overall length including legs of about 1 1/2"-1 3/8" (38-43 mm): males about half female size.
Initially the second instar spiderlings remain near the sac but within a few days they climb to a high point within suitable air currents spin silk threads and float out on the breeze like kites. This ballooning provides for general dispersal of the species. Outside black widows commonly live among and under stones and pieces of wood in hollow stumps and trees in rodent burrows and less often in low tree branches or shrubbery. Favorite places are dry man-made structures including barns outhouses henhouses sheds meter boxes brick veneer barrels and woodpiles.