Black widows are identified by red hourglass marking on the underside of their abdomens. Black widows are shiny black in color. Most black widow spiders’ bodies are 3 to 10 mm in size. Females are larger than males and can measure 13 mm in body length. These spiders are members of the genus Latrodectus.
An important characteristic of the black widow spider is its comb foot. This row of strong, curved bristles is located upon the hind pair of legs and is used to pitch silk over captured prey. Black widows are shy in nature. They are solitary, socializing only during copulation. Black widows are nocturnal and spin webs during daytime. They can sometimes be seen hanging upside down in their web, exposing a telltale hourglass abdominal marking. This marking is bright red and signals danger to predators and attackers. Black widows are the largest of web-spinning spiders.
The black widow contributes to the balance of the ecosystem by consuming insects such as flies and mosquitoes. It also controls crop pest populations, feeding on pests that defoliate plants, including locusts, grasshoppers, beetles and caterpillars.