The name "black widow" comes from a behavior of some species in which the female eats the male after mating. Contrary to popular believe, the female black widow rarely eats the male after mating, although it is true that the female's bite is three times are more venomous than the male's bite.
The female black widow is black with an hourglass mark on its abdomen. This mark can range in color from a deep red to yellow. Although the female is about half inch long, the male is only about half the size of its female counterpart. The males are usually brown or gray and sometimes do not have the red colored mark on the abdomen.