About the Black Widow Spider
The female black widow is jet black with a yellow hourglass shape underneath its abdomen. Females are about 40 mm long. Male black widows are actually smaller, have a lighter shade of black, and they lack the hourglass marking. Instead the male has a brown stripe on its back with white or yellow streaks. The black widow is predominantly found throughout the Southern United States. Black widows prefer dimly lit areas like barns, garages, hollowed stumps, outhouses and places with dense vegetation. The female black widow's venom is 15 times more potent than a rattlesnake's, says the integrated pest management program of North Carolina. Male black widows do not bite.
Brown Widow Spider
One spider that resembles the black widow which predators and humans should avoid is the brown widow spider. Its venom is actually more toxic than the black widow's, and it even has a yellow to orange hourglass figure on its abdomen. The Science Daily states that the brown widow is usually found in the tropics, but in the last five years it has become more common in the Southeast United States. The brown widow is brown to tan in color, and it has brown bands on its legs.
False Black Widow Spiders
The false black widow is similar in size to a black widow, but it lacks the red hourglass pattern on its abdomen, says Steven Jacobs Sr. from Penn State University. Their range in the United States is nearly identical. Oddly enough, the brown widow will sometimes kill and eat the more deadly black widow spider. The false black widow's bite may lead to blisters and fatigue for several days, but its venom is nowhere near the toxicity of the black widow's. Jacobs sais care needs to be taken in identifying the species which bites the victim, as sometimes the black widow's anti-venom has needlessly been administered to victims of false black widow bites.
Other Cobweb Spiders
The black widow is part of the cobweb spider family. There are over 200 species of this family found in the United States. Due to the fear that the black widow evokes in humans, many people misidentify the black widow with more common benign members of its family. The American house spider has the same shape as the black widow, but is much lighter in color. It inhabits similar environments where the black widow is found, and sometimes it can be hard to distinguish them in dark garages, barns and outhouses where they both lurk.