What this spider has going for it is a really scary name. Otherwise, you probably wouldn’t hear much about it. It rarely kills people and many who are bitten never even know it. There are 32 types of widow spiders, including the western, southern, and northern widows, as well as the red, gray, and brown widows. They’re found on every continent except Antarctica. The females are usually dark-colored, frequently with red, white, or brown markings on the dorsal of the abdomen. Some have the classic hourglass-shaped markings and some do not. Black widows are usually small but carry an unusually potent venom that contains larotoxin, a neurotoxin that can cause pain, muscle rigidity, vomiting, and sweating. Symptoms typically last three to seven days. Only the female bite is considered dangerous to humans. Each year, about 2,200 people report being bitten by black widows. None has died since 1983. On the other hand, some house cats have died of convulsions or paralysis.