The brown widow is an introduced species while the other three are native to Florida. Its color is usually medium brown although some of them may be dark brown or light brown. It is highly timid and it rarely bites. Nevertheless, the brown widow reproduces quite rapidly and this can create quite a problem since they can spread around one’s home in a very short period. Unlike the black widow, it is less inclined to inject large amounts of venom into its victim, although its venom is twice as potent. This is why anyone with a poor immune system should be careful when it comes to the brown widow spider.