While spiders specialize in sexual cannibalism, scorpions, their fellow arachnids, seem to just dislike each other. They lead solitary lives, and when they meet, they often fight, kill, and eat each other, as this photo shows. They also sometimes practice sexual cannibalism, if they don't immediately fight to the death.
A study of desert scorpions back in 1980 showed that other scorpions represented only the fourth-most common meal for a scorpion, but by body mass it was number one, representing more than 25 percent of the total.