Scorpions are members of the arthropod subgroup Chelicerata, which means their primary food-handling appendages are chelicerae, and their secondary food handling appendages are pedipalps. The pedipalps are the large, claw-like appendages that are at the front of the body, visible in the photograph. Scorpions (like spiders) have four pairs of "walking legs" posterior to the pedipalps, which are also visible above. Scorpions of course also have a sting at the posterior end of the body which is asssociated with a venom gland, and which is used in prey capture (and predator avoidance). If scorpions are potentially harmful, why do they not have warning coloration like Argiope and bumblebees (among many other animals)?

One possibility is that they are nocturnal, so that color would be useless because it cannot be seen in the dark. But if they are nocturnal, how can they be good predators (which they are)? They certainly don't have keen eyesight like owls or other nocturnal vertebrates, nor do they use echolocation like bats. The answer is that they have sense organs in the feet that can detect substrate-borne vibrations caused by prey (such as crickets or other small insects) walking on the ground surface. The vibrations are transmitted from the ground into the exoskeleton of the scorpion, where the sense organs detect deformation of the exoskeleton. Each of the eight walking legs is equipped with a set of these sense organs (called the lyriform organ because its form resembles a lyre), so as vibrations pass under the hunting scorpion, they strike one leg first, then the others. The scorpion can detect temporal differences between lyriform organs of the eight legs as small as a few milliseconds, which allows the scorpion to detect the direction toward the prey. The scorpion turns until the prey is in front of it, then it rushes forward with the pedipalps at the ready, and grasps and stings whatever it catches. Scorpions' lyriform organs are sensitive enough to detect the vibrations caused by a cricket at a distance of up to 30 cm.