Since most solifugids are nocturnal, the reason for calling them sunspiders or sunscorpions (another common name) is not obvious.
These creatures are commonly called windscorpions because they can run so fast although I have never seen them run. With their large chelicerae (front jaws) windscorpions look very fierce. They can inflict a painful bite with these but they have no venom glands. Windscorpions are predators, sometimes even feeding on small lizards.
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