Flat rock scorpion (Hadogenes troglodytes) scurrying across rocks. This is one of the largest species of scorpion in the world and can reach 20 centimeters in length. It is indigenous to Africa. Scorpions are arachnids and belong to the arthropod phylum. They possess eight legs, a pair of claws, and a venomous sting at the end of their abdomen.