Ancient scorpion (Pterygotus) emerged in the mid period of the Paleozoic, approximately 400 million years ago.
Unlike the scorpion in general, simpler forms of ancient scorpions. His body consists of many segments of the thin shell protected. Another difference is the size of the bodies of some ancient scorpion species that reached 100 times the present size of the scorpion, 2 to 3 meters. In addition, ancient scorpions also live in the water.
Living Pterygotus contemporaneous with ancient sharks. He has a jagged claw for capturing mangsanya.seperti mentioned Pterygotus body length can reach 2 meters. Although invertebrates, Pterygotus have a hard outer frame.
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