Xiphosurida

• Limulidae
• Austrolimulidae
• Belinuridae
• Paleolimulidae
• Rolfeiidae
• Valloisella
• Tri-spine horseshoe crab Tachypleus tridentatus

  A coastal animal of East and Southeast Asia with a hard shell and long tail. It lays eggs on sandy shores, and young animals grow on tidal flats.