Introduction to horseshoe crab: The official Chinese name of horseshoe crab is horseshoe crab. It does not belong to crabs but is a member of the family Limulus. This is a very ancient animal that has lived on the earth for 400 million years, so it is called a "living fossil" animal. Horseshoe crabs look a little scary, but they actually do not pose any danger to people. The horseshoe crab does look very strange, with its mouth in the center of the abdomen and its eyes at the front of the hard shell. The most incredible thing is that the gills used for breathing grow on the last pair of feet. Female horseshoe crabs are larger than males. When it's time to lay eggs, the mother digs a hole in the sand with her body, then lays thousands of eggs waiting for the father to fertilize them. When it was all over, they returned to the water.