1, horseshoe crabs are chelicerates, very primitive. The horseshoe crab worm is a species of crustaceans in the cuttlefish subclass. It can be said that the two are not related at all, only because they look more like so enjoy the seemingly the same name.

2, Chinese horseshoe crab dioecious, female body than male body. Produced in Xiamen coastal area of horseshoe crabs, generally female body cephalothorax armor length of about 40 centimeters, weighing about 4 kilograms of male body length of about 30 centimeters, weighing about 2 kilograms. External morphology by the cephalothorax (anterior body part) and abdomen (posterior body part), before and after the two body parts of the back are compounded with hard armor (respectively known as thoracic and abdominal armor), the back of its convex, ventral for the concave.