External structure of crustaceans?

The body of a crayfish has only two sections. The first section is the “cephalothorax”. This section represents the head and breast of the cancer, fused together. The place of their connection can be found along the connecting seam.

On the head of the crayfish, there is a pointed spine, a pair of small eyes and two pairs of mustaches. These organs are responsible for touch.
The limbs of the cancer (8 pieces) are attached to the chest part: 3 of them are responsible for delivering food to the mouth, 2 others are claws, and 4 others are responsible for moving the cancer. The gills are also found in the cephalothorax.