單元大綱

      • Eats mainly shellfish, polychaetes, crustaceans, and fish.

      • There are two pairs of mustaches on the ventral anterior side of the lower jaw. They are hard cartilaginous mustaches, with fine protrusions on the surface of the mustaches. There are taste buds in the opening of the protrusion, which senses chemical substances (odors) in the water. Hard mustaches extend down in front of the mouth, making it suitable for finding food in the mud and inhaling it by mouth. They are similar to the mustaches of cod, which is a demersal fish.

      • Adult fish have no teeth and swallow food as if they are inhaling it.

      • The loop-shaped elongated stomach has an ampulla at the end of the stomach (the pyloric region) with a thick muscular layer. This muscle layer contracts and grinds food into a paste. It plays a role similar to that of the gizzards of birds.