Because the lips of Sawshark are long, and it is flat, and there is a tooth on right and left both sides, it seems to be "a saw". The size of the tooth of this "saw" is not same, and the teeth of big things and small things form a line in turn. There is a long mustache one pair of right and left to lips. There is not a splinter, and the dorsal fin does not have the ventral fin with 2, too. It lives at the bottom of the shallow sea. It uses the mustache in long lips to look for a small animal in the sand of the bottom of the sea.