Kingdom: Animalia

Phylum: Chordata

Class: Chondrichthyes

Order: Rajiformes

Family: Rajidae

Description

The jaws of the skate is wide and powerful it located on the ventral side of the organism as it is feeds on the bottom surface. There are between 40–56 rows of teeth present in each of the jaws. The repeated jaw opening and closing generates water flow in and out of the buccal cavity and resuspends food and sand; and lastly, suction.  The jaws of skates and rays are only loosely connected to the cranium, a development which allows these fish to protrude their jaws a short distance from their heads when feeding.  This action, in turn, creates suction for picking or pulling prey off the bottom, along with sediment.  The later is ejected out of the mouth, spiracles, or gill slits once the food is separated from the sediment in the mouth.

Reference:

http://www.marinebiodiversity.ca/skatesandrays/feeding.htm