Superorder: Batoidea
Commonly known collectively as Rays, this is the largest collection of cartilaginous fish with over 600 species (a tiny number when compared to many collections of invertebrates, I know). Pectoral fins are joined to the heads and gills on the ventral surfaces are distinguishing features.
There are 4 Orders described here.
There are 4 Orders described here.
Order
Myliobatiformes: Rays / Stingrays
Pristiformes: Sawfish
Rajiformes: Guitarfish / Skates