What is the name of a species cartilaginous fish with round flattened body and wing like pectoral fins?

The cartilaginous fish you are describing is likely a ray.

Rays are characterized by their:

* Flattened, disc-shaped bodies

* Large, wing-like pectoral fins that are fused to the head

* Cartilaginous skeletons (like all other cartilaginous fish, such as sharks)

There are many different species of rays, each with their own unique characteristics. Some common examples include:

* Stingrays: Known for their venomous spines on their tails.

* Manta rays: The largest of the rays, with wingspans up to 29 feet.

* Eagle rays: Have long, narrow bodies and distinctive "wings" that give them their name.

Let me know if you have more information about the specific ray you are looking for and I can try to help you narrow it down!