Kingdom Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Superorder: Batoidea(Rays)
Order: Rajiformes
Family: Rajidae
and
Family: Anacanthobatidae
Like sharks, but flatter. Skates look like birds and swim as if they were flying, having two enlarged fins on either side. They look somewhat like a kite, with their diamond-shaped body and long, thin tail. Or a cross between a butterfly and a squid, fluttering oozily through the ocean shallows. Their two large 'wings' are technically enlarged pectoral fins, and merge so smoothly into the body that skates appear to be nothing more than a set of living wings. They are bottom dwellers, and have their eyes on the top of their heads like a flounder.
Skates are cartilaginous fish, and are closely related to sharks. They are a type of rays, and the families of skates include more than 200 different species. Some species can get to be up to 4 feet long and weigh up to 100 pounds. Most are smaller, and most are harmless. They are bottom dwellers, and eat other bottom dwellers such as sea squirts, snails, crabs and clams. Not humans, tho. Skates are often colored to blend in with the ocean floor (and are countershaded with light wavy markings on their bottoms to look like the surface of the ocean from below), and are often hard to spot.
The mermaids' purses you find washed up on the beaches are the skates' egg sacks.