Flounder and Sole are the names given to most U.S. flat fish and once on the plate it nearly impossible to tell what species it is.
The term flat fish describes a species that is born swimming upright and as it matures it rolls over on its side. Also, when they are born they have an eye on each side. After they roll over both eyes work their way to the side that is on top.
A flat fish is easy to filet as they do not have many pin bones to work around. A European Dover Sole is the true original sole and it is the most expensive. It is imported from Europe The U.S. Dover sole is found along the west coast from California to Alaska.
Some of the other species, identified by the side their eyes are on, are Fluke, Blackback Flounder, Witch Flounder, Sea Dab, Yellow Tail Flounder, Southern Flounder, Pacific Sole, Butter Sole, Rex Sole, Rock Sole, Yellow Fin Sole, Summer Flounder and Pacific Sand Dab. These are all sold as Flounder and Sole.