The diet of a bony fish includes plankton, crustaceans, invertebrates and other fish, depending on the species. There are over 28,000 species of bony fish.
Bony fish are classified by their skeletons, which are composed of true bone rather than cartridge. Lungfish, ocean sunfish, needle fish and puffers, as well as many others, are all classified as bony fish. Bony fish possess gills for respiration, swim bladders for buoyancy and operculums that enable them to breathe without moving. Bony fish can vary greatly in size, from 0.5 inch to 11 feet long, and can weigh anywhere between a fraction of an ounce and 5,000 pounds.