.Mackerel A salt.water fish which is of considerable importance to the fishing It industry. shoals protection. The moves in for female lays about 4OO OOO eggs. Neoceratodus : Lungfish A bony fish with large thin scales, lt has gills and a single lung and lives in stagnantwater. lt belongs to the Dipnoi or lungfish. Some scientists think link between fish and thai this is a amphibians; ...some place them in either group. Latimeria: Coelacanth This "living" fossil was discovered in 1938. These large, blue grey fish are found in deep water and their fins are fringed lobes. Previously they were only known from Devonianfossils. They have adegenerate lung and are related to the Dipnoi. The carp, trout, perch, eel and mackerel are all fish with the following characteristics in common: cold-blooded, aquatic vertebrates with a bony skeleton, swim bladder present, a All of gills covered with an with flat, protective scales. series operculum and usually covered these fish are placed in the group 0steichthyes.