Bony Fish Diagram. Paddles shown in the steam conditioning. Eg climatius bothriolepis.
The exoskeleton is like placoid scales. A a bony fish with the operculum held open to show the gills b a single gill removed from a bony fish c a drawing of a gill showing gill filaments oxygen absorption gill arch supporting structure and gill rakers comb like structure for filtering. Bony ridges characterize the bony fishes osteichthyes.
These scales rarely overlap.
Their exoskeleton is in the form of shields and the endoskeleton is bony. The exoskeleton is like placoid scales. The heterostraci and osteostraci were regarded as bony fishes until cope 1889 suggested to include them with lampreys and hagfishes in the taxon agnatha jawless. They are of two types.