In the members of osteichthyes (bony fishes) skin is covered by exoskeleton made of large cycloid scales impermeable to water. They reduce osmotic water loss in marine environment and entry of water in fresh environment.
In the members of osteichthyes (bony fishes) skin is covered by exoskeleton made of large cycloid scales impermeable to water. They reduce osmotic water loss in marine environment and entry of water in fresh environment.