Answer: chromatophores
Step-by-step explanation:
The coloration of fishes is due to special cells called chromatophores. Chromatophores are referred to as the cells which produces color. They are seen in animals such as reptiles, fish,amphibians, and crustaceans.
On the other hand, mammals and birds, have a class of cells that is refered to as melanocytes for coloration. The main function of chromatophores is simply for camouflage.