Goncalves and Oliveira (2016) [22] categorized five stages of melanosis formation: (1) Gram positive and negative bacteria and fungi trigger the alignment of serine proteinase, (2) pro polyphenoloxidase then activates to become polyphenoloxidase (PPO), (3) PPO acts as a catalyst to convert phenol into colorless quinone, (4) oxidization of quinone results in melanin, and (5) melanin is responsible for melanosis formation in the crustacean carapace. This evidence concerns the gene PPOX and freckles.