The special pigment for colour change in chameleon is

The special pigment for color change in a chameleon is chromatophore. Chromatophores are specialized cells found in the skin of many animals, including chameleons, that can change color rapidly to help the animal blend into its surroundings or communicate with others of its species. Chromatophores contain different pigments, including melanin and carotenoids, which can be controlled by muscles to expand or contract and change the color and pattern of the animal's skin. For example, when a chameleon wants to blend in with green leaves, it will expand the green pigment-containing chromatophores, and when it wants to appear darker to regulate body temperature, it will expand the black chromatophores. This ability to change color is a remarkable adaptation that helps chameleons avoid predators and attract mates, and it's all thanks to the unique and specialized cells called chromatophores.