This fascinating beetle can change its colour from a brilliant, shiny metallic gold to dull red in a short period of time when stressed. There is a thin layer of moisture between the transparent cuticle and an inner layer of the elytra, and the beetle is able to change colour by controlling the amount of moisture present. The gold colour is produced by an optical illusion resulting from the reflection of light through the layer of liquid. When the insect is stressed, or when it dies, the liquid between the two layers of its shell thins to the point where there is not enough moisture to produce the illusion.