Protaetia affinis is usually 25–30 mm long, with a thick-set body. Both sides of its body are usually metallic emerald, however blue, violet, red, black and bicolor variations have been described as subspecies. The elytra have very small punctures, and no horizontal striae. The legs are also green, with white stripes.
Lifestyle
Females lay clutches of 4-7 eggs. Larvae develop in cavities in tree branches, where they feed on decaying plant matter. Adults feed on sap from trees, seeming to preferfruit trees. Occasionally they can be found on flowering plants.