This beautiful iridescent metallic green insect is the male thick-kneed flower beetle — the female is less colourful, and doesn’t have the swollen femurs. All the coloration is structural, created by microscopic ridges of the cuticle, the right size to interfere with visible light. The insect’s Latin name is Oedemera nobilis, the “noble swollen-parted” (yes, like Oedema, swelling), presumably describing the thick “knees” and the insect’s handsome appearance.