Conspicuousness and toxicity of Coccinellidae: An aposematic review

Abstract

Coccinellids (commonly known as ladybirds) mostly exhibit bright clouration and play a vital role in biological control of pests of important crops such as aphids and scale insects. Nevertheless, they are characterized by the possession of a group of unpleasant and poisonous defence chemicals. These chemicals along with bright colouration form an aposematic enemy barrier. Many conspicuously coloured adults of coccinellidae have elytra with contrasting red-and-black or yellow-and-black patterns generally serving as aposematic (warning) colouration. Larvae and pupae of ladybirds may also be aposematically coloured with dark and bright areas on their surface. In this review, the significance of colouration and toxicity in ladybirds has been highlighted.

Keywords

• aposematism
• warning signals
• chemical defence
• carotenoids
• alkaloids