The Evolution of Flower Beetles as Visitors and Pollinators

An estimated 20% of about 400,000 species of beetles (Coleoptera) are flower visitors. Despite this huge taxonomic and natural history diversity, beetle-flower interactions have historically been overlooked and summarized as inefficient mess-and-soil pollinators associated with an easily recognizable flower syndrome. Here, we combine classical and artificial intelligence-supported review methods to discuss the reasons for this neglect, which include biased documentation and pervasive views that reflect only a subset of beetle-flower interactions. We review general trends in extant and fossil flower beetle morphology, behavior, and diversity, as well as the diversity of the flowers they visit. We discuss how the fossil record and molecular phylogenetics show both ancient associations preceding angiosperm dominance and numerous cases of derived associations leading to more recent diversification. The context dependency of beetle-flower interaction outcomes and their pervasiveness could be leveraged to improve our understanding of insect diversification processes and the costs and benefits of different pollination systems.