Angiosperm pollinivory in a Cretaceous beetle

Despite the crucial importance of flower-visiting insects in modern ecosystems, there is little fossil evidence on the origins of angiosperm pollination. Most reports of pollination in the Mesozoic fossil record have been based on the co-occurrence of the purported pollinators with pollen grains and assumed morphological adaptations for vectoring pollen. Here, we describe an exceptionally preserved short-winged flower beetle (Cucujoidea: Kateretidae) from mid-Cretaceous amber, Pelretes vivificus gen. et sp. nov., associated with pollen aggregations and coprolites consisting mainly of pollen, providing direct evidence of pollen-feeding in a Cretaceous beetle and confirming that diverse beetle lineages visited early angiosperms in the Cretaceous. The exquisite preservation of our fossil permits the identification of the pollen grains as Tricolpopollenites (Asteridae or Rosidae), representing a record of flower beetle pollination of a group of derived angiosperms in the Mesozoic and suggesting that potentially diverse beetle lineages visited early angiosperms by the mid-Cretaceous. Using the preserved remains of a short-winged flower beetle in mid-Cretaceous amber, this Article provides some of earliest clues as to the origins of angiosperm pollination.

Automated summary

An exceptionally preserved short-winged flower beetle fossil provides evidence of pollen-feeding activities in a Cretaceous beetle, confirming diverse beetle lineages visited early angiosperms. The identification of Tricolpopollenites pollen grains suggests potentially diverse beetle lineages visited early angiosperms by the mid-Cretaceous. This fossil offers some of the earliest clues to the origins of angiosperm pollination.