Earliest mimicking of flowering plants by insects

Abstract

Mimicry, a complex visual defensive strategy, shapes ecological dynamics and evolution by influencing predator–prey interactions. Insect mimicry of plant structures drives their co-evolution with plants. However, fossil evidence of insect–angiosperm mimicry is exceedingly scarce and has previously been confined to the Cenozoic, although the occurrence of angiosperms extends far earlier. Here, the earliest known insect mimicking angiosperm leaves, Dryadithone cretacea gen. et sp. nov. (Neuroptera: Ithonidae), is reported from the mid-Cretaceous Kachin amber. The sophisticated camouflage of this new species, achieved by mimicking the midvein, pinnate framework, and reticulate venation of angiosperm leaves through its forewing shape and venation, was further validated by the Siamese Neural Network. This mimicry deceived a wider range of visual predators and compensated for the disadvantages from large body size. Dryadithone cretacea extends the earliest record of insects mimicking angiosperms to the mid-Cretaceous, shedding light on complex insect behaviors and the intricate ecological interactions among plants, insects, and higher trophic-level predators during this period of flowering-plant proliferation.