Distribution of Drepanaphis acerifoliae – aphid pest of Acer trees – faced with global climate change

The genus Drepanaphis del Guercio currently includes 16 species, all of which are found in North America. Representatives of this genus are narrow oligophages associated mainly with plants of the genus Acer. Previous studies have focused only on the morphology of selected species, while not considering their geographical distribution. Among all species, the painted maple aphid Drepanaphis acerifoliae deserves particular attention, because it represents the broadest range in North America and is the only species of this genus to be found outside of its natural range, i.e. in Europe. Thanks to suitable niche modelling based on a maximum entropy model, we were able to present maps with the potential distribution of D.acerifoliae in its natural range. In North America, its distribution coincides with the natural range of the host plants (native to the eastern part), as well as the areas where they are planted (the western part). An extrapolation of these results to the area of Europe allowed for the designation of places where the aphids can find suitable climatic conditions for developing and expanding their spatial distribution. The model indicated the Mediterranean basin, almost all of Italy, excluding mountainous areas, Spain, Portugal, France, Belgium, the Netherlands, the western part of Germany, the southeast and central part of Great Britain, Hungary and the Balkan Peninsula. In a more continental view, the model pointed to areas stretching from the middle of eastern Ukraine, including Crimea, through Russia, to northern parts of Kazakhstan along the border with Russia. Additionally, the impact of climate change on the spread of the species within the next 80 years was analysed, both in North America and Europe. Models considering the potential future climate changes indicate that D.acerifoliae may find suitable niches further north of its current ranges. In North America, this is mostly areas of eastern Canada, while in Europe it includes the central and eastern part and the Asian part of Russia.