Common maple aphid

<em>Periphyllus testudinaceus</em>, the common maple aphid, is a small sap-sucking insect in the family Aphididae, associated primarily with maple trees of the genus Acer. It is recorded from Denmark, Norway, Sweden, and the United States. This species has not been formally evaluated for IUCN conservation status. The common maple aphid typically forms colonies on the undersides of maple leaves and along young shoots, feeding on phloem sap and potentially causing leaf curling, discoloration, and reduced tree vigor in heavy infestations. Like many aphid species, it produces honeydew as a metabolic byproduct, which attracts ants that may protect the aphid colonies in exchange. The species exhibits complex life cycles that can involve both sexual and asexual reproduction across seasons. Biological traits including body size, average lifespan, and precise dietary specializations beyond maple sap feeding remain incompletely documented. The common maple aphid is part of the broader community of invertebrates dependent on maple trees across temperate Northern Hemisphere regions.