Macrosiphum euphorbiae, the potato aphid, is a sap-sucking pest insect in the family Aphididae.

Macrosiphum euphorbiae originated in North America but it has spread to the temperate parts of Europe and Asia and is found in all areas in which potatoes are grown.

[2] The wingless female potato aphid is green or occasionally pink, often with a darker dorsal stripe.

The siphunculi are pale coloured, cylindrical with dark tips and operculi, and are about one third the length of the body.

[4] They usually emerge in April and begin feeding on perennial weeds, preferring plants in the family Chenopodiaceae.

High temperatures or heavy rainfall may reduce infestations and the numbers are naturally controlled by predators, parasites and pathogens.