The Macrosiphini are the predominant group of aphidson herbaceous plants in Britain, and the world. Thereare 305 British species and subspecies, comprising 49%of the 620 Aphididae on the British list. They includemany important pest species, some of which are highlypolyphagous, but there are also very many more speciesfeeding more-or-less specifically on indigenous andnaturalised plants and playing a significant role innatural food chains. This Handbook provides a checklistand a list of native host plants, along with keys totribes, genera and species. Biological informationis provided about each species.