The Aphididae are a very large insect family in the aphid superfamily (Aphidoidea), of the order Hemiptera. These insects suck the sap from plant leaves. Several thousand species are placed in this family, many of which are considered plant/crop pests. They are the family of insects containing most plant virus vectors (around 200 known) with the green peach aphid (Myzus persicae) being one of the most prevalent and indiscriminate carriers.