The pea aphid is a model organism whose genome has been sequenced and annotated. Acyrthosiphon pisum is a rather large aphid whose body can reach 4mm in adults. Pea aphids also show hereditary body color variations of green or red/pink. The green morphs are generally more frequent in natural populations.
Found on host plants. The most common pest aphid on legumes like alfalfa in northwestern N. America. It causes hundreds of millions of dollars of crop damage a year.