Acyrthosiphon pisum

Definition

A globally distributed aphid species in the family Aphididae (Hemiptera: Sternorrhyncha) that feeds phloem sap from leguminous plants including pea, clover, alfalfa, and broad bean. The pea aphid is a major agricultural pest and one of the foremost model organisms for insect genetics, development, symbiosis, and evolutionary biology; its genome was among the first published for any hemipteran.

Etymology

Greek akros (tip, extremity) + rhis/rhinos (nose, snout) + siphon (tube, pipe), referring to the elongated rostrum; Latin pisum (pea), the principal host plant.

Example

Laboratory colonies of Acyrthosiphon pisum are used to study the obligate mutualism between aphids and their intracellular bacterial symbiont Buchnera aphidicola, as well as the genetic basis of polyphenism producing winged versus wingless morphs in response to crowding or host-plant quality.

Synonyms

• Pea aphid

Related Terms

• Aphididae
• Hemiptera
• phloem feeding
• Buchnera aphidicola
• Polyphenism
• Parthenogenesis
• model organism

Usage Notes

Specialists recognize several subspecies or host races (e.g., A. pisum pisum, A. pisum onobrychidis, A. pisum ononis) that show partial reproductive isolation and host-plant specialization. The name is sometimes misspelled 'Acyrthosiphon' in older literature. In agricultural contexts, 'pea aphid' may also loosely refer to other Acyrthosiphon species such as A. kondoi (blue alfalfa aphid).