''Aphis pomi'', commonly known as the apple aphid (the literal meaning of its

binomial name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

), or the green apple aphid, is a

true bug Hemiptera (; ) is an order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from to around ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Aphididae. It is found on young growth of

apple An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple fruit tree, trees are agriculture, cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, wh ...

trees and on other members of the rose family where it feeds by sucking

sap Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant. Sap is distinct from latex, resin, or cell sap; it is a separa ...

. Reproduction is mainly by

parthenogenesis Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development ...

, in which unmated females give birth to live young.

Description

Wingless females have a pear-shaped bright green or yellowish-green body, undusted with wax particles, and grow to a maximum length of about . The cauda (tail-like elongation of the body) and

cornicle The cornicle (or siphuncule) is one of a pair of small upright backward-pointing tubes found on the dorsal side of the 5th or 6th abdominal segments of aphids. They are sometimes mistaken for cerci. They are no more than pores in some species. ...

s are black and the antennae and legs are pale with brown tips. Winged females have a black thorax and green abdomen, often with three pairs of blackish spots on the front three segments and dark semicircular spots in front of and behind the cornicles.

Distribution

''Aphis pomi'' has a widespread distribution in Europe, western Asia as far east as India and Pakistan, North Africa and North America. In Israel and the eastern United States, the more common aphid on apple trees is the spirea aphid, ''

Aphis spiraecola ''Aphis spiraecola'' is a species of aphid described in 1914 by Edith Marion Patch. Its common names include green citrus aphid, Spirea aphid, and apple aphid. It is distributed worldwide, and is most abundant in the United States. It has a dip ...

''. This has a wide range of host plants and a faster rate of reproduction than ''A. pomi'', especially at high temperatures.

Ecology

Besides occurring on apple (''Malus domestica''), ''Aphis pomi'' infests other plants in the family

Rosaceae Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. Among the most species-rich genera are ''Alchemilla'' (270), ''Sorbus ...

including

pear Pears are fruits produced and consumed around the world, growing on a tree and harvested in the Northern Hemisphere in late summer into October. The pear tree and shrub are a species of genus ''Pyrus'' , in the family Rosaceae, bearing the p ...

(''Pyrus communis ''),

hawthorn Hawthorn or Hawthorns may refer to: Plants * '' Crataegus'' (hawthorn), a large genus of shrubs and trees in the family Rosaceae * ''Rhaphiolepis'' (hawthorn), a genus of about 15 species of evergreen shrubs and small trees in the family Rosace ...

(''Crataegus monogyna''), medlar (''Mespilus germanica''),

quince The quince (; ''Cydonia oblonga'') is the sole member of the genus ''Cydonia'' in the Malinae subtribe (which also contains apples and pears, among other fruits) of the Rosaceae family (biology), family. It is a deciduous tree that bears hard ...

(''Cydonia oblonga''),

mountain ash Mountain ash may refer to: * ''Eucalyptus regnans'', the tallest of all flowering plants, native to Australia * Mountain-ashes or rowans, varieties of trees and shrubs in the genus ''Sorbus'' See also * Mountain Ash, Rhondda Cynon Taf Mountai ...

(''Sorbus aucuparia''),

rose A rose is either a woody perennial flowering plant of the genus ''Rosa'' (), in the family Rosaceae (), or the flower it bears. There are over three hundred species and tens of thousands of cultivars. They form a group of plants that can be ...

(''Rosa'') and spiraea (''Spiraea''). It is an

autoecious A heteroecious parasite is one that requires at least two hosts. The ''primary host'' is the host in which the parasite spends its adult life; the other is the ''secondary host''. Both hosts are required for the parasite to complete its life cycle ...

species, completing its life cycle on a single host species. Overwintering eggs hatch in spring and the aphids colonise the growing tips of the shoots causing the edges of the leaves to curl. These aphids are all

viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...

females and give birth to other wingless aphids by

. In June some winged females are produced and these migrate to other branches and trees, and large aggregations build up by late summer. There may be ten to fifteen generations of aphid during the season and winds may disperse the winged forms over many kilometres. Sexual forms are produced in the autumn, winged egg-laying females and wingless males. Mating takes place and eggs are laid near the tips of the shoots, sometimes in large batches. These are green at first but soon turn black. Ants are often present among the colonies, feeding on the honeydew secreted by the aphids. The presence of the ants is beneficial to the aphids as the ants deter and remove predators that might feed on the aphids; these include the larvae of the midge ''

Aphidoletes aphidimyza ''Aphidoletes aphidimyza'', commonly referred to as the aphid midge, is a midge whose larvae feed on over 70 aphid species, including the green peach aphid. Description The adults are small (less than long), black, delicate flies (similar ...

'' and

parasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...

s which lay their eggs in the aphid nymphs. High levels of infestation by the aphids can cause stunted shoots, disfigured fruit and premature leaf fall, especially in young trees, and sooty mould may form on excess honeydew secretions.

References

{{Taxonbar, from=Q2382963 Hemiptera of Asia

pomi Pomi ( hu, Remetemező; Hungarian pronunciation: ) is a commune of 2,365 inhabitants situated in Satu Mare County, Romania Romania ( ; ro, România ) is a country located at the crossroads of Central, Eastern, and Southeastern Europe. It ...

Insects described in 1773 Taxa named by Charles De Geer