''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 binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

), or the green apple aphid, is a true bug in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Aphididae 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/cr ...

. It is found on young growth of

apple An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are agriculture, cultivated worldwide. The tree originated ...

trees and on other members of the

rose family Rosaceae (), the rose family, is a family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. The family includes herbs, shrubs, and trees. Most species are deciduous, but some ...

where it feeds by sucking sap. Reproduction is mainly by

parthenogenesis Parthenogenesis (; from the Greek + ) is a natural form of asexual reproduction in which the embryo develops directly from an egg without need for fertilization. In animals, parthenogenesis means the development of an embryo from an unfertiliz ...

, 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 cercus, cerci. They are no more than pores in some spe ...

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 family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus '' Rosa''. The family includes herbs, shrubs, and trees. Most species are deciduous, but som ...

including

pear Pears are fruits produced and consumed around the world, growing on a tree and harvested in late summer into mid-autumn. The pear tree and shrub are a species of genus ''Pyrus'' , in the Family (biology), family Rosaceae, bearing the Pome, po ...

(''Pyrus communis ''), hawthorn (''Crataegus monogyna''), medlar (''Mespilus germanica''),

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

(''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, a town ...

(''Sorbus aucuparia''),

rose A rose is either a woody perennial plant, perennial flowering plant of the genus ''Rosa'' (), in the family Rosaceae (), or the flower it bears. There are over three hundred Rose species, species and Garden roses, tens of thousands of cultivar ...

(''Rosa'') and

spiraea ''Spiraea'' , sometimes spelled spirea in common names, and commonly known as meadowsweets or steeplebushes, is a genus of about 80 to 100 species

(''Spiraea''). It is an

autoecious A heteroecious parasite is one that requires at least two Host (biology), 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 compl ...

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 In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juve ...

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'' 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 A nymph (; ; sometimes spelled nymphe) is a minor female nature deity in ancient Greek folklore. Distinct from other Greek goddesses, nymphs are generally regarded as personifications of nature; they are typically tied to a specific place, land ...

. 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 Insects described in 1773 Taxa named by Charles De Geer