''Aonidiella orientalis'' is a species of insect in the family
Diaspididae
Diaspididae is the largest family of scale insects with over 2650 described species in around 400 genera. As with all scale insects, the female produces a waxy protective scale beneath which it feeds on its host plant. Diaspidid scales are far mo ...
, the armored scale insects. It is known commonly as the Oriental yellow scale.
[''Aonidiella orientalis'' (Oriental yellow scale).]
Invasive Species Compendium. CABI. It is an
agricultural pest
A pest is any animal or plant harmful to humans or human concerns. The term is particularly used for creatures that damage crops, livestock, and forestry or cause a nuisance to people, especially in their homes. Humans have modified the environ ...
on a wide variety of crop plants.
[
]
Description
This is a scale insect, a tiny insect which is most easily identified by the female, which attaches itself to a host plant, loses its legs, and remains stationary covered by a somewhat rounded scale-like shield of wax. In this species, the female forms a flat, circular scale which is white, brown, or yellow in color.[ It is up to 2.6 millimeters long.][''Aonidiella orientalis'' (Oriental scale).]
Arthropods of Economic Importance. World Biodiversity Database. ETI Bioinformatics. The insect within is no more than 1.4 millimeters long.[ The winged male of this species also produces a scale.][
]
Distribution
This species is likely native to Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...
. It can be found nearly worldwide today because it has been introduced to many areas with shipments of plants and then began a slow spread. It is common in many tropical and subtropical areas, and it can survive in greenhouses in cooler regions. It is not known from Europe.[ Some ports check for this and other scales in ]quarantine
A quarantine is a restriction on the movement of people, animals and goods which is intended to prevent the spread of disease or pests. It is often used in connection to disease and illness, preventing the movement of those who may have been ...
d plant shipments.[
]
Biology
The female attaches to the surface of a plant, forms a waxy shield, and lays eggs beneath it.[ They are often ]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 ...
, producing live young instead of laying eggs.[ The ]larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
...
e emerge and leave the shield; at this point they are called "crawlers". They roam the plant, feeding on sap by inserting their stylets. Males reach the adult stage at about 19 days. Females reach adulthood and yield the next generation of larvae at about 44 days.[ Males have wings but no mouthparts, and they do not feed.][ There are about three to five generations per year, depending on conditions.][
]
Impact
This species is highly polyphagous: it can feed on a wide variety of plant taxa. It has been found on most every kind of plant except conifers. It is problematic in many kinds of plant crops, including fruits, vegetables, herbs, medicinal plants, fiber plants, oil plants, and ornamental plants.[ Crops affected include sisal hemp, ]tea
Tea is an aromatic beverage prepared by pouring hot or boiling water over cured or fresh leaves of ''Camellia sinensis'', an evergreen shrub native to East Asia which probably originated in the borderlands of southwestern China and north ...
, cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor pe ...
, mastic
Mastic may refer to:
Adhesives and pastes
*Mastic (plant resin)
*Mastic asphalt, or asphalt, is a sticky, black and highly viscous liquid
* Mastic cold porcelain, or salt ceramic, is a traditional salt-based modeling clay.
*Mastic, high-grade con ...
, oil palms
''Elaeis'' () is a genus of palms containing two species, called oil palms. They are used in commercial agriculture in the production of palm oil. The African oil palm ''Elaeis guineensis'' (the species name ''guineensis'' referring to its cou ...
, neem
''Azadirachta indica'', commonly known as neem, nimtree or Indian lilac, is a tree in the mahogany family Meliaceae. It is one of two species in the genus '' Azadirachta'', and is native to the Indian subcontinent and most of the countries in Afr ...
, and many foods and flowers.[
The insect damages the plant by sucking sap, weakening it. The physical damage includes discoloration and deformation of leaves. Flowers and fruits fail to develop. When the insects feed on the fruits they are discolored and warped, reducing their value on the market. Infestations can kill plants, even established trees.][
Severe impacts can occur in places where the insect is newly introduced. It was first seen in papaya crops in ]Queensland
)
, nickname = Sunshine State
, image_map = Queensland in Australia.svg
, map_caption = Location of Queensland in Australia
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, establishe ...
in 1988, and it rapidly became the most serious pest in the local industry.[ It was first found on mangoes in ]Israel
Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...
in 1980; now it is established in mango groves throughout the surrounding region and is spreading to other local crops, such as olive and guava.[Ofek, G., et al. (1997)]
The control of the oriental red scale, ''Aonidiella orientalis'' Newstead and the California red scale, ''A. aurantii'' (Maskell) (Homoptera: Diaspididae) in mango orchards in Hevel Habsor (Israel).
''Alon Hanotea'', 51(5), 212-218. Some groves are doubly infested, also harboring populations of the related red scale (''Aonidiella aurantii'').[ It was first found on neem in ]Cameroon
Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west-central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; the C ...
in 1985 and had spread over one million kilometers by 1998, infesting many economically important trees.
Control
Infested twigs, branches, and shoots can be removed from trees, slowing the spread of the scale. Pesticides have been used, but are less popular now as attention turns to biological pest control. There are many natural enemies of the scale which can be reared and released in infested orchards, reducing scale populations.[
Natural enemies have been trialed in Queensland's papaya groves. Good results were observed with the ]parasitoid wasp
Parasitoid wasps are a large group of hymenopteran superfamilies, with all but the wood wasps (Orussoidea) being in the wasp-waisted Apocrita. As parasitoids, they lay their eggs on or in the bodies of other arthropods, sooner or later causin ...
s '' Comperiella lemniscata'' and ''Encarsia citrina
''Encarsia'' is a large genus of minute parasitic wasps of the family Aphelinidae. The genus is very diverse with currently about 400 described species and worldwide distribution. Noyes, J. S. 2003Universal Chalcidoidea database/ref> The number ...
''.lady beetles
Coccinellidae () is a widespread family of small beetles ranging in size from . They are commonly known as ladybugs in North America and ladybirds in Great Britain. Some entomologists prefer the names ladybird beetles or lady beetles as they ...
'' Lindores lophanthae'', '' Chilocorus circumdatus'', and '' C. baileyi'' have been helpful in severe infestations.[Oriental Scale.]
Department of Agriculture and Fisheries, Queensland.
References
{{Authority control
Aspidiotina
Agricultural pest insects
Insects of Asia
Insects described in 1894