Aonidiella orientalis
(oriental yellow scale)

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Identity

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Preferred Scientific Name

• Aonidiella orientalis (Newstead, 1894)

Preferred Common Name

• oriental yellow scale

Other Scientific Names

• Aonidiella cocotiphagus (Marlatt) Ferns, 1938
• Aonidiella taprobana (Green) MacGillivray, 1921
• Aspidiotus cocotiphagus Marlatt, 1908
• Aspidiotus orientalis Newstead, 1894
• Aspidiotus osbeckiae Green, 1896
• Aspidiotus pedronis Green, 1905
• Aspidiotus taprobanus Green, 1905
• Chrysomphalus orientalis (Newstead) Lindinger, 1913
• Chrysomphalus pedroniformis Cockerell & Robinson, 1915
• Chrysomphalus pedronis (Green) Sanders, 1906
• Evaspidiotus orientalis (Newstead) Leonardi, 1898
• Furcaspis orientalis (Newstead) MacGillivray, 1921

International Common Names

• English: oriental red scale; oriental scale; scale, oriental; scale, oriental red; scale, oriental yellow; scale, red

EPPO code

• AONDOR (Aonidiella orientalis)

Taxonomic Tree

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• Domain: Eukaryota
•     Kingdom: Metazoa
•         Phylum: Arthropoda
•             Subphylum: Uniramia
•                 Class: Insecta
•                     Order: Hemiptera
•                         Suborder: Sternorrhyncha
•                             Unknown: Coccoidea
•                                 Family: Diaspididae
•                                     Genus: Aonidiella
•                                         Species: Aonidiella orientalis

Notes on Taxonomy and Nomenclature

Top of page Aonidiella orientalis was first described by Newstead in 1894, as Aspidiotus orientalis, from an undetermined host in India. It has been redescribed as Aspidiotus osbeckiae Green, from Osbeckia in Sri Lanka, as Aspidiotus cocotiphagus Marlatt, from coconut in Cuba, and as Chrysomphalus pedroniformis Cockerell and Robinson, from grapes in the Philippines. This armoured scale is now located in the genus Aonidiella Berlese and Leonardi, within the tribe Aspidiotini of the subfamily Diaspidinae (McKenzie, 1938).

Description

Top of page As with all armoured scale species (Diaspididae), adults of A. orientalis are covered with a scale or cover that is morphologically separate from the body. The adult female is less strongly reniform than typical for its genus, with less developed prosomatic lobes (McKenzie, 1938).

The adult female scale cover is circular and flat in shape, almost white to pale brown or yellow, with yellow to dark brown exuviae positioned more or less centrally. Adult female insect with prosoma pyriform, expanding to subcircular and becoming moderately sclerotized around margins at maturity. Pygidium quite well sclerotized dorsally. Median lobes distinctly larger than second lobes, with fourth lobes represented by small points on either side. Plates lateral to third lobes not fringed, each with a long fleshy process present at mesal angle. Abdominal segments 1 to 3 with a submarginal row or cluster of dorsal macroducts present on each side. Thoracic tubercles are minute. Perivulvar pores present in 4 or 5 groups, ranging from 19 to 32 in number. Prevulvar scleroses and apophyses absent. Adult females measure 1.0-1.4 mm in length when slide-mounted (Williams and Watson, 1988).

Male scales are elongate to oval in shape and similar to females, but smaller, with yellow exuviae near one end (Williams and Watson, 1988).

Distribution

Top of page A. orientalis is a tropical and subtropical species with a wide distribution, including the West Indies, Middle East, India, East Africa and South Africa, southern Asia and northern Australia (CIE, 1978). It has been accidentally distributed worldwide on host plants and also occurs in greenhouses in temperate areas.

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Risk of Introduction

Top of page Diaspididae are generally of quarantine importance, as they are primarily spread on plant stock through human activity. They are regularly intercepted at plant quarantine inspection centres.

A. orientalis was reported to be relatively new to the South Pacific area by Williams and Watson (1988), and therefore to be of potential phytosanitary risk. In the Caribbean it is regarded as an economic plant pest of quarantine importance (Schotman, 1989).

Hosts/Species Affected

Top of page A. orientalis is highly polyphagous. It can attack almost any host except conifers, according to Williams and Watson (1988). It can be an economic pest of crops from diverse families. These include: species of Citrus and Ficus, mango, papaya, bananas and other fruits; palm trees, including coconut and arecanut (Areca catechu); and tea (Camellia sinensis).

The distribution map includes records based on specimens of A. orientalis from the collection in the Natural History Museum (London, UK). These are noted in the List of Countries (NHM, undated).

Host Plants and Other Plants Affected

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Growth Stages

Top of page Flowering stage, Fruiting stage, Seedling stage, Vegetative growing stage

Symptoms

Top of page Direct feeding damage on leaves and removal of plant sap reduces plant vigour. Feeding often causes depressions, discoloration and distortion of leaves. Heavy infestations can result in the yellowing of foliage and defoliation, dieback of small twigs and premature fruit drop (Rajagopal and Krishnamoorthy, 1996). Cosmetic damage may also occasionally occur to fruits.

List of Symptoms/Signs

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Biology and Ecology

Top of page The eggs are laid under the female scale cover. The larvae (forst instar crawlers) emerge from under the female, and crawl for several hours until they find suitable host plant tissue into which to insert their stylets. The females subsequently remain immobile, with successive moults adding to the size of the scale. Females have two moults before attaining maturity. The males have additional prepupal and pupal moults before attaining a winged adult stage. Adult males lack mouthparts, do not feed and are relatively short-lived. Mating and the laying of eggs is the most important route by which crawlers are produced (Rajagopal and Krishnamoorthy, 1996).

In laboratory studies, males took an average of 19.5 days to proceed from the crawler stage to adult and females took an average of 44.2 days from the crawler stage to production of the first crawler of the subsequent generation (Elder and Smith, 1995).

In Iran, five generations per year were recorded, with the maximum population density in the fourth and fifth generations. Reproduction was most frequently viviparous, but oviparous and ovoviviparous reproduction were also observed (Khalaf and Sokhansanj, 1993; Farid, 1994).

Four annual generations, two in winter and two in spring, were observed on weeping fig (Ficus benjamina) in Saudi Arabia, where populations were lowest in summer, probably due to high temperatures (Badawi and Al-Ahmed, 1990). In India, three generations a year were recorded (Glover, 1933).

Crawlers and female scales feed on dilute sap and surplus carbohydrate and nitrogen is converted into material to construct the scale cover, and not into honeydew as in other scale insect families.

Natural enemies

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Notes on Natural Enemies

Top of page Although A. orientalis has a wide distribution, its natural enemies have only been reported from a few countries, most notably India, Pakistan and Saudi Arabia (Rajagopal and Krishnamoorthy, 1996). In India, natural enemies were identified on a range of crops by Mani and Krishnamoorthy (1996). They recorded A. orientalis being parasitized by species of Aphytis on banana and custard apple (Annona reticulata), for example, but levels of parasitism were generally low.

Hayat (1986) listed a number of other parasitoids known to attack A. orientalis in the families Encyrtidae and Aphelinidae. Comperiella bifasciata and C. lemniscata are probably the only two parasitoids that are naturally effective at checking populations of A. orientalis over most of its range (Rajagopal and Krishnamoorthy, 1996).

Coccinellid beetles and lacewings are frequent predators of A. orientalis in a variety of crops (Mani and Krishnamoorthy, 1996).

Hyperparasites of the most common parasites of A. orientalis include Ablerus spp., Azotus spp., Marietta spp. and Zaomma spp. (Ofek et al., 1997).

Impact

Top of page A. orientalis is highly polyphagous and is therefore potentially a serious pest of a wide range of crops. It is considered to be a serious pest in certain areas of the world, notably on coconut and arecanut in South India (Rajagopal and Krishnamoorthy, 1996), and on coconut in Florida, USA (Dekle and Merrill, 1976).

The greatest economic impact attributed to A. orientalis is often in areas it has recently invaded. In Australia, for example, A. orientalis first spread from the Torres Strait Islands to Queensland in 1956. It caused problems for the first time in papaya during 1988, and is now the most important pest on papaya in northern Queensland (Elder et al., 1998).

It is an important pest of tamarind trees in India (Rajagopal and Krishnamoorthy, 1996), and of species of Citrus (especially Omani lime, sweet lime and grapefruit) in Iran (Farid, 1994) and Asia (Rosen, 1990). It is also a serious pest on coconuts in Malaysia and Sri Lanka, mango in the Philippines and Israel, papaya in Malaysia and Australia, and guava in India (Rosen, 1990). In Nigeria, Niger and northern Cameroon, A. orientalis infestations damage neem (Azadirachta indica) and can kill trees (Boa, 1995).

A. orientalis disrupts lac production, a resinous secretion from the insect Laccifer lacca collected in India and Indonesia, by feeding on the same hosts and thereby decreasing the purity and yield of the product (Rajagopal and Krishnamoorthy, 1996).

Detection and Inspection

Top of page Look for circular, flat, pale-yellow to reddish-brown scales on leaves, but sometimes on branches, trunks, shoots and fruits of host plants.

Similarities to Other Species/Conditions

Top of page A. orientalis is easily distinguished from most other Aonidiella species as the adult female's body is less heavily sclerotized and fails to become strongly reniform at maturity. It also has conspicuous submarginal groups of macroducts on either side of the free abdominal segments. However, it is similar to A. simplex and A. andersoni, although both these species lack perivulvar pores, which are present in A. orientalis females (McKenzie, 1938).

Prevention and Control

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Cultural Control

The pruning of lower stalks and water management can be useful in controlling A. orientalis (Khalaf and Sokhansanj, 1993) in Iran. In India, the cutting and burning of damaged shoots can keep A. orientalis populations under control in ber (Ziziphus mauritiana), whereas the removal and destruction of damaged tree parts can aid control during the early stages of infestation in tamarind (Rajagopal and Krishnamoorthy, 1996).

Damaging infestations on neem in West Africa are associated with water stress (Boa, 1995).

Biological Control

A. orientalis has been successfully controlled by three parasitoids on papaya in Queensland, Australia. Comperiella lemniscata was introduced from Hainan Island in China and from the Torres Strait in northern Queensland, and released during 1991. Within 12 months, parasitism rates rose as high as 80% and rejection of fruit for market dropped from 20-30 to 1-2%. Aphytis melinus was also augmentatively released and rates of parasitism were increased, although this parasitoid had to be continually re-released. Encarsia citrina occurred naturally, producing levels of up to 80% parasitism, and was also therefore important in the biological control of A. orientalis (Elder et al., 1998).

C. lemniscata and two predatory coccinellids, Chilocorus circumdatus and C. baileyii, were introduced into Israel from Australia for the control of A. orientalis on mango (Ofek et al., 1997). Rajagopal and Krishnamoorthy (1996) indicated the potential of the parasite Comperiella bifasciata and the predator Chilocorus nigrita as biological control agents.

Chemical Control

The usual chemical treatment is mineral oil sprays (Khalaf and Sokhansanj, 1993), although these are not routinely recommended as they interfere with the natural biological control of pest insects in orchards and plantations. Malathion, dimethoate or diazinon have also previously been recommended for dealing with severe infestations in papaya, tamarind and other crops (Rajagopal and Krishnamoorthy, 1996).

References

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Arriola Padilla VJ; Estrada Martínez E; Romero Nápoles J; González Hernández H; Pérez Miranda R, 2016. Scale insects (Hemiptera: Coccomorpha) on ornamental plants in greenhouses from the central zone of the Morelos state, Mexico. (Insectos escama (Hemiptera: Coccomorpha) en plantas ornamentales en viveros de la zona centro del estado de Morelos, México.) Interciencia, 41(8):552-560. http://www.interciencia.org/v41_08/indexe.html

Badawi A; Al-Ahmed AM, 1990. The population dynamics of the oriental scale insect, Aonidiella orientalis (Newstead) and factors affecting its seasonal abundance. Arab Gulf Journal of Scientific Research, 8(3):81-89.

Boa ER, 1995. A guide to the identification of diseases and pests of neem (Azadirachta indica). RAP Publication 1995/41. Bangkok, Thailand, FAO, 16-20, 34, 71 pp.

CIE, 1978. Distribution Maps of Pests, Map No. 386. Wallingford, UK: CAB International.

Costa EM; Godoy MS; Araujo EL; Silva RIR; Wolff VRdos S, 2013. First report of the infestation of Azadirachta indica A. Juss by Aonidiella orientalis (Newstead) (Hemiptera: Diaspididae) in Brazil. Bioscience Journal, 29(Supplement 1):1441-1445. http://www.seer.ufu.br/index.php/biosciencejournal/article/view/15088/13289

Dekle GW; Merrill GB, 1976. Florida armored scale insects. Arthropods of Florida and Neighbouring Land Areas No. 3. Gainesville, USA: Florida Department of Agriculture and Consumer Services, 32, 345 pp.

Elder RJ; Smith D, 1995. Mass rearing of Aonidiella orientalis (Newstead) (Hemiptera: Diaspididae) on butternut gramma. Journal of the Australian Entomological Society, 34(3):253-254; 6 ref.

Elder RJ; Smith D; Bell KL, 1998. Successful parasitoid control of Aonidiella orientalis (Newstead) (Hemiptera: Diaspididae) on Carica papaya L. Australian Journal of Entomology, 37(1):74-79; 11 ref.

Elwan AA, 2000. Survey of the insect and mite pests associated with date palm trees in Al-Dakhliya region, Sultanate of Oman. Egyptian Journal of Agricultural Research, 78(2):653-664.

Farid A, 1994. Study on bio-ecology and control of Aonidiella orientalis in Jiroft and Hormozgan. Applied Entomology and Phytopathology, 61(1/2):29, 96-105.

Glover PM, 1933. Aspidiotus (Furcaspis) orientalis Newstead, its economic importance in lac cultivation and its control. Indian Lac Research Institute Bulletin, 16:1-22.

Hayat M, 1986. Chalidoidea hosts. Host parasite list. Oriental Insects, 20:323-383.

Khalaf J; Sokhansanj M, 1993. Bioecological studies on orientalis yellow scale (Aonidiella orientalis New.) and its control by integrated methods in Fars province. Applied Entomology and Phytopathology, 60(1/2):53-59 (Persian), 11-12 (English).

Mani M; Krishnamoorthy A, 1996. Aonidiella orientalis (Newstead) (Diaspididae, Homoptera) and its natural enemies found on sapota, ber, custard apple and banana. Entomon, 21(3/4):273-274; 7 ref.

McKenzie HL, 1938. The genus Aonidiella (Homoptera: Coccoidea: Diaspididae). Microentomology, 3:1-36.

Muniappan R; Watson GW; Vaughan L; Gilbertson R; Noussourou M, 2012. New records of mealybugs, scale insects, and whiteflies (Hemiptera: Sternorrhyncha) from Mali and Senegal. Journal of Agricultural and Urban Entomology, 28(1):1-7. http://scentsoc.org/Volumes/JAUE/28/28001.pdf

Ofek G; Huberman G; Yzhar Y; Wysoki M; Kuzlitzky W; Reneh S; Inbal Z, 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; 8 ref.

Rajagopal D; Krishnamoorthy A, 1996. Bionomics and management of oriental yellow scale, Aonidiella orientalis (Newstead) (Homoptera:Diaspididae): an over view. Agricultural Reviews (Karnal), 17(3/4):139-146; 38 ref.

Rosen D, 1990. World Crop Pests. 4B. Armoured Scale Insects: their biology, natural enemies and control. Amsterdam, Netherlands: Elsevier Science Publishers, 688 pp.

Schotman CYL, 1989. Plant pests of quarantine importance to the Caribbean. RLAC-PROVEG, No. 21:80 pp.

Shafee SA; Fatma A, 1984. Taxonomic notes on Indian species of Echthroplexis Forster (Hymenoptera, Encyrtidae), with descriptions of two new species. Mitteilungen der Schweizerischen Entomologischen Gesellschaft, 57(4):371-376.

Shalaby FF; Hafez AA; Hamed AR; Morsi GA, 2000. Description and biological studies on Aspidiotiphagus citrinus Craw. (Aphelinidae: Hymenoptera) a new record parasitoid on Aonidiella orientalis (Newst.) in Egypt. Annals of Agricultural Science, Moshtohor, 38(1):531-544.

Verma SP; Dinabandhoo CL, 2005. Armoured scales (Homoptera: Diaspididae) associated with temperate and subtropical fruit trees in Himachal Pradesh. Acta Horticulturae, 696:423-426. http://www.actahort.org

Williams DJ; Watson GW, 1988. The Scale Insects of the Tropical South Pacific Region. Part 1. The Armoured Scales (Diaspididae). Wallingford, UK: CAB International.

Wysoki M, 1997. Present status of arthropod fauna in mango orchards in Israel. In: Lavi U, Degani C, Gazit S, Lahav E, Pesis E, Prusky D, Tomer E, Wysoki M, eds. Proceedings of the 5th International Mango Symposium, Volume 2. Acta Horticulturae, 455:805-811.

Distribution Maps

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