Mango Shield Scale | Pest Rating Proposals and Final Ratings

California Pest Rating for

Milviscutulus mangiferae (Green): Mango Shield Scale

Hemiptera: Coccidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Since 1991 Milviscutulus mangiferae has been regularly intercepted by CDFA’s border stations and dog teams. This scale insect presently has a temporary rating of “Q”. A pest rating proposal is needed to establish a permanent pest rating.

History & Status:

Background: Milviscutulus mangiferae is a highly polyphagous scale insect that feeds on a wide variety of plants. Known hosts include: Anacardiaceae: Campnosperma brevipetiolata¹, Gluta turtur¹, mango (Mangifera indica¹, Mangifera sp.¹); Annonaceae: susung-kalabaw (Uvaria rufa¹); Apocynaceae: Adenium sp.², Alstonia spectabilis¹, Alyxia sp.², Plumeria sp.¹, yellow oleander (Thevetia peruviana¹); Araceae: elephant ear (Caladium sp.¹), Colocasia sp.², Diffenbachia sp.², Epipremnum sp.¹; Araliaceae: Meryta macrophylla¹, Schefflera sp.¹; Arecaceae: Chamaedorea sp.², coconut (Cocos nucifera¹), fruit salad plant (Monstera deliciosa¹); Asparagaceae: ti (Cordyline terminalis¹), Cordyline fruticosa¹; Dracaena sp.²; Asteraceae: Wedelia biflora¹; Bignoniaceae: Spathodea sp.²; Bixaceae: achiote (Bixa orellana¹); Boraginaceae: Cordia myxa¹; Bromeliaceae: pineapple (Ananas sp.¹); Caricaceae: papaya (Carica papaya¹); Combretaceae: Terminalia complanata¹, Terminalia brassii¹, tropical almond (Terminalia catappa¹); Convolvulaceae: woodrose (Merremia sp.¹); Elaeocarpaceae: Elaeocarpus sp.¹; Euphorbiaceae: Breynia cernua¹, croton (Codiaeum variegatum¹); Pimelodendron amboinicum¹; Fabaceae: Gliricidia sp.¹; Flagellariaceae: Flagellaria sp.¹; Gnetaceae: paddy oats (Gnetum gnemon¹); Lauraceae: cinnamon (Cinnamomum sp.¹); Chinese cinnamon (Cinnamomum cassia¹), cinnamon (Cinnamomum zeylanica¹), Laurus sp.², Litsea zeylanica¹, avocado (Persea americana¹); Malpighiaceae: wild crapemyrtle (Malpighia glabra¹); Malvaceae: Hibiscus sp.¹; Meliaceae: Lansium sp.²; Moraceae: jackfruit (Artocarpus integrifolia¹), Artocarpus sp.¹, breadfruit (Artocarpus altilis¹), jackfruit (Artocarpus heterophyllus¹), Artocarpus integra¹, Hauli tree (Ficus septica¹), Ficus sp.¹; Ficus gibbosa¹, Ficus glandulifera¹, Ficus theophrastoides¹, dye fig (Ficus tinctoria¹), lechechiva (Pseudolmedia havanensis¹); Musaceae: banana (Musa sp.²); Myristicaceae: Gymnacranthera sp.¹, nutmeg (Myristica moschata¹); Myrtaceae: Callistemon sp.², Decaspermum sp.¹, lemon eucalyptus (Eucalyptus citriodora¹), rainbow eucalyptus (Eucalyptus deglupta¹), malay apple (Eugenia malaccensis¹), clove (Eugenia caryophyllata¹), rotra (Eugenia jambolona¹), jambos (Eugenia jambos¹), Eugenia parkeri¹, Eugenia sp.¹, rose apple (Eugenia aquea¹), white stopper (Eugenia axillaris¹), Jambosa sp.¹, myrtle (Myrtus sp.²), common guava (Psidium guajava¹), costa rican guava (Psidium friedrichsthalianum¹), rose myrtle (Rhodomyrtus tomentosa¹); Oleaceae: Jasminum trifoliatum¹; Opiliaceae: false olive (Champereia manillana¹); Orchidaceae: alien orchid (Dendrobium spectabile¹), vanilla (Vanilla sp.¹); Phyllanthaceae: bishop wood (Bischofia javanica¹); Pittosporaceae: Pittosporum sp.²; Primulaceae: Parathesis cubana¹, Rapanea quianensis¹; Rhizophoraceae: Gynotroches axilaris¹, Rhizophora apiculata¹, red mangrove (Rhizophora mucronata¹); Rosaceae: Rosa sp.²; Rubiaceae: Bouvardia sp.², Gardenia florida¹, jungle geranium (Ixora coccinea¹), noni (Morinda citrifolia¹), Platanocephalus chinensis¹, Platanocephalus morindaefolius¹, Psychotria elyptica¹, Psychotria rubra¹, Timonius sp.¹; Rutaceae: lemon (Citrus limon¹), orange (Citrus sinensis¹); Sapindaceae: ackee (Blighia sapida¹), Dimocarpus sp.², Guioa sp.¹; Sapotaceae: Palaquium formosanum¹, Pometia pinnata¹; Solanaceae: Cuban raintree (Brunfelsia nitida¹); Strelitziaceae: Strelitzia sp.¹; Verbenaceae: Vitex pubescens¹; Zingiberaceae: ginger (Zingiber sp.). Milviscutulus mangiferae may spread long distances on infested plants and plant material from this extensive host list.

Worldwide Distribution: Milviscutulus mangiferae is widespread in the Australasian, Afrotropical, Oriental, and Neotropical regions¹. It has also been found in Israel¹, Japan¹, and Hawaii¹. In North America the scale has been found in Mexico, Florida, and Texas¹.

Official Control: Milviscutulus mangiferae is considered a quarantine pest by Japan and the Republic of Korea³.

California Distribution: Milviscutulus mangiferae has never been found in the environment of California.

California Interceptions: Milviscutulus mangiferae has been regularly intercepted by CDFA since 1991, most commonly on shipments of mango (Mangifera indica) and ti leaves (Cordyline terminalis) from Florida and Hawaii. The scale insect was found on Schefflera sp. plants at a nursery in Oxnard (Ventura County) in 2003 (PDR 1266877). It was found on mango and cherimoya plants at a nursery in Bonita (San Diego County) in October 2013 (PDRs 370P06143908, 370P06143909, 370P06144251, 370P06144252, 370P06144253) and again May 2014 (PDRs 370P06228020, 370P06228022).

The risk Milviscutulus mangiferae (mango shield scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: The distribution of Milviscutulus mangiferae is primarily tropical. However, it is found in at least one nation with a Mediterranean climate similar to that of California (Israel¹). Host plants are commonly grown in the warmer parts of California and the scale insect is likely to establish in these areas. Milviscutulus mangiferae receives a Medium(2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Milviscutulus mangiferae feeds on a wide variety of plants in at least 44 plant families. It receives a High(3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Milviscutulus mangiferae has a high reproductive rate and three generations per year¹. Scales may be moved long distances in commerce of infested plants or plant parts and may be dispersed locally by wind or by hitchhiking on clothing, animals, or equipment. Milviscutulus mangiferae receives a High(3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Milviscutulus mangiferae can damage fruit by contaminating it with honeydew, leading to the growth of sooty mold⁴. Heavy infestations may reduce plant vigor and leaf size, causing yellowing of leaves, leaf drop, and dieback⁴. This damage could reduce fruit yields. The presence of this scale may increase production costs in orchards and nurseries as some growers are likely to treat. The scale insect also has the potential to disrupt markets by disfiguring citrus and avocado fruit as well as nursery stock. Milviscutulus mangiferae receives a High(3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Milviscutulus mangiferae is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It may feed on the endangered small-leave rose (Rosa minutifolia). The scale is not expected to disrupt critical habitats. It may trigger additional private treatment programs by fruit production and nursery industries and by residents who find infested plants unsightly. Milviscutulus mangiferae feeds on a wide variety of plants that are grown as ornamentals and, in the absence of its natural enemies, may have a significant impact on them. The scale receives a High(3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Milviscutulus mangiferae (mango shield scale): High(14)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Milviscutulus mangiferae has never been detected in the environment of California and receives a Not established(0) in this category.

Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High(14)

Uncertainty:

It is possible that this insect will be managed by existing management practices in fruit production and nursery industries.

Conclusion and Rating Justification:

Milviscutulus mangiferae has not been found in the environment of California. Its entry into the environment of the state may have significant economic and environmental impacts. An “A” rating is justified.

References:

¹Miller, Dug, Yair Ben-Dov, Gary Gibson, and Nate Hardy. ScaleNet.

http://scalenet.info/catalogue/Milviscutulus%20mangiferae/

²SEL Catalog.

http://idtools.org/id/scales/factsheet.php?name=6894

³USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

⁴Grimshaw, Judy F. and John F. Donaldson. 2007. New records of mango shield scale Milviscutulus mangiferae (Green) (Hemiptera: Coccidae) and Brevennia rehi (Lindinger) (Hemiptera: Pseudococcidae) in north Queensland. Australian Journal of Entomology 46: 96-98. http://hbs.bishopmuseum.org/fiji/pdf/grimshaw-donaldson2007.pdf