Protaetia orientalis

Status

Pest

Common name(s)

oriental flower beetle, Asian flower beetle

Taxonomy

Family: Scarabaeidae Subfamily: Cetoniinae Genus: Protaetia Species: Protaetia orientalis (Gory and Percheron, 1833)

DNA barcode

none available

Adult diagnosis

Total body length 19.9–26.8 mm (0.78–1.1 in). Body broadly oval; dorsoventrally flattened. Color shiny black, rarely shiny greenish; elytraelytra:
the hardened and chitinous wing-cover of a beetle that protect and overlie the flight wing
with prominent to indistinct pale markings. Clypeusclypeus:
part of the head anterior to the frons; the most anterior portion in dorsal view
broad, anterioranterior:
the front or forward; opposite of posterior
margin entire to sinuatesinuate:
gently curved (specifically of margins or edges); often in reference to the clypeus
. Front tibiatibia:
a segment of the leg articulated with the tarsus and femur
of male with 2 or 3 external teeth (third toothtooth:
a pointed process from an appendage or margin, often in reference to the tibia
weak); female with 3 external teeth. Hind tibiatibia:
a segment of the leg articulated with the tarsus and femur
with 2 lateral ridges. ElytraElytra:
the hardened and chitinous wing-cover of a beetle that protect and overlie the flight wing
lacking apical spine in both sexes.

Larval diagnosis

Undescribed in English. For Cetoniinae (Ritcher, 1966Ritcher, 1966:
Ritcher P. 1966. White grubs and their allies: a study of North American scarabaeoid larvae. Oregon State University Monographs, Studies in Entomology 4: 1-219.): Like other Protaetia species, when alive, larvaelarvae:
the immature form of an insect; in scarabs, also called grub or white grub; preceded by the egg stage, followed by the pupal stage
crawl on their backs with their legs up, and they feel distinctly "squishy" rather than firm (a characteristic of coconut rhinoceros beetle [Oryctes rhinoceros] larvae). Grub C-shaped, not hump-backed, cylindrical, whitish. Maxillamaxilla:
set of paired mouthparts located posterior to the mandibles
with galeagalea:
outer branch or lobe of the maxilla
and lacinialacinia:
inner portion of the maxilla
fused, or nearly so. Labrumlabrum:
upper lip that covers the mandibles and is located ventrally relative to the clypeus
symmetrical. Claws of hind leg large, cylindrical, and hairy. Abdominal segments 9 and 10 fused. Anal opening transversetransverse:
extending horizontally across a surface
, straight to slightly curved.

Native range

East Asia. Protaetia orientalis is a native of East Asia (LeBlanc et al., 2013LeBlanc et al., 2013:
Leblanc L, Graham S, Pohlman K, Fujita B. 2013. Protaetia orientalis (Coleoptera: Scarabaeidae) attracted to methyl eugenol fruit fly lure. Proceedings of the Hawaiian Entomological Society 45: 45–48. full text (accessed 2015)), ranging from China to Korea and Japan (Marler and Muniappan, 2006Marler and Muniappan, 2006:
Marler T and Muniappan R. 2006. Pests of Cycas micronesica leaf, stem, and male reproductive tissues with notes on current threat status. Micronesica 19: 1-9. full text (accessed 2015)).

Plant host(s)

Adults of this species are generalist frugivores and are associated with the flowers and overripe or damaged fruit of 42 recorded plant species in 25 families (Ijima and Takeuchi, 2007Ijima and Takeuchi, 2007:
Ijima K, Takeuchi M. 2007. Life history of Protaetia orientalis (Coleoptera: Scarabaeidae) in the Kanto District; and food resource plants of P. orientalis in Japan. Japanese Agricultural Science, Tokyo University of Agriculture 52: 89–96.). Commercially important among these are papaya (Carica papaya), coconut (Cocos nucifera), mango (Mangifera indica), banana (Musa spp.), sorghum (Sorghum bicolor), and corn (Zea mays). Additionally, the Asian flower beetle is known to opportunistically feed from sap flows (Ijima and Takeuchi, 2007Ijima and Takeuchi, 2007:
Ijima K, Takeuchi M. 2007. Life history of Protaetia orientalis (Coleoptera: Scarabaeidae) in the Kanto District; and food resource plants of P. orientalis in Japan. Japanese Agricultural Science, Tokyo University of Agriculture 52: 89–96.). In Guam, this species is a minor pest of the endangered Micronesian cycad (Cycas micronesica) (Marler and Muniappan, 2006Marler and Muniappan, 2006:
Marler T and Muniappan R. 2006. Pests of Cycas micronesica leaf, stem, and male reproductive tissues with notes on current threat status. Micronesica 19: 1-9. full text (accessed 2015)). LarvaeLarvae:
the immature form of an insect; in scarabs, also called grub or white grub; preceded by the egg stage, followed by the pupal stage
are not plant pests and subsist on organic soil debris and compost (Kim et al., 2002Kim et al., 2002:
Kim C, Lee S, Go M, Park K. 2002. Ecological characteristics of Protaetia orientalis submarmorea (Burmeister) (Coleoptera: Cetoniidae). Korean Journal of Applied Entomology 41: 43-47. [in Korean]), as is typical of many cetoniine scarab larvaelarvae:
the immature form of an insect; in scarabs, also called grub or white grub; preceded by the egg stage, followed by the pupal stage
(Ritcher, 1966Ritcher, 1966:
Ritcher P. 1966. White grubs and their allies: a study of North American scarabaeoid larvae. Oregon State University Monographs, Studies in Entomology 4: 1-219.).

Life history

(Kim et al., 2002Kim et al., 2002:
Kim C, Lee S, Go M, Park K. 2002. Ecological characteristics of Protaetia orientalis submarmorea (Burmeister) (Coleoptera: Cetoniidae). Korean Journal of Applied Entomology 41: 43-47. [in Korean]): In Korea, adults are active from April until October, with peak abundance occurring in July and August. LarvaeLarvae:
the immature form of an insect; in scarabs, also called grub or white grub; preceded by the egg stage, followed by the pupal stage
overwinter in the final instarinstar:
in scarabs, one of the three larval growth phases (i.e., first instar, second instar, third instar), each ending with the larvae molting to the next phase
, with pupation occurring in the following spring. The first larval instarinstar:
in scarabs, one of the three larval growth phases (i.e., first instar, second instar, third instar), each ending with the larvae molting to the next phase
lasts an average of 10.6 days, the second instarinstar:
in scarabs, one of the three larval growth phases (i.e., first instar, second instar, third instar), each ending with the larvae molting to the next phase
18.7 days, the final instarinstar:
in scarabs, one of the three larval growth phases (i.e., first instar, second instar, third instar), each ending with the larvae molting to the next phase
38.1 days, and pupation averaged 35.5 days. Female adults live an average of 135.2 days, during which an average of 82.8 eggs were laid. LarvaeLarvae:
the immature form of an insect; in scarabs, also called grub or white grub; preceded by the egg stage, followed by the pupal stage
feed on organic soil debris. Adults of this species are diurnaldiurnal:
active during daylight hours
and may be found feeding or actively flying at midday, particularly on warm, sunny days. It is not clear that Hawaiian or Guamanian populations of the Asian flower beetle show the same strong seasonal patterns that are observed in Korea. In Guam, museum specimens provide evidence that adults are found throughout the year.

Pest potential

Moderate. Like the Midway emerald beetle (Protaetia pryeri), this species can often be found in large feeding aggregations on fruit. While the sight of these aggregations may be alarming for plant owners, they rarely cause significant damage to healthy fruit; instead, beetles prefer overripe or already damaged fruits, perhaps attracted to the odors of fermentation (LeBlanc et al., 2013LeBlanc et al., 2013:
Leblanc L, Graham S, Pohlman K, Fujita B. 2013. Protaetia orientalis (Coleoptera: Scarabaeidae) attracted to methyl eugenol fruit fly lure. Proceedings of the Hawaiian Entomological Society 45: 45–48. full text (accessed 2015)). Beetles are, however, capable of causing a degree of mechanical damage to surrounding healthy fruits or flowers with their sharp tarsal claws when they clamber towards fruit (LeBlanc et al., 2013LeBlanc et al., 2013:
Leblanc L, Graham S, Pohlman K, Fujita B. 2013. Protaetia orientalis (Coleoptera: Scarabaeidae) attracted to methyl eugenol fruit fly lure. Proceedings of the Hawaiian Entomological Society 45: 45–48. full text (accessed 2015)).

Status in Hawaii

Established. The first record of this species dates to 1952, when a live specimen was found on an aircraft flying into Hickam Air Force Base from Japan (Hawaiian Entomological Society, 1952AHawaiian Entomological Society, 1952A:
Anonymous. 1952A. Proceedings of the Hawaiian Entomological Society for the year 1952. Proceedings of the Hawaiian Entomological Society 15: 1-20. full text (accessed 2015)). USDA APHIS records show further quarantine interceptions from Air Force aircraft arriving from Andersen Air Force Base in Guam in the 1980's and 90's (Moore, 2012Moore, 2012:
Moore A. 2012. Guam as a source of new insects for Hawaii. Pacific Entomology Conference, Portland, Oregon 2012. Available from http://guaminsects.myspecies.info/sites/guaminsects.myspecies.info/files/GuamHawaiiBugConnection.pdf (accessed 2015).). However, populations did not become established on Oahu until 2002. The species reached Maui in 2010 and Big Island in 2013 (LeBlanc et al., 2013LeBlanc et al., 2013:
Leblanc L, Graham S, Pohlman K, Fujita B. 2013. Protaetia orientalis (Coleoptera: Scarabaeidae) attracted to methyl eugenol fruit fly lure. Proceedings of the Hawaiian Entomological Society 45: 45–48. full text (accessed 2015)).

Status in Guam

Established. This species has been present in Guam since the 1970's (LeBlanc et al., 2013LeBlanc et al., 2013:
Leblanc L, Graham S, Pohlman K, Fujita B. 2013. Protaetia orientalis (Coleoptera: Scarabaeidae) attracted to methyl eugenol fruit fly lure. Proceedings of the Hawaiian Entomological Society 45: 45–48. full text (accessed 2015)) and is now one of the more common and visible scarabs on the island.

Potential distribution and dispersal pathway

Adults of this species have an established history of hitchhiking aboard military aircraft (Moore, 2012Moore, 2012:
Moore A. 2012. Guam as a source of new insects for Hawaii. Pacific Entomology Conference, Portland, Oregon 2012. Available from http://guaminsects.myspecies.info/sites/guaminsects.myspecies.info/files/GuamHawaiiBugConnection.pdf (accessed 2015).). As such, United States Air Force bases in California and Florida should be regarded as very likely sites of future introductions. Indeed, in California this species was intercepted in quarantine at San Mateo in 2003 (Gaimari, 2005Gaimari, 2005:
Gaimari S (editor). 2005. California plant pest amp; disease report. California Department of Food and Agriculture, Plant Pest Diagnostics Branch 22: 52 (July 2002-July 2005).) and is now regarded as a class A pest species (Cosner, 2013Cosner, 2013:
Cosner C. 2013. Invasive species pathway risk analysis for California. PhD dissertation, University of California, Davis, California. full text (accessed 2015)). Further, because adults are attracted to fermenting fruits and nectar-bearing flowers, it is possible that the Protaetia orientalis could hitchhike on nursery plants. Adults could also be accidentally spread in shipments of commercially grown fruits.

Similar species

This beetle is one of the three species in the genus Protaetia known from Hawaii and Guam. The remaining two species are Protaetia pryeri and Protaetia fusca. These three species are separated by size (P. orientalis at 19.9–26.8 mm [0.78–1.1 in] versus P. fuscaat 12.0–17.0 mm [0.47–0.67 in]), examination of the elytral apices (P. orientalis and P. pryeri always without apical spines versus P. fuscawith apical spines in the male), and hind tibiatibia:
a segment of the leg articulated with the tarsus and femur
(P. orientalis with 2 lateral ridges versus P. fuscaand P. pryeriwith a single lateral ridge).

Other names (synonyms)

Cetonia orientalis Gory and Percheron, Calopotosia orientalis (Gory and Percheron), Protaetia aereta Erichson, Protaetia speculifera Schauman

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