Japanese+Beetle


 * __Japanese Beetle__**

Taxonomy: Kingdom: Anamalie Phylum: Arthropoda Class: Insecta Order: Coleoptra Family: Scarabaeidae Genus: Popilla Species: japonica

The Japanese beetle (//Popilla japonica//) is well known for its iridescent colored elytra. The name “Japanese beetle” comes from its native origin of Japan, these invasive pests were inadvertently transported from Japan to the US, they were first discovered in New Jersey in 1916. (1)

Fig. 1: Japanese beetle

Description: A defining feature of the Japanese beetle are the iridescent elytra, they can range in colors from metallic blue and green to a copper. The elytra of the beetle are just a little short of the end of the body; this helps identify the beetle from other species. The abdomen of the beetle is usually a dark brown or black, covered in small white tufts of hairs. Adults usually grow to be between 8mm- 12mm. Females tend to be larger then males; the difference between the sexes can be identified by the length and shape of the tibia. Males tend to have shorter sharper tibia then females. The larvae of the beetle is usually a gray to white, shaped like the letter C. (2)

Life Cycle: The beetles have a 1 year life cycle. Larvae that have fully matured will pupate by June, the adult beetles emerge from the ground between late June and early July, the first beetles out of the group release a that attracts the other adults to emerge from the ground. Females will begin mating with males almost immediately after emerging from the ground. The females may mate many times, when it’s time to lay the eggs they burrow about 2-4 inches and lay 1-5 eggs in the moist ground, this happens every 2 days or so. The female will have laid 40-60 eggs in one mating season. The eggs will hatch in a matter of a few days or a few weeks depending on the temperature and moisture level of the soil. Once hatched the grubs live underground burrowing deeper as the weather gets colder, maturing during June and repeating the cycle. (3)

Fig. 2: Japanese beetle life stages

Predators and Prey: Japanese beetles are polyphagous the “many things” eaters. The adult beetles will feed the leaves, flowers or fruit of nearly 300 species of plants. The ground dwelling larvae (also known as grubs) will eat the roots of different grasses, field crops and seedlings. The beetles are not native to the land therefore they don’t have any natural born predators in the US. The terrain in Japan is deemed unsuitable for larval development, which helps keeps the beetles at bay. The only predator in the US is humans trying to get rid of them to avoid huge losses in crops (2).

Ecological Importance and Human Impact: Japanese beetles are a non-native species that facilitate the native species injury on high value crops. Once a Japanese beetle has bitten a grape, the yeast it injects attracts more of the native June bugs to the crops. This leads too much higher amounts of crop damage and an elevation in pest status (1).

Japanese beetle quarantines are currently being held by the USDA-APHIS from states shipping from infested areas to uninfested areas. The progression of the beetle westward has been slowed but not stopped. There have been many forms of biological control to stop these beetles. They’re just diffuclt to get rid of because they have no natural born enemies. (3)

Created By Spitler, J.

References:
 * 1) 1. Hammons, Derrick L., Kurtural, Kaan S., Newman, Melissa C., and Potter, Daniel A. “Invasive Japanese Beetles facilitate aggregation and injury by a native scarab pest of ripening fruit.” //Proceedings of the National Academy of Science of the United States of America.// (2009) Vol.106(10), pp.3686-91. Web. 5 Nov. 2013 < [|www.pnas.org.ezproxy.uvm.edu/content/106/10/3686]>
 * 2) //2.// Capinera, John L. “Japanese Beetle, //Popillia japonica//” Encyclopedia of Entomology 2nd ed. Vol. 4. New York: Springer, 2008. 2049- 2051 Web. 5. Nov. 2013< []>
 * 3) 3. Shetlar, David J., “Japanese Beetle” //Ohio State University Extension Fact Sheet// (1991) HYG-2594-91, Web. 7 Nov. 2013 <[]>

Images: Fig. 1: Japanese beetle [Photograph] Retrieved 7 Nov. 2013, from <[]> Fig. 2: Japanese beetle life stages [Photograph]. Retrieved 7 Nov. 2013, from <[]>