Entomology (Study of Bugs)/Weird bug


Found this bug today in our backyard on my sons playscape.  It is about the size of a dollar coin.
emailing from Toronto, Ontario.

Is it something to be worried about?  Can it destroy trees and wood like termites.

Thank you,


Dear Jason - This is the shed exoskeleton ('shell') of a cicada nymph; likely a Tibicen species. Commonly known as dog-day cicadas or harvestflies, these insects spend he majority of their lives underground, feeding on the sap from tree roots. When fully grown (usually after two to eight years), they emerge from the ground, climb up on some handy object, and complete their metamorphosis to the adult form - see http://tinyurl.com/cvy5wux for an image of an adult. Female cicadas insert their eggs under the bark of twigs/small branches of trees, this sometimes results in the death of the branch beyond the oviposition site if the bark is completely girdled - see http://tinyurl.com/brm2386 for an image. Fortunately, this seldom causes serious harm to the trees.
Hope this helps,

Entomology (Study of Bugs)

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Ed Saugstad


Will accept most questions in general entomology, including those related to medical entomology, taxonomy, ecology, arthropod surveillance, and pest management. If you are requesting a 'mystery bug' identification, PLEASE either attach an image to your question, or post an image on a web page (such as Flickr) so that I can look at it, as verbal descriptions frequently are insufficient for a definitive identification.


21 years in the U.S. Army as a medical entomologist; duties varied from surveillance of pest populations (including mosquitoes, cockroaches, ticks, and stored products pests) to conducting research on mosquito-virus ecological relationships and mosquito faunal studies. Ten years as a civilian analyst for the Department of Defense, primarily on distribution of vector-borne diseases worldwide. Limited experience on surveillance of agricultural insects in North Dakota and Indiana.

Entomological Society of America, West Virginia Entomological Society, Society for Vector Ecology, National Speleological Society, West Virginia Association for Cave Studies.

American Journal of Public Health, Contributions of the American Entomological Institute, Japanese Journal of Sanitary Zoology, Journal of Economic Entomology, Mosquito News, and Mosquito Systematics.

B.S. in entomology from North Dakota State University in 1963, M.S. in entomology from Purdue University in 1967.

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