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Entomology (Study of Bugs)/mystery small brown bugs


Mystery Bug
Mystery Bug  

Actual size, after I killed one
Actual size, after I k  
About three days ago I noticed some small spots crawling across my bedroom ceiling and working their way down my walls. They turned out to be small brownish bugs. They have small wings, so I know they are not bed bugs. It more like glided down my wall a little when I got close. They are about the size of a grain of rice or maybe a bit smaller. I found more yesterday and killed them. Today I found even more, so I investigated a little. It looks like they are mainly in my windowsill and around my window. I am renting an apartment, and I am concerned as to what these bugs are and if I should alert my leasing office. Please let me know what you think!

Thank you,

Hi, Tracey:

Thank you for including the images with your question.  It turns out they are not what I was expecting....

These are grain beetles in the flat bark beetle family Silvanidae.  They are among many kinds of insects recognized as "stored product pests."  They typically infest grains, grain products, and other pantry foods.  They can infest products before you purchase them, and/or infest items stored improperly.  Cardboard boxes and plastic bags offer no barrier to them.

Simply discard any infested items.  Store vulnerable foodstuffs in glass, metal, or durable plastic containers with tight-fitting lids.  This includes dry pet food.

Here is more information about these kinds of beetles.  I can't identify the species from your images, but all of them can be controlled in the same manner:

I am actually surprised and a bit disappointed that there are not more resources for the general public that are readily apparent in a Google search.  Shame on us entomologists.

Good luck with this, but don't worry about alerting your leasing office.  You might notify the grocer where you purchased the infested item if it turns out that is how you acquired these beetles.  Companies need to know if they are failing to control stored product pests.


Entomology (Study of Bugs)

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Eric R. Eaton


I answer insect and spider identification questions ONLY. Attach images if possible. No "what bit me?", "what do I feed this bug in captivity?", or science fair project questions please. NO TECHNICAL QUESTIONS ABOUT INSECT PHYSIOLOGY.


Principal author, Kaufman Field Guide to Insects of North America. Professional entomologist employed previously at University of Massachusetts, Chase Studio, Inc., and Cincinnati Zoo; contract work for West Virginia Department of Natural Resources, Smithsonian Institution, and Portland (Oregon) State University.

Author, Kaufman Field Guide to Insects of North America, Missouri Conservationist magazine, Ranger Rick, Birds & Blooms, Timeline (journal of the Ohio Historical Society). I have contributed to several books as well.

Oregon State University, undergraduate major in entomology, did not receive degree.

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One of the top 50 experts in all categories for, 2009.

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Principal author of the Kaufman Field Guide to Insects of North America, Smithsonian Institution (contract), Cincinnati Zoo (employer), Portland State University (contract), Chase Studio, Inc (employer), Arkansas Museum of Discovery (guest speaker). Currently seeking speaking engagements, leadership roles at nature festivals, workshops, and ecotours.

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