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Entomology (Study of Bugs)/tiny reddish black beetles that seem to be coming from an inside wall


Hello, I had these same beetles last summer and when it got cold, they disappeared.  They seem to be coming from an inside wall and this summer they come out >1000 every day.  My vacuum is almost worn out.  They do fly but not very often.  I have tried 5 different insecticides both last summer and this summer; and had them professionally sprayed this summer twice.  I have a feeling we need to kill them in the wall.  They are coming from the countertop that is abutting (sp?) an inside wall.  I live in a condo and my upstairs neighbors do not have them.  Please help me!

Dear Antoinette - I hesitate to state with any certainty without actually being able to see your unwanted house guests, but I suspect that they might be foreign grain beetles (). Also known as 'new house beetles,' they are nuisance pests that do no real harm. See for a fact sheet on these beetles to see if the description matches what you have. However, if after reviewing this publication you believe that you have something different, I suggest that you place some of them in a small container of rubbing alcohol and take them to your county office of the University of Minnesota's Cooperative Extension Service (see for links to contact information) to see if someone there can be of assistance. Extension service offices usually are a good resource when dealing with most home/yard/garden pest problems.

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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