Entomology (Study of Bugs)/beetles


beetle backside
beetle backside  

beetle bellyside
beetle bellyside  
I have found two of these beetles near my house.  The first one was dying on the front porch and the second was dead on the back patio. Found both within about six weeks of each other. I found one of your Q&A's from 2009 identifying it as a woodboring beetle found in dead/dying pine or Conifers. (I live in Oregon and have never seen these before) . Do I need to worry about an infestation in my home? I do not believe the are originating from my yard.


Thank you for including the images with your question, but the question says it is from Colorado, and now you state you live in Oregon, so I wonder where exactly you found the specimens.

This is a female "Ponderous Borer," Trichocnemis spiculatus , a member of the longhorned beetle family Cerambycidae:


The species is found in both Oregon and Colorado.  I'm jealous because I lived in Oregon for the first 27 years of my life and never once saw one of these giants.  I've been in Colorado for the last three years, and still not seen one here, either. :-(

This is NOT a pest species.  It will not bore into your home, or kill any trees.  The beetles only attack dead, dying, or severely-weakened trees.


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 AllExperts.com, 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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