Yellow Douglas Fir Borer

Subject: california beetle
Location: Black Point, Novato, California
August 9, 2012 2:18 pm
Three of these have come into our house in Northern California in the evenings this August. The closest I could come to identifying is to some kind of blister beetle.
Signature: Ruth Corwin

Yellow Douglas Fir Borer

Hi Ruth,
This is not a Blister Beetle.  It is a Longhorned Borer Beetle in the family Cerambycidae.  In June, we posted our first photos of the Yellow Douglas Fir Borer, and at that time it took us a bit of time to track down its identity.  The Oregon State University Insect ID Clinic website states:  “This is a common long horned beetle in the west that feeds under the bark of Douglas-fir as a larva. The black spots on the sides of the beetle distinguish it from some of the other species that occur in Oregon .”

Thank you, Daniel, for the identification. The black spots are very clear.
And thank you for the link to the post at your site. We’re at the opposite end of the Douglas Fir range from LL in Canada, at the southernmost extension with a zone of these firs in Marin County.  My house at the mouth of the Petaluma River is maybe 12 miles west of the nearest area. It’s a little surprising to see these bugs on the edge of San Francisco Bay.
Your help is much appreciated.
All the best.
Ruth Corwin

 

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