Subject: need identification
Location: santa rosa, ca
July 13, 2012 12:05 am
Love to know what this bug is..
Signature: marion

Banded Alder Borer

Hi Marion,
While it might not be appropriate for the staff of What’s That Bug? to have favorites, the Banded Alder Borer,
Rosalia funebris, in your photograph is probably our favorite North American Beetle.  The Banded Alder Borer is found in the western states from California to Washington, into Canada.  BugGuide also has reports from Idaho and Utah.

Thank you so much for your quick reply.  We are so impressed with this bug. The one you see the photo of is the male.
A few minutes later another larger one appeared, which turned out to be the female.  The smaller one reacted instantly by mating the with larger beetle.  Thank you again.
Marion and Kent

Hi Marion and Kent,
You are such teasers to tell us that information and then not send a photo.  It is also very curious that the female found the male.  It is generally believed that female insects release pheromones and males are attracted to the “scent” of the females by using their more developed antennae.  Sometimes both sexes are attracted to other scents or to food supplies and mating takes place at a jointly attractive location.  Charles Hogue writes in Insects of the Los Angeles Basin:  “Adults may be attracted to the volatilizing esters in fresh paint.”  We hope you took a photo of the mating activity that you can send to us.

Location: California

7 Responses to Banded Alder Borer

  1. Aaron Neerenberg says:

    I work in Hillsboro, Oregon. Our facility has been undergoing repainting the last week. I saw these (for the first time in my life) on Tuesday. Further reinforcement for the comment by Charles Hogue 🙂

  2. Cara Mengwasser says:

    Just saw one of these Banded Alder Borer in West Alton, Missouri at the Riverlands Migratory Bird Sanctuary. Impressive looking bug! I’ve never seen this bug before today.

    • bugman says:

      Are you certain you saw a Banded Alder Borer? According to BugGuide, they have not been reported east of Utah, and Missouri is considerably east of Utah. There are many other members in the family that superficially resemble the Banded Alder Borer, however it is quite a distinctive species. We wish you had a photo to document the sighting.

  3. Beth says:

    We just found one of these in some older logs in our field. We took pictures but can’t get them to post here.
    We live near Port Orchard, Wa.

  4. Terry Schoeppe says:

    Saw one tonight in Fort Smith AR
    I have never seen one

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