black and white bug
Location: Parksville, BC.
August 19, 2011 9:13 pm
Parksville, BC.
august 19 2011.
it is about an inch and a half long
thanks very much
Signature: anon125

Banded Alder Borer

Dear anon125
This beautiful creature is known as a Banded Alder Borer or California Laurel Borer,
Rosalia funebris, and BugGuide indicates is is found in the:  “Western United States plus British Columbia and Alaska.”  The larvae are Flatheaded Borers in dead hardwood trees including maple, alder, oak, willow and other hardwoods according to BugGuide, and Charles Hogue in his book Insects of the Los Angeles basin also adds ash and eucalyptus.  The Banded Alder Borer is not considered to be a harmful species.  The Washington State University Cooperative Extension webpage written by entomologist Arthur L. Antonelli adds:  “The adults usually are encountered singly in summer, but occasionally they are attracted in numbers to fresh paint.”  Hogue made a similar comment.  A European relative known as the Blue Rosalia, Rosalia alpina, is considered an endangered species and it has been featured on the postage stamps of several European countries including this beautiful example of a German stamp from 1993.  We don’t believe the Banded Alder Borer has ever appeared on a stamp.

Blue Rosalia on a German Postage Stamp

Thanks very much
it was on fresh paint – elastomeric paint.


Location: Canada

13 Responses to Banded Alder Borer

  1. Nikole says:

    This is exactly the bug that I had found thank you for your help it is a very cool bug!

    • bugman says:

      Hi Nikole,
      We are happy to learn we correctly identified your Banded Alder Borer based on your vivid description. Sadly, our readers never read your original email to us, so we are reproducing it below.

      Subject: A weird bug
      Location: Longview, Washington
      April 24, 2013 9:02 am
      I found a bug in my yard one day as I was leaving for work and was unable to catch a photo of it but it was about 1 1/2 inches to 2 inches round it had lots of antennas and wings and was black and white zebra striped and it kinda of looked like a lion fish. … Can you please let me know if you have any idea what these kind of bugs are? Sorry I have no photos. …
      Signature: Nikole Rodriguez

  2. Karen says:

    Can they cause harm to a dog?

  3. Andria says:

    Do they shoot stinky smells like a stink bug? We found one in the yard today and my son accidentally splashed water on it. It stuck its but up in the air like it was going to spray! haha

  4. Kathryn says:

    This is so interesting–I just found one on our freshly painted deck. I wonder why they are attracted to fresh paint? I saw that this could be true on Bug Guide, then Googled it for more info and found this thread. It’s so interesting as ours was also on freshly painted deck with elasomeric paint as well, as the first person posted. There must be a smell that they like?

  5. mike miller says:

    I’ve lived on the same forested property for 25 years and never seen one. Some 6 weeks ago, I felled a dozen Doug Fir & Western Red Cedar. Today I found one of these (Banded Alder Borer) on my deck.
    As far as the “fresh paint” smell as an attractant: Fresh paint can smell remarkably similar to fresh-cut wood (especially cedar). Perhaps it gives off a similar chemical. I’m not sure that’s the answer, but that’s the truth.

  6. Anita Scouten says:

    Very happy to come across this page. Quite some time ago, I will say roughly the summer of 2003 or 2004, my husband had painted the apartment complex we were managing in Nanaimo B.C. with elastomeric paint and the next day there were hundreds of these beetles all over the building and shrubs. I had never seen them before or since. This answered my question as to why they came out that time.

    • bugman says:

      Thanks for providing a first person account of the Banded Alder Borer’s attraction to paint fumes.

  7. Leeloo says:

    Just found one in Croatia 😀

  8. Sam says:

    Just found one on Seattle WA on a blue tarp, what a interesting find. Two summers ago Antlions appeared in a brick planter in front of the house.I fed them a few ants and a few other insects they left after some te never returned.

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