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Whitespotted sawyer beetles out and about

Over the past week or so, biologists across Massachusetts and other New England states have reported seeing whitespotted sawyer beetles, the beetle most often confused with Asian longhorned beetle (ALB). The whitespotted sawyer (Monochamus scutellatus), a native beetle that attacks diseased and damaged pine trees, emerges from trees earlier in the season than ALB, which is not expected to be seen in Massachusetts until July.

Similar reports have been coming in via our ALB reporting form this week. Below is a photo, sent in today from Whitman, Massachusetts by Scott Pelletier, showing a whitespotted sawyer. This is a great shot of the beetle, making it easy for an expert to determine the species. Using the notes we’ve added that point out the tell-tale signs that this is a sawyer beetle, not ALB, you too can learn the difference between these two lookalikes:

(Click on the image to see it in full size)

If you see a longhorned beetle and are concerned that it might be ALB, it is always better to report it. For more information, check out this comparison of whitespotted sawyer and ALB.

(Below, for comparison: ALB – The real thing)I don't think that looks like me at all!

(Thanks to Scott for giving us permission to post his photo)

7 Responses | Add your Own

  • 1 db54 yazmış:

    Good article. In the Telegram & Gazette May 25th '09 edition are two great side by side pictures of the WSSB and the ALB. The former was discovered on my property. If you look at the B&W photo of an ALB there is a striking similarity. Upon magnification (as depicted in the article) and color the similarity stops. The problem is that ALB is the focus but it appears the WSSB can reek similar damage. In the Town of Douglas, there are lots of Pine/Conifer Trees. Minus a few dead ones in my front yard. The Good News is – NO ALB yet, The Bad News is – invasion by WSSB.

    what can be (or what is being) done about WSSB?

  • 2 Jennifer Forman Orth yazmış:

    As I mentioned in my email to you, it is obvious from your good photo that you have captured a whitespotted pine sawyer, not ALB. The easiest way to tell is to look at that distinctive white spot at the top center of the beetle's wing covers, as is pointed out in the photo in this blog post. Also, it is too early in the season to be finding adult ALBs, they do not emerge from the trees until mid-summer.

    Whitespotted sawyer is a native species, one of hundreds of different longhorned beetles that you may find in our state, but not a very common one. It typically attacks pine and fir trees that are already diseased or damaged and should not be a threat to a healthy pine stand.

  • 3 Michael Bohne yazmış:

    Great photo of the white spotted pine sawyer – one of the best I have ever seen!

  • 4 Anonymous yazmış:

    I stumbled across a long horned beetle in my driveway yesterday afternoon – and after comparing it to the photos, I'm guessing it's a WSSB. I was fearful it was a ALB, but the wing covers are not shiny. Thanks for the great pics to compare to – I'm breathing a little easier.

  • 5 Jennifer Forman Orth yazmış:

    Late in October, there are very few beetles around in Massachusetts (other than the Asian multicolored lady beetle). If you're seeing big, beefy insects around the house, particularly on light-colored houses, windows screens, etc., it is much more likely to be a Western conifer seed bug. You can find out more about them here:

  • 6 gus schultz yazmış:

    Are they really in Hyde Park?

  • 7 jformanorth yazmış:

    Asian longhorned beetle has not been found in Hyde Park. They have been found in the Jamaica Plain section of Boston and in the Greater Worcester area. A boston map can be found here.