Once again I was remiss in not measuring. Maybe this season I will wear a mm ruler around my neck!

If we accept my ID, then the beetle must have been about 8 mm long. At least that is the length Tom Murray reported for the one he photographed. I just looked up the length in Peterson's Beetle Field Guide and White says 2 to 2.5 mm. That has got to be a misprint! Or is he saying the beetle's Alder gall is that size? Still seems small.

--Stephen

Stephen Cresswell
Buckhannon, WV
www.stephencresswell.com

I missed seeing any ID source in Tom's images. Perhaps Tom is wrong, White is right, and this is not Eupristocerus cogitans. Just a possibility.

This still seems right to me for Eupristocerus cogitans. It matches the picture in White, and in size 7-9 mm is about right for the little black silhouette White has put next to the E. cogitans picture to indicate the beetle's size. It does seem to me White has either made a mistake in saying 2 to 2.5 mm, or else he is saying 2 to 2.5 mm is the size of the gall (which seems like a small size for a gall).

Cedar Creek pictures the same beetle, though the white markings on the back are so weak as to be almost non-existant. The other BugGuide images of the species posted by Tom and Joyce seem to vary in the strength of these white markings.

By the way, I'm certain that the beetle pictured here was not as small as 2.5 mm. If it had been, my picture quality would have been poorer, particularly in a hand-held field shot like this one.

--Stephen

Stephen Cresswell
Buckhannon, WV
www.stephencresswell.com