Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Upcoming Events

National Moth Week photos of insects and people. Here's how to add your images.

Photos of insects and people from the 2019 BugGuide Gathering in Louisiana, July 25-27

Discussion, insects and people from the 2018 gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Photos of insects and people from the 2012 gathering in Alabama

Photos of insects and people from the 2011 gathering in Iowa

Alder Buprestid - Eupristocerus cogitans

Alder Buprestid - Eupristocerus cogitans
Near Anthony, Greenbrier County, West Virginia, USA
June 29, 2005
An unusual Buprestid, with a red-purple metallic pronotum and white marks toward the rear of the elytra.

What size was it?
You're right, it is unusual.

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 Cresswell
Buckhannon, WV

No ID source
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.

Seems right for Eupristocerus cogitans
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 Cresswell
Buckhannon, WV

Comment viewing options
Select your preferred way to display the comments and click 'Save settings' to activate your changes.