Download high resolution image here.

This subject came to a mercury vapor lamp set-up at 33°22'01.3N 108°04'23.4W, 6846 ft elevation, Wall Lake 7.5' quadrangle, about 1.5 miles north of Wall Lake near State Route 61 (Forest Road 150), Gila National Forest, Catron Co., NM. Many other images from this event are posted. I collected representative specimens of most, and can follow up with high resolution images of selected ones if needed.

These images display all the key features in Arnett's Histeridae key to genra (1), identifying this as Acritus. It is similar another specimen posted, also only to genus. This one is more densely punctate and the reticulation patterns on the pygium and head differ, though. I was unable to locate a key to species for this genus.

These images, except for the last image, are contrast enhanced and sharpened to better visualize key feature by use of Method C, as described in the Helicon Focus Help manual, and subsequent adjustments to the light levels and sharpness with Photoshop Elements.

This image is from a Helicon Focus processed stack of 262 images with a 2.7 µm step taken with a Mitutoyo BD Plan APO 20X/0.42 ∞/0 mm microscope objective + Nikon 200 mm F4 AIS telephoto lens + Nikon D810 camera (magnification 20×; technique described here).