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I collected this beetle on South Crest Trl, 9400 ft, Sandia Crest 7.5’ quadrangle in the Sandia Mountains, Bernalillo Co, NM from a Berlese funnel loaded with soil from a 40 cm deep core sample taken of a formica argentea nest. That is, the beetle was from 0 to 40 cm deep in the nest. I posted a representative worker ant from the nest for identification purposes (linked below). It's unlikely the beetle was a regular resident of the nest. There were numerous gambel oaks (Quercus gambellii) nearby in an otherwise conifer forest.

From Mercado's interactive key(1), the beetle's 1.48 mm body length, straight anterior elytra margin, lack of pregular brush, and the antennae's 5 funcile segments and near cicular/oval club with 3 procurved sutures narrows the genus to Pseudopityophthorus or Pityophthorus. From Mercado's Pseudopityophthorus Fact Sheet, its well defined elytra stria and contiguous pronotal asperites imply it is Pityophthorus. I was unable to make much progress with the species key of Wood 1982(2). Expert confirmation of genus and ID of species is appreciated.

This image is from a CombineZP processed stack of 156 images with a 3.6 µm step taken with a Mitutoyo BD Plan APO 20×/0.42 ∞/0 mm microscope objective + Nikon 135 mm F2.8 AIS telephoto lens + Nikon D300 camera (magnification 13.5×; technique described here).

Worker from nest: