Those kinds of field guides often have errors when it comes to these more obscure species/genera sad to say... And I'm not positive the species in Evan's field guide even is ID'd correctly. See Bugguide for more accurately identified specimens of that species.Thanks for your post. I just looked at my beetle, and it does lack the femoral spines. I don't understand, using Evans "Beetles of Western North America"
except for the lack of spines, I see very little resemblance to the picture of Coelocnemis dilaticollis, the body is not smooth, as it is in my apparently misidentified
beetle. Maybe that's the variability described, my beetle is on the large side of his dilaticollis description. Perhaps I'll change substrate and see what
happens.