I checked the B. lacunarium in my collection (I only have three) and they all do appear to have reduced wings. The transverse microsculpture is there also, but a little difficult to see with my setup (30x is the highest I've got).

But: I looked up lacunarium in Larochelle and Lariviere (2003), and under dispersal power they say, "Wing-dimorphic: brachypterous (mostly; incapable of flight) or macropterous (probably capable of flight)."
Their references for the species are Lindroth's manuscript, Erwin's Plummers Island paper, and Will et al's paper on Lake Erie carabids, none of which say anything about adults of the species ever having full wings, so it must be based on their personal observations.

I had overlooked that wonderful reference book in my home lab. There it always rests three feet from my head. I will now adjust my working taxonomic key to include yet another instance of wing dimorphism among the ground beetles. Published personal observations will eventually get most things right! Thanks for your swift detective work.

Hard to believe I was disappointed by it initially... it's just not the kind of book that reveals its value at first glance. But on a species-by-species basis, it's a great tool as well as a handy place to scribble in one's own personal observations.

Elytra being longer and more parallel-sided in texanum vs shorter and more oviform in lacunarium should be a good character, although it is somewhat relative. (Other proportional measurements may also be useful, but I have too few specimens to draw any conclusion.)

Also I'm curious if the size range given by Lindroth is reliable, particularly whether B. texanum reaches much below the 5.8 mm threshold.