NU, your analysis is worthy of Sherlock Holmes!
Stepping out, here are more images...
A looser crop:
Full frame, Canon T1i with MP-E 65 at 4X:
The whole bug:
All images except the last are from the same stack -- MP-E 65 at 4X, f/4, focus step 0.037 mm, flash through a paper towel cylinder. The last one is a single frame at f/16 using Canon 100 mm macro lens, cloudy daylight.
Location is Stillwater, Minnesota.
Charles Krebs' guess was close enough that I had to hedge my response: "
but only roughly any of the wings mentioned so far".
It is certainly a true bug, not Pentatomidae but sometimes called a "stink bug" nonetheless. Ah, what a tangled web we weave...
Many thanks to everyone for contributing to this round of
What Is That Thing, Anyway?
--Rik