I don't know who has the most "pursed lips"..Katrina Vanden Heuvel or Ceci Connolly, but they both look like they have never smiled in their lives..
No smile lines..but, those little lines that go straight up from the top lip from pursing in digust...LOL
Perfect description of those two prissymouths.
I think I know the look you are referring to -- it used to be called a simper, and CeCi Connelly had it down pat. I will miss her -- NOT!