Looking at some references, I noted that the antennae of
Neohermes are supposed to be different from
Chauliodes, as well as the wing venation. I went back to the original images and pulled out one where an antenna was in focus. Inset shows right antenna near maximum enlargement. I see hairs, as in the description below, though they don't seem to be in rings.
Megaloptera of Oklahoma says:
Neohermes concolor (Davis) Adult: Medium sized, 25-40 mm long; mottled gray-brown in color; antennae moniliform, each segment of the male antenna with a ring of erect hairs; collection dates from 11 June to 2 August.
Brainy Dictionary says... Moniliform: Joined or constricted, at regular intervals, so as to resemble a string of of beads; as, a moniliform root; a moniliform antenna.
These photos seem to match the description from
Megaloptera of Oklahoma and the term "moniliform" well. So I
think this is a
Neohermes. I'm satisfied enough now to move it to the guide. Posting it forced me to look at more references.