This one was surprisingly straightforward to identify. The lack of a sclerite at the base of the lateral hump narrows the field quite a bit, and the other options followed fairly obvious characteristics to Clostoeca, which only has one species, Clostoeca disjuncta.
Described by Kondratieff, B.C. & Kirchner, R.F. (1984) New species of Taeniopteryx (Plecoptera: Taeniopterygidae) from South Carolina. Annals of the Entomological Society of America 77, 733–736.