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.
This is one of the most common Rhyacophila species in the East and Midwest, and it was reported by the Leonards as the most common in the Lower Peninsula of Michigan.
In 14 records from GBIF, adults of this species have been collected during May (57%) and June (43%).