The Appalachian Brown (Satyrodes appalachia) is often confused with the Eyed Brown (Satyrodes eurydice) and the Northern Pearly Eye (Enodia anthedon). 
In the Appalachian Brown, the dark line on the underside is gently curved, not zigzagged as in the wings of the Eyed Brown.
In the Northern Pearly-Eye, the wing margins are slightly scalloped, the bands through both wings are wider, the underwings have a more gray coloration and the second eyespot on the forewings is always much smaller (sometimes absent).
The Appalachian Brown generally prefers woodland edges while the Eyed Brown is usually found in open wet meadows.

White Mountains area, New Hampshire, USA, 4 August 2017