Dismorphia thermesia, the pretty mimic white, is a butterfly in the Pieridae family. It is found in Guyana, Brazil, Ecuador, Peru, and western Bolivia. The habitat consists of transitional rainforests and cloudforests. The wingspan is about 50–57 mm (2.0–2.2 in) Adult males have a prominent black bar on the upperside of the forewings, extending from the basal area to the end of the discal cell. Females lack this bar and have more rounded wings.