Mitoura rosneri, the Rosner's hairstreak, is a butterfly of the family Lycaenidae.

It is found in western North America in British Columbia.

Subspecies C. r. plicataria is known as Barry's hairstreak.

[1] The larvae of subspecies M. r. rosneri feed on western red cedar (Thuja plicata),[1] while the larvae of subspecies M. r. plicataria feed on Rocky Mountain juniper (Juniperus scopulorum).

Both M. r. rosneri and M. r. plicataria are often treated as subspecies of Callophrys gryneus.