Callophrys xami, commonly referred to as the xami hairstreak or green hairstreak, is a butterfly included in the subgenus Xamia and the genus Callophrys in the family Lycaenidae. It was described by Tryon Reakirt in 1867. Other common names for this species, depending on the region, include green hairstreak and elfin. C. xami is considered to be a very rare species of butterfly, and its typical range is in southern Arizona and Texas including down south to Guatemala. The juniper hairstreak and the silver-banded hairstreak butterflies are similar species, but both differ significantly from C. xami in regards to the postmedian white line running across the butterfly wings.

The genus Callophrys consists of butterflies in the family Lycaenidae. It is apparently not monophyletic, but which of the taxa currently considered junior synonyms of Callophrys are valid genera remains to be determined.