Lysandra hispana - Provence Chalkhill Blue

Polyommatus-hispana-provence-chalkhill-b | PTKbutterflies
Polyommatus-hispana-provence-chalkhill-b | PTKbutterflies
Polyommatus-hispana-provence-chalkhill-b | PTKbutterflies

The only way I can tell this from coridon is that all these butterfly photographs were taken in the right region, Southern France, at a time (May-June) before coridon , which is a relatively late emerger, was flying. They are very similar indeed.  

Polyommatus-hispana-provence-chalkhill-b | PTKbutterflies
Polyommatus-hispana-provence-chalkhill-b | PTKbutterflies
Polyommatus-hispana-provence-chalkhill-b | PTKbutterflies