Oak Hairstreak (Satyrium favonius)
Oak Hairstreak
Oak Hairstreak (or "Northern" Oak Hairstreak, also formerly called "Northern Hairstreak") 
(Satyrium favonius)

Fermilab, Kane County, Illinois 
July 11, 2008  

We are at the northern edge of the range of this species.  This individual was nectaring near the bigs woods western edge, where I often see Banded Hairstreaks.  A bit of the upper side of the opposite wing shows due to the wing being slightly curled, not having fully expanded. 

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