Silver-banded Hairstreak (Chlorostrymon simaethis)

Compare to Telea Hairstreak , Xami Hairstreak

(at balloon vine flower) note gray eyes and wide silver band

NABA Int'l Butterfly Park, Mission, Hidalgo Co., TX
August 15, 2004 (G Quintanilla)

Santa Ana NWR, Alamo, Hidalgo Co., Tx
October 22, 2004 (B Bouton)

female
 

Santa Ana NWR, Hidalgo County, TX
December 19, 2002 (J Howland)