Male (and subsequent female) Eastern Tailed Blue

Hairstreaks and Blues
Location:  Mayfield, KY
August 1, 2010 11:43 am
I have been photographing many butterflies this summer. I bought a book on butterflies and moths. The pictures in the book are all illistrations which makes some identifications difficult. I have pictures of both hairstreaks and I believe the Eastern Tailed-Blue. (also how do you tell the difference between the female eastern tailed-blue and the gray hairstreak?… my book shows them both marked almost exactly the same.) I am sending the photo I have of what I believe is the Eastern Tailed-Blue. I would like to tag my album accurately, so please correct me if I am wrong. I still have a couple butterflies unidentified. Maybe I can send them in for your help later.
Janet Fox

Male Eastern Tailed Blue

Hi Janet,
The proper identification of the Gossamer Winged Butterflies in the family Lycaenidae, including the Hairstreaks and Blues, can be a daunting task, but we agree that this is a male Eastern Tailed Blue,
Cupido comyntas.  According to BugGuide:  “male’s wings above iridescent pale blue with brownish-gray along outer margin; forewings with a short oblique black bar near middle; hindwings with a row of submarginal black spots and a small orange spot at the base of each projecting tail. Female’s wings larger with longer tails, gray above on body and wings, 2 or 3 small orange spots with black dots near margin of hindwings. Wings of both sexes below silvery gray with small dark spots and a few orange spots near margin of hindwings. That written description fits this image of a male Eastern Tailed Blue posted to BugGuide, but your specimen has two orange spots on the upper side of the lower wing near the tails.  It seems there is a degree or variability, since another image posted to BugGuide has two spots like your individual.  Your photograph has captured the butterfly in the process of puddling, taking fluids and minerals from a damp spot on the ground, and you can see the extended proboscis in your photograph.  For a good guide book with photographs is Jeffrey Glassberg’s Butterflies Through Binoculars series, broken up into two volumes for east and west.

August 3, 2010
Thanks for the fast response.  I have attached a pic of the other one. I am thinking it is the female eastern tailed-blue.  My book doesn’t show the gray hairstreak well, so I am not sure which one it is.
Thanks again for the help.
Janet Fox
Mayfield, KY

Female Eastern Tailed Blue

Hi again Janet,
We didn’t notice until today that you wrote back with a photo of a female Eastern Tailed Blue.  We are adding it to your original posting.

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