Acmon and Lupine Blue butterflies belong to the same genus of Lycaenidae butterflies (Plebejus). Of the two species, Lupine Blues have the larger range, extending from the Pacific Coast through the Rocky Mountain states.
Both species, especially the females, look very similar, making identification in areas of their overlapping habitat problematic.
For convenience sake, Lupine Blue (Plebejus lupini) represents the title of this article. However, both butterflies overlap in the territory the picture was taken, so the possibility exists that the pictures show the Acmon rather than Lupine Blue.
Identifying either butterfly is a realtively straight forward task. The ring of orange and black marks around the border of the lower wings represents the basic field identification mark.The orange spots are larger than the comparable orange spots on species in the Euphilotes genus.
The top pictures shows a side view of the butterfly with prominant orange and black markings along the wing border.
The bottom picture shows a top view of the female with the orange and black markings also appearing on the border of the top of the wings.
Males have blue color wings on the top. The Acmon Blue article shows the distinguishing characteristics of male on the bottom side of the wings.
