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Species Plebejus acmon - Acmon Blue - Hodges#4380

Acmon blue for California in August - Plebejus acmon Acmon Blue Larva - Plebejus acmon Veined or Acmon Blue - Plebejus acmon - female Plebejus acmon - male Plebejus acmon - male Acmon Blue Butterfly - Plebejus acmon - male Plebejus acmon - male Acmon Blue? - Plebejus acmon - female
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Papilionoidea (Butterflies and Skippers)
Family Lycaenidae (Blues, Coppers, Hairstreaks, Harvesters)
Subfamily Polyommatinae (Blues)
Genus Plebejus
Species acmon (Acmon Blue - Hodges#4380)
Hodges Number
Explanation of Names
Acmon is the name of one of a pair of mischevious monkey-like characters (Cercopes, see also Wikipedia) in Greek/Roman mythology.
Male distinguished from the similar Lupine Blue (called Plebejus lupini by but Icaricia lupini by CBIF) by the paler blue upperside of wings, and the absence of a dark discal spot on the upperside of the hindwings.
Restricted mostly to California and Oregon, whereas the range of the similar Lupine Blue extends over most of western US and adjacent parts of Canada.
Internet References
pinned adult images plus info and US range map (
comparison images and range maps of Lupine Blue (; (CBIF)
Opler, Paul. A. 2003. FIXATION OF TYPE LOCALITY FOR LYCAENA ACMON WESTWOOD AND CHARACTERIZATION OF THE SPECIES AND ITS DISTRIBUTION. The Taxonomic Report of the International Lepidoptera Survey, Vol. 4, No.1. PDF format - Butterfly article which mentions this species as being one of the blues that ants help to pupate.