Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

  Sighting 1086469

Acmon Blue
Plebejus acmon

Observation date: June 23, 2016
Submitted by: RichHubie
Specimen type: Photograph
Observation notes: Last year I had some problems distinguishing between Acmon and Lupine Blues until late in the season. Let's see if I've learned anything since then. It would appear based on Opler, Kaufman and Glassberg that males of these two species can be separated based on a thin or broad dark FW edging, existence of a "black edging on inside of orange aurora", and having or not a "black discal dot on FW". So based on the thin dark edging, no black edging on the inside of the aurora and no discal spot that I can see, this is an Acmon Blue. Or maybe not!!
Status: Resident
Verified by: Ken Davenport
Verified date: June 28, 2016
Coordinator notes: To make things worse, there are several species within the Lupine Blue complex. And Glassberg admitted watchers can't tell them (acmon and lupini) apart, especially females.-Ken Davenport
Checklist region(s): United States, California, Mendocino County