Acmon Blue (Icaricia acmon) is in the Gossamer-winged Butterflies family (Lycaenidae). Across the U.S., iNaturalist users have logged 15,622 research-grade observations of it in our sample, peaking in July.
Seasonal pattern in the national data: summer visitor / breeder. Counts also reflect when people are out photographing, so compare months within a state rather than across states.
When to photograph Acmon Blue: observations by month (U.S.)
About Acmon Blue
Plebejus acmon, the Acmon blue, is a North American butterfly. It ranges mainly in California but can be seen north to Oregon and south through Baja California. The tops of the wings are blue with dark edges in males and brown in females. Its underside is white with black spots for both sexes with a red-orange band on the hindwing. Adults feed on nectar while caterpillars can feed on buckwheats, lupines, trefoils, and milkvetches.From Wikipedia via iNaturalist — article, CC BY-SA.
Acmon Blue by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| California | 15,143 | July | Apr–Oct |
| Oregon | 296 | August | May–Oct |
| Washington | 145 | May | May–Sep |
| Idaho | 16 | June | May–Sep |
| Nevada | 13 | August | May–Aug |
| Arizona | 6 | September | Sep–Oct |
Main season = months with at least 30% of the state's peak-month count.
Related butterflies (Gossamer-winged Butterflies)
Gray Hairstreak
Eastern Tailed-Blue
Red-banded Hairstreak
Marine Blue
Ceraunus Blue
Summer Azure
Western Pygmy-Blue
Reakirt's Blue
Photography tips
- Butterflies are sluggish on cool mornings — the best time for close approaches.
- Keep the sensor parallel to the wings for edge-to-edge sharpness.
- Nectar plants in bloom are reliable places to wait.
FAQ
When is the best time to photograph Acmon Blue?
Nationally, July has the most observations, with the main season from April to October.
Where is Acmon Blue most often seen?
The most observations come from California, Oregon, Washington.