Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

  Sighting 1213172

Rocky Mountain Dotted-Blue
Euphilotes ancilla

Observation date: June 30, 2019
Submitted by: edz111
Specimen type: Photograph
Observation notes: These small (2cm or so) butterflies congregate in large numbers (dozen or more) and flutter close to dirt or muddy ground. The photographs show them with wings open and closed. Weather was warm (~27C) and dry.
Status: Resident
Verified by: A_baldini
Verified date: July 03, 2019
Coordinator notes: These are Rocky Mountain Dotted-Blues, Euphilotes ancilla. The Boisduval's Blue and Blue Copper are both larger, entirely lacking orange coloration on the ventral side. They are abundant in most of Colorado's foothills and mountains in June - early July.
Checklist region(s): United States, Colorado, Boulder County