Rocky Mountain Dotted Blue

Euphilotes ancilla

Appearance: Hindwing beneath with a row of orange crescents edged outwardly with disconnected black spots that form a band. The underside of the forewings show numerous fairly bold black spots. Upper surface of male is blue with wide black borders; female is brown with orange on hindwing.

Size: Small; 5/8 to 1 inch

Habitat: Trails, rocky hilltops, ridges and slopes with host plant colonies

Season: Late April to early August depending on location and elevation

Larval Foodplant: Various Buckwheat (Eriogonum) species, especially Sulphur flower

Did You Know…
A member of the “Buckwheat Blues” and the genus Euphilotes, these are probably part of a complex similar to the Square-Spotted Blue complex and difficult to identify to species. “They are best identified by flight period, locality and association with type of buckwheat…” (Brock and Kaufman, 2003). Larvae overwinter and are tended by ants.

Species Gallery (click to enlarge)