Western Tailed-Blue

Cupido amyntula

Appearance: Small fine tails. Above, males are purple-blue; females slate gray. Tail spots when present are not conspicuous. Below, black spots are either indistinct or missing and one indistinct orange tail spot. (Eastern Tailed-blue has 2 orange spots, one near the tail and black submarginal spots).

Size: Small; 7/8 to 1 3/16 inches

Habitat: Moist habitats from plains to sub-alpine

Season: May to June; 1 brood

Larval Foodplant: Legumes, especially vetches and locoweed

Did You Know…
Tails on this blue are an example of convergent evolution with hairstreaks (Pyle, 2002).

Species Gallery (click to enlarge)