Acmon/lupine blue butterfly nectaring on buckwheat
Acmon and lupine blue butterflies can be seen throughout the spring and summer months, having multiple broods through the season, and can be found across eastern Washington.
Both acmon and lupine blue butterflies are adapted to rely on various wild buckwheats as host plants for their caterpillars to feed on, and acmon caterpillars also eat lupines (oddly, lupine blues don't eat lupines though). Adult butterflies gather nectar from various flowers including western clematis, white forget-me-not, and host buckwheats.
Acmon-lupine blue identification
The easiest way to identify acmon-lupine blue butterflies is to look at the pictures and compare with similar butterflies. Acmon-lupine blues are small, having a wingspan of about an inch more or less, and the upper wing surface on males is powdery blue while females are brownish. Both males and females have an ornate orange and black-dot arc on their dorsal (upper) hindwing. The ventral hindwing (underside) also has the orange and black-dot arc, with blue scintillae (glittery scales) encircling the black dots. The ventral hindwing is otherwise bluish gray with black spots. Square-spotted blue and dotted blue butterflies look similar but lack the glitter and are smaller, while Melissa's blue butterflies have the glitter but also have an orange arc extending up the ventral forewing edge.
Male acmon/lupine blue butterfly
nectaring on parsnip-flower
buckwheat
Female acmon/lupine blue butterfly
perched on snow
buckwheat - August
Acmon/lupine blue butterfly
crawling deep into snow
buckwheat
Acmon/lupine blue butterfly
nectaring on white
forget-me-not - May
Acmon/lupine blue butterfly
Acmon-lupine blue butterfly
nectaring on snow
buckwheat
