Arrowhead Blue Butterflies
Arrowhead blue butterfly caterpillars are adapted to rely on lupines and milk vetches as their host plant, for food, while adult butterflies live on nectar from various flowers including mustards and thistles.
Arrowhead blues or Glaucopsyche piasus have a wingspan of 1-1/8 to 1-3/8 inch. Their upper wing surface on males is violet blue-- duller on females-- with a dashed white fringe. The underside is gray with black dots and a light row of "arrowheads" points inward on the hindwing, giving the arrowhead blue butterfly its name.
Arrowhead Blue Butterfly
Arrowhead Blue Butterfly on a mustard flower
Arrowhead Blue Butterflies mating
