Description
The Western Tailed-Blue (Cupido amyntula) is a small butterfly with light blue wings, bordered with black on the upper side and grayish undersides marked with small black spots and a thin tail, typically found in open woodlands, meadows, and prairies across western North America, as well as boreal areas of the north. I have yet to see this species in Minnesota so the images above are from Colorado.
Range
Very uncommon in the northeastern part of the state.
Similar Species
Western Tailed Blue is extremely similar to Eastern Tailed Blue but only found in the arrowhead of Minnesota. Westerns have less orange markings and the forewing shape is less rounded. No other blues in Minnesota have tails.
Host Plants
Here are the main larval host plants: Lupine (Lupinus spp.), Vetch (Vicia spp.), Wild Pea (Lathyrus spp.), Sweet Clover (Melilotus spp.), Astragalus (Astragalus spp.)
Flight
Unclear but May-June seems to be the flight period in Minnesota. May be double-brooded but that’s not yet clear.