Santa Barbara Field Guides – Butterflies|
Western Tailed Blue
wingspread .8-1.25 in.|
Recognition: Blue with white fringes; underside is white-gray with small black spots and orange spot near tail; tailed.
Flight period: Adults are active from May to October, and can be quite common in May and June.
Hostplants: The larvae eat the flowers of various Astragalus species (vetches and milkvetches, Fabaceae), and their pods.
Habitat: This Blue prefers open, shrubby habitats and moist lowlands.
Distribution: The Western Tailed Blue flies over the western portion of North America from northern Baja California to Alaska. The moist lowlands of southern California are especially popular and they have been recorded on the islands of San Miguel, Anacapa, and Santa Catalina.
Other: Caterpillars have been known to feed inside the pods of their hosplants. The ranges of this Blue and its similar species Everes comyntas overlap slightly, but the Eastern Tailed Blue is smaller and prefers dry, valley habitats.