Western Pygmy-blue (Brephidium exile) is the smallest butterfly in North America, with a wingspan of 0.5 to 0.75 inches. In our local area, it can be seen during all 12 months. However, there are only scattered sightings from December to March. Then numbers slowly increase to a slight peak in September. Host plants include White Goosefoot (Chenopodium album), various species of Saltbush (Atriplex), Sea Purslane (Sesuvium), and other plants in the Goosefoot family (Chenopodiaceae).

Despite the name, this butterfly is found as far east as Oklahoma and east Texas. Its preferred habitat is alkaline areas such as deserts, salt marshes, and wasteland, but it can also be seen in areas quite remote from any known host plants.

It is one of only 17 butterfly species found in Hawai’i.