Frosted elfin

The Frosted elfin is present along most of the east coast, except for Maine (where it is presumed to have been extirpated), with isolated populations existing in southeastern Texas (and surrounding areas), Michigan, Indiana, and Wisconsin. New Jersey may be the stronghold for this species (Schweitzer 1994), with Assunpink Wildlife Management Area (WMA) and Belleplain State Forest having well-known colonies in the state (Gochfield and Burger 1997).

Dry clearings and open areas that are natural (e.g. savannas) or of human origin (e.g. power-line right of ways and roadsides). The presence of food plants (see Diet) is also of importance.

Lupine (Lupinus perennis) and indigo (Baptisia spp.) are the major food and host plants of this species. Larvae feed on the flowers of fruits of the host plants, and the adults are nectar feeders.

Frosted elfins produce a single brood each year. Adults fly from late May to mid-June in New Jersey. The larvae or caterpillars feed on the host plants and then move into the leaf litter a few weeks after the adults stop flying in mid-June, and the larvae develop into pupae (Schweitzer 1994). Individuals overwinter as pupae in the soil or in leaf litter bound together with silk fibers. (Scott 1986).

This species was listed as threatened in New Jersey in 2001. The Frosted elfin is often locally rare and occurs in small isolated populations. It is believed to be extirpated from portions of its historic range, including Maine, Ontario, and possibly Texas. It currently is not listed for federal protection, but its rarity throughout its range might justify a federal status of threatened or endangered in the near future.

In 2005, several habitat enhancement projects, one inside Millville Wildlife Management Area (WMA), established host plants (wild indigo) along utility right-of-ways. It is unclear whether the habitat enhancement projects have been successful or not.