Alabama Butterfly Atlas

Butterfly: Wing Span: ¾ - 1¼ inches (2.2 - 3.2 cm) UPPER SURFACE (dorsal)  Male iridescent silvery blue with narrow dark borders; female idarker blue with wide borders. UNDER SURFACE (ventral) Gray-brown; both wings with row of white-ringed, round black spots. White wing fringe.

ID Tip: Row of round, white-rimmed spots on ventral wings

Egg: Pale blue-green; disc shaped. Laid singly on buds or tender growth of host plant.

Caterpillar: Gray green with dark green dorsal stripe and white dashes. May be suffused with red. Reported to turn reddish prior to pupation.

Chrysalis:  Light brown with dark brown speckles. Bean shaped.  Probably attached to debris at the bottom of host plant. The overwintering stage.

Silvery Blues occur in small colonies in Alabama’s northeastern mountains, although historical records indicate they may once have occupied more southern areas. They are habitat specialists, and their only flight is synchronized with the springtime bloom of their favored host plant, Carolina Vetch. This small, delicate legume clamors sporadically in rocky woodlands. Silvery Blues nectar from its flowers and lay eggs on its buds. Caterpillars eat buds, flowers, and sometimes leaves. They are usually tended by ants, which are attracted to sugary secretions produced by special "honey" glands. 

At least two subspecies fly in the eastern United States.  In addition to Carolina Vetch, 'Northern' Silvery Blues have adapted to use Crown Vetch as host material. An introduced, invasive legume widely planted for erosion control, Crown Vetch covers pastures, abandoned fields, and roadsides. Northern Silvery Blues responded accordingly and increased their southern range at a rate of approximately six miles per year. Whether our Appalachian-based Silvery Blues adapt to Purple Crown Vetch use in uncertain, but currently they remain known from very localized populations. Even in host filled habitat, they are usually absent. The best way to look for Silvery Blues is to locate a healthy colony of Carolina Vetch in northern Alabama counties and hope that in when its flowers appear in early spring, these tiny blue butterflies visit them.

Distribution and Abundance

A dot on the county map indicates that there is at least one documented record of the species within that county. In some cases, a species may be common throughout the county, in others it may be found in only a specific habitat. The High Count information shows the highest numbers recorded for this species as well as when and where they occurred.

The sightings bar graphs depict the timing of flight(s) within each of three geographic regions. Place your cursor on a bar within the graph to see the number of individuals recorded during that period.

The abundance calendar displays the total number of individuals recorded within each week of the month. Both the graphs and the calendar are on based data collection that began in 2000.

The records analyzed here are only a beginning. As more data is collected, these maps and graphs will paint a more accurate picture of distribution and abundance in Alabama. Submit your sightings to

Sightings in the following counties: Clay, Cleburne, Jackson

  • Map Symbol for Recent Sightings Sightings in the past 5 years
  • Map Symbol for Semi-Recent Sightings Sightings in the past 5 - 10 years
  • Map Symbol for Old Sightings Sightings more than 10 years ago

High count(s):

  • 2 - Jackson - 4/24/2014
  • 1 - Cleburne - 4/20/2014
  • 1 - Clay - 3/29/2015
County Distribution Map

View county names by moving the mouse over a county or view a map with county names

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
3 1 1 2


Rich, moist deciduous woodlands, hardwood forest slopes and ravines, and rocky North Alabama woods.

Silvery Blue
Silvery Blue (Glaucopsyche lygdamus)
© Sara Bright
Carolina Vetch with Phlox

Host and Nectar Plants

Reports from nearby states list plants in the Pea family (Fabaceae), especially Carolina Vetch (Vicia caroliniana).

Carolina Vetch has not yet been documented in Alabama but is strongly suspected.

Silvery Blue
Silvery Blue (Glaucopsyche lygdamus)
© Sara Bright
Carolina Vetch
Silvery Blue
Silvery Blue (Glaucopsyche lygdamus)
© Matt Hunter
Carolina Vetch

Landscaping Ideas