Wild Indigo Duskywing (Erynnis baptisiae) (Forbes, 1936)

Diagnosis: Erynnis baptisiae is very similar to the Columbine Duskywing (E. lucilius), though considerably larger (wingspan: 29 to 34 mm). The forewings are dark basally and paler towards the tip, and usually there is a distinct orange-brown patch in the centre of the wing.

Range: Found throughout the eastern U.S., this duskywing occurs in Canada only in southwestern Ontario northeast to the Toronto area.

Similar Species: The Columbine Duskywing (E. lucilius) and the Persius Duskywing (E. persius).
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Early Stages: The larvae have not been described, although baptisiae has been reared on various herb and shrub Fabaceae; in Canada it has been found mainly on Wild Indigo (Baptisia tinctoria) but probably feeds on tick-trefoil (Desmodium spp.) at Point Pelee (Alan Wormington, pers. comm.).

Abundance: In Canada it can be quite common in its restricted habitat.

Flight Season: There are two (possibly three) generations in Canada between early June and early October.

Habits: In parts of the U.S. this species has apparently switched its larval food preference to Crown-vetch (Coronilla varia), and is expanding its range along highways where Crown-vetch is planted as a ground cover (Opler and Malikul, 1992). In Canada it remains restricted to the dry sandy habitat of Wild Indigo.

© 2002. This material is reproduced with permission from The Butterflies of Canada by Ross A. Layberry, Peter W. Hall, and J. Donald Lafontaine. University of Toronto Press; 1998. Specimen photos courtesy of John T. Fowler.