Cupido amyntula    

common name     Western Tailed Blue

Widespread in many habitat types; fond of meadows, clearings roadsides and pastures.

Flies in a single yearly brood from May to August, most common in mid June to early July.

The pale, chalky undersides with tailed hindwings make this species very distinctive.

life history
Unknown for Alberta. Mature larvae are variable in colour, and range from yellow to green with a dark green or reddish dorsal stripe, pink lateral stripe, and red or pink oblique bands (Layberry et al. 1998). Larvae overwinter and are often tended by ants (Layberry et al. 1998). Guppy & Shepard (2001) provide a picture of the pupa, which is cream-coloured with a row of black dorsal and lateral spots, and a covering of fine hairs.

Not of concern.

diet info
The larvae are legume-feeders, although no hosts have been recorded for Alberta; elsewhere, they feed on pea-vine (Lathyrus sp.) (Layberry et al. 1998) and vetch (Vicia americana) (Guppy & Shepard 2001).

Although this species is widespread throughout western North America from Alaska to northern Mexico (Opler 1999), it is not strictly a western species as the name implies: it also occurs east to north-central Ontario, with an isolated population on the Gaspé Peninsula of Quebec (Layberry et al. 1998).

species page authorSchmidt, B. C. 

quick link


Logo Department of Museums and Collections ServicesLogo University of Alberta