|scientific name Vanessa cardui (Linnaeus)|
common name Painted Lady
A migrant that can be found in almost any habitat in years that it is common.
Can be found throughout the season, from late April into October.
There are two other similar Vanessa; the first, V. virginiensis, occurs only very rarely as a migrant in Alberta, and the Painted Lady can immediately be distinguished from virginiensis by the row of three to four smaller eyespots on the hindwing underside; virginiensis has only two, much larger spots. Compared to the West Coast Lady (V. annabella), cardui has a large white spot two-thirds up the leading edge of the forewing, which is orange in annabella; cardui is also larger.
Royal Alberta Museum page
There are no named subspecies.
The light green cylindrical eggs have vertical ribs. Mature larvae are grey-brown with fine yellow and black markings and yellow branched spines (Guppy & Shepard 2001). Larvae live in silken leaf-nests on the hostplant (Layberry et al. 1998).
This species is rare or absent in Alberta in most years, but in years that populations build up in the southern United States, worn and often tattered migrants appear in May to lay their eggs, having flown thousands of miles. The offspring of these migrants emerge from July onwards. Since it is rare or absent in most years in Alberta, it is thought that Painted Ladies cannot overwinter here, and re-colonize in good migrant years. It is not known if summer brood individuals attempt a southward return migration in the fall here; they may in the southwestern US (Scott 1986), but there is no evidence they do so in British Columbia (Guppy & Shepard 2001).
Not of concern.
Many composites (Asteraceae) have been recorded as larval hosts, but thistles (Cirsium spp.) seem to be favoured in western Canada (Guppy & Shepard 2001).
This butterfly is more widespread tha nany other species in the world; although it does not tolerate hard winter forsts, migrants have been found on every continent save Antarctica; recorded as far north as northern Greenland (Scott 1986).
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