Habitat ²

Adults emerge from hibernating pupae as the snow melts in May, and breed in sunny, low elevation, rocky or gravelly areas that have the larval foodplant, rockcress. Adults usually die by mid-June. Conical, ribbed eggs are laid on rockcress owerbuds. The green caterpillars are easily found feeding on the developing fruit and leaves of rockcress. The caterpillars are similar to those of the very abundant Large Marble (Euchloe ausonides), which are also found on rockcress. The pupae are cryptic, and very difficult to find; they hibernate through the late summer, fall and winter until the adults emerge the next spring.

Distribution ²

Yukon: Carcross to Whitehorse east to the Atlin Road.
North America: Yukon south to California along the coast.
Global: North America.

Distinguishing Features ²

The upperside of the wings is white with a distinctive, prominent orange-and-black tip on each forewing (paler and smaller in females). The underside of the wings is white with green marbling on the hindwings.

Sources and Credits

1. (c) d_robichaud, some rights reserved (CC BY-NC-SA), https://www.flickr.com/photos/77552493@N02/17055048749/
2. (c) L.G. Johanson, some rights reserved (CC BY-SA)

More Info

• iNaturalist.ca taxon page
• Animal Diversity Web
• Biodiversity Heritage Library
• BOLD Systems BIN search
• BugGuide
• Butterflies and Moths of North America
• CalPhotos
• CUIC Insect Images
• Global Biodiversity Information Facility (GBIF)
• HOSTS - a Database of the World's Lepidopteran Hostplants
• Moth Photographers Group
• NatureServe Explorer 2.0
• Pacific Northwest Moths

Range Map

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