In the past three years of the Cascades Butterfly Project, the Chryxus Arctic (Oeneis chryxus) has been a rare sight. So, the Cascades Butterfly Crew experienced quite a thrill on July 17 when we caught the first Chryxus Arctic identified on Easy Pass since the start of the project. The majority of sightings of this species are in the Rockies with an occasional sighting in the Washington Cascades.
The Chryxus Arctic is an especially exciting because of its short flight period. These butterflies peak in flight during early summer, typically June to July, which limits the amount of time researchers are able to document them.
This contrasts sharply with the amount of time it takes a caterpillar to mature to an adult; two years! This species hibernates as young caterpillars the first winter and then again as mature caterpillars the second winter. What a resilient species!
Our crew was able to confirm it as a Chryxus Arctic by inspecting the dorsal forewings for a post median line that forms a birds head with a bill pointing out between the first and second "eyespots" (dorsal side).
Bird's-head pattern on the dorsal forewings of the Chryxus Arctic. Photo: NPS/James Heintz
And the ventral view (no bird's-head visible!). Photo: NPS/James Heintz
We are extremely excited about this find and will continue to keep you updated on additional discoveries and sightings.
Always watching those butterflies flutter-by,
The Leaping Lepidopterists