Bug FAQQueen Alexandra’s Sulphur
Colias alexandra · Order: Lepidoptera · Family: Pieridae
Also called: Alexandra Sulphur, Queen Alexandra's Sulphur
The Queen Alexandra’s Sulphur butterfly has a wingspan of about 38 to 57 mm. Males look like the clouded sulphur but show a glossier yellow with an orange-yellow tint on the hindwing and a silvery grey underside with a median spot. It lives in western North America, from Alaska and the Northwest Territories down to Arizona and New Mexico.
Source: Wikipedia
How to recognize it
Males have a glossier yellow ground colour with an orange-yellow tinge, especially on the hindwing. The underside of both sexes is silvery grey on the hindwing with a silvery median spot.
Source: Wikipedia
Size
Wingspan ranges from 38 to 57 mm.
Source: Wikipedia
Where it lives
It is found in western North America.
Source: Wikipedia
What it eats
Larvae feed on species of Thermopsis, Astragalus, Lathyrus, Oxytropis, and Lupinus.
Source: Wikipedia
Life cycle
Adults fly from mid-May through August.
Source: Wikipedia
Where it comes from
Its range includes Alaska, the Northwest Territories, and extends south to Arizona and New Mexico.
Source: Wikipedia
Lookalikes
Males resemble the clouded sulphur (Colias philodice).
Source: Wikipedia
Where it is found in the US
Recorded in 17 of 51 states and DC. Most records: Colorado, Idaho, Oregon, Wyoming, Washington, New Mexico, Montana, Arizona.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in Canada; native in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
When can I see Queen Alexandra’s Sulphur butterflies?
Adults are on the wing from mid-May through August.
Source: Wikipedia
Where is this butterfly found?
It lives in western North America, from Alaska and the Northwest Territories down to Arizona and New Mexico.
Source: Wikipedia
How can I tell this butterfly apart from similar species?
Look for the glossy yellow with orange-yellow tinge on the hindwing and the silvery grey underside with a median spot.
Source: Wikipedia
Same family (Pieridae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Colias_alexandra
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.