Bug FAQMariposa Forester
Alypia mariposa · Order: Lepidoptera · Family: Noctuidae
The Mariposa Forester moth lives in California’s Coast Ranges and Sierra foothills, from Kern and San Luis Obispo counties up to Placer County. Its caterpillars feed on the wildflowers Clarkia bottae and Clarkia unguiculata, and the adults are on the wing in April through June. It looks like the similar Alypia ridingsii but can be told apart because its white wing spots lack the black lines that ridingsii has.
Source: Wikipedia
How to recognize it
It resembles Alypia ridingsii but its white wing spots have no black lines.
Source: Wikipedia
Life cycle
Adults are active and fly in April, May, and June.
Source: Wikipedia
When you see it
The flight period for adults is April through June.
Source: Wikipedia
Where it comes from
Its native range is the same Coast Ranges and Sierra foothills area of California described above.
Source: Wikipedia
Where it is found in the US
Recorded in 1 of 51 states and DC. Most records: California.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: endemic in North America; endemic in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What plants do the caterpillars eat?
The larvae feed on Clarkia bottae and Clarkia unguiculata.
Source: Wikipedia
How can I tell this moth apart from similar species?
It lacks the black lines that run through the white wing spots of Alypia ridingsii.
Source: Wikipedia
Same family (Noctuidae)
Ipsilon Dart MothAgrotis ipsilonDamages trees, gardens or crops
Fall Armyworm MothSpodoptera frugiperdaDamages trees, gardens or crops
Army Cutworm MothEuxoa auxiliarisDamages trees, gardens or crops
Large Yellow UnderwingNoctua pronubaDamages trees, gardens or crops
Silver ΥAutographa gamma
American DaggerAcronicta americanaCan irritate skinSources
- Wikipedia: https://en.wikipedia.org/wiki/Alypia_mariposa
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-25 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-25.