Bug FAQEudonia spenceri
Eudonia spenceri · Order: Lepidoptera · Family: Crambidae
The forewings measure about 8 to 9 mm in length. It occurs in North America, from California and Arizona up to Montana and British Columbia. Adults are on the wing from April through September.
Source: Wikipedia
Size
The forewings are 8 to 9 mm long.
Source: Wikipedia
When you see it
Adults have been observed flying between April and September.
Source: Wikipedia
Where it is found in the US
Recorded in 9 of 51 states and DC. Most records: California, Alaska, Washington, Oregon, Idaho, Montana, Arizona, Utah.
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 are adult Eudonia spenceri active?
Adults are on the wing from April through September.
Source: Wikipedia
Where can I find Eudonia spenceri?
They are recorded from California and Arizona up to Montana and British Columbia in North America.
Source: Wikipedia
Same family (Crambidae)
Box Tree MothCydalima perspectalisDamages trees, gardens or crops
Celery Leaftier MothUdea rubigalis
Elegant Grass-veneerMicrocrambus elegans
Hawaiian Beet Webworm MothSpoladea recurvalisDamages trees, gardens or crops
Garden Grass-veneerChrysoteuchia culmellaDamages trees, gardens or crops
Bluegrass Webworm MothParapediasia teterrellusDamages trees, gardens or cropsSources
- Wikipedia: https://en.wikipedia.org/wiki/Eudonia_spenceri
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-27 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-27.