Bug FAQFrosted Pyrausta
Pyrausta napaealis · Order: Lepidoptera · Family: Crambidae
The Frosted Pyrausta has a wingspan of about 17 to 22 mm. Adults are on the wing from March through August and again in October.
Source: Wikipedia
How to recognize it
The forewings are ash-gray along the inner and outer edges and dark brown along the leading edge and middle, while the hindwings are dark brown with a thin black line at the margin.
Source: Wikipedia
Size
Its wingspan ranges from 17 mm to 22 mm (0.67 to 0.87 in).
Source: Wikipedia
When you see it
Adults have been recorded flying between March and August and once more in October.
Source: Wikipedia
Where it comes from
Its native range includes the western United States and northern Mexico.
Source: Wikipedia
Where it is found in the US
Recorded in 4 of 51 states and DC. Most records: California, New Mexico, Arizona, Texas.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
When can I see Frosted Pyrausta moths?
Adults are active from March through August and again in October.
Source: Wikipedia
What do Frosted Pyrausta moths look like?
Their forewings are ash-gray on the edges and dark brown in the center, and the hindwings are dark brown with a thin black marginal line.
Source: Wikipedia
What family does the Frosted Pyrausta belong to?
It is a member of the moth family Crambidae.
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/Pyrausta_napaealis
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.