Bug FAQBrother Moth
Raphia frater · Order: Lepidoptera · Family: Noctuidae
Also called: Yellowmarked Caterpillar
Source: Wikipedia
Brother moths have a wingspan of about 38 to 44 mm and belong to the Noctuidae family. They live across Canada from Nova Scotia to British Columbia and down to Mississippi, with adults flying from April or May through August. The caterpillars eat the leaves of several tree species, which can harm those trees.
Source: Wikipedia
How to recognize it
Brother moth (Raphia frater) is a member of the Noctuidae family.
Source: Wikipedia
Size
Its wingspan ranges from 38 to 44 mm.
Source: Wikipedia
What it eats
The larvae mainly eat aspen but also feed on alder, birch, cottonwood and willow.
Source: Wikipedia
Life cycle
Adults are on the wing from April or May to August, producing one or two generations each year.
Source: Wikipedia
When you see it
Adults can be seen flying between April and August.
Source: Wikipedia
Where it comes from
Its range covers the same area: Nova Scotia to British Columbia and down to Mississippi.
Source: Wikipedia
Lookalikes
In the western part of its range it can be confused with several close relatives.
Source: Wikipedia
Where it is found in the US
Recorded in 48 of 51 states and DC. Most records: Texas, Colorado, Michigan, Vermont, Oklahoma, Massachusetts, Minnesota, New York.
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
Do brother moth larvae damage trees?
Yes, the caterpillars feed on the leaves of aspen, alder, birch, cottonwood and willow, which can harm those trees.
Source: Wikipedia
When can I see adult brother moths?
Adults are active from April or May through August.
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/Raphia_frater
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.