Bug FAQLittle Lined Underwing
Catocala lineella · Order: Lepidoptera · Family: Erebidae
Also called: Little Lined Underwing Moth
The little lined underwing is a moth in the family Erebidae with a wingspan of about 35 to 40 mm. It lives across much of North America, from eastern Canada down to Florida and west to Texas and Ohio. Adults fly in midsummer, typically from July through August, and the caterpillars eat oak leaves.
Source: Wikipedia
How to recognize it
Catocala lineella is commonly called the little lined underwing or steely underwing.
Source: Wikipedia
Size
Its wingspan ranges from 35 to 40 mm.
Source: Wikipedia
What it eats
The larvae feed on the leaves of oak trees (Quercus species).
Source: Wikipedia
Life cycle
Adults are on the wing from July to August.
Source: Wikipedia
When you see it
The flight period for adults is July through August.
Source: Wikipedia
Where it comes from
The species is native to North America, including eastern Canada and the United States.
Source: Wikipedia
Lookalikes
It was once considered a subspecies or synonym of Catocala amica.
Source: Wikipedia
Where it is found in the US
Recorded in 36 of 51 states and DC. Most records: Massachusetts, Connecticut, Pennsylvania, Michigan, Texas, New York, Florida, Virginia.
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 adult little lined underwings?
Adults are active from July through August.
Source: Wikipedia
Where is this moth found?
It occurs across eastern Canada and the United States, from Ontario and Quebec down to Florida and west to Texas and Ohio.
Source: Wikipedia
Is the little lined underwing related to any other species?
It was long treated as a subspecies or synonym of Catocala amica.
Source: Wikipedia
Same family (Erebidae)
Spongy MothLymantria disparDamages trees, gardens or crops
Fall Webworm MothHyphantria cuneaDamages trees, gardens or crops
Brown-tail MothEuproctis chrysorrhoeaCan irritate skin
Isabella Tiger MothPyrrharctia isabella
Virginian Tiger MothSpilosoma virginicaCan irritate skin
Salt Marsh MothEstigmene acreaSources
- Wikipedia: https://en.wikipedia.org/wiki/Catocala_lineella
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.