Bug FAQGirlfriend and Little Lined Underwings
Catocala amica · Order: Lepidoptera · Family: Erebidae
Also called: Girlfriend Underwing, Girlfriend Underwing Moth
The Little Lined Underwing is a medium-sized moth with a 35 to 40 mm wingspan. Adults fly from June to September and are often drawn to night lights. Its caterpillars feed on oak leaves.
Source: Wikipedia
How to recognize it
Forewings have a cryptic pattern, while hindwings are yellow with a black border and a separate black spot near the edge.
Source: Wikipedia
Size
Wingspan ranges from 35 to 40 mm.
Source: Wikipedia
Where it lives
Adults are active from June through September and are attracted to ultraviolet light at night.
Source: Wikipedia
What it eats
Caterpillars feed on oak (Quercus) species.
Source: Wikipedia
When you see it
Flight season runs from early summer to early fall.
Source: Wikipedia
Where it comes from
It occurs in southern Canada and the United States east of the Rockies, extending west to Oklahoma and Arizona and north to Minnesota and Texas.
Source: Wikipedia
Lookalikes
Unlike many other underwings, its tibiae lack spines. It is the type species of the genus Corisce, once proposed as a separate genus.
Source: Wikipedia
Where it is found in the US
Recorded in 37 of 51 states and DC. Most records: Texas, Connecticut, Florida, Illinois, Massachusetts, Pennsylvania, Michigan, Missouri.
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 expect to see Little Lined Underwings?
Adults are active from June through September, varying with location.
Source: Wikipedia
Why are they attracted to my porch light?
They are drawn to ultraviolet light at night.
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_amica
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.