Bug FAQLesser Maple Spanworm Moth
Macaria pustularia · Order: Lepidoptera · Family: Geometridae
Also called: Lesser Maple Spanworm
Source: Wikipedia
Adults have a wingspan of about 18 to 27 mm and white wings marked with wavy orange-yellow lines, often thicker along the top edge of the forewing. They live in deciduous and mixed forests across North America, from Nova Scotia to Florida and west to the Dakotas and Saskatchewan.
Source: Wikipedia
How to recognize it
White wings show wavy orange-yellow lines on both fore- and hindwings. The lines are often thicker at the upper edge of the forewing.
Source: Wikipedia
Size
Wingspan ranges from 18 to 27 mm.
Source: Wikipedia
Where it lives
Most common in deciduous and mixed forests.
Source: Wikipedia
What it eats
Larvae feed on maple leaves, especially red maple (Acer rubrum). They may also eat sugar maple (Acer saccharum) and silver maple (Acer saccharinum).
Source: Wikipedia
Life cycle
There is one generation per year.
Source: Wikipedia
When you see it
Adults are on wing May-July in the south and June-August in the north.
Source: Wikipedia
Where it is found in the US
Recorded in 39 of 51 states and DC. Most records: New York, Massachusetts, Michigan, Ohio, Vermont, Pennsylvania, North Carolina, Connecticut.
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
Can they damage my garden or trees?
Their larvae feed on maple leaves and can harm maple trees in gardens and forests.
Source: Wikipedia
Same family (Geometridae)
Willow BeautyPeribatodes rhomboidaria
Pale BeautyCampaea perlataDamages trees, gardens or crops
Large Lace-border MothScopula limboundataDamages trees, gardens or crops
Riband WaveIdaea aversata
Yellow Shell MothCamptogramma bilineata
Large Maple Spanworm MothProchoerodes lineolaDamages trees, gardens or cropsSources
- Wikipedia: https://en.wikipedia.org/wiki/Speranza_pustularia
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.