Bug FAQWatermilfoil Leafcutter Moth
Parapoynx allionealis · Order: Lepidoptera · Family: Crambidae
Also called: Watermilfoil Leafcutter, Bladderwort Casemaker
The watermilfoil leafcutter moth lives across many U.S. states and Canadian provinces in North America. Its larvae build portable cases from plant material and feed on a variety of aquatic plants such as watermilfoil and pondweed. Adults can be seen flying throughout the year in the southern part of its range.
Source: Wikipedia
Where it lives
It lives in North America. Larvae construct portable cases from plant material.
Source: Wikipedia
What it eats
Larvae feed on aquatic plants including waterlilies, pondweeds, watermilfoil, watercress, spikerush, bladderwort and floating fern.
Source: Wikipedia
Life cycle
The species was first described by Francis Walker in 1859.
Source: Wikipedia
When you see it
Adults have been recorded on wing throughout the year in the southern region.
Source: Wikipedia
Where it comes from
Native to North America.
Source: Wikipedia
Where it is found in the US
Recorded in 31 of 51 states and DC. Most records: Florida, Texas, Massachusetts, Louisiana, North Carolina, New Jersey, Mississippi, Alabama.
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
What plants do the larvae eat?
They feed on a range of aquatic plants such as waterlilies, pondweeds, watermilfoil, watercress, spikerush, bladderwort and floating fern.
Source: Wikipedia
When are adult moths active?
Adults can be seen flying all year in the southern part of their range.
Source: Wikipedia
Where is this moth found?
It occurs across many U.S. states and Canadian provinces in North America.
Source: Wikipedia
Same family (Crambidae)
Box Tree MothCydalima perspectalisDamages trees, gardens or crops
Celery Leaftier MothUdea rubigalisDamages trees, gardens or crops
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/Parapoynx_allionealis
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.