Bug FAQMottled Duskywing
Erynnis martialis · Order: Lepidoptera · Family: Hesperiidae
The mottled duskywing is a small butterfly with a wingspan of about 25 to 29 mm. It lives in the eastern United States, southern Ontario and southeastern Manitoba, preferring oak-savanna habitats that have been reduced by development and agriculture. Caterpillars feed on wild lilacs such as New Jersey tea and redroot, while adults sip nectar from a variety of flowers.
Source: Wikipedia
How to recognize it
Erynnis martialis, known as the mottled duskywing, belongs to the skipper family Hesperiidae.
Source: Wikipedia
Size
The wingspan ranges from 25 to 29 mm.
Source: Wikipedia
How to get rid of it
Spraying DDT and carbaryl to control gypsy moths also harms mottled duskywing populations.
Source: Wikipedia
Where it lives
Urban sprawl, farming and logging have destroyed many of these habitats.
Source: Wikipedia
What it eats
Adults feed on nectar from flowers such as Bush houstonia, gromwell and Verbena stricta.
Source: Wikipedia
Life cycle
Two generations occur each year, from mid-May to late August.
Source: Wikipedia
When you see it
Adults are on the wing from mid-May through late August, producing two broods.
Source: Wikipedia
Where it is found in the US
Recorded in 34 of 51 states and DC. Most records: Georgia, New York, Colorado, North Carolina, Ohio, Alabama, Nebraska, Illinois.
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 do mottled duskywing caterpillars eat?
The caterpillars feed on wild lilacs such as New Jersey tea and redroot.
Source: Wikipedia
When can I see adult mottled duskywings?
Adults appear from mid-May to late August, with two generations per year.
Source: Wikipedia
Why are mottled duskywings declining?
Loss of oak-savanna habitat from development, agriculture and logging, plus pesticide use, are major threats.
Source: Wikipedia
Same family (Hesperiidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Erynnis_martialis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-24.