Bug FAQYellow-margined Marsh Fly
Helophilus lapponicus · Order: Diptera · Family: Syrphidae
The Yellow-margined Marsh Fly is about 12.5 to 13.5 mm long (0.49 to 0.53 in). Adults have a deeply concave face with a large tubercle below the antennae and a black thorax marked with gray-white stripes.
Source: Wikipedia
Where it lives
Adults are commonly found on flowers, where they feed on nectar and pollen.
Source: Wikipedia
What it eats
Adults obtain energy from nectar and protein from pollen on flowers.
Source: Wikipedia
Where it comes from
It is a common species in northern North America, as well as northern Europe, Greenland and Siberia.
Source: Wikipedia
Where it is found in the US
Recorded in 4 of 51 states and DC. Most records: Alaska, Maine, Colorado, Wyoming.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in Canada. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What do Yellow-margined Marsh Flies eat?
Adults feed on flower nectar for energy and on pollen for protein.
Source: Wikipedia
Same family (Syrphidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Helophilus_lapponicus
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-28 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-28.