Bug FAQYellow-spotted Sapeater
Brachyopa vacua · Order: Diptera · Family: Syrphidae
Size
Adults measure about 7 to 10 mm in length, roughly 8 mm long and 3 mm wide.
Source: Wikipedia
Where it lives
Adults are commonly seen around and on flowers.
Source: Wikipedia
What it eats
Larvae feed on the juice of decaying fungi growing under dead bark of tulip trees.
Source: Wikipedia
Life cycle
The larvae are rat-tailed type, about 7 mm long, cylindrical and wedge-shaped in profile.
Source: Wikipedia
Where it is found in the US
Recorded in 23 of 51 states and DC. Most records: Georgia, Pennsylvania, Maryland, Illinois, Virginia, District of Columbia, Kansas, Massachusetts.
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 the larvae eat?
They feed on the juice of decaying fungi that grow under dead bark of tulip trees.
Source: Wikipedia
What is the size of an adult?
Adults are about 7 to 10 mm long, roughly 8 mm by 3 mm.
Source: Wikipedia
Same family (Syrphidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Brachyopa_vacua
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.