Bug FAQSaucer Gall Wasp
Feron gigas · Order: Hymenoptera · Family: Cynipidae
The saucer gall wasp makes small galls about 3 to 4 mm wide on oak leaves. These galls can be red, pink, brown, or purple and have a raised bump in the center where the larva lives. The wasp attacks scrub oak, blue oak, and Engelmann oak leaves.
Source: Wikipedia
How to recognize it
Galls appear in shades of red, pink, brown, or purple. The larval chamber shows as a raised bump in the middle of the gall.
Source: Wikipedia
Size
Galls from the all-female generation are about 3 to 4 mm across.
Source: Wikipedia
What it eats
The wasp induces galls on oak leaves, effectively feeding on those leaves.
Source: Wikipedia
Life cycle
The all-female generation emerges in winter and creates the small galls described. The bisexual generation makes brown, cone-shaped galls.
Source: Wikipedia
When you see it
The all-female generation emerges in winter.
Source: Wikipedia
Where it is found in the US
Recorded in 48 of 51 states and DC. Most records: California, Texas, Virginia, Oregon, Florida, Massachusetts, Illinois, Ohio.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Same family (Cynipidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Feron_gigas
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.