Bug FAQSpeckled Gall Wasp
Besbicus mirabilis
The speckled gall wasp makes galls on oak trees in North America. It lays eggs on the underside midrib of Oregon oak leaves and its second generation creates bud galls. It is found along the Pacific coast from British Columbia to northern California and was formerly called Cynips mirabilis.
Source: Wikipedia
How to recognize it
It is also known as the speckled gall wasp.
Source: Wikipedia
What it eats
The female oviposits on the midrib of the underside of Oregon oak leaves.
Source: Wikipedia
Life cycle
The second generation induces bud galls.
Source: Wikipedia
Lookalikes
It was formerly classified as Cynips mirabilis.
Source: Wikipedia
Where it is found in the US
Recorded in 3 of 51 states and DC. Most records: Oregon, Washington, California.
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
Questions people ask
What other scientific name has this wasp been known by?
It was formerly called Cynips mirabilis.
Source: Wikipedia
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Besbicus_mirabilis
Look it up elsewhere: iNaturalist · BugGuide · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-24.