Bug FAQBelonocnema fossoria
Belonocnema fossoria · Order: Hymenoptera · Family: Cynipidae
Belonocnema fossoria is a gall-wasp that makes smooth, single-chambered galls on the underside of leaves and irregular, multi-chambered galls on small rootlets of sand live oak (Quercus geminata). It occurs only in the United States, specifically Georgia and Florida, where its host oak grows. The species has both asexual and sexual generations, with the sexual adults emerging from early March to mid-April as the oak leafs flush.
Source: Wikipedia
How to recognize it
Young leaf galls start orange or light brown and turn darker as they age.
Source: Wikipedia
Where it lives
Sexual galls are irregular, multi-chambered clusters that grow on small rootlets.
Source: Wikipedia
What it eats
The wasp forms galls on the oak species Quercus geminata.
Source: Wikipedia
Life cycle
Both asexual and sexual generations occur in its life cycle.
Source: Wikipedia
When you see it
Sexual adults emerge from early March to mid-April, matching the leaf flush of their host oak.
Source: Wikipedia
Where it comes from
It is known only from Georgia and Florida in the United States.
Source: Wikipedia
Lookalikes
It can be told apart from other Belonocnema species by a fore-tibia spur that is longer than the basitarsus and tibial spurs.
Source: Wikipedia
Where it is found in the US
Recorded in 4 of 51 states and DC. Most records: Florida, Alabama, Georgia, Illinois.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
When do the adult wasps appear?
The sexual generation emerges from early March to mid-April, coinciding with the leaf flush of Quercus geminata.
Source: Wikipedia
How can I tell this gall wasp apart from other gall wasps?
Look for a fore-tibia spur that extends beyond the basitarsus and tibial spurs; this feature is unique to Belonocnema fossoria.
Source: Wikipedia
Same family (Cynipidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Belonocnema_fossoria
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-27 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-27.