[3] Belonocnema fossoria was first named in 1921 by Lewis Hart Weld based on individuals reared from asexual leaf galls collected on Quercus geminata from Clearwater, Florida.

[4] This synonymy was reversed in 1979 by Barnard Burks in his work the Catalog of Hymenoptera in America north of Mexico.

[2] The asexual generation galls are smooth, unilocular balls that appear on the ventral side of leaves.

[2] Belonocnema fossoria is only known from Georgia and Florida, following the range of its host plant, Quercus geminata.

[2] The large tibial spur and short, stout legs are likely adaptations to reach rootlets by digging through the sandy soil that Q. geminata often grows in.