Cynipidae

Dryocosmus

Quercus coccinea

Alabama

Arkansas

Connecticut

Delaware

Georgia

Illinois

Indiana

Kentucky

Louisiana

Maine

Maryland

Massachusetts

Michigan

Mississippi

Missouri

New Hampshire

New Jersey

New York

North Carolina

Ohio

Pennsylvania

Rhode Island

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Vermont

Virginia

West Virginia

Wisconsin

Quercus nigra

Florida

Iowa

Kansas

Nebraska

Oklahoma

Texas

Quercus palustris

Ontario

Quercus phellos

Quercus velutina

Minnesota

Cynipid galls of the eastern United States

New American Cynipid Wasps From Galls

Dryocosmus albidus (agamic)

Undetermined species [tentatively associated with D albidus]

Similar [to Phylloteras rubinum], depressed, pure white, 4 mm in diameter on under side of leaf of Q coccinea in fall, dropping in October.

Cynipid Galls of the Chicago Area

Dryocosmus albidus, new species

Hosts.--Quercus coccinea, Q. velutina

Gall.--A depressed sphere, fleshy, bare, smooth, pure white or pinkish on one side, measuring up to 5 mm. in diameter by 3.8 mm high. On underside of leaf in October. Not common. Similar in external appearance to Biorhiza rubina Gillette on white oaks but with a different internal structure, the larval cell and nutritive layer being central instead of basal.

Dryocosmus albidus

Quercus coccinea, velutina
Leaf galls, detachable
Depressed sphere, white or rosy, fleshy up to 5.4 mm in dia, on under side, single, late fall.

[Photo caption]
242. On Q velutina. Also on Q coccinea. Galls drop before the leaves. Adults emerged Mar 23 the second spring and Mar 22 the third spring (DC). See Fig 312 for structure of gall.

312. A depressed white sphere, fleshy, bare, up to 5.4 mm in dia on under side of leaf of Q velutina in the late fall, similar in external appearance to the above [Phylloteras rubinum] but internal structure is different and on a different host. 

Similar galls have been observed on Quercus phellos in North Carolina in [July](https://www.inaturalist.org/observations/88902281), on Quercus nigra in [Georgia](https://www.inaturalist.org/observations/122533491) and [Mississippi](https://www.inaturalist.org/observations/121320567) in June, and on Quercus palustris in Virginia in [July](https://www.inaturalist.org/observations/89555041). These hosts are added tentatively based on these observations.

Weld describes this gall as being found only in "late fall," but observations that otherwise match have only been reported on iNaturalist between June and August. 

Gallformers ID Notes