Neuroterus niger var. perminimus

Neuroterus perminimus

Cynipidae

Neuroterus

Quercus alba

Alabama

Arkansas

Connecticut

Delaware

Florida

Georgia

Illinois

Indiana

Iowa

Kansas

Kentucky

Louisiana

Maine

Maryland

Massachusetts

Michigan

Minnesota

Mississippi

Missouri

Nebraska

New Hampshire

New Jersey

New York

North Carolina

Ohio

Oklahoma

Pennsylvania

Rhode Island

South Carolina

Tennessee

Texas

Vermont

Virginia

West Virginia

Wisconsin

Ontario

Quebec

Quercus bicolor

Nova Scotia

Cynipid galls of the eastern United States

Neuroterus perminimus (agamic)

Neuroterus niger

Neuroterus nigrum Gillette
Neuroterus niger Dalla Torre and Kieffer
Neuroterus perminimus Bassett

Gall. In numbers imbedded in the soft parts of the leaf of burr oak (Quercus macrocarpa) and white oak (Quercus alba). Monothalamous. Rounded or blister-like bodies protruding on both sides of the leaf, but somewhat more distinctly on the upper side; on the under side it has a minute nipple. Diameter 1-1.75 mm.

Habitat: MI; OH; IO; IN; IL; NY; NJ; PA

I fail to find any differences between the flies and galls of N niger and N perminimus, and I consider them one and the same species. The galls of N niger occur on burr oak (Q macrocarpa) and those of N perminimus on white oak (Q alba). The species is double brooded, the first brood emerges early in spring from galls of the previous year's growth, and the second brood appears during the latter part of June and early in July from galls formed by the first brood in May and June. The galls of the latter reach maturity late in August and in September.

The North American Species of Neuroterus and their Galls

Neuroterus perminimus agamic

The species was described from the sexual generation emerging in late June or early July from oval parenchyma galls in the current season's leaves of Quercus alba. The galls the writer refers to this species differ only in being found in October and yielding adults, all agamic females, in the early spring. Galls collected at Evanston, IL., gave flies April 1-23, 1909, and in 1910 from April 4-20. Brodie collected galls in October and reared adults May 9, 1888. 

Field notes on gall-inhabiting cynipid wasps with descriptions of new species

Neuroterus perminimus

Cells separate, numerous, elliptical, 1-2 mm long, showing on both sides of the leaf but more distinct on upper. On Q alba in June [sexgen] and similar galls in the fall [agamic]. Flies emerge from the overwintering galls April 1-23.

Cynipid Galls of the Chicago Area

Neuroterus perminimus agamic

Quercus alba
Leaf galls, integral
Elliptical parenchyma thickenings 1 mm long, in numbers in fall, producing the agamic generation. 

Quercus bicolor
Leaf galls, integral
Elliptical parenchyma thickenings in numbers in fall, more prominent above.

[Photo caption]
266. On Q alba. Also on Q bicolor. The agamic females emerged the next spring Apr 4-20 (IL).

The validity of this species is unclear. It was synonymized with [Neuroterus niger](https://www.gallformers.org/gall/870) by Nicholls et al 2022, and while the other synonymies given for N niger in that paper were dubious based on clear contradictions in gall morphology of the agamic generation, it does seem likely that purported agamic galls of N perminimus were in fact misidentifications of N niger. 

Gallformers ID Notes