Cecidomyiidae

Macrodiplosis

Quercus falcata

Alabama

Arkansas

Delaware

Florida

Georgia

Illinois

Indiana

Kentucky

Louisiana

Maryland

Mississippi

Missouri

New Jersey

New York

North Carolina

Ohio

Oklahoma

Pennsylvania

South Carolina

Tennessee

Texas

Virginia

West Virginia

Quercus imbricaria

Iowa

Kansas

Massachusetts

Michigan

Quercus palustris

Connecticut

Maine

Nebraska

Rhode Island

Wisconsin

Ontario

Quercus rubra

Minnesota

New Hampshire

Vermont

New Brunswick

Nova Scotia

Prince Edward Island

Quebec

Quercus velutina

71st Report of the State Entomologist on injurious and other insects of the state of New York

Macrodiplosis q-rubra-early-vein-swelling

Cecidomyia sp.

Fusiform, thin-walled, striate, pale green vein swelling, length 5 mm, diameter 3 mm, on red oak

Cecidomyia sp.

Subglobose or fusiform, pale green, yellow margined leaf fold, mostly on under surface, length 1/8 to 1/4 inch, diameter 1/8 inch, gall midge.

Plant Galls and Gall Makers

A small elongated succulent swelling on the lower veins of Quercus rubra in early spring as leaves are emerging from the buds. They are typically found toward the edge of the leaf, often near the end of a lobe and with an elongated "pin" extending the vein. The walls are somewhat thick and succulent but open onto a large hollow space containing white larvae resembling those of the genus Macrodiplosis. The galls are of a similar shape to those of Macrodiplosis niveipila but lack pubescence (though some hairs can be present from the host leaf, the surface is not obscured). They apparently occur at an earlier phase of leaf development than Macrodiplosis majalis, which is similar but always found to one side of the vein or the other, leaning supine against the leaf and leaving the vein unmoved. The present gall is generally symmetrical around the vein, swelling perpendicular to the leaf and directly displacing the vein. They seem to deform more rapidly and severely than those of M majalis as well. 

Fresh galls have been observed in April in [Virginia](https://www.inaturalist.org/observations/75373888) [(2)](https://www.inaturalist.org/observations/75268831), in May in [Texas](https://www.inaturalist.org/observations/77494825), [Michigan](https://www.inaturalist.org/observations/78784742) [(2)](https://www.inaturalist.org/observations/78301720) [(3)](https://www.inaturalist.org/observations/78301721) [(4)](https://www.inaturalist.org/observations/78301719), [Ontario](https://www.inaturalist.org/observations/13010873), [Maine](https://www.inaturalist.org/observations/79631945), [Ohio](https://www.inaturalist.org/observations/78247073) [(2)](https://www.inaturalist.org/observations/77980513) [(3)](https://www.inaturalist.org/observations/77931863) [(4)](https://www.inaturalist.org/observations/77923962), [New York](https://www.inaturalist.org/observations/77843364), [New Jersey](https://www.inaturalist.org/observations/77815356)

Old galls have been observed in May in [New Jersey](https://www.inaturalist.org/observations/79339083), [Ohio](https://www.inaturalist.org/observations/79075452) [(2)](https://www.inaturalist.org/observations/77818151), June in [Ohio](https://www.inaturalist.org/observations/48945151), November in [Ohio](https://www.inaturalist.org/observations/64883689) [(2)](https://www.inaturalist.org/observations/64634186)  and [Connecticut](https://www.inaturalist.org/observations/64306152)

A similar gall was observed on Quercus imbricaria in May in [Ohio](https://www.inaturalist.org/observations/78367641) and on Quercus palustris in May in [Ohio](https://www.inaturalist.org/observations/77964232) and [New York](https://www.inaturalist.org/observations/78177839). Quercus velutina in Michigain in [May](https://www.inaturalist.org/observations/47123195). Quercus falcata in North Carolina in [April.](https://www.inaturalist.org/observations/111880376)

Gallformers ID Notes