Disholcaspis quercusmamma (Walsh and Riley), 1869.

Cynips quercusmamma
Holcaspis mamma
Diplolepis quercus macrocarpae
Holcaspis duricoria
Holcaspis duricaria
Cynips macrocarpae
Andricus macrocarpae
Andricus quercus-macrocarpae
Disholcaspis quercus-mamma
Disholcaspis quercusmamma

Hosts: Quercus macroarpa, lyrata, bicolor

Galls are formed in buds of Q. macrocarpa, Q. bicolor, and Q. lyrata. Galls become conspicuous during leaf flush in early spring, with one or more galls forming in the center among flushing leaves, or outside the bud around the base of new leaves. Galls are 2.7–3.2 mm long, smooth-surfaced, and ovoid with a thin, fragile wall. When developing, they are pale, sometimes creamy with green or pink coloration near the tip. Galls usually fade to light brown or buff when mature, and either fall off or become obscured as the surrounding leaves and twigs develop. Emergence holes from galls are rough-edged and are produced at or just below the gall apex. Blackened galls have been observed with the cause for the color unknown.

Range: throughout eastern and central North America, from southern Manitoba, east through New Brunswick, throughout the eastern USA, and as far south as northern Florida and eastern Texas. However, the range of D. quercusmamma potentially extends anywhere that potential host trees have been transplanted outside their native ranges, if the insects were also translocated (e.g., Edmonton and Fort Collins).

- Crystal McEwen, Scott Digweed, James A. Nicholls, Whitney Cranshaw: (2014) Description and Biology of the Sexual Generation of Disholcaspis quercusmamma (Walsh and Riley) (Hymenoptera: Cynipidae), with Notes on Associated Parasitoids^©