Species Andricus dimorphus - Clustered Midrib Gall Wasp

Cynips dimorphus Beutenmüller, 1913

Adleria dimorpha

Andricus dimorphus

Weld (1) reports that adults emerged from collected galls in the second, third, and fourth springs, in late March or early April.

Forms galls on leaves in the white oak group. "Galls in rounded masses, a few to 30 in each, closely packed, clustered on the under side of the midrib or petiole, one-celled, globose, pointed basally, greenish, tinged with pink when fresh, grayish when old, individual galls, diameter 1/10 to 1/8 inch, diameter of masses from 1/4 to 1/2 inch, on white, burr and chestnut oaks." (2) In addition to these hosts (Quercus alba, Q. macrocarpa, and Q. prinus), Weld (1) lists Q. prinoides (dwarf chinkapin oak), and notes that there is a similar gall on Q. laceyi.