Callirhytis balanosa, new species

Host.--Quercus coccinea

Gall.--Found in spring on the immature acorns of the previous season, pushing out from within the cup and stunting the acorn. When growing in early spring they are fleshy, smooth, greenish, mottled with purple, flattened, and blunt at apex, where they secrete honeydew in such quantities that it often drips to the ground. They become full grown just as the buds are swelling. After they drop to ground in May the thin outer fleshy layer either shrinks up or decays away. The simple thin-walled larval cell inside is relatively large and transversely placed.

- LH Weld: (1922) Notes on American Gallflies of the Family Cynipidae Producing Galls on Acorns: With Descriptions of New Species^©

Reference: https://www.biodiversitylibrary.org/page/7305399#page/493/mode/1up