Grape Seed Chalcid, Evoxysoma vitis (Saunders) (Hymenoptera: Eurytomidae)
The grape seed cha1cid is a small, wasp-like insect that lays its eggs in grape berries when the berries are nearly full size but still green. Larvae hatch, enter the seeds and feed on the contents of the seeds. The fruit around the infested berries shrivels and dries out. The grape seed chalcid overwinters within grape seeds on the ground. Adults emerge in late May or June.
Outbreaks of this insect are rare. Grape cultivars having smaller berries appear to be preferred over those which bear larger fruits. The grape seed chalcid attacks generally are confined to wild grapes.
Current pesticide recommendations may be found HERE