1.A small European sawfly (Cephus pygmaeus) whose larva does great injury to wheat by boring in the stalks.
2.Any of several small American sawflies of the genus Dolerus, as Dolerus sericeus and Dolerus arvensis, whose larvae injure the stems or heads of wheat.
3.Pachynematus extensicornis, whose larvae feed chiefly on the blades of wheat; called also grass sawfly.