Nematinae is a subfamily of sawflies belonging to the family Tenthredinidae. It contains over 1250 described species in ~40 genera. Members of this subfamily feed on a wide range of plants and employ a wide range of feeding habits, both internally and externally, on their host plants.

Tenthredinidae is the largest family of sawflies, with well over 7,500 species worldwide, divided into 430 genera. Larvae are herbivores and typically feed on the foliage of trees and shrubs, with occasional exceptions that are leaf miners, stem borers, or gall makers. The larvae of externally feeding species resemble small caterpillars. As with all hymenopterans, common sawflies undergo complete metamorphosis.