Nearly all ctenopelmatines are parasitoids of sawflies, and not surprisingly most of the records are from Tenthredinidae, the largest family of sawflies. Based on available records, there are also various genera that have specialized, respectively, on argids, cimbicids, pamphiliids, and pergids. A few of the ctenopelmatine genera are well-documented as parasitoids of immature Lepidoptera. Ctenopelmatines oviposit in eggs or various larval instars and emerge from host cocoons.
Most specialists recognize at least 6 tribes: Ctenopelmatini, Euryproctini, Mesoleiini, Perilissini, Pionini, and Scolobatini. We recognize Westwoodiini as a tribe separate from the Scolobatini, and the Seleucini is also recognized as a separate tribe and placed in the Ctenopelmatinae by some authors. Tribal classification is in need of revision, as the monophyly of most tribes is not well established.