A comparative study of the structures of phylogenetic importance of female genitalia of the Cynipoidea (Hymenoptera)

The structure of the female genitalia of the Cynipoidea is described, compared with that of other Hymenoptera and its method of operation discussed. The comparative morphology and the major evolutionary trends within the superfamily are discussed. Cynipoidea have two extraordinary modifications of the female genitalia; the ninth tergite is very long, narrow and centrally bisected so that it apparently forms an extra pair of ovipositor ‘sheaths’ and the ovipositor is so elongate in some families that, in order to accommodate it within the gaster, it forms a complete loop.