Redescriptions of some known species of Trichogramma (Hym., Trichogrammatidae), showing the importance of the male genitalia as a diagnostic character

Twelve Trichogramma spp. are redescribed. These are: T. australicum Girault, T. dendrolimi Matsumura, T. euproctidis (Girault), T. evanescens Westwood, T. fasciatum(Perkins), T. japonicum Ashmead, T. minutum Riley, T. perkinsi Girault, T. pretiosum Riley, T. retorridum (Girault), T. semblidis (Aurivillius) and T. semifumatum(Perkins). Differences in male genitalia are emphasised, being most stable and reliable, and pigmentation as well as wing and antennal trichiation are described, being characters of supplementary importance for species diagnosis. Host and distribution records are also given. In the male genitalia, the shape of the dorsal expansion of the gonobase differs considerably in some species and the position of the chelate structures with respect to the tips of the gonoforceps also varies; the median ventral projection is large in some species, reduced in some and almost absent in others. A comparative account of the most distinguishing characters of the different species is included and a key to 15 species is provided