Studies on Hymenopteran Parasitism of Drosophila
Flies of the genus Drosophila are subject to attack by anumber of parasitic forms. Sturtevant (1921) has listed recordsof parasitism by protozoa (Leptomonas), fungi (Muiaria andStigmatomyces), nematodes, mites and v~rious hymenoptera.According to Sturtevant, Perkins (1913) has bred at leastfive species of hymenoptera, belonging to the proctotrupoid,cynipoid and chalcidoid groups, upon Drosophiline flies.H.S. Smith has bred an unidentified proctotrupoid and achalcidoid, Pachy crepoideus dubius Ashmead* from bothDrosophila melanogaster ani D. hydei. Kieffer ( 1913) hasdescribed three species of hymenoptera from Africa collected by Silvestri and stated by him to be parasitic on Drosophila,species not given. They are Trichopria (Planopria) rhopalica(Diapriidae), Ashmeadopria drosophilae (Diapriidae), and theinsect which forms the subject matter of the present investigation,Eucoila drosophilae (Figitidae).
There are in addition a number of predacious enemiesamong wasps, spiders, flies and beetles.
The present account is concerned with parasitism of variousspecies of Drosophila by Eucoila drosophilae Kieff. The waspswere found b y Dr. w. P. Spencer who exposed traps in aneffort to collect Drosophila at Long Lake, Ohio, in Sept. 1934 .Drosophila larvae from the trap gave a large number of pupaefrom which wasps emerged in considerable proportions. Sincethat time stock s have been maintained in culture on Drosophilamelanogaster.
