Can. Ent. 121: 929-932 (1989) Cyrtogaster vulgaris Walker, a pupal parasite of the alfalfa blotch leafminer, Agromyza frontella (Rondani), acts as a secondary agent as well. The adults, which deposit their eggs within host puparia, apparently do not discriminate between healthy leafminers and those parasitized by Dacnusa dryas (Nixon). The egg and larval cephalic structures of C. vulgaris are described and illustrated and the final-instar larval skins of the two parasite species are compared.
ResumeCyrtogaster vulgaris Walker, parasite de la pupe de I'agromyze de la luzerne, Agromyza frontella (Rondani), se manifeste Bgalement comme agent secondaire. Les adultes, qui pondent leurs oeufs h l'interieur du puparium de l'hBte, ne semblent pas pouvoir distinguer les agromyzes sains de ceux parasites par Dacnusa dryas (Nixon). Les auteurs presentent une description et des figures de l'oeuf et des structures cephaliques larvaires de C. vulgaris, et comparent les cuticules du dernier stade larvaire des deux es@ces parasites.