ID help needed on parasite.

I found this pupae of Episyrphus balteatus on one on the Teasels in my garden. I put it in a jar and to my surprise after about 4 weeks, this tiny little parasitic wasp  (please correct me if I am wrong) emerged from it. Can somebody help me with the identification of this parasite ? At which moment in its development was the host parasitised ?

Thanks a lot

Sylvie