I was puzzled when this ichneumon appeared inside a bag containing a Horse-chestnut leaf. I was hoping for a Colastes braconius (parasitoid of Cameraria ohridella) but knew immediately that the wing venation here was too simple. I emailed the image to Andrew Polaszek who suggested that this was in fact an aphidiine braconid i.e. a primary parasitoid of aphids. This group has very reduced wing venation in general, with fusion of the "ground plan" cells. Bill Ely examined the specimen and identified it as one of the Pauesia genus, probably Pauesia infulata.