Interesting that the host records for this wasp suggest a preference for miners in monocots, both flies and moths. I wonder what the origin of the Fagus sylvatica record is, since all of the listed host insects are miners in grasses, sedges, or iris.

The species evidently adventive or purposely introduced in North America. UCD has only a record for Canada, but the University of Wisconsin lists a specimen in its collection.

I found the paper (added to the guide page) that first reports this species in the Nearctic. The specimens first recognized as this species were reared in 1980, but it's not clearly stated that those are the oldest known specimens--the authors subsequently examined specimens from all over northern North America. They refer to it as a Palearctic species in the abstract, but otherwise I didn't see any discussion of its having been introduced. Since Dr. Heydon is one of the authors, he might be able to comment on this.