This European katydid was discovered near the Montreal airports in July, 1952, and from there spread into neighboring parts of Canada and the northeastern U.S. Then, in 2003, David Eades reported it to be well established in northeastern Illinois. For some years there were no records for the extensive area between New York and Illinois but recently the gap has been filled by records from Indiana and Ohio by Carl Strang, Philip Chaon, and Scott Namestnik. Furthermore, contributors to BugGuide have extended the range into Wisconsin and eastern Iowa. Details for the county records in the above map are in a SINA database. Wesley Teats recently (2013) reported the species from Rockingham County, Virginia.