The Old World tephritid Urophora quadrifasciata, a gall-inducing seed- head fly, was released in western and eastern North America for the biological control of knapweeds, Centaurea spp. (Asteraceae). Its establishment in the West (BC, CA, ID, MT, OR, WA) and in the East (CT, MA, MD, NH, NJ, NY, PA, RI, VA, VT, WV) has been previously reported. Collections from eastern Minnesota and western Michigan in 1995 are the first for the Northcentral region of North America.
Wheeler, A. G. Jr.
"Urophora Quadrifasciata (Diptera: Tephritidae), An Introduced Seedhead Fly New to Midwestern North America,"
The Great Lakes Entomologist, vol 28
Available at: https://scholar.valpo.edu/tgle/vol28/iss3/10