A male Canada Thistle Gall Fly in Harford Co., Maryland (5/17/2018). Photo by Josh Emm. (MBP list)
Canada Thistle Gall Fly gall in Anne Arundel Co., Maryland (6/16/2017). Photo by Bill Hubick. (MBP list)
A Canada Thistle Gall Fly gall in Baltimore City, Maryland (8/13/2016). Photo by Bill Hubick. (MBP list)
The gall of a Canada Thistle Gall Fly on Canada Thistle in Baltimore City, Maryland (6/18/2007). Determined by Boris Büche/BugGuide. Photo by Thomas Wilson. (MBP list)
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