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For Insects, Spiders & Their Kin
For the United States & Canada

Species Rhopalomyia solidaginis - Goldenrod Bunch Gall

Adult fly emerging from pupal case - Rhopalomyia solidaginis - male Adult fly emerging from pupal case - Rhopalomyia solidaginis Adult fly emerging from pupal case - Rhopalomyia solidaginis - male Adult fly emerging from pupal case - Rhopalomyia solidaginis - male Adult fly emerging from pupal case - Rhopalomyia solidaginis Another bunch gall fly - Rhopalomyia solidaginis - female Goldenrod rosette/bunch gall, top  - Rhopalomyia solidaginis Goldenrod stem with multiple rosette galls - Rhopalomyia solidaginis
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon ("Nematocera" (Non-Brachycera))
Infraorder Bibionomorpha (Gnats, Gall Midges, and March Flies)
Superfamily Sciaroidea (Fungus Gnats and Gall Midges)
Family Cecidomyiidae (Gall Midges and Wood Midges)
Subfamily Cecidomyiinae (Gall Midges)
Supertribe Lasiopteridi
Tribe Oligotrophini
Genus Rhopalomyia
Species solidaginis (Goldenrod Bunch Gall)
Explanation of Names
Author: Loew, 1862
Identification
Eastman (1) states some other flies do make similar galls.
Gall is relatively distinctive--see photo.
Remarks
The female deposits an egg at the tip of the growing plant. Its larva secretes a chemical that prevents the goldenrod stem from growing although it continues to produce leaves, thus a shortened bunch of leaves is formed.
Print References
Arnett, p. 859, describes briefly (2)
Eastman, p. 154, illustrates gall. (1)