Glencarlyn, [Virginia], 21.viii.1929, emg., “8-9.29”, Rudbeckia gall, J.C. Bridwell (1♂, USNM),...
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While the host species is not mentioned on any of the specimen labels, the male collected by Plakidas was reared from Rudbeckia laciniata (Plakidas 1982). It is interesting that this Melanagromyza atypically induces a gall, as apparent from both Plakidas’ specimen and the reared specimen from Virginia.
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[note: In Plakidas' paper (1982), these flies are identified as Melanagromyza matricarioides, were reared from larvae found in "plant tissue adjacent to the gall cells" (vs. from the gall cells themselves), and were assumed to not be the gall-maker. Asphondylia helianthiglobulus was assumed to be the gall inducer based on gall morphology and host identity. Lonsdale (2021) re-examined one specimen from this 1982 collection and identified it as M. virginiensis. I disagree with Lonsdale that this and the Bridwell record are evidence that the agromyzid is itself inducing a gall; it seems likelier to me that it is an inquiline or merely develops from adjacent tissue.]

- Owen Lonsdale: (2021) Manual of North American Agromyzidae (Diptera, Schizophora), with revision of the fauna of the “Delmarva” states^©