Dasineura folliculi Felt is reported from Solidago rugosa Miller and S. gigantea Aiton ... The galls are usually 4-8 cm in length and 1-3 cm in width, although larger galls of up to 6 cm in width were sometimes observed, especially on S. gigantea. Galls are induced in apical buds. Leaves composing the gall become widened and thickened at the base, are tightly wrapped together when the larvae are young, and loosen as the gall and the larvae age. Larvae feed gregariously among the gall leaves. ... The central leaves of old galls that no longer contained larvae were often brown and dead, although the shoot usually continued to grow normally after the larvae had left, leaving a slightly thickened region on the stem and shorter internode distances ... Galls are usually characterized by yellowish-green spots on the leaves composing the gall and on some leaves below it. These spots, which are probably caused by larval feeding, do not occur in bud galls of Rhopalomyia capitata Felt that occupy the same niche on S. gigantea .... galls tend to become spottier as they mature.
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The description of the gall given by Felt (1909, 1915) for D. radifolii no doubt refers to galls of the last generation in the fall, because it is indicated that the galls were only 1 cm in length and that adults were reared in mid-April. This is in accordance with our findings that galls of the last generation are often considerably smaller than those of previous generations. The adults reared by Felt thus probably represented the first generation of adults that emerge from the soil after the winter diapause.
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Here we .... present behavioural, morphological, ecological and genetic evidence for the occurrence of HAD [Host-Associated Differentiation] in the gall midge Dasineura folliculi (Diptera: Cecidomyiidae) on two sympatric species of goldenrods (Solidago rugosa and S. gigantea).

Larvae in leafy apical bud gall on Solidago rugosa...

Bud or flower gall...
Galls made up of bud leaves, often as rosette on foreshortened stem...
Closed cluster of several leaves on apex of branch...Dasineura radifolii Felt

Larvae are gregarious among the leaves forming the cluster, which is about 1 cm long. The original series was found among leaves near the base of the plant. This or possibly another Dasineura occurs on apical galls on S. canadensis and relatives...