Dasineura folliculi

Dasineura carbonaria

*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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*D. carbonaria* was wrongly associated with leaf blister galls of *Asteromyia carbonifera* (Osten Sacken), a mistake that was later corrected in Felt (1915), where a good description of the gall was given under *D. flavicornis*. The galls are composed of two to four leaves that are entwined together and sometimes adhered to each other along their margins to form a loose, elongated structure, usually 3-8 cm in length, without defined chambers, and sticky on the inside. The yellow larvae feed gregariously in the gall and cause feeding spots that resemble those in *D. folliculi* galls. However, because Euthamia leaves are long and slender, the spots are usually more aggregated than on *D. folliculi* galls, giving the affected leaves a bumpy or wrinkly appearance. The leaves composing the gall are yellowish green to purplish red, and in the latter case the gall is very conspicuous.

Taxonomy, life history, and population sex ratios of North American Dasineura (Diptera: Cecidomyiidae) on goldenrods (Asteraceae)