Cecidomyia? racemicola

Rhopalomyia racemicola

Gall. Green, smooth, rounded, tapering to a point at the apex, giving it a bud-like appearance. Inside it is hollow and contains a single larva. Length about 3 mm and 2.5 mm in diameter.

Found singly, or in clusters, among the racemes of different kinds of goldenrod (Solidago canadensis [sense unknown], puberula, serotina [gigantea] and probably other species).

Habitat: NC, NY, DC

The galls may be found in September and are somewhat difficult to detect, owing to their resemblance to the buds of the goldenrod flowers. The larvae leave the gall in autumn and enter the ground to transform.

...Dr. Rodney Dodge showed me some typical racemicolous galls from Solidago stricta [now probably S. virgata] found near his residence in Bradenton, Florida. Orange-red larvae were crawling on the inside of the vial containing the galls, almost all of which had a tiny round hole in the side. This was uncommon behavior for a Rhopalomyia...upon closer inspection, the Florida larvae proved to belong to Schizomyia.

Modified floret...
Gall onion shaped, short-pointed at tip...Schizomyia racemicola (Osten Sacken)

Galls are green to red, smooth, thin-walled, and weakly ribbed. Larvae are orange, very active, and leave the gall to pupate in the soil. Probably only one generation occurs per year. Hosts: S. canadensis [in a broad sense, including at least S. altissima and S. gigantea], S. leavenworthii