Janetiella brevicauda [Gagne lists Brachineura vitis, Dasineura vitis, Lasioptera vitis, and Rhizomyia vitis as likely inquilines in similar galls]

Vitis
Globular, irregular, usually red swellings on leaf, tendril, or flower
This is the most commonly reared species from these galls. It is probably multivoltine. Full-grown larvae cut a hole in the gall and drop to the soil to pupate. Galls sometimes cover so much surface that leaves and flower parts are deformed.

Range: New Hampshire to North Carolina, west to Ontario and Missouri

Lasioptera vitis OS

The grapevine tomato gall with its associate (Dasyneura vitis Felt) is probably more complained of than any other attacking the grape. The general appearance of these galls is shown in figures 32 and 33. The irregular, succulent galls occur on wild and cultivated grapes, often in a mass, suggesting at times a group of small tomatoes, and hence the common name. The galls may be on the leaves, leaf stalk, tendrils, or stalks of the fruit clusters. They vary in color from greenish yellow to reddish, the latter color being often the predominant one. When cut open several cells will be found and in each, at the proper time, an orange-yellow larva, the grub or maggot of the parent midge. When mature the grubs escape the galls through holes cut to the exterior, and fall to the ground where they change to pupae and remain until the following spring, the flies developing in time to start other galls on the tender growth.

No practical control for this insect is known. The cutting off and destroying of galls before the grubs have escaped should serve to reduce the attack another season.

Lasioptera vitis Osten Sacken

This gall consists of a bunch of swellings, very irregular as to size and shape, on new growth. Soft and juicy. Surface smooth, green with red tinge or all red. Polythalamous. May and early June. Common on wild grapes. Larvae enter ground to pupate. Fly late in June.

Lasioptera vitis

Large compound Gall on Grape-vine

The mass of irregular succulent swellings on the stem and leaf stalks of the grapevine (you do not mention the variety), each swelling about the size of a large pea and often having a rosy cheek, is produced by a pale reddish Gall-gnat, the Lasioptera vitis of Osten Sicken, At Figure 183, we represent the gall you sent, and at a section of one of the swellings, showing the cavities which contain the orange-yellow larva, which are the authors of the work. These larvae leave the galls and enter the earth to transform.

Lasioptera vitis [Gagne implies these are all most likely inquilines of Vitisiella brevicauda]

Irregular, tumid, lobulate, greenish or reddish leaf or tendril gall, diameter .5 to 1.5 cm.

Dasyneura vitis

Reared from similar gall.

Rhizomyia vitis

Reared from similar gall.

Brachyneura vitis

Reared from similar gall.

Janetiella brevicauda

Reared from similar gall.

MASSACHUSETTS
...
ex. Vitis (25+ adults)
...
These specimens were reared from succulent swellings in the tendrils and leaves of a cultivated grape (Vitaceae: Vitis sp.)
...
[confirms that this species is likely multivoltine based on rapid adult emergence in June and July from larvae collected only weeks earlier]

Lasioptera vitis OS

Swelling of the stem and leafstalks of the wild grape. This irregular succulent swelling, which becomes red on its stouter and riper portions, extends not only along the stem and leafstalks, but also invades the leaf-ribs. It contains round hollows of about 0.1 in diameter with an orange-yellow larva in each. Some of the hollows are often abandoned by their inmates and invaded by numerous Thrips. Having brought this gall home, I noticed that the larvae went under ground and obtained the fly on the 29th of June.

Janetiella brevicauda Felt
Lasioptera vitis OS
Dasyneura vitis Felt
Rhizomyia vitis Felt
Brachyneura vitis Felt
[Felt lists these as 5 distinct species inducing an identical gall but they are now considered likely either synonyms or inquilines of V brevicauda]

Vitis
Leaf or Tendril Galls
Irregular, green or reddish leaf or tendril gall, diameter 1/4 to 3/4 inches, midge, summer

Vitisiella brevicauda (Felt), new combination

[Cecidomyia] vitis tomatos Riley 1873. Invalid, a polynomial.
Janetiella brevicauda

This species is responsible for bright red, globular leaf and tendril galls of grapes in eastern North America (Gagne 1989) and probably beyond. Larvae collected in New Mexico agree with the description and are tentatively included under this species.

Range: MO, FL, MD, NM, NY, NC

One other described Nearctic cecidomyiid that forms galls on grape also has conspicuous sclerites on the female ninth segment but does not belong to Janetiella. This is Dasineura vitis Felt (1908: 341), a species that was originally and subsequently reared from leaf swellings purportedly similar to those made by V. brevicauda. Specimens of D. vitis in the Smithsonian Institution National Museum of Natural History (USNM) have been reared from blister leaf galls on grape as well, so this species may prove to be an inquiline. Dasineura vitis has toothed tarsal claws and also a broken costa at its juncture with R5. The general similarity between its ovipositor and that of Vitisiella is likely convergent, a case of different genera on a similar host sharing a similar striking character.

...from a globular leaf gall on Vitis sp.