Rhopalomyia pomum

Identification relies on the distinctive galls produced on host plants: spongy, irregular growths on leaves of Artemisia tridentata. Adult midges are small, delicate flies typical of the family Cecidomyiidae, with reduced wing venation and long, bead-like antennae. Specific morphological characters for distinguishing R. pomum from congeners require examination of male genitalia and antennal structure.

Associated with stands of Great Basin sagebrush (Artemisia tridentata), which grows in arid and semi-arid regions of western North America including sagebrush steppe, shrublands, and dry mountain slopes.

Western North America, corresponding to the range of its host plant Artemisia tridentata: primarily the Great Basin and adjacent regions of the United States including California, Nevada, Utah, Oregon, Idaho, Wyoming, and Colorado.

Larvae feed on plant tissue within the gall structure on Artemisia tridentata. Adult feeding habits are unknown.

• Artemisia tridentata - gall inducerforms leaf galls

Induces gall formation on host plant leaves through larval feeding activity. The spongy gall tissue provides shelter and nutrition for developing larvae.

As a gall inducer, modifies host plant tissue architecture, potentially affecting leaf function and plant resource allocation. Serves as a food source for parasitoids and other natural enemies that attack gall midge larvae.

• Rhopalomyia spp.Numerous congeners also form galls on Artemisia species; differentiation requires detailed morphological examination of adults and gall characteristics.
• Other Cecidomyiidae on ArtemisiaMultiple gall midge species utilize Artemisia as hosts; gall morphology and location (leaf vs. stem vs. bud) help distinguish species.

• gall midge
• leaf gall
• Artemisia
• sagebrush
• Great Basin

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life