Rhopalomyia floccosa

Galls induced by this species are white and woolly in texture, with individual galls measuring about 5 mm in diameter. Coalescing galls may extend 30–40 mm in length. The galls are monothalamous (single-chambered) bud galls on stems. These characteristics distinguish R. floccosa from other Rhopalomyia species that may induce different gall morphologies on Artemisia hosts.

Found in habitats where the host plant Artemisia californica occurs, including coastal sage scrub, chaparral, and dry slopes in California and Baja California.

Native to western North America, occurring in California and Baja California where its host plant Artemisia californica is present.

Larvae feed within the gall tissue induced on Artemisia californica. Adults do not feed; their mouthparts are reduced or non-functional, as is typical for Cecidomyiidae.

• Artemisia californica - obligate hostCalifornia sagebrush; sole known host plant for gall induction

Development occurs within the woolly stem galls on Artemisia californica. Specific details of egg, larval, and pupal stages within the gall are not documented in available sources. Adults emerge from galls to mate and oviposit on new host growth.

As a gall inducer, modifies host plant growth and architecture, potentially affecting plant resource allocation. Provides microhabitat for inquilines and parasitoids within galls, though specific associates are not documented in available sources.

No direct economic or medical significance. Of interest to entomologists and naturalists studying plant-insect interactions and gall morphology.

• Rhopalomyia spp.Other species in the genus induce galls on Artemisia hosts, but differ in gall morphology, position, or host specificity. R. floccosa is distinguished by its white, woolly, monothalamous stem galls on Artemisia californica specifically.

• gall midge
• herbivore
• specialist
• plant parasite

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon