... widespread in desert margin, inland foothill, and montane habitats, but [ ] not known in coastal habitats, where it is replaced by a sister species, G. ericameriae ...

[Gnorimoschema coquillettella causes] gall-like deformities of terminal foliage tips. These are small, ca. 1 cm, onion dome-shaped. hollow 'galls' that appear to consist of leaflets sealed together like the staves of a barrel ... The larva skeletonizes within this shelter, and drops to the ground for pupation, leaving thin, partially eaten leaflets, which wither and dry by midsummer.

[Fig. 100, pg. 45, is a black-and-white photo of the gall or pseudo-gall]