Gnorimoschema octomaculella

(Chambers, 1875)

Rabbitbrush stem gall moth

A small described by Vactor Tousey Chambers in 1875. The are -formers on rabbitbrush (Acamptopappus sphaerocephalus). Known from California and Washington.

Gnorimoschema octomaculella by (c) Tim Messick, some rights reserved (CC BY), uploaded by Tim Messick. Used under a CC-BY license.

Gnorimoschema octomaculella by (c) Ken-ichi Ueda, some rights reserved (CC BY), uploaded by Ken-ichi Ueda. Used under a CC-BY license.

Pronunciation

How to pronounce Gnorimoschema octomaculella: /ɡnɒrɪmoʊˈskɛmə ɒktoʊˌmækjʊˈlɛlə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from similar Gnorimoschema by the specific arrangement of markings: the large rust-red discal spot before the middle that contacts the spot, combined with the rusty-red spot at the end of the disc and the paired dusting before the . The association with Acamptopappus sphaerocephalus provides additional diagnostic context.

Images

Appearance

with a spot on the margin near the base, a large rust-red spot on the disc before the middle touching a brown spot placed just before it, another rusty-red spot at the end of the disc, and dense small of dusting before both the costal and dorsal . pale grayish fuscus.

Habitat

Associated with rabbitbrush (Acamptopappus sphaerocephalus) in dry, open where this occurs.

Distribution

Recorded from California and Washington in western North America.

Diet

feed on Acamptopappus sphaerocephalus (rabbitbrush), inducing formation in stems.

Host Associations

Acamptopappus sphaerocephalus - larval ; -forming

Life Cycle

form stem on the . Specific details of and timing are not documented.

Behavior

are attracted to ultraviolet light. are -formers, inducing abnormal stem growth on the .

Ecological Role

As a -former, modifies tissue to create protected larval chambers. The galls may accumulate soil at higher concentrations than surrounding plant tissues, though this has been demonstrated for congeneric G. gallaesolidaginis rather than this specifically.

Human Relevance

No direct economic or medical significance documented. Contributes to of western North fauna.

Similar Taxa

Gnorimoschema gallaesolidaginisAlso a -forming Gnorimoschema , but associated with goldenrod (Solidago) rather than rabbitbrush, and produces elongate stem galls rather than the stem galls of G. octomaculella. pattern differs.
Other Gnorimoschema speciesMany congeneric share similar size and general appearance; reliable separation requires examination of spot pattern and association.

More Details

Taxonomic history

Originally described as Gelechia octomaculella by Chambers in 1875, later transferred to Gnorimoschema.

Gall formation

Like other members of the , induce formation on their . The specific of galls produced by this on Acamptopappus sphaerocephalus has not been described in detail in available literature.