Euura geyerianae, n. sp.

[Photos of many examples of this gall appear in Figure 32, page 15 of the pdf]

GALL. — Exiguoid-type (Fig. 32); thick walled, shape bulbous, surface smooth, glabrous, undulating; young galls very blue-white glaucous, mature glossy green to mottled red and brown, occasionally glaucous; size 7-15 mm long X 5-10 mm wide; exit hole made by larva before pupating; willow a clustering, glaucous-branched shrub usually under 4 m in wet sites from lodgepole pine forest (in California) down to juniper-pinyon sagebrush woodland (in Oregon).

Host.—Salix geyeriana Andersson.

Range.—Adults reared only from type-locality in southern Oregon. Rare galls seen at Hobart Mills, Nevada County, California (elev. 1797 m) along Prosser Creek east of the Sierra Nevada crest

Euura geyerianae
Geyer's stem-gall sawfly
[Page 214]

This sawfly induces bulbous, abruptly swollen, integral stem galls on Geyer's willow (Salix geyerianae).