Euura lemmoniae, n. sp.

[Photos of many examples of this gall appear in Figure 36, page 16 of the pdf]

GALL.—Lasiolepoid-type (Fig. 36); very similar to that of E. lasiolepis but usually smaller (10-60 mm X 6-15 mm) and more globose; surface usually striate, matte; color dark green to red-brown; willow a clustering shrub usually under 3 m tall, (rarely to 5 m) on boggy sites from upper yellow pine forest to upper lodgepole pine forest.

Host.—Salix lemmonii Bebb.

Range.—With the willow in the Sierra Nevada and adjacent ranges from Mount Lassen south, between 1500 and 2800 m, principally 2100-2500 m. The lower elevations are all in cold alpine meadows in the north-central Sierra Nevada, and equivalent to higher altitudes elsewhere.

Remarks.—Emergence and oviposition late April to mid June, peaking in late May; very abundant in alpine meadows, attaining enormous populations locally; see comment in discussion of speciation in stem-galling Euura.

Euura lemmoniae
Lemmon's stem-gall sawfly
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This sawfly induces abruptly swollen, potato-shaped, integral stem galls on Lemmon's willow (Salix lemmonii).