|scientific name Euxoa difformis |
Arid native grasslands and badlands.
In Alberta adults have been collected in late August and early September.
A medium-size (2.9-3.5 cm wingspan) pale to dark grey or grey-buff moth. Highly variable in shade and pattern. The head thorax and abdomen are grizzled dark grey, and with a narrow dark band across the prothoraic collar. No basal dash, and the area around and between the orbicular and reniform spots is not darker than the rest of the wing. The antemedian and postmedian lines are usually prominent, the former single and jagged, the later also single but drawn outward at each vein. There is also an indistinct median band running down from the reniform spot. The orbicular and reniform are incompletely outlined in black scales. The orbicular is rounded or oval and almost as large as the reniform, which is kidney-shaped and usually darker in the lower half. The terminal area of the wing including the fringe is the same shade as the forewing ground. The terminal line is a series of narrow, dark crescents or saggitate marks, separate in some and joined in others. The hind wings are dull white or pale grey-buff, with darker shading on the veins and along the outer margin. A discal mark and a narrow median line are visible in most specimens. Male antennae fairly strongly biserrate. Male genitalia characters include relatively short saccular extensions (as short as or shorter than the harpes), a very small nipple-like second basal diverticulum on the vesica and a strongly reflexed vesica. This drab moth may be remarkably variable in appearance, even in collections from a single site.
The immature stages are unknown. There is a single brood each year, with the adults flying in late summer and early fall. The adults are nocturnal and attracted to light.
A widespread but uncommon species; no concerns.
Central Saskatchewan west to southern British Columbia, south to western South Dakota, southern Colorado, Southern Arizona and northern Baja California, Mexico. It has been collected in southern Alberta north to Erskine and Calgary.
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