Admetovis oxymorus Grote, 1873

93-2806

Identification

Adults

Admetovis oxymorus is the darker of two similar moderate to large noctuid species (FW length of A. oxymorus is 19 - 21 mm) with gray forewings with white and light tan fields on the distal forewing that fly in spring and early summer at dry low to middle elevations. The forewing ground color is mottled and powdery lead gray, including the terminal area. A small patch of tan scales is present at the anterior wing base, and a red-brown and tan line is located at the trailing margin from the base to the antemedial line. The subterminal area is white adjacent to the postmedial line blending to tan near the very irregular subterminal line. The median area lateral to the reniform is similar white, as is the filling of the reniform spot. The basal, antemedial, and postmedial line other than the portion opposite the reniform spot are dark gray, double, and filled with slightly lighter gray. These lines are relatively inconspicuous. The series of spots on the veins marks the position of the postmedial line across the pale portion near the reniform spot. The median line is absent. The subterminal line is white with a prominent preceding dark red-brown shade that gradually widens from the apex to the trailing margin. This line starts at the outer margin below the apex, forms a very strong W-mark to the outer margin on veins M3 and CuA1. The moderately large round orbicular spot is similar to the transverse lines. The reniform spot is dark gray and is filled with light white and a red-brown central crescent. The hindwing is grayish tan with dark gray veins, discal spot, terminal line, and submarginal shade. The head and central thorax are brown, while the tegulae are gray with brown medial edges. The male antenna is bead-like.

This species is only likely to be confused with Admetovis similaris. It has pure white hindwings unlike the light brown hindwings of A. oxymorus. The ground color of A. similaris is smoother gray and the pale patch on the distal forewing is lighter white and ochre rather than mostly tan as in A. oxymorus. Admetovis oxymorus flies slightly later in the season where these species occur together and is less likely than A. similaris to be found in open steppe habitats.

Habitat

This species is widely distributed throughout much of western North America in moist forest and riparian habitats with elderberries.  In the Pacific Northwest, it is most frequent in riparian zones along creeks and canyonlands at middle elevations east of the Cascades.  It is fairly frequently collected on middle elevation ridges in the Cascades, but is rare at low elevations west of the Cascades.

Distribution

Pacific Northwest

Admetovis oxymorus is found in dry habitats throughout our area south of southern British Columbia. It is common in the foothills surrounding the Columbia Basin, but is not found in the dry interior of this region.

Global

The range of A. oxymorus extends from the Pacific Northwest south to California, Arizona, Utah, and Colorado.

Life History

Larvae

This species is a foodplant specialist feeding on elderberries (Sambucus spp.) in the Caprifoliaceae.

Adults

This moth is single brooded and flies in late spring and summer, usually a few weeks later than A. similaris where the two species occur together. Records from the Pacific Northwest are from late May to early August.

Economic Importance

None.

Literature

Moth Photographers Group

Powell & Opler (2009)