Pacific Northwest Moths

Identification

Adults

Lasionycta staudingeri is a small (FW length 10–13 mm) diurnal alpine moth with mottled dark gray forewings with olive patches and a white hindwing with black bands that has been found in southern Yukon Territory near the British Columbia border. The forewing is dark gray, usually with scattered yellow scales producing an olive appearance, strongest in the basal and terminal areas, paler gray or light olive terminal area, and white- or pale-gray-filled lines and spots. The black markings are obscure against the dark background, but the double antemedial and postmedial lines are relatively well-defined due to their pale filling, as are the spots. The antemedial line is slightly irregular. The postmedial line is strongly toothed on the veins, excurved around the cell then oblique to the posterior margin. The irregular subterminal line is most evident as the interface between the darker subterminal and lighter terminal areas. The fringe is strongly checkered black and white. The orbicular spot is filled with white or pale gray, lacking a dark central spot ("ocellus"). The reniform spot is relatively small and is similarly filled with pale. The claviform spot is a black smudge. The hindwing ground color is white with dark suffusion, usually limited to the base but occasionally diffuse. A variable-thickness scalloped medial line, wide marginal band, and thin discal spot are black. The hindwing fringe is pure white. The head and thorax are dark gray. The eye is covered by fine hairs. The male antenna is bipectinate, greater than twice the width of the central shaft.

In parts of the arctic Lasionycta leucocycla has a whitish hindwing and is the most similar moth to L. staudingeri. However, Pacific Northwest L. leucocycla have pale yellow hindwings and are unlikely to be confused with L. staudingeri. Similar closely-related congeners in our region, Lasionycta frigida and Lasionycta illima, differ from L. staudingeri in having a dark ocellus in the orbicular spot, lack olive color on the forewing, have an off-white hindwing with a relatively thick discal spot, and a two-toned hindwing fringe with a dark base. Sympistis zetterstedtii is a common alpine moth that could be mistaken for L. staudingeri; however, it lacks hairs on the eyes, has a glossy sheen to the wings, no olive color on the forewing, and its hindwing has a well-defined black marginal band on a white ground.

North American populations of this moth are assigned to subspecies L. s. preblei (Benjamin).

Habitat

This species occurs above treeline in the southern Yukon, preferring dry rocky tundra.

Distribution

Pacific Northwest

Lasionycta staudingeri has not yet been confirmed in the region but it occurs just north of the British Columbia border and is expected in the far northern part of the province.

Global

This is a circumpolar moth. It occurs north of the 60th parallel in North America as far east as Baffin Island. The range extends across northern Eurasia to Fennoscandia.

Life History

Larvae

The larva is described and illustrated by Lafontaine et al. (1986). It feeds on crowberry (Empetrum nigrum (Ericaceae)) but accepts other plants in captivity.

Adults

Adults are diurnal, flying from late June to mid-August depending on latitude, snow pack, and weather. The few specimens from southern Yukon were found during late June and early July.

Economic Importance

None.

Literature

Crabo LG, Lafontaine JD. 2009. A revision of Lasionycta Aurivillius (Lepidoptera, Noctuidae) for North America and notes on Eurasian species, with descriptions of 17 new species, 6 new subspecies, a new genus, and two new species of Tricholita Grote. ZooKeys 30: 1–156.

Lafontaine JD, Kononenko VS, McCabe TL. 1986. A review of the Lasionycta leucocycla complex (Lepidoptera: Noctuidae) with description of three new subspecies. The Canadian Entomologist 118: 255–279.

Moth Photographers Group