Schinia sexplagiata Smith, 1891
OR : Harney Co.
Little Cottonwood Cr., 4371 ft
July 20, 2001, Crabo/Troubridge.
Specimen courtesy of LGCC
Photograph copyright: Merrill A. Peterson
Schinia sexplagiata is a small to very small (FW length 9 - 11 mm), light olive-tan moth that flies in dunes in late summer. It has a dark wing base and subterminal area separated from the lighter median area by wide white lines. The forewing ground color is pale tan with a slight olive tint. The entire wing base proximal to the antemedial line and the subterminal line are darker, with the darkest parts of the subterminal area divided into similar size patches near the costa and trailing margin. The terminal area is slightly darker and grayer than the median area, with a concolorous fringe. The basal line is a pale patch on the costa near the wing base. The antemedial and postmedial lines are white and relatively wide, especially the antemedial line which is smoothly curved like a half-circle toward the outer margin. The postmedial line is wide on the costa, then thinner than the antemedial line across the rest of the wing. The portion lateral to the reniform spot is smoothly convex toward the outer margin or slightly squared-off, while the posterior portion is smoothly concave toward the wing base to meet the trailing margin angled slightly toward the base. The subterminal line is pale, white and wide at the costa and thinner and tan elsewhere, and slightly irregular. The only other marking is the reniform spot which is filled with gray-tan. The hindwing is pale whitish gray with dusty darker gray marginal band and diffuse discal spot. The hindwing fringe is white with a pale yellow base. The head is the same color and the median area and the thorax matches the darker wing base. The male antenna is filiform.
This species can be identified by its small size and distinctive pattern of three dark brown areas on a pale forewing with white lines. The pattern is most similar to that of Schinia biundulata, a smaller species that flies in similar habitats earlier in the year. It is even tan with white lines on the forewing, lacking contrasting darker areas.
This species is widely distributed on dry grasslands and sagebrush steppe at low elevations east of the Cascades, and may be locally common. It is associated with open dune habitats at some locations in the Columbia Basin.
Schinia sexplagiata is found in the dry interior of the Northwest as far north as southern Washington and the Idaho Panhandle. It has also been found in southeastern Oregon.
This species is found in a number of scattered localities in the Great Basin. It also occurs in northeastern and southern California and in the southern Great Plains from northeastern Colorado and Kansas to west Texas.
No information is presently available regarding larval foodplants of this species.
Adults fly in late summer and early autumn. The have been collected from mid-July through September and are most common in August. It is a nocturnal species that comes to lights.