Aseptis characta is a moth of the Noctuidae family. It is widespread in western North America, where it is found in the western Great Plains, Great Basin, and Pacific regions from British Columbia, Alberta, and Saskatchewan to Colorado, Utah, northern Arizona and southern California. The species occurs in dry habitats like sagebrush steppe, juniper woodlands, and open forest from sea level to 2,500 meters.
The wingspan is about 29.5–35 mm. The forewings are ash grey to pale tan, often darker grey in the medial area and with variable olive-grey, tan, or orange-tan patches. The basal, antemedial and postmedial lines are double, dark grey filled with pale grey. The postmedial area is lighter with a shade preceding the pale subterminal line and a number of black wedges between the veins. The three spots are outlined in black and are filled with the ground color and, except the claviform spot, peripheral lighter grey scales. The hindwing is grey, pale grey, or white with dark discal spot, veins, and terminal line, darker in females. Emergence is earliest in xeric habitats, usually April in California and mid-May in the Pacific Northwest. The flight lasts until July to August depending on locality.
The larvae feed on Artemisia species.