Spotted grass moth

Spotted grass moth is an easily recognized, very small owlet moth. It occurs in the United States east of the Great Plains and in the Northwest, and across southern Canada. It is common in Minnesota. Adults are ⅜″ to 7 ⁄16″ (10 to 11 mm) in length and have a wingspan of ⅝″ to ¾″ (15 to 19 mm).

The forewings are pale yellow or straw-colored. There are scattered dark scales over the entire wing surface and there is usually at least some brown shading at the rear margin. A dark brown, often large patch surrounds a small purple kidney-shaped (reniform) spot and extends to the outer (costal) margin. Three narrow, parallel, brown or pale brown lines cross the wings: a W-shaped line separating the basal and median areas (antemedial line); a line separating the median and subterminal areas (postmedial line) that curves sharply, almost forming a loop near the costal margin; and a line on the rear margin at the base of the fringe (terminal line). The hindwing is slightly lighter. It has a terminal line and just a trace of a postmedial line.

The antennae are slender and thread-like.

Total length: ⅜″ to 7 ⁄16″ (10 to 11 mm)

Wingspan: ⅝″ to ¾″ (15 to 19 mm)

Meadows, moist grassy areas, woodland edges

May to August

Adults are active at night (nocturnal) and will come to lights. The wings are held flat when at rest.

Grasses