Grammia williamsii

Grammia williamsii, Williams' tiger moth, is a moth of the family Erebidae. It was described by Dodge in 1871. It is found from the Northwest Territories east to the northern Great Lakes region, New Brunswick and New England. It also occurs throughout the northern Great Plains, south at higher elevations to Arizona and New Mexico, west to south-eastern British Columbia and eastern California.

The length of the forewings is 14.9 mm. The ground colour of the forewings is chocolate brown to dark brown. The hindwings vary from dull orange-buff to pinkish buff or even yellowish. The markings are dark brown to black.

Larvae have been reared on a variety of forbs, and is probably a general feeder on herbaceous plants and grasses.