See text Euparthenos is a monotypic moth genus in the family Erebidae erected by Augustus Radcliffe Grote in 1876.

[1] The adults resemble some of the underwing moths of genus Catocala, which are fairly close relatives, in color, pattern, and the habit of resting on tree trunks.

But E. nubilis can usually be immediately recognized by the four concentric black bands per hindwing, as opposed to one or two (at most three) in Catocala.

Color morphs of E. nubilis with altered pattern are known, however, and these may be hard to recognize without detailed examination.

[3] The species is found in North America from Maine, Ontario and Quebec, south to northern Florida, west to Nebraska and Arizona.