Adult moths of Erebidae have quadrifid forewings and usually quadrifine hindwings, meaning that each wing includes a cubital vein that splits into four (explained further in the Classification section).

[2] Among the Noctuoidea, the Erebidae can be broadly defined by the wing characteristics of the adults with support from phylogenetic studies.

The same splitting of the hindwing cubital vein has analogous terms bifine, trifine, and quadrifine.

Among the related families, most Erebidae are quadrifid moths like the Euteliidae, Nolidae, and Noctuidae and unlike the trifid Oenosandridae and Notodontidae.

[2][4][5] Phylogenetic studies in the present century have helped to clarify the relationships between the structurally diverse lineages within the Noctuoidea and within the Erebidae.

Morphological studies had led to a classification in which the monophyletic Arctiinae, Lymantriinae, and Micronoctuini were treated as families, and the other erebid lineages were largely grouped within the Noctuidae.

The determination of these phylogenetic relationships has led to the present classification scheme in which several clades were rearranged while kept mostly intact and others were split apart.

The rank of the Micronoctuini was changed from family to tribe to include the clade as a lineage within the Hypenodinae.