A common classification of the Lepidoptera involves their differentiation into butterflies and moths. Butterflies are a natural monophyletic group, often given the suborder Rhopalocera, which includes Papilionoidea (true butterflies), Hesperiidae (skippers), and Hedylidae (butterfly moths). In this taxonomic scheme, moths belong to the suborder Heterocera. Other taxonomic schemes have been proposed, the most common putting the butterflies into the suborder Ditrysia and then the "superfamily" Papilionoidea and ignoring a classification for moths.