Systematics
In the now-obsolete classification that was used throughout much of the 20th century, the leafhoppers were part of the Homoptera", a paraphyletic assemblage uniting the less advanced lineages of Hemiptera and ranked as suborder. The splitting of the "Homoptera is likely to be repeated for the Auchenorrhyncha for similar reasons, as the Auchenorrhyncha simply seem to group the moderately advanced Hemiptera, regardless of the fact the highly apomorphic Coleorrhyncha and Heteroptera (typical bugs) evolved from auchenorrhynchans. Hence, there is a recent trend to treat the most advanced hemipterans as three or four lineages, namely Archaeorrhyncha (Fulgoromorpha if included in Auchenorrhyncha), Coleorrhyncha and Heteroptera (sometimes united as Prosorrhyncha) and Clypeorrhyncha.
Within the latter, the three traditional superfamilies – Cercopoidea (froghoppers and spittlebugs), Cicadoidea (cicadas) and Membracoidea – appear to be monophyletic. The leafhoppers are the most basal living lineage of Membracoidea, which otherwise include the families Aetalionidae (aetalionid treehoppers), Membracidae (typical treehoppers and thorn bugs), Melizoderidae and the strange Myerslopiidae.
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