Phylogeny of the leafhopper subfamily Deltocephalinae (Insecta: Auchenorrhyncha: Cicadellidae) and related subfamilies based on morphology

Abstract

Previous phylogenetic analyses of the leafhopper family Cicadellidae based on morphological and molecular data suggested that Deltocephalinae, as traditionally defined, is polyphyletic. These analyses recovered a large clade comprising Deltocephalinae and several other subfamilies. To further elucidate relationships within this large clade of deltocephaline‐like leafhoppers, an expanded dataset of 119 morphological characters and 68 taxa was compiled and analysed using cladistic methods. The taxon sample included one or more representatives of nearly all previously recognised tribes of Deltocephalinae, representatives of the non‐deltocephaline family‐group taxa which grouped with Deltocephalinae in previous analyses, and six putative outgroup taxa drawn from other cicadellid subfamilies. The resulting most parsimonious trees consistently recovered the putative ingroup as monophyletic. However, in agreement with previous analyses, most subfamilies and tribes represented by multiple exemplars were not resolved as monophyletic groups. Based on these results, subfamilies derived from within the deltocephaline lineage include Acostemminae, Arrugadinae, Drakensbergeninae, Eupelicinae, Koebeliinae, Mukariinae, Paraboloponinae, Penthimiinae, Selenocephalinae and Stegelytrinae. The phylogeny indicates that grass specialisation is much more phylogenetically conservative than implied by the current higher classification of leafhoppers. A list of synapomorphies on the strict consensus tree and an illustrated key to all family‐group taxa of deltocephaline‐like leafhoppers are provided.