Systematics of the Leafhopper Subfamily Deltocephalinae (Hemiptera: Cicadellidae) and the Tribe Chiasmini: Phylogeny, Classification, and Biogeography

Based on the number of described species, the leafhopper subfamily Deltocephalinae is the largest subfamily of Cicadellidae, containing ∼850 genera and over 6200 described species. Chapter 1 provides a detailed introduction to this subfamily and to the tribe Chiasmini. Chapter 2 presents a phylogenetic analysis of Deltocephalinae and related subfamilies. The data set included 2814 aligned positions of the 28S rDNA gene region, 353 bp of the Histone H3 nuclear protein coding gene, and 119 morphological characters for 114 included exemplar species representing nearly all tribes of Deltocephalinae and related subfamilies and five outgroup taxa. The resulting phylogenetic trees showed strong support for many of the longer branches near the base and near the tips of the trees, but little support for the shorter internal branches. Nearly all of the grass/sedge specializing tribes were resolved in one relatively derived clade, and it appears that grass or sedge feeding was lost at least twice in this clade. Chapter 3 provides a history of the classification of Deltocephalinae over the past 60 years, and based on the analyses in Chapter 2, a revised classification of the subfamily and its tribes is proposed. Five taxa previously considered to be separate subfamilies (Acostemminae, Arrugadinae, Drakensbergeninae, Mukariinae, and Stegelytrinae) are considered synonyms of Deltocephalinae. The subfamily is redescribed and descriptions of all 36 included tribes and habitus images for most tribes are provided. Two new tribes, Faltalini and Scaphoideini, are described. Chapter 4 presents a molecular phylogenetic analysis of the grassland tribe Chiasmini (16 genera, 324 described species) and examines its biogeographic history. The classification of the tribe and its genera and the phylogeny and biogeographic scenarios for Exitianus proposed by Ross (1968) are tested with molecular data. Chiasmini was resolved in two well supported clades, each of which originated in the Old World. The New World species group of Exitianus is inferred to have colonized the New World through long distance dispersal from an ancestor in the Ethiopian region, and to have colonized South America first, then North America. The biogeographic history of the other New World chiasmines is less clear. In Chapter 5, the circumscription of Chiasmini is revised, a key to all included genera is provided, several generic synoymies are proposed, and 7 new species from the Old World are described.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Entomology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Zahniser, James Norman

Contributors dc:contributor

• Dietrich, Christopher H.

• Biology, Zoology

Language dc:language

eng

Identifier

(MiAaPQ)AAI3347585

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/86469