I wish to thank first Dr. K.G.A. "Andy" Hamilton, an entomologist at the Canadian National Collection of Insects in Ottawa. Dr. Hamilton provided many identifications for me, taught me the differences between the various groups, and generally got me interested in hoppers.
Other experts in Cicadas, Leafhoppers, Planthoppers, Treehoppers, and Spittlebugs have provided me help over the years. These include Dmitry Dmitriev, C.H. Dietrich, and James Zahniser of the Illinois Natural History Survey; Daniela M. Takiya of Universidade Federal do Paraná, Brasil; Lois B. O'Brien, Visiting Scholar at the University of Arizona; Charles Bartlett of the University of Delaware; Gervasio Silva Carvalho of Pontificia Universidade Católica do Rio Grande do Sul.; Paul Freytag of the University of Kentucky; Albino Sakakibara of the Universidade Federal do Paraná; Allen F. Sanborn of Barry University; Vinton Thompson, president of the Metropolitan College of New York. Scholars Gerry Bunker and Bill Reynolds have provided a great deal of help by identifying cicada adults and nymphs. We also thank Werner Holzinger for his invaluable help with planthopper identifications. For life history data, no one has been more helpful and more generous with their knowledge than Stephen Wilson of the University of Central Missouri, and J.E. McPherson of Southern Illinois University at Carbondale.
In developing the species pages I have mined a number of scholarly articles old and new, and these are listed in the Works Consulted page for Auchenorrhycha.
Above all, I want to thank my many friends and colleagues at the Bugguide.net website, who help with IDs, provide stimulating conversation about hexapods, and mutual support. Many of these are listed in the overall Acknowledgments page for the American Insects site.