Points of View on Defining and Naming Species of Plethodontid Salamanders

Abstract

A symposium, consisting of five papers presented by Darrel Frost, Richard Highton, David Wake, Stephen Tilley, and Paul Chippindale, was held on 13 June 1998 during The Fourth Highlands Conference on the Biology of Plethodontid Salamanders, at Highlands, North Carolina. The purpose of the symposium was to honor Professor Richard Highton (see Frontispiece) upon his retirement from the faculty at The University of Maryland at College Park. I first met Dick Highton 40 years ago when I was an undergraduate student at that university. During those 40 years, Dick’s research has had a tremendous impact on current views of the systematics of salamanders of the family Plethodontidae. His identification of many sibling species within the genus Plethodon, in particular, has not only stimulated considerable ecological and behavioral research within and between species in that genus, but also has raised questions about what criteria should be used in defining species of plethodontid salamanders, especially for allopatric populations. For example, a difference of opinions concerning the taxonomy of the genus Ensatina can be found in two recent publications: Highton (1998) and Wake and Schneider (1998). Because of the current debate over methodology in systematic analyses, this symposium was entitled Points of View on Defining and Naming Species of Plethodontid Salamanders. The first paper, by Darrel Frost, dealt with broader philosophical issues of species’ identification; the subsequent four papers focused more specifically on empirical studies of systematics. The last paper, by Stevan Arnold, summarizes the current status of plethodontid systematics.