Splitting up a complex mess: The effectiveness of statistical analysis on delimiting species complexes

Recent studies have highlighted a need for more refined tools in species delimitation. This is especially true when considering diversity within species complexes, where members are morphologically similar and traditional tools have thus far failed to provide clearly defined boundaries between species. This project seeks to refine our traditional tools of species delimitation and apply new tools to the challenges created by species complexes. The focus organisms of this study are the anurans of the Limnonectes kuhlii complex. This species complex comprises more than 25 species of stream frogs from Southeast Asia. Traditionally, morphometrics (particularly linear measures) has been the most common way to demonstrate differences between two or more species. Unfortunately, traditional morphological analyses placed members of this group into a single, widely distributed species for nearly 200 years. Recent studies combining genetic, morphological, and bioacoustic tools have been effective in distinguishing and delimiting some, but not all potential species of the L. kuhlii complex. The currently distinguished, yet undescribed, members (candidate species) provide an opportunity to investigate new approaches to morphological character analyses (e.g., geometric morphometrics), and to refine traditional approaches (alternative statistical analyses) used in species delimitation. Geometric morphometrics show statistically significant differences in head shape between candidate species. Statistics provided a refinement of the traditional morphological approaches and revealed a list of potential characters for delimiting the candidate species on Borneo. This study showed the use of Body Length (BL), recommended by Inger (1966), provided the same results as Snout-vent Length. Illustrating that BL should be considered throughout the complex, especially when previous studies have shown SVL between males and females of the same candidate species (or clade). BL may provide further insight to the candidate species on mainland by ...