INTEGRATED SPECIES DELIMITATION OF THE RINGNECK SNAKE DIADOPHIS PUNCTATUS IN A BIODIVERSITY HOTSPOT**
The California Floristic Province (CFP) is considered one of the world’s 25 most biologically rich and endangered terrestrial ecoregions harboring more plant species than the central and northeastern United States and Canada combined, as well as over 30% of the known insect species north of Mexico. Widespread species in the CFP also show pronounced fine-scale genetic differences among populations, possibly resulting from the adaptation of populations to local environments and other species. Species are fundamental units of study in evolutionary biology, ecology, and conservation research. Inaccurate understanding of species diversity may lead to errors in analyses that use species as units (e.g., phylogenetic community structure analyses), and may hinder conservation efforts. Throughout California, seven sub-species have been traditionally recognized within the ringneck snake genus Diadophis based on morphological characters. Recent molecular studies using mitochondrial DNA recognized three distinct lineages within the CFP, leading many herpetologists to abandon the traditional morphologically-based subspecies. In this study, we take an integrative approach to species delimitation by combining genetic data from two mitochondrial genes, 6 nuclear loci and continuous morphological characters to assess the species diversity within the ringneck snake genus Diadophis distributed throughout the CFP. We jointly analyzed morphological and molecular data in a common coalescent Bayesian framework using the program iBPP. This method has been shown to improve the accuracy of species delimitation by integrating phenotypic and genetic data. The iBPP analysis was performed with and without mtDNA data to maximize the signal derived from phenotypic variation and to evaluate the influence of mtDNA sequence data on this integrated analysis. Our results provide new insights into the biodiversity of Diadophis within the CFP, and we highlight the importance of combining traditional character-based descriptions with computational genetic methods for species delimitation.
University of West Georgia, Dept. of Biology
Strott*, Polly and Fontanella, Frank M.
"INTEGRATED SPECIES DELIMITATION OF THE RINGNECK SNAKE DIADOPHIS PUNCTATUS IN A BIODIVERSITY HOTSPOT**,"
Georgia Journal of Science, Vol. 76, No. 1, Article 111.
Available at: https://digitalcommons.gaacademy.org/gjs/vol76/iss1/111