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The ability to accurately delimit species is of vital importance, particularly when dealing with taxa whose speciation is not immediately apparent. Phylogeographical analysis has emerged as a method that allows us to link micro and macroevolutionary processes in order to better understand speciation and divergence of sister taxa. Until recently, the Three-lined salamander (Eurycea guttolineata) was considered to be a subspecies of the Long-tailed Salamander (Eurycea longicauda). The most recent taxonomic analysis used both morphology and allozyme data to support the status of E. guttolineata as its own species. Our study aimed to produce a phylogenetic reconstruction of intraspecies variation across the range of E. guttolineata, with the intention of providing reliable data for future comparison studies of E. guttolineata and E. longicauda. Using mtDNA analyses of the cytochrome b (Cyt b) gene and Bayesian inference models, we produced a phylogenetic reconstruction of E. guttolineata. Additionally, we were able to compare cyt b haplotypes of E. guttolineata, and E. longicauda. Our analysis of E. guttolineata was characterized by a surprisingly low level of genetic diversity. This could potentially be due to a recent range expansion, or a large amount of gene flow between subpopulations throughout their range. Of utmost interest in our findings, was the identification of cyt b haplotypes characteristic of E. guttolineata in southern populations of E. longicauda (within the species contact zone). Further investigation of the species contact zone is needed, and hybridization frequencies in this zone may provide insights on determining parapatric speciation between these two species. [ABSTRACT FROM AUTHOR]

Pseudotriton is a genus of salamanders currently consisting of two species, P. montanus and P. ruber. Both species of Pseudotriton are endemic to a large portion of the southeastern United States. Recent research has demonstrated that P. ruber has been shown to be largely homogeneous throughout its range, and that the P. ruber subspecies do not reflect phylogenetic relationships. Pseudotriton montanus has been studied far less, its secretive nature, as a typically fossorial species makes it difficult to study throughout its relatively large range. There are four currently accepted subspecies of P. montanus. These subspecies include P.m. montanus, P.m. diasticus, P.m. flavissimus, and P.m. floridanus. The goal of this study is to survey the variability of P. montanus individuals sampled across their geographic range, and test whether the currently recognized subspecies represent independent evolutionary lineages. Here we present a phylogenetic reconstruction of the mtDNA gene, ND2, from populations sampled throughout the range of P. montanus. This data shows that P. montanus is far more divergent than P. ruber and suggests that P. montanus may consist of multiple species. [ABSTRACT FROM AUTHOR]

Recent work in our lab has uncovered multiple candidate species within the widely-distributed complex of the Northern Dusky salamander, Desmognathus fuscus. Evidence for genetic divergence includes both mitochondrial and nuclear sequence data. However, little is currently known about morphological differences among these newly-found lineages of D. fuscus. We conducted geometric morphometric analyses to check for variation. We assembled photographs of D. fuscus specimens, representing eight different mitochondrial clades, in tps file format and plotted twelve homologous landmarks on each image using the program tpsDig. We then produced a series of dorsal and ventral measurements using Morpheus software. In order to control for size, we converted the raw measurements into ratios, which we statistically analyzed in R software through independent sample t-tests comparing different lineages. Our analysis suggests that there are statistically significant examples of morphological deviation between some of these clades. [ABSTRACT FROM AUTHOR]

Scientists have been investigating the distribution and taxonomic status of Eurycea bislineata and have been applying molecular biology techniques since the 1980s. The three traditionally recognized subspecies are E. b. bislineata, E. b. cirrigera, and E. b. wilderae. Recent molecular research suggests that the current taxonomy of two line salamanders under represents the evolutionary diversity. However it is unclear which existing binomials should be applied to which populations of Eurycea. Here we focus on the taxonomic and distributional status of Eurycea wilderae by comparing topotypic material with populations collected throughout the range of E. b. cirrigera and E. b. wilderae. Our results suggest that the distribution of E. b. wilderae is vastly different from published range maps. Furthermore, our molecular phylogenetic reconstruction and statistical analysis of linear morphological measurements demonstrates unequivocally that most populations currently referred to as Eurycea wilderae are in fact other species. [ABSTRACT FROM AUTHOR]