Maria Boyle. 2005. Genetic distinctiveness of a peripheral Illinois population of the southern two-lined salamander (Eurycea cirrigera). Masters Thesis. Department of Biological Sciences, Chicago State University, Chicago, Illinois.

Abstract The southern two-lined salamander (Eurycea cirrigera) is a predominantly southeastern North American species whose peripheral range extends into eastern Illinois. An isolated popula-tion inhabits tributaries of the Kankakee River within and near the Kankakee River State Park (KRSP) in Will County, Illinois: the northwestern-most extent of its known range. Using seven microsatellite loci developed for the red-backed salamander (Plethodon cinereus), the genetic variability of the KRSP population was compared with nearby populations in Warren County, Indiana (WC) and a distant population in Aiken County, South Carolina (AC). Pair-wise com-parisons indicated significant differences at all loci between the KRSP and AC samples and sig-nificant differences in six out of seven loci between KRSP and WC population samples. There was a significant correlation (r² = 0.96) between the mean genetic and geographical distance over all population locations. Differentiation within the KRSP samples demonstrated significant variability at three of the seven loci, with pair-wise comparisons of Fst (correlation measurement of genetic difference between pairs of populations) showing significant genetic differences in eight out of ten population matches, including two of three site comparisons on the north and south sides of the Kankakee River, suggesting that the river forms an isolating boundary between these locations.