Taxonomists have debated whether the complex of long-tailed shrews adapted to talus slope formations in the Appalachian Mountain range in eastern North America should be considered 1 species (Sorex dispar) or 2 species (S. dispar and S. gaspensis). Recent analyses of mitochondrial DNA and morphological data have suggested that these 2 taxa should be considered conspecifics. To help resolve this debate, a combination of mitochondrial (cytochrome-b [Cytb] sequence data) and nuclear markers (inter–SINE fingerprinting [where SINE is short interspersed element]) markers was analyzed from specimens collected from across the range of this complex, including the zone of contact between these putative species. Here we present our analyses of Cytb sequences and inter-SINE fingerprinting data that supports recognizing a single species composed of a monophyletic group of genetically highly similar shrews. Both data sets support the hypothesis of a single, relatively rapid expansion following the retreat of the Laurentide ice sheet, and the possibility of a northern refugium. We recommend recognizing these 2 taxa as conspecific, with S. dispar having nomenclatural priority.