Distribution, Hybridization, and Taxonomic Status of Two-lined Salamanders (Eurycea bislineata complex) in Virginia and West Virginia

We used three diagnostic protein markers to examine salamanders of the Eurycea bislineata complex at 80 localities in Virginia and West Virginia. Two groups were strongly differentiated and met at a narrow contact zone. Rare hybridization was observed as well as limited introgression up to 5 km north and 10 km south of the contact zone. At the contact zone, 1% F1, 2% F2, 32% backcross, and 66% parental genotypes were observed. This pattern of parapatric distribution with limited hybridization and introgression argues for the recognition of Eurycea bislineata and E. cirrigera as separate species.