Species Delimitation of Eastern Pinesnake Complex (Pituophis melanoleucus)

The eastern Pinesnake (Pituophis melanoleucus) is found throughout eastern United States. Taxonomy in this group has been controversial with several conflicting species designations. Three subspecies of the eastern Pinesnake have prevailed in the literature to their geographic locations and scale coloration: the northern Pinesnake (P. m. melanoleucus), the Florida Pinesnake (P. m. mugitus), and the Black Pinesnake (P. m. lodingi). Within the region, there are several major barriers to dispersal, particularly major river drainage systems and human modification of the longleaf pine habitat. Consistently, a lack of phylogenetic resolution has plagued these taxa in prior studies. The goal of this study was to examine the taxonomic validity of the eastern Pinesnake complex using single nucleotide polymorphisms (SNPs) isolated from ultra-conserved elements (UCEs) in phylogenetic and population genetic approaches. Molecular species delimitation approaches indicated that the population of eastern Pinesnake exhibits population structure across its range that may rise to the level of being new species.