Utiger, Helfenberger, Schatti, Schmidt, Ruf & Ziswiler (2002 Russian Journal of Herpetology 9(2): 105-124), using mtDNA, presented evidence that North American Rat Snakes of the genus Elaphe are a monophyletic lineage different from Old World members of the genus, and resurrected the available name Pantherophis Fitzinger for all North American (north of Mexico) taxa. Those adopting this generic name for the Eastern Corn Snake should be aware that spelling of the specific name changes to guttatus.
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