Garter & Ribbon Snakes Thamnophis   Fitzinger, 1843
An adult specimen of T. sirtalis from near Chillicothe, Ohio Image © John Mathews, 2006
Taxonomic Comments:
Alfaro and Arnold (2001 Molecular Phylogenetics and Evolution 21(3): 408-423), using mtDNA, presented evidence that this genus is monophyletic.