. (Thamnophis proximus, pp. 428–429 + Plate 42). Rossman DA (1963). "The Colubrid Snake Genus Thamnophis: A Revision of the sauritus Group". Bulletin of the Florida State Museum 7 (3): 99–178. Say T (1823). In: James E (1823). Account of an Expedition from Pittsburgh to the Rocky Mountains, Performed in the Years 1819 and '20, by Order of the Hon. J.C. Calhoun, Sec'y of War: Under the Command of Major Stephen H. Long. From the Notes of Major Long, Mr. T. Say, and other Gentlemen of the Exploring Party. Vol. I. Philadelphia: H.C. Carey and I. Lea. 503 pp. (Coluber proximus, new species, p. 187). Smith HM, Brodie ED Jr (1982). Reptiles of North America: A Guide to Field Identification. New York: Golden Press. 240 pp. (paperback), (hardcover). (Thamnophis proximus, pp. 146–147). proximus Extant Cenozoic first appearances Reptiles of Belize Reptiles of Costa Rica Reptiles of El Salvador Reptiles of Guatemala Reptiles of Honduras Reptiles of Mexico Reptiles of Nicaragua Reptiles of the United States Reptiles described in 1823 Taxa named by Thomas Say