Gray ratsnake

A medium to large serpent, the gray ratsnake typically reaches an adult size of 99–183 cm (3.25–6.00 ft) total length (including tail); however, the record is 247 cm (8.10 ft) for a captive specimen at the Ridley 4-H Center in Tennessee. Unlike other Pantherophis, whose conspicuous juvenile pattern fades into adulthood, the gray ratsnake in the southern part of its range does not undergo drastic ontogenetic changes in color or markings. Instead, it retains the juvenile pattern of dark elongate dorsal blotches separated by four, or more, pale gray body scales, a light gray crown with dark striping that forms an anteriorly facing spearpoint, and a solid band which covers the eyes and extends rearward to the posterior upper labial scales. However, in the northern part of its range it is black in adulthood, like P. alleghaniensis and P. obsoletus. The venter is usually off-white or pale gray with darker irregular blotches, and a double row of black spots behind the divided anal plate of the vent. The dorsal scale rows around midbody are usually weakly keeled. Because the gray ratsnake shares its range with other members of its genus, hybrids of midlands x eastern ratsnakes are not uncommon.

Native to North America, Pantherophis spiloides is commonly found in the forests of the eastern and central United States. It occurs relatively continuously throughout the major part of the eastern half of the United States, along the western edge of the Appalachian Mountains, from southwestern New England to the Gulf of Mexico, westward to the Mississippi River, and northward from northern Louisiana to southwestern Wisconsin.

In Canada, this species is known to occur in two disjunct regions of southern Ontario: the Carolinian forest region along the north shore of Lake Erie in the southwest, and the Great Lakes/St. Lawrence region in the southeast.[5][6][7]

The gray ratsnake is considered common across much of its range, but is listed as "of special concern" in Michigan[8] and is also listed as rare in Wisconsin.[9] The gray ratsnake is listed federally in Canada as "endangered" (Carolinean population) and "threatened" (Great Lakes – St. Lawrence population).[10][7] In the state of Georgia, all indigenous, nonvenomous snakes are illegal to kill or capture, and are considered to be in the custody of the Georgia Department of Natural Resources.[11]

Habitat destruction and road mortality are leading causes of decline.[7]

• Powell R, Conant R, Collins JT (2016). Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition. Boston and New York: Houghton Mifflin Harcourt. xiv + 494 pp. ISBN 978-0-544-12997-9. (Pantherophis spiloides, pp. 389–390 + Figure 161 on p. 334 + Plate 36 on p. 335 + Map on p. 385 + Figure 180 on p. 386).