Pantherophis emoryi – Wikipedia

Species of snake

Pantherophis emoryi
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Colubridae
Genus: Pantherophis

P. emoryi

Binomial name
Pantherophis emoryi

Pantherophis emoryi, commonly known as the Great Plains rat snake, is a species of nonvenomous rat snake native to the central part of the United States, from Missouri to Nebraska, to Colorado, south to Texas, and into northern Mexico.


The epithet, emoryi, is in honor of Brigadier General William Hemsley Emory, who was chief surveyor of the U.S. Boundary Survey team of 1852 and collected specimens for the Smithsonian Institution.[3] As such, it is sometimes referred to as Emory’s rat snake.

Common names[edit]

Additional common names for Pantherophis emoryi include the following: brown rat snake, chicken snake, eastern spotted snake, Emory’s Coluber, Emory’s pilot snake, Emory’s racer, Emory’s snake, gray rat snake, mouse snake, prairie rat snake, spotted mouse snake, Texas rat snake, and western pilot snake.[4]


The Great Plains rat snake is typically light gray or tan in color, with dark gray, brown, or green-gray blotching down its back, and stripes on either side of the head which meet to form a point between the eyes. They are capable of growing from 3 feet to 5 feet long.


Great Plains rat snakes prefer open grassland or lightly forested habitats, but are also found on coastal plains, semi-arid regions, as well as rocky, moderately mountainous regions. They can often be found on farmland, which often leads it to be erroneously called the chicken snake, and other areas with a relatively high rodent population, which is their primary diet. They will also eat birds, and occasionally snakes, lizards and frogs, all of which they subdue by constriction. They are primarily nocturnal, and oviparous, laying clutches of as many as 25 eggs in the late spring. Like most rat snakes, when agitated, the Great Plains rat snake will shake its tail vigorously, which by itself makes no noise, but when it shakes amongst dry leaf litter, it can sound remarkably like a rattlesnake, and often leads to misidentification. Great Plains rat snakes tend to remain still for a majority of their time awake, which is odd for a nocturnal being. On average, the Great Plains snakes only move 188 meters per day. The Yellow-Bellied Racers, a snake that often lives in the same habitat, moves more often than the Great Plains snake – which could lead to a decline in their population as they are not as mobile.[5]

Warning signs of agitation are curling up tightly, shaking its tail rapidly. Though this snake has very small teeth and is nonvenomous, it will bite. However, as a whole, this species of snake is very calm and non-aggressive.


This species, Pantherophis emoryi, has undergone extensive reclassification since it was first described by Spencer Fullerton Baird and Charles Frédéric Girard in 1853 as Scotophis emoryi. It has often been placed in the genus Elaphe, but phylogenetic analyses performed in the 2000s have resulted in its transfer to Pantherophis.[6][7][8]

Pantherophis emoryi has been elevated to full species status and downgraded to a subspecies of Pantherophis guttatus multiple times. Most recently, Burbrink suggested that Pantherophis guttatus be split into three species: Pantherophis guttatus, Pantherophis emoryi, and Pantherophis slowinskii.[9]

The most recent taxonomic paper on this species complex refutes Burbrink’s species suggestions based on more comprehensive sampling and genetic work. “Our data support a revision of the taxonomy of this group, and we recognize two species within the complex and three subspecies within P. emoryi. This study illustrates the importance of thorough sampling of contact zones and consideration of gene flow when delimiting species in widespread complexes containing parapatric lineages.”[10]


  1. ^ Hammerson, G.A. (2007). Pantherophis emoryi. IUCN Red List of Threatened Species. 2007: e.T63861A12723067. doi:10.2305/IUCN.UK.2007.RLTS.T63861A12723067.en. Retrieved 19 November 2021.
  2. ^ Pantherophis emoryi at the Reptile Database. Accessed 29 March 2021.
  3. ^ Beolens B, Watkins M, Grayson M (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN 978-1-4214-0135-5. (Pantherophis emoryi, pp. 83-84).
  4. ^ Wright AH, Wright AA (1957). Handbook of Snakes of the United States and Canada. Ithaca and London: Comstock. 1,105 pp. (in 2 volumes) (Elaphe emoryi emoryi, pp. 218-223, Figure 68, Map 23).
  5. ^ Klug, Page E.; Fill, Jennifer & With, Kimberly A. (2011). “Spatial ecology of eastern yellow-bellied racer (Coluber constrictor flaviventris) and Great Plains rat snake (Pantherophis emoryi) in a contiguous tallgrass-prairie landscape”. Herpetologica. 67 (4): 428–439. doi:10.1655/HERPETOLOGICA-D-10-00076.1. S2CID 3065840.
  6. ^ Utiger, Urs; Helfenberger, Notker; Schätti, Beat; Schmidt, Catherine; Ruf, Markus & Ziswiler, Vincent (2002). “Molecular systematics and phylogeny of Old and New World ratsnakes, Elaphe Auct., and related genera (Reptilia, Squamata, Colubridae)”. Russian Journal of Herpetology. 9 (2): 105–124. doi:10.30906/1026-2296-2002-9-2-105-124 (inactive 28 February 2022).{{cite journal}}: CS1 maint: DOI inactive as of February 2022 (link)
  7. ^ Burbrink, Frank T. & Lawson, Robin (2007). “How and when did Old World ratsnakes disperse into the New World?”. Molecular Phylogenetics and Evolution. 43 (1): 173–189. doi:10.1016/j.ympev.2006.09.009. PMID 17113316.
  8. ^ Pyron, R. Alexander & Burbrink, Frank T. (2009). “Neogene diversification and taxonomic stability in the snake tribe Lampropeltini (Serpentes: Colubridae)”. Molecular Phylogenetics and Evolution. 52 (2): 524–529. doi:10.1016/j.ympev.2009.02.008. PMID 19236930.
  9. ^ Burbrink, F (2002). “Phylogeographic analysis of the cornsnake (Elaphe guttata) complex as inferred from maximum likelihood and Bayesian analyses”. Molecular Phylogenetics and Evolution. 25 (3): 465–476. doi:10.1016/S1055-7903(02)00306-8. PMID 12450751.
  10. ^ Marshall, Thomas L.; Chambers, E. Anne; Matz, Mikhail V.; Hillis, David M. (September 2021). “How mitonuclear discordance and geographic variation have confounded species boundaries in a widely studied snake”. Molecular Phylogenetics and Evolution. 162: 107194. doi:10.1016/j.ympev.2021.107194. PMID 33940060.

Further reading[edit]

  • Baird SF, Girard CF (1853). Catalogue of North American Reptiles in the Museum of the Smithsonian Institution. Part I.—Serpents. Washington, District of Columbia: Smithsonian Institution. xvi + 172 pp. (Scotophis emoryi, new species, pp. 157–158).
  • Conant R (1975). A Field Guide to Reptiles and Amphibians of Eastern and Central North America, Second Edition. Boston: Houghton Mifflin. xviii + 429 pp. + Plates 1-48. ISBN 0-395-19979-4 (hardcover), ISBN 0-395-19977-8 (paperback). (Elaphe guttata emoryi, pp. 191–192, Figures 43-44 + Pl 28 + Map 150).
  • Smith HM, Brodie ED Jr (1982). Reptiles of North America: A Guide to Field Identification. New York: Golden Press. 240 pp. ISBN 0-307-13666-3. (Elaphe guttata emoryi, pp. 184–185).

External links[edit]