''Pantherophis emoryi'',
commonly known as the Great Plains rat snake, is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of non
venom
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...
ous
rat snake
Rat snakes are members – along with kingsnakes, milk snakes, vine snakes and indigo snakes – of the subfamily Colubrinae of the family Colubridae. They are medium to large constrictors and are found throughout much of the Northern Hemisph ...
in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Colubridae
Colubridae (, commonly known as colubrids , from la, coluber, 'snake') is a family of snakes. With 249 genera, it is the largest snake family. The earliest species of the family date back to the Oligocene epoch. Colubrid snakes are found on ever ...
. The species is native to the central part of the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
, from
Missouri
Missouri is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it is bordered by eight states (tied for the most with Tennessee ...
to
Nebraska
Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwe ...
, to
Colorado
Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...
, south to
Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...
, and into northern
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
.
Etymology
The
epithet
An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, di ...
, ''emoryi'', is in honor of Brigadier General
William Hemsley Emory
William Hemsley Emory (September 7, 1811 – December 1, 1887) was a prominent American surveyor and civil engineer in the 19th century. As an officer in the U.S. Army Corps of Topographical Engineers he specialized in mapping the United States b ...
, who was chief surveyor of the U.S. Boundary Survey team of 1852 and collected specimens for the
Smithsonian Institution
The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums and education and research centers, the largest such complex in the world, created by the U.S. government "for the increase and diffusion of knowledge". Founded ...
. As such, it is sometimes referred to as Emory's rat snake.
Common names
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.
Description
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. It is capable of growing to in total length (including tail).
Habitat and behavior
The Great Plains rat snake prefers open
grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
or lightly
forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
ed habitats, but is also found on coastal plains, semi-arid regions, as well as rocky, moderately mountainous regions. It can often be found on farmland, which often leads to its being erroneously called a
chicken snake, and other areas with a relatively high
rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...
population, which is its primary
diet
Diet may refer to:
Food
* Diet (nutrition), the sum of the food consumed by an organism or group
* Dieting, the deliberate selection of food to control body weight or nutrient intake
** Diet food, foods that aid in creating a diet for weight loss ...
. It will also eat
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
s, and occasionally snakes,
lizard
Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...
s and
frog
A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...
s, all of which it subdues by
constriction
Constriction is a method used by various snake species to kill or subdue their prey. Although some species of venomous and mildly venomous snakes do use constriction to subdue their prey, most snakes which use constriction lack venom. The snake i ...
. It is primarily
nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
, and
oviparous
Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...
, laying
clutches
A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). ...
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
The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, r ...
vigorously, which by itself makes no noise, but when it shakes among dry leaf litter, it can sound remarkably like a
rattlesnake
Rattlesnakes are venomous snakes that form the genera ''Crotalus'' and ''Sistrurus'' of the subfamily Crotalinae (the pit vipers). All rattlesnakes are vipers. Rattlesnakes are predators that live in a wide array of habitats, hunting small anim ...
, and often leads to misidentification. The Great Plains rat snake tends to remain still for a majority of its time awake, which is odd for a nocturnal being. On average, the Great Plains rat snake only moves per day. The
yellow-bellied racer (''Coluber constrictor flaviventris''), a snake that often lives in the same habitat, moves more often than the Great Plains rat snake, which could lead to a decline in the Great Plains rat snake's population as it is not as mobile.
Warning signs of agitation are curling up tightly and shaking its tail rapidly. Though ''P. emoryi'' has very small teeth and is nonvenomous, it will bite. However, as a whole, this species of snake is very calm and non-aggressive.
Taxonomy
This species, ''Pantherophis emoryi'', has undergone extensive reclassification since it was first described by
Spencer Fullerton Baird
Spencer Fullerton Baird (; February 3, 1823 – August 19, 1887) was an American naturalist, ornithologist, ichthyologist, Herpetology, herpetologist, and museum curator. Baird was the first curator to be named at the Smithsonian Institution. He ...
and
Charles Frédéric Girard
Charles Frédéric Girard (8 March 1822 – 29 January 1895) was a French biologist specializing in ichthyology and herpetology.
Born in Mulhouse, France, he studied at the College of Neuchâtel, Switzerland, as a student of Louis Agassiz. In ...
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''.
''P. emoryi'' has been elevated to full species status and downgraded to a subspecies of ''
P. guttatus'' multiple times. Most recently, Burbrink suggested that ''P. guttatus'' be split into three species: ''P. guttatus'', ''P. emoryi'', and ''
P. slowinskii''.
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."
References
Further reading
*
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).
*
Behler JL,
King FW (1979). ''The Audubon Society Field Guide to North American Retiles and Amphibians''. New York: Alfred A. Knopf. 743 pp. . (''Elaphe guttata emoryi'', p. 605).
*
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. (hardcover), (paperback). (''Elaphe guttata emoryi'', pp. 191–192, Figures 43-44 + Pl 28 + Map 150).
*
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., 47 color plates, 207 figures. . (''Pantherophis emoryi'', p. 387 + Plate 36 + Figures 161, 180).
*
Smith HM,
Brodie ED Jr (1982). ''Reptiles of North America: A Guide to Field Identification''. New York: Golden Press. 240 pp. . (''Elaphe guttata emoryi'', pp. 184–185).
External links
Rat Snakes of North America: Great Plains Rat SnakeUtah's Hogle Zoo: The Great Plains Rat Snake
{{DEFAULTSORT:Pantherophis Emoryi
Pantherophis
Snakes of North America
Reptiles of the United States
Reptiles of Mexico
Fauna of the Great Plains
Fauna of the Plains-Midwest (United States)
Reptiles described in 1853
Taxa named by Spencer Fullerton Baird
Taxa named by Charles Frédéric Girard