This species was formerly known as Elaphe guttata. Recent phylogenetic studies have suggested that the name Pantherophis guttatus should be applied to this species, New World rat snakes appear to be more closely related to species of the tribe Lampropeltini (which includes kingsnakes) rather than Old World rat snakes (for which the generic name Elaphe still applies).
Corn snakes have few natural predators, mostly larger snakes and birds of prey. Carnivorous mammals may also eat corn snakes. Larger snakes, such as eastern kingsnakes and black racers, will consume corn snakes. A corn snake’s primary method of avoiding predators is by camouflage and fleeing from danger. Juveniles hide from predators under tree bark.
Known Predators:
Anti-predator Adaptations: cryptic
Corn snakes are mild-tempered, non-venomous snakes. Large spots run along dorsal side of the body, while the flat underside commonly has a black and white checkered pattern. The body tends to be brown and red-orange, but colors vary with region and can include gray and yellow. In captivity, breeders have created a wide variety of color patterns, or morphs. Pet corn snakes range in color from white to yellow to black, though most still retain the primary red/brown colors. Captive patterns include spots, stripes, and solid coloring over the snake's body. Males are larger than females, with an average length of 70 to 120 cm for the combined sexes. Snakes in warmer climates tend to be shorter, with an average adult length of approximately 48 cm. Hatchlings are paler and duller when they first hatch, and measure 20 to 35 cm.
Corn snakes can sometimes be confused with venomous southern copperheads (Agkistrodon contortrix), but the two can be differentiated by the narrower head, lighter coloration, and square-shaped spots that are found in red corn snakes.
Range length: 48 to 120 cm.
Other Physical Features: heterothermic
Sexual Dimorphism: male larger
Average mass: 900 g.
The longest recorded lifespan of this species in captivity was just over 32 years. Although no information on lifespan in the wild is currently available, it can be reasonably assumed that predation and disease cause wild individuals to have shorter average lifespans.
Range lifespan
Status: captivity: 32.3 (high) years.
Average lifespan
Status: captivity: 32.3 years.
Corn snakes can be found in a wide variety of terrestrial habitats, preferring deciduous forests and rocky regions where crevices and logs provide nests. They can also be found in fields, grassy areas, and in suburban areas near homes and barns. This species has been found in mountainous regions up to about 1800 m in elevation but typically prefer lower elevations.
Range elevation: 1800 (high) m.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest
Other Habitat Features: suburban
Corn snakes are found throughout the eastern and southern central United States, into northern Mexico. Two subspecies, Pantherophis guttatus guttatus (corn snake) and P. guttatus emoryi (Great Plains rat snake) are currently recognized. Corn snakes are found from southern New Jersey to Florida and westward through Mississippi to Louisiana. The range of Great Plains rat snakes extends from southwestern Illinois through Texas and into northern Mexico, and as far west as eastern New Mexico.
Biogeographic Regions: nearctic (Native )
Corn snakes are carnivorous and do not need to eat often. They eat every few days in the wild. They kill prey by constriction and consume anything smaller than they are, including other corn snakes. Over half of their diet consists of rodents such as hispid cotton rats, white-footed mice and other mammal prey, such as eastern moles. In Florida, their diet consists mainly of reptiles and amphibians, which this may be a cause for this region's smaller snake sizes. Corn snakes will also climb trees and swallow bird eggs from unguarded nests.
Animal Foods: birds; mammals; amphibians; reptiles; eggs
Primary Diet: carnivore (Eats terrestrial vertebrates)
The biggest impact that corn snakes have on their ecosystem is their ability to control populations of small mammals and birds. Several species of apicomplexan parasites infect corn snake blood cells, liver, and lung tissue. Hepatozoon guttata (named for its host) is thought to be exclusive to red corn snakes and has been identified in individuals from southeast Florida. It is not known how the parasites spread from individual to individual.
Commensal/Parasitic Species:
Like many snake species, corn snakes play a vital role in controlling rodent populations, helping to prevent the spread of disease and crop damage in areas inhabited by humans. Corn snakes are also popular pets for reptile enthusiasts. Breeders have developed a variety of color morphs for the pet market. They are easy to care for if proper attention is paid to setting up their terrarium (dry, clean, with an area set up for them to bask under a heat lamp) and are generally safe for families with children. As pets, corn snakes are fed high protein diets consisting mainly of mice and rats, although day-old chicks have been shown to provide similar nutrition.
Positive Impacts: pet trade ; controls pest population
Although a corn snake's preferred defense is to flee, cornered snakes will bite humans.
Negative Impacts: injures humans (bites or stings)
Juvenile corn snakes are fully developed when hatched. This species has ZZ/ZW sex determination, with the male snake contributing only Z chromosomes, while the female contributes the Z or W chromosome that determines the gender of the hatchlings (ZZ=male, ZW=female).
As they grow, juvenile corn snakes shed their skin several times, and will continue to shed after reaching adulthood. After shedding, the coloration of the scales turns more vivid and the patterns become clearer. Growth is directly related to how much food is available to the snake; juveniles grow faster on a regular diet of warm-blooded animals. In general, a juvenile reaches its full length shortly after reaching sexual maturity, at around two years of age.
Development - Life Cycle: indeterminate growth
Although some natural habitat has been lost to human development, corn snakes show no sign of being a threatened species.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
Corn snakes have rather poor eyesight and depend mainly on olfaction to perceive their environment. Like other snakes, their tongues, in conjunction with the Jacobson's organ in the roof of the mouth, detect scent molecules in the surrounding environment. In addition to the presence of these scents, corn snakes can also determine the direction from which the molecules were released. Corn snakes can also feel ground vibrations throughout their body, which are used to locate small or otherwise hidden prey or predators. Although they have no external ears, snakes have well-developed, functioning inner ears. When sound waves contact a snake's skin, the vibration is conducted through the bones of the jaw to the cochlea. Each of the jaws functions independent of the other in this respect, effectively allowing stereo hearing and directional sound location.
Corn snakes communicate in the same ways as most other species of snake. During the mating season, males give off pheromones that are detected by females. Communication is rare outside of mating season, as they are solitary animals.
Communication Channels: tactile ; chemical
Other Communication Modes: pheromones
Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical
Not much is known about the mating systems of corn snakes. During mating season, the snakes locate each other using pheromones. Males fight each other for dominance, with the dominant male earning mating rites to the female.
Mating System: polygynous
Corn snakes reach sexual maturity at 16 to 18 months of age. Depending on the climate, the breeding season lasts from March to May, or year-round in the south. Gestation lasts one to two months, with females laying 10 to 15 (up to 30) eggs from May to early July in stumps, logs, or burrows that are warm and humid. The eggs are white and cylindrical, measuring 3.8 to 6.4 cm in length and 1.3 to 2.5 cm in diameter. Finding a corn snake nest is very rare, because females seek out secluded nesting sites. After approximately two months of incubation at an ideal temperature of 27.8 degrees Celsius, the eggs hatch between July and September. Not all healthy eggs hatch, as some hatchlings cannot penetrate the tough eggshell.
Females in the wild lay one clutch of eggs per year. In captivity, female corn snakes may lay a second clutch of eggs. If a female snake breeds a second time, she can produce fertile eggs within days of laying her first clutch. She will lay her second clutch following the same timeline as the first.
Breeding interval: Wild corn snakes breed once annually.
Breeding season: Snakes mate in spring; eggs hatch during the summer.
Range number of offspring: 10 to 30.
Average number of offspring: 10-15.
Range gestation period: 35 to 68 days.
Range age at sexual or reproductive maturity (female): 16 to 18 months.
Range age at sexual or reproductive maturity (male): 16 to 18 months.
Key Reproductive Features: iteroparous ; seasonal breeding ; year-round breeding ; sexual ; fertilization ; oviparous
Average number of offspring: 12.
Corn snakes provide no care to their young. Male snakes leave the female after mating, and females leave their eggs after laying them in a secluded nest.
Parental Investment: no parental involvement; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female)
The corn snake (Pantherophis guttatus), sometimes called red rat snake, is a species of North American rat snake in the family Colubridae. The species subdues its small prey by constriction.[4][5] It is found throughout the southeastern and central United States. Though superficially resembling the venomous copperhead (Agkistrodon contortrix) and often killed as a result of this mistaken identity, the corn snake lacks functional venom and is harmless. The corn snake is beneficial to humans[6] because it helps to control populations of wild rodent pests that damage crops and spread disease.[7]
The corn snake is named for the species' regular presence near grain stores, where it preys on mice and rats that eat harvested corn (maize).[8] The Oxford English Dictionary cites this usage as far back as 1675, whilst other sources maintain that the corn snake is so-named because the distinctive, nearly-checkered pattern of the snake's belly scales resembles the kernels of variegated corn.[9][10]
The corn snake is also referred to as a red rat snake.[11]
As an adult the corn snake may have a total length (including tail) of 61–182 cm (2.00–5.97 ft).[12] In the wild, it usually lives around ten to fifteen years, but in captivity can live to an age of 23 years or more.[13] The record for the oldest corn snake in captivity was 32 years and 3 months.[14] The natural corn snake is usually orange or brown bodied with large red blotches outlined in black down their backs.[15] The belly has distinctive rows of alternating black and white marks.[16] This black and white checker pattern is similar to Indian corn which is where the name corn snake may have come from.[17] The corn snake can be distinguished from a copperhead by the corn snake's brighter colors, slender build, slim head, round pupils, and lack of heat-sensing pits.[18]
Until 2002, the corn snake was considered to have two subspecies: the nominate subspecies (P. g. guttatus) described here and the Great Plains rat snake (P. g. emoryi). The latter has since been split off as its own species (P. emoryi), but is still occasionally treated as a subspecies of the corn snake by hobbyists.
P. guttatus has been suggested to be split into three species: the corn snake (P. guttatus), the Great Plains rat snake (P. emoryi, corresponding with the subspecies P. g. emoryi), and Slowinski's corn snake (P. slowinskii, occurring in western Louisiana and adjacent Texas).[19]
P. guttatus was previously placed in the genus Elaphe, but Elaphe was found to be paraphyletic by Utiger et al., leading to placement of this species in the genus Pantherophis.[20] The placement of P. guttatus and several related species in Pantherophis rather than in Elaphe has been confirmed by further phylogenetic studies.[21][22] Many reference materials still use the synonym Elaphe guttata.[23] Molecular data have shown that the corn snake is actually more closely related to kingsnakes (genus Lampropeltis) than it is to the Old World rat snakes (genus Elaphe) with which it was formerly classified. The corn snake has even been bred in captivity with the California kingsnake (Lampropeltis californiae) to produce fertile hybrids known as "jungle corn snakes".[24]
In the wild, the corn snake prefers habitats such as overgrown fields, forest openings, trees, palmetto flatwoods, and abandoned or seldom-used buildings and farms, from sea level to as high as 6,000 ft (1,800 m). Typically, the corn snake remains on the ground until the age of four months but can ascend trees, cliffs, and other elevated surfaces.[25] It can be found in the Southeastern United States ranging from New Jersey to the Florida Keys.
In colder regions, the corn snake brumates during winter. However, in the more temperate climate along the coast, it shelters in rock crevices and logs during cold weather. It also can find shelter in small, closed spaces, such as under a house, and come out on warm days to soak up the heat of the sun. During cold weather, the corn snake is less active; so it hunts less.[26][27]
Often called the "American corn snake", P. guttatus is a proscribed pest in much of Australia. There are active extermination campaigns and advice for the public in Victoria,[28] New South Wales,[29] and Queensland.[30]
It has been found that corn snakes (along with other colubrids) reach sexual maturity by means of size, as opposed to age. [31]
Corn snakes are relatively easy to breed. Although not necessary, they are usually put through a cooling (also known as brumation) period that takes 60–90 days to get them ready for breeding. Corn snakes brumate around 10 to 16 °C (50 to 61 °F) in a place where they cannot be disturbed and with little sunlight.
Corn snakes usually breed shortly after the winter cooling. The male courts the female primarily with tactile and chemical cues, then everts one of his hemipenes, inserts it into the female, and ejaculates his sperm. If the female is ovulating, the eggs will be fertilized and she will begin sequestering nutrients into the eggs, then secreting a shell.
Egg-laying occurs slightly more than a month after mating, with 12–24 eggs deposited into a warm, moist, hidden location. Once laid, the adult snake abandons the eggs and does not return to them. The eggs are oblong with leathery, flexible shells. About 10 weeks after laying, the young snakes use a specialized scale called an egg tooth to slice slits in the egg shell, from which they emerge at about 5 in (13 cm) long.[32]
Reproduction in captivity has to be done correctly so the clutch's mortality rate decreases. This includes accurate sexing, establishing proper pre-breeding conditioning, and timely pairing of adults. Corn snakes are temperate zone colubrids, and share a reproductive pattern where females increase their feeding during summer and fall. This only applies to corn snakes that are sexually mature, which typically indicates the snake is around 75 cm (30 inches) in length or weight 250 g.[33]
Like all snakes, corn snakes are carnivorous and, in the wild, they eat every few days. While most corn snakes eat small rodents, such as the white-footed mouse, they may also eat other reptiles, or amphibians, or climb trees to find unguarded bird eggs.[34]
Seasons play a large role in the thermal regulation patterns of corn snakes, which is the main mechanism of digestion for snakes. During fall, corn snakes maintain a body temperature approximately 3 degrees Celsius higher than the surrounding environment after consuming a meal,[35] while corn snakes in the winter are not seen to thermoregulate after digestion. Captive snakes do this by using heat mats as an underneath heat source replicates their natural conditions. Corn snakes demonstrate nocturnal patterns, and use the warm ground at night to thermoregulate, therefore heat mats replicate this source.
American "rat snakes", such as P. guttatus, had venomous ancestors, which lost their venom after they evolved constriction as a means of prey capture.
Like many species of the Colubridae, corn snakes exhibit defensive tail vibration behavior.[36] Behavioral / chemosensory studies with corn snakes suggest that odor cues are of primary importance for prey detection, whereas visual cues are of secondary importance.[37][38]
However; a study conducted by Dr. David Holzman of the University of Rochester in 1999 found that snakes' cognitive abilities (in specific regards to spatial learning) actually rival that of birds and rodents.[39] Holzman challenged the typical testing method that was being used by biologists to examine snakes' navigational abilities, claiming the structure of the arena itself was biologically in favor of rodents. He hypothesized that if the typical arena being used to test the animals was modified to cater to snake's innate biologically driven goals, thus providing them with problem sets that they would likely encounter in their natural environment, this would give a more accurate view of their intelligence.
The study involved testing 24 captive-bred corn snakes, placing them in a wide-open tub with walls too high for them to climb out. Eight holes were cut out underneath, with one hole leading to a shelter. An intense light was positioned to shine directly on the arena, exploiting the snake's natural aversion to bright open spaces. This provided a biologically meaningful objective for the snakes: to seek out cozy dark shelter.
Not only did they find that, when given proper incentive, the snakes exhibited an acute ability to learn and navigate their surroundings, they also found snakes rely on their sense of vision much more than many herpetologists had previously assumed. They did, however, find that younger snakes were able to more quickly locate the holes than older snakes, as the younger snakes were more resourceful in their application of senses – where the older snakes more heavily relied on their sense of sight.[40]
Corn snakes are one of the most popular types of snakes to keep in captivity or as pets, second only to the ball python. However, they are the most popular pet snake in Brazil. Their size, calm temperament, and ease of care contribute to this popularity. Captive corn snakes tolerate being handled by their owners, even for extended periods.[41]
After many generations of selective breeding, captive bred corn snakes are found in a wide variety of different colors and patterns. These result from recombining the dominant and recessive genes that code for proteins involved in chromatophore development, maintenance, or function. New variations, or morphs, become available every year as breeders gain a better understanding of the genetics involved.
There are tens of thousands of possible compound morphs. Some of the most popular ones are listed here.
Hybrids between corn snakes and any other snake is very common in captivity, but rarely occurs in the wild. Hybrids within the genera Pantherophis, Lampropeltis, or Pituophis so far have been proven to be completely fertile.
Many different corn snake hybrids are bred in captivity. A few common examples include:
When hybrids of corn snakes are found in the wild, they have usually hybridized with other Pantherophis species whose ranges overlap with corn snakes.
A close-up portrait .jpg)
Gravid female 
Young corn snake The corn snake (Pantherophis guttatus), sometimes called red rat snake, is a species of North American rat snake in the family Colubridae. The species subdues its small prey by constriction. It is found throughout the southeastern and central United States. Though superficially resembling the venomous copperhead (Agkistrodon contortrix) and often killed as a result of this mistaken identity, the corn snake lacks functional venom and is harmless. The corn snake is beneficial to humans because it helps to control populations of wild rodent pests that damage crops and spread disease.
The corn snake is named for the species' regular presence near grain stores, where it preys on mice and rats that eat harvested corn (maize). The Oxford English Dictionary cites this usage as far back as 1675, whilst other sources maintain that the corn snake is so-named because the distinctive, nearly-checkered pattern of the snake's belly scales resembles the kernels of variegated corn.
The corn snake is also referred to as a red rat snake.
