Corn Snake

Corn Snake
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Diapsida
Subclass: Lepidosauria
Order: Squamata
Suborder: Serpentes
Family: Colubridae
Genus: Pantherophis
Species: P. guttatus
Binomial name
Pantherophis guttatus
(Linnaeus, 1766)
Synonyms

Coluber guttatus
Linnaeus,1766

Elaphe guttata
(Linnaeus, 1766)

The Corn Snake (Pantherophis guttatus guttatus), or Red Rat Snake, is a North American species of Rat Snake that subdues its small prey by constriction. The name "Corn Snake" is a holdover from the days when southern farmers stored harvested ears of corn in a wood frame or log building called a crib. Rats and mice came to the corn crib to feed on the corn, and Corn Snakes came to feed on the rodents.[1] The Oxford English Dictionary cites this usage as far back as 1676. Corn Snakes are found throughout the southeastern and central United States. Their docile nature, reluctance to bite, moderate adult size 3.9–5.9 feet (1.2–1.8 m), attractive pattern, and comparatively simple care make them popular pet snakes. In the wild, they usually live around 6–8 years, but in captivity can live to be up to 23 years old.[2]

Contents

Taxonomy

There are two subspecies of Pantherophis guttatus:

It has been suggested that Pantherophis guttatus be split into three species: Pantherophis guttatus, Pantherophis emoryi (corresponding with the subspecies Pantherophis guttatus emoryi) and Pantherophis slowinskii (occurring in western Louisiana and adjacent Texas).[3]

Pantherophis 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.[4] The placement of Pantherophis guttatus and several related species in Pantherophis rather than Elaphe has been confirmed by further phylogenetic studies.[5][6]

Natural habitat

Wild Corn Snakes prefer 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 feet. Typically, these snakes remain on the ground, but can ascend trees, cliffs and other elevated surfaces.[7] They can be found in the southeastern United States ranging from New Jersey to the Florida keys and as far west as Texas.

In colder regions, snakes hibernate during winter. However, in the more temperate climate along the coast they shelter in rock crevices and logs during cold weather, and come out on warm days to soak up the heat of the sun, a process known as brumation. During cold weather, snakes are less active and therefore hunt less.

Reproduction

Corn snakes are relatively easy to breed. First they have to go through a cooling (also known as brumation) period that takes usually 60-90 days long. This is to get them ready for breeding and to tell them that its time to reproduce. Corns brumate at around 10 to 16 °C (50 to 61 °F) in a place where they can not get disturbed and not worry about predators. When its summer they go out to warm up to their regular temperature.

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 a leathery, flexible shell. Approximately 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 inches in length.

Variations

After many generations of selective breeding, domesticated 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.

Color morphs

Pattern morphs

Compound morphs

There are tens of thousands of possible compound morphs. Some of the most popular are listed.

Intergrades

Hybrids

References

  1. ^ http://www.flmnh.ufl.edu/herpetology/fl-guide/pantherophisguttatus.htm
  2. ^ Corn Snake Fact sheet
  3. ^ Burbrink, F. T., 2002. Phylogeographic analysis of the corn snake (Elaphe guttata) complex as inferred from maximum likelihood and Bayesian analyses. Molecular Phylogenetics and Evolution 25: 465-476.
  4. ^ Utiger, U., N. Helfenberger, B. Schätti, C. Schmidt, M. Ruf, and V. Ziswiler, 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.
  5. ^ Burbrink, F. T. and R. Lawson, 2007. How and when did Old World ratsnakes disperse into the New World? Molecular Phylogenetics and Evolution 43: 173-189.
  6. ^ Pyron, R. A. and F. T. Burbrink, 2009. Neogene diversification and taxonomic stability in the snake tribe Lampropeltini (Serpentes: Colubridae) Molecular Phylogenetics and Evolution 52: 524-529.
  7. ^ Peterson Field Guide - Western Reptiles and Amphibians - 3rd Edition
  8. ^ CCCorns - Corn Snake Star Gazer Information Page

External links