The corn snake (Pantherophis guttatus ), sometimes called red rat snake [4] is a species of North American rat snake in the family Colubridae. The species subdues its small prey by constriction.[5][6] 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[7] because it helps to control populations of wild rodent pests that damage crops and spread disease.[8] * Coluber guttatus
Linnaeus, 1766
- Elaphis guttatus
— A.M.C. Duméril, Bibron &
A.H.A. Duméril, 1854 - Elaphe guttata
— Stejneger & Barbour, 1917[2] - Pantherophis guttatus
— Utiger et al., 2002[3]
As an adult the corn snake may have a total length (including tail) of 61–182 cm (2.00–5.97 ft).[4] In the wild, it usually lives around ten to fifteen years, but in captivity can live to an age of 23 years or more.[10] The record for the oldest corn snake in captivity was 32 years and 3 months.[11] The natural corn snake is usually orange or brown bodied with large red blotches outlined in black down their backs.[4] The belly has distinctive rows of alternating black and white marks.[4] This black and white checker pattern is similar to Indian corn (maize) which is where the name corn snake may have come from.[4] 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.[12]
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).[13]
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.[14] The placement of P. guttatus and several related species in Pantherophis rather than in Elaphe has been confirmed by further phylogenetic studies.[15][16] Many reference materials still use the synonym Elaphe guttata.[17] 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”.[18]