king snake
king snake, (genus Lampropeltis), any of a group of moderate-sized to large terrestrial snakes found from southeastern Canada to Ecuador. Adults generally range in length from 1 to 1.5 metres (3.3 to 5 feet), but some have grown to 2.1 metres (6.8 feet). They are nonvenomous constrictors and have a cosmopolitan diet that includes small mammals, birds, snakes, lizards, amphibians, and bird eggs. As a sign of nervousness, king snakes will twitch their tails. King snakes belong to the family Colubridae.
The common king snake (Lampropeltis getula) is found throughout the United States and northern Mexico. It is variable in pattern and may be black or dark brown, with yellow or white stripes, rings, crossbars, or spots. The California king snake (L. getula californiae) exhibits two pattern types, the common ringed pattern and a rarer striped form; both patterns can appear from a single clutch of eggs. King snakes derive their common name from the common king snake’s habit of feeding upon other snakes, including rattlesnakes and copperheads, to whose venom they are immune. Occasionally, king snakes are cannibalistic, even within their own species. In captivity they can survive for 30 years or more. Eggs are laid in clutches of 5–24.
Most other king snakes have a tricoloured pattern of red, black, and yellow rings. The common milk snake (Lampropeltis triangulatum) has one of the largest distributions of any snake, occurring from 48° N to 4° S latitude. Its average length is 1 metre (3.3 feet), with a maximum length of 1.9 metres (6.2 feet). The scarlet king snake (L. elapsoides; considered by some to be the same species as the milk snake) is a small species from the southeastern United States that feeds mainly on lizards. The milk snake and the scarlet king snake are known as false coral snakes because their coloration and pattern mimic those of venomous coral snakes.
Most classifications divide Lampropeltis into six or seven species and several subspecies; however, others identify as many as 20–30 species. Regardless of classification, king snakes are common with stable populations, and thus the International Union for Conservation of Nature and Natural Resources considers all king snakes to be species of least concern.