Lampropeltis alterna (Gray-banded Kingsnake)

Sierra Madre Occidental, Durango

Much of the Sierra Madre Occidental is still “terra incognita” as far as knowledge of the herpetofauna. Certainly this is true for our knowledge of kingsnake distribution. Lampropeltis pyromelana occupies the northern portion of the pine-oak belt in Sonora and Chihuahua, while farther south in Durango, L. greeri makes its appearance. The recently-discovered L. webbi is yet another piece of the puzzle, occurring in warmer and more humid settings west of the range of greeri. A real surprise is that Gray-banded Kingsnakes also range as far west as the mountains of Durango, being found in montane settings more characteristic of pyromelana and greeri. 7600 ft/2315 m elev. (July 2007).